Abstract: BACKGROUND: Surgical mortality for acute type A aortic dissection is frequently related to preoperative clinical conditions. We report a predictive score to identify risk of death that may be helpful to assist surgeons who are considering whether to proceed with surgical correction in the case of patients in extreme clinical risk. METHODS: Surgical outcome of 682 patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2003 was analyzed. Two different models were used. The initial model included only preoperative variables such as demographics, history, symptoms, signs, and diagnostic methods (model 1). The second model also tested intraoperative hemodynamic and surgical variables (model 2). A bedside risk prediction tool to predict operative mortality in individual patients was developed. RESULTS: The overall in-hospital surgical mortality was 23.9%. Independent preoperative predictors of mortality in model 1 were age greater than 70 years, prior cardiac surgery, hypotension (systolic blood pressure less than 100 mm Hg) or shock at presentation, migrating pain, cardiac tamponade, any pulse deficit, and electrocardiogram with findings of myocardial ischemia or infarction. In model 2, other predictors of surgical death were intraoperative hypotension, a right ventricle dysfunction at surgery, and a necessity to perform coronary revascularization. An independent predictor for favorable surgical outcome was right hemiarch replacement. CONCLUSIONS: Surgery in unstable patients with acute type A aortic dissection can be highly unsuccessful. The International Registry of Acute Aortic Dissection risk models predict in-hospital mortality using a multivariable risk prediction tool, useful for surgeons and patients as they consider their surgical risk and the pros and cons of embarking on high-risk surgery.

Abstract: BACKGROUND: Paclitaxel-eluting stents (PES) have been proved effective in randomized trials enrolling highly selected patients. Yet, given the uncertainty concerning results of PES implantation in very high-risk patients and lesions, we designed a prospective multicenter registry, the Taxus in Real-life Usage Evaluation (TRUE) Study. STUDY DESIGN, PATIENT CHARACTERISTICS AND IN-HOSPITAL OUTCOMES: Consecutive patients undergoing PES implantation were enrolled provided that the target lesion treated with PES was an unprotected left main (ULM), a true bifurcation, a chronic total occlusion (CTO), a long lesion (>28 mm), located in a small vessel (<2.75 mm), or the patient had diabetes mellitus. Clinical events will be adjudicated at 1, 7 and 12 months, with 4- to 8-month angiographic follow-up. The primary end-point will be the 7-month occurrence of major adverse cardiovascular events (MACE, i.e. the composite of cardiac death, non-fatal myocardial infarction [MI], coronary artery bypass grafting [CABG] and percutaneous target vessel revascularization [TVR]). To date, patient enrollment has been completed reaching the target of 1065 subjects. These included 322 (30.2%) diabetics, 115 (10.8%) subjects undergoing PES implantation for ULM, 229 (21.5%) in a bifurcation, 191 (17.9%) in a CTO, 430 (40.4%) in a small vessel, and 289 (27.1%) in a long lesion. An average of 1.5+/-0.6 vessels and 2.0+/-1.0 lesions were treated per patient, with 2.0+/-1.2 PES implanted per patient, and a 46+/-30 mm total PES length per patient. In-hospital MACE occurred in 39 (3.7%) patients, with 2 (0.2%) cardiac deaths, 32 (3.0%) MI, 5 (0.5%) TVR, no CABG, and 4 (0.4%) acute stent thromboses. IMPLICATIONS: Despite the availability of randomized trials, only carefully designed and prospective registries can provide timely and accurate assessment of the risk-benefit profile of PES in very high-risk patients. Indeed, the TRUE Study, including as much as 115 ULM and 229 bifurcation interventions, should give important insights into the outcome of PES in such an unprecedented and challenging context.

Abstract: OBJECTIVES: The aim of the study was the assessment of the clinical, angiographic and procedural characteristics correlated with freedom from adverse events at 1 year in a real life setting of consecutive bifurcation lesions. BACKGROUND: Even if stent implantation has shown to be superior to conventional balloon angioplasty in most coronary lesions, bifurcation treatment with stent implantation both in main and in side branch (SB) still raises controversy. METHODS: We reviewed the results obtained in a prospective multicenter registry of 150 patients with 158 bifurcation lesions involving a SB of sufficient diameter to be treated, if necessary, with a polymer based paclitaxel eluting stent (PES, TAXUS). Two stents were used in 118 lesions (74.7%). Final kissing balloon inflation was performed in 87/118 lesions (73.7%) and in 30/40 lesions (75.0%) of the 2 and 1 stent group respectively. RESULTS: At 1-year clinical follow-up we observed 4 stent thromboses, all involving the SBs of the 2 stents group (2.7%). Unlike previous reports, revascularization involved the main vessel in the majority of patients (21/150, 14.0%). After an exploratory multivariable analysis the only parameter predictive of target lesion revascularization (TLR) (HR 0.52; CI 95% 0.11-0.86; p = 0.02) and target vessel revascularization (TVR) (HR 0.47; CI 95% 0.14-0.90; p = 0.03) was postprocedural main branch minimal lumen diameter (MB-MLD). CONCLUSIONS: In a real life setting of consecutive bifurcation lesions, thrombosis rate, concentrated in the SB and the 2-stents group, and need for target lesion revascularization remain higher than in less complex lesion subgroups treated with PES. No differences in immediate success and TLR were observed between 2 stents and 1 stent groups. The frequently observed suboptimal stent expansion and final MB-MLD predict 1 year revascularization.

Abstract: BACKGROUND: Currently, little data are available on the management of drug-eluting stent (DES) restenosis. Drug resistance may play a role in its etiology. METHODS: We identified all cases of either sirolimus-eluting or paclitaxel-eluting stent restenosis treated with repeated DES implantation. The lesions were divided into those receiving the same DES as the one that restenosed and those treated with the alternative DES. The end points analyzed were target lesion revascularization (TLR) and angiographic restenosis. RESULTS: We included 201 lesions (174 patients); the same DES was implanted in 107 lesions and a different DES in 94 lesions. Angiographic follow-up of the retreatment was available in 69.7% of the lesions. Angiographic restenosis occurred in 26.4% (19) of cases treated with the same DES and 25.8% (17) of those treated with a different DES (P = 1.0). Target lesion revascularization occurred in 15.9% (17) and 16% (15) of lesions, respectively (P = 1.0). A multivariate analysis confirmed the lack of association between the treatment selected and TLR (OR 0.7, 95% CIs [0.29-1.67]; P = .42). A nonfocal pattern of restenosis remained associated with TLR and restenosis (OR 2.99, 95% CIs [1.24-7.24]; P = .015 and OR 3.6, 95% CIs [1.5-8.8]; P = .004, respectively). CONCLUSIONS: Repeated DES implantation for DES restenosis is feasible and safe. The TLR rate is acceptable, with no differences between implantation of the same or a different DES. The pattern of restenosis treated is an important predictor of outcomes.

Abstract:

Abstract: Late loss is becoming an important end point to compare drug-eluting stents; however, little is known about its pattern of distribution. We analyzed the pattern of late loss distribution in sirolimus-eluting stents (SESs) and paclitaxel-eluting stents (PESs) in a consecutive cohort of patients. From a cohort of 529 patients treated with drug-eluting stents in 1 year, we selected all patients who underwent angiographic follow-up. Three hundred fifty-nine patients with 592 de novo lesions received SESs (286 lesions) or PESs (306 lesions). Late loss and binary angiographic restenosis were analyzed. Binary restenosis occurred in 56 lesions (19.6%) treated with SESs compared with 53 (17.3%) treated with PESs (p = 0.48). The 2 late loss distributions were skewed to the right and were not normally distributed (p <0.001 for SES, p = 0.003 for PES). Late loss was significantly lower in the SES group (p = 0.03), with a median value of 0.29 mm (interquartile range -0.09 to 0.66) versus 0.41 mm (-0.02 to 0.85) in the PES group. When analyzing only restenotic lesions, late loss had a normal distribution in the SES and PES groups (p = 0.96 and 0.44, respectively) and was similar in the 2 groups (1.75 +/- 0.51 vs 1.82 +/- 0.62, p = 0.48). When evaluating nonrestenotic lesions, late loss was also normally distributed in the 2 groups (p = 0.75 for SES, p = 0.73 for PES) but was significantly lower (p = 0.002) after SES implantation (0.14 +/- 0.39) than after PES implantation (0.27 +/- 0.44). In conclusion, SESs and PESs have a bimodal pattern of late loss distribution. The observed difference in late loss between SES and PES seems to be partly explained by the decrease in late loss after SES implantation in nonrestenotic lesions (where SES approaches "zero late loss"). Thus, late loss may not be a reliable marker of the true efficacy of these devices due to its complex and nongaussian distribution.

Abstract: Inflammation plays a major role in all phases of atherosclerosis. Stable plaques are characterized by a chronic inflammatory infiltrate, whereas vulnerable and ruptured plaques are characterized by an "active" inflammation involved in the thinning of the fibrous cap, predisposing the plaque to rupture. Although a single vulnerable atherosclerotic plaque rupture may cause the event, there are many other types of plaques, several of which are vulnerable. The existence of multiple types of vulnerable plaques suggests that atherosclerosis is a diffuse inflammatory process. A current challenge is to identify morphologic and molecular markers able to discriminate stable plaques from vulnerable ones, allowing the stratification of patients at high risk for acute cardiovascular and cerebrovascular events before clinical syndromes develop. With that aim in mind, this article summarizes the natural history of atherosclerotic plaques, focusing on molecular mechanisms affecting plaque progression and serum markers correlated with plaque inflammation.

Abstract: Combined antiplatelet treatment with aspirin and clopidogrel is pivotal to minimize periprocedural adverse events in patients who undergo percutaneous coronary intervention. However, there is debate on the best clopidogrel loading dose. The investigators performed a systematic review and meta-analysis of the optimal clopidogrel loading dose. Pertinent trials comparing high (>300 mg) and standard (300 mg) clopidogrel loading doses in patients scheduled for catheterization and/or percutaneous coronary intervention were systematically searched in BioMedCentral, CENTRAL, Google Scholar, and PubMed (December 2006). The primary end point was the 1-month rate of death or myocardial infarction. Secondary end points included other ischemic and bleeding adverse effects. Peto odds ratios were computed. A total of 10 studies (7 randomized, 3 nonrandomized) were included, enrolling 1,567 patients (712 loaded with 300 mg, 11 with 450 mg, 790 with 600 mg, and 54 with 900 mg). Overall, a high loading dose proved significantly superior to a standard loading dose in preventing cardiac death or nonfatal myocardial infarction (odds ratio 0.54, 95% confidence interval 0.32 to 0.90, p = 0.02), without any statistically significant increase in major or minor bleedings (p = 0.55 and p = 0.98, respectively). Sensitivity analysis restricted to randomized trials confirmed the superiority of a high loading dose regimen (p = 0.0031). Meta-regression disclosed a significant interaction between event rate and the benefits of high loading doses (p = 0.005), suggesting that the greater the underlying risk, the greater the favorable impact of a high loading dose. In conclusion, a high clopidogrel loading dose (>300 mg) significantly reduces early ischemic events in patients scheduled for percutaneous coronary intervention.

Abstract:

Abstract: BACKGROUND: Clopidogrel is an established alternative to ticlopidine in addition to aspirin after coronary stenting because of its safety, but its optimal initial dosing is unclear. We performed a systematic review and meta-regression of randomized clinical trials comparing clopidogrel versus ticlopidine, focusing on clopidogrel front-loading. METHODS: PubMed was searched for pertinent studies (updated August 2006). Random-effect odds ratios (ORs) with 95% CIs were computed for death or nonfatal myocardial infarction, and weighted least squares random-effect meta-regression was performed to explore the impact of loading versus nonloading clopidogrel scheme. RESULTS: We retrieved 7 trials (3382 patients, average follow-up of 7 months). In 5 studies, both clopidogrel and ticlopidine were started with a loading dose, in 1 trial clopidogrel was administered without loading, and in 1 trial clopidogrel could be administered with or without loading. Overall analysis (P for heterogeneity = .02) showed similar results for clopidogrel and ticlopidine (OR 0.90, 95% CI 0.44-1.84, P = .77). In studies administering clopidogrel with loading, this treatment was, however, significantly better than ticlopidine (OR 0.60, 95% CI 0.36-0.99, P = .05). This significant interaction between clopidogrel loading and its superiority in comparison with ticlopidine was also formally confirmed by meta-regression (beta = -0.64, P = .012). CONCLUSIONS: This work supports the superiority of a clopidogrel regimen including an initial loading dose in comparison with ticlopidine in patients undergoing coronary stenting.

Abstract: The implantation of coronary stents is a relevant part of interventional procedures for percutaneous revascularization. The wide acceptance of coronary stenting was based on the results of two highly significant trials which have shown the superiority of stenting over balloon angioplasty in terms of reduction of angiographic restenosis and need for repeated intervention in focal lesions and large coronary arteries. Since then, the growing use of stent market was impressive. A rapidly increasing number of different stent type with different material and designs has been introduced in the market both for bare metal stent and drug eluting stent. This review will summarize the different components of stent design that are important in term of biological response of the arterial wall and clinical outcome. In addition, new stent platforms, mainly represented by the biodegradable stent will be shortly reviewed since it may provide in the near future a more "physiological" answer to stent implantation, reducing vascular injury and accelerating vessel healing with consequent improving in clinical outcome.

Abstract: BACKGROUND: The presence of a lumen narrowing at the ostium and the body of an unprotected left main coronary artery but does not require bifurcation treatment is a class I indication of surgical revascularization. METHODS AND RESULTS: A total of 147 consecutive patients who had a stenosis in the ostium and/or the midshaft of an unprotected left main coronary artery (treatment of the bifurcation not required) and were electively treated with percutaneous coronary intervention and sirolimus-eluting stents (n=107) or paclitaxel-eluting stents (n=40) in 5 centres were included in this registry. In 72 patients (almost 50%), intravascular ultrasound guidance was performed. Procedural success was achieved in 99% of the patients; in 1 patient with stenosis in the left main coronary artery ostium, a >30% residual stenosis persisted at the end of the procedure, and the patient was referred for coronary artery bypass graft surgery. During hospitalization, no patients experienced a Q-wave myocardial infarction or died. One patient died 19 days after the procedure because of pulmonary infection. At long-term clinical follow-up (886+/-308 days), 5 patients had died; 7 patients had target vessel revascularization (5 repeat percutaneous coronary interventions and 2 coronary artery bypass graft surgeries), and of these only 1 patient had a target lesion revascularization. Angiographic follow-up was performed in 106 patients (72%) with a late loss of -0.01 mm. Restenosis in the left main trunk occurred only in 1 patient (0.9%). CONCLUSIONS: Percutaneous coronary intervention with sirolimus-eluting stents or paclitaxel-eluting stents implantation in nonbifurcation left main coronary artery lesions appears safe with a long-term major adverse clinical event rate of 7.4% and a restenosis rate of 0.9%.

Abstract: The Italian Society of Interventional Cardiology is aware of the existence of significant local and individual disparities and discordant prescriptions in antiplatelet therapy administered with coronary stents, a critical issue due to the large use of drug-eluting stents (DES), the increasing complexity of percutaneous coronary interventions and the more stringent requirement to avoid stent thrombosis. Current percutaneous coronary intervention is attempting more aggressively to treat difficult lesions and patient cohorts with a high procedural success rate. Double antiplatelet therapy with aspirin (ASA) and thienopyridine is the best current treatment to reduce the risk of coronary stent thrombosis. Due to the lower incidence of side-effects compared to ticlopidine, clopidogrel should be the thienopyridine of choice in association with ASA in the double antiplatelet regimen. However, the combination of delayed healing with DES and the increasing complexity of the stent implantation raises more demanding safety concerns about the dosage and duration of dual antiplatelet therapy.

Abstract: Atherosclerotic plaque at the carotid bifurcation is the primary cause of ischemic strokes and the degree of carotid stenosis is strongly associated with stroke risk in symptomatic patients. Stroke is the third-leading cause of death in the United States, constituting approximately 700,000 cases each year. In this article, the authors discuss the natural history of carotid and intracranial atherosclerosis, based on their broader knowledge of coronary atherosclerosis. Early to more advanced progressive lesions of the carotid are categorized, based on descriptive morphologic events originally cited for the coronary circulation. The histologic features associated with symptomatic and asymptomatic carotid disease are also addressed, along with the issues surrounding current stent-based therapies for the prevention of major recurrent vascular events.

Abstract: BACKGROUND: There is no specific study evaluating the outcome of DES implantation in trifurcation lesions. OBJECTIVE: To evaluate the mid-term clinical and angiographic outcome of drug-eluting stent (DES) implantation in trifurcation lesions. METHODS: All complications and major adverse cardiac events, including cardiac death, Q-wave myocardial infarction (MI), target lesion revascularization (TLR), and target vessel revascularization (TVR) were recorded in-hospital and during clinical follow up. RESULTS: A total of 15 consecutive patients undergoing percutaneous coronary intervention with DES in de novo trifurcation lesions were identified. Lesions were located as follows: 13 (86.7%) at the distal left main coronary artery (LMCA) comprising the left anterior descending artery (LAD), the left circumflex artery (LCX) and an intermediate branch; 1 between the LAD, diagonal, and septal branches; and 1 between the LCX, obtuse marginal and posterior lateral branches. Stenting was performed in all 3 branches in 8 patients, in 2 branches in 6 patients, and in 1 branch in 1 patient. The mean follow-up period was 19.0 +/- 8.3 months. TLR occurred in 3 patients (20%) with LMCA lesions. TVR occurred in 6 patients (40%). Of those, 3 were due to TLR, while the other 3 for progression of nontarget lesions. No deaths, Q-wave MIs or stent thromboses were recorded. CONCLUSION: Most trifurcation lesions were found in the distal LMCA. DES implantation in trifurcation lesions can be performed with a low incidence of death, Q-wave MI or stent thrombosis.

Abstract: Stroke is the second cause of mortality in industrialized countries. Atherosclerotic plaque rupture with atheromatous debris distal embolization is the pathogenetic mechanism responsible for cerebrovascular events due to atherosclerotic carotid disease. Plaque composition rather than lesion burden seems to be the determinant factor producing rupture and subsequent thrombosis. Histologic features of vulnerability are : a large lipid core, a thin fibrous cap, and an inflammatory infiltrate rich of monocytes and macrophages. In the clinical practice, it is difficult to predict the risk of experiencing a major cerebrovascular events especially in asymptomatic patients. New invasive techniques such as intravascular ultrasound with termography, optical coherence tomography, fotons spectroscopy and elastography have been developed to detect atherosclerotic lesion tissue composition. However, such techniques are difficult to apply on a large scale basis in primary prevention. On the contrary, new serologic biomarkers such as Pregnancy Associated Plasma Protein-A, Lp-PLA2, Interleukin-6, Interleukin-12, metalloproteinases, lipoprotein-(a), and plaque oxidative products have been recently proposed for screening general and high risk population. The present paper will briefly review the current histologic characteristics of vulnerable plaque and the new imaging tools proposed for its detection, focusing on the most recent serologic biomarkers evaluated in the clinical practice to increase our accuracy in predicting not only the plaque but moreover the patient at risk for an acute cerebrovascular event.

Abstract:

Abstract: A 25-year-old semiprofessional soccer player was referred to our hospital because of intermittent claudication of the right leg. He had right limb trauma while playing soccer, and a selfexpandable stent was implanted for the occluded femoropopliteal artery. One month later, he complained of acute recurrence of claudication. Angiography revealed an occlusion of the stent due to cross-sectional stent squeeze and partial fracture. The occlusion was successfully revascularized with additional stenting. The patient was asymptomatic at 5-month follow up. Early self-expandable stent squeeze is quite rare. The forces exerted in the popliteal artery while playing soccer may have caused this phenomenon.

Abstract: Renal artery aneurysms are rare vascular anomalies in which rupture is associated with devastating consequences. Only a few reported cases involved percutaneous treatment. Recently, technological advances have expanded indications for percutaneous treatment of such complex peripheral lesions. Despite this, certain anatomical settings such as extreme vessel tortuosity or angulation of the afferent vessel continue to pose challenges. New steerable devices may play a crucial role in those cases where conventional techniques have failed. We report a case of successful percutaneous treatment of a renal artery aneurysm and stenosis in a young male using the Venture catheter.

Abstract: BACKGROUND: The safety and efficacy of drug-eluting stents (DES) implantation in unprotected left main (LM) bifurcation lesions has yet to be determined. The aim of the present report was to evaluate the long-term outcome following implantation of DES in unprotected LM bifurcation lesions. METHODS: We identified 70 consecutive patients treated with DES in unprotected LM bifurcation lesions from April 2003 to January 2005. Of them, 42 patients were treated with sirolimus-eluting stent (SES) and 28 patients were treated with paclitaxel-eluting stent (PES). RESULTS: Stents to the left anterior descending and to the circumflex were implanted in 62 patients. During 1-year follow-up, 3 (4.3%) patients died of cardiac causes. One of them had myocardial infarction and adjudicated as possibly due to stent thrombosis. Angiographic follow-up was available in 80% of patients. The per lesion restenosis rate was 13.4% in the entire cohort, of which 10.7% occurred in lesions treated with SES and 16.1% in those treated with PES (P = 0.58). All restenosis was focal and occurred in the lesions treated with a stent with stent size to post-procedural reference vessel diameter ratio < 1.0 (17.6% vs 0, P = 0.04). The per patient target lesion revascularization rate at 1 year was 17.1%. One year survival free from major adverse cardiac events was 77.1%. CONCLUSIONS: Treatment of LM bifurcation lesions using DES is a safe and feasible way with a low one-year mortality. The need for revascularization in 17% of patients demands for improvement.

Abstract: Drug-eluting stents (DES) present a slightly higher incidence of stent thrombosis compared to bare metal stents and some cases of DES thrombosis are described in the literature. Therefore, there is consensus in recommending treatment with clopidogrel for at least 6 months in addition to life-long aspirin administration. We describe a case of very late paclitaxel-eluting stent thrombosis despite 21 months of clopidogrel treatment, which occurred just 2 weeks after its withdrawal, causing an acute coronary syndrome that was promptly resolved with an urgent invasive strategy. In our experience, paclitaxel-eluting stent thrombosis can occur several months after stent implantation despite prolonged clopidogrel treatment.

Abstract: Identification of so-called "vulnerable plaque" or "high-risk" plaques have spawned manifold attempts to develop diagnostic tools capable to afford this task. This task is particularly challenging but the reward is high: local intervention on identified "vulnerable plaque" could preclude plaque thrombosis and possibly prevent acute coronary syndromes. Various imaging techniques are currently under investigation by extensive clinical testing to identify which could become the most sensible and specific modality for vulnerable plaque detection. Noninvasive techniques are fascinating for their easily applicability to a broad population but nowadays are not sufficiently powered for this task. The emerging technologies with the greatest resolution are indeed catheter-based and many intravascular modalities have been developed for identification of "vulnerable plaque". Among these, IVUS-Virtual Histology (IVUS-VH) is the most promising technique in the field. IVUS-VH offers an in vivo opportunity to assess plaque morphology and histology. IVUS-VH uses underlying frequency information along with echoes intensity, while grey-scale IVUS data are obtained from echoes of different intensity or amplitude. The major advantage of IVUS-VH is that it is based on a device that is practical for use in the clinical setting and that it generates a real-time assessment of plaque morphology. Unfortunately, numerous challenging issues still need to be overcome until the numerous "vulnerable plaques" could be identified and successfully treated. Future efforts may identify plaques that are on a trajectory of evolution toward a vulnerable state, and help us target interventions to those plaques most likely to develop plaque disruption and related complications.

Abstract: BACKGROUND: The need for prolonged aspirin and thienopyridine therapy and the risk of stent thrombosis (ST) remain as drawbacks associated with drug-eluting stents. METHODS AND RESULTS: A prospective observational cohort study was conducted between June 2002 and January 2004 on 3021 patients consecutively and successfully treated in 5389 lesions with drug-eluting stents. Detailed patient information was collected on antiplatelet therapy. We analyzed the incidence of ST throughout the 18-month follow-up period and its relationship with thienopyridine therapy. ST occurred in 58 patients (1.9%) at 18 months. Forty-two patients (1.4%) experienced the event within 6 months of stent implantation. Acute myocardial infarction (fatal or nonfatal) occurred in 46 patients (79%) and death in 23 patients (39%) with ST. The median interval from discontinuation of thienopyridine therapy to ST was 13.5 days (interquartile range 5.2 to 25.7 days) for the first 6 months and 90 days (interquartile range 30 to 365 days) between 6 and 18 months. On multivariable analysis, the strongest predictor for ST within 6 months of stenting was discontinuation of thienopyridine therapy (hazard ratio, 13.74; 95% CI, 4.04 to 46.68; P<0.001). Thienopyridine discontinuation after 6 months did not predict the occurrence of ST (hazard ratio, 0.94; 95% CI, 0.30 to 2.98; P=0.92). CONCLUSIONS: Discontinuation of thienopyridine therapy was the major determinant of ST within the first 6 months, but insufficient information is available to determine whether there is benefit in continuing a thienopyridine beyond 6 months.

Abstract: Despite encouraging results from randomized trials, concerns exist about long-term results of sirolimus-eluting stent implantation. We sought to determine whether in-stent restenosis occurring >1 year ("late") after sirolimus-eluting stent implantation is a real clinical entity. We analyzed data on all sirolimus-eluting stents implanted in our institution before March 2003. During the study period 928 lesions in 433 patients were treated. Angiographic follow-up was performed in 306 patients (70.6%) with 679 lesions (73.2%). Angiography after 1 year was performed only in symptomatic patients. We considered restenosis "early" if it occurred during the first year and late if after 1 year. Late restenosis required demonstration of a widely patent stent at 6 to 9 months, with repeat angiography after 1 year demonstrating restenosis. Restenosis occurred in 160 lesions overall (23.5%). Of the 31 (4.6%) that were documented after 1 year, 13 were excluded from analysis due to absence of 6- to 9-month angiography; the remaining 18 (2.6%, 1.7 to 4.2) fulfilled our criteria for late restenosis (median time of documentation 607 days, interquartile range 511 to 923). In conclusion, late restenosis is an infrequent but real entity; its existence implies we should not discount the possibility of restenosis as the cause of symptoms that develop >1 year after sirolimus-eluting stent implantation.

Abstract: OBJECTIVES: This study was designed to compare the outcomes of paclitaxel-eluting stents (PES) and sirolimus-eluting stents (SES) in a contemporaneous cohort of real-world patients. BACKGROUND: A number of randomized comparisons of PES and SES have shown unequivocal advantages for SES in angiographic end points such as late loss. However, the data on clinical outcomes are less consistent. METHODS: All consecutive patients successfully treated with only SES or PES in de novo native vessel lesions between March 2003 and March 2005 were analyzed. Our end points were major adverse cardiac events (MACE), a composite of death, myocardial infarction (MI), target vessel revascularization (TVR), and target lesion revascularization (TLR). We also analyzed late loss and angiographic restenosis. RESULTS: There were 609 patients (1,064 lesions) treated with PES and 674 patients (1,205 lesions) treated with SES. Diabetes mellitus was present in 26.8% of patients and multivessel disease in 75% of patients. Bifurcations made up 16.3% of lesions, chronic occlusions 9.5%, left main 4.8%, and American Heart Association/American College of Cardiology type B2/C 75.4%. Despite a higher late loss in the PES group (p = 0.0001), there were no differences in angiographic restenosis (PES 18% vs. SES 17.8%, p = 0.95), TLR (PES 11.9% vs. SES 11%, p = 0.47), or MACE (PES 21.3% vs. SES 21.1%, p = 0.95). The relative risk of MACE for the PES group was 1.02 (95% confidence interval [CI] 0.78 to 1.33). Multivariable analysis confirmed the lack of association of stent type with MACE (odds ratio 1.03 [95% CI 0.77 to 1.38], p = 0.83) and TLR (odds ratio 1.08 [95% CI 0.81 to 1.44], p = 0.61). CONCLUSIONS: In this complex cohort, both stent platforms demonstrated similar clinical outcomes despite different late loss.

Abstract: AIMS: The role of aspirin in patients with coronary artery disease (CAD) is well established, yet patients happen to discontinue aspirin according to physician's advice or unsupervised. We thus undertook a systematic review to appraise the hazards inherent to aspirin withdrawal or non-compliance in subjects at risk for or with CAD. METHODS AND RESULTS: Electronic databases were systematically searched (updated January 2006). Study designs, patient characteristics, and outcomes were abstracted. Pooled estimates for odds ratios (OR) were computed according to random-effect methods. From the 612 screened studies, six were selected (50,279 patients). One study (31,750 patients) focused on adherence to aspirin therapy in the secondary prevention of CAD, two studies (2594) on aspirin discontinuation in acute CAD, two studies (13,706) on adherence to aspirin therapy before or shortly after coronary artery bypass grafting, and another (2229) on aspirin discontinuation among patients undergoing drug-eluting stenting. Overall, aspirin non-adherence/withdrawal was associated with three-fold higher risk of major adverse cardiac events (OR=3.14 [1.75-5.61], P=0.0001). This risk was magnified in patients with intracoronary stents, as discontinuation of antiplatelet treatment was associated with an even higher risk of adverse events (OR=89.78 [29.90-269.60]). CONCLUSION: Non-compliance or withdrawal of aspirin treatment has ominous prognostic implication in subjects with or at moderate-to-high risk for CAD. Aspirin discontinuation in such patients should be advocated only when bleeding risk clearly overwhelms that of atherothrombotic events.

Abstract: BACKGROUND: Antegrade femoral access is fraught by technical challenges and steeper learning curve, in comparison with retrograde contralateral femoral access. We appraised learning curve, complications, and technical aspects inherent in the adoption of antegrade approach. METHODS: Consecutive cases in which antegrade access was attempted by a cardiologist experienced in retrograde access, but inexperienced in antegrade, under supervision of an operator with anterograde expertise, were collected. The primary end-point was the occurrence of antegrade access failure or local complications. Major complications were defined as those life-threatening, requiring transfusion, percutaneous, or surgical repair. RESULTS: Anterograde access was attempted in 120 patients. The primary end-point occurred in 14 (11.6%) cases, but according to the learning curve, in 12 (20%) for first 60 cases vs 2 (3.3%) for the last 60 cases (P = 0.008). Access failure in the hands of the in-training operator was similarly found in all cases but one during the first 60 cases. No major complications occurred, while minor complications were found in 9 (7.5%) patients, again with all but two of them occurring in the first 60 cases. These included peri-adventitial extravasation in 8 patients (6.7%), and perforation of a small branch in one (0.8%); all these complications were conservatively and successfully managed. Obesity was the only significant predictor of access failure/complication (P = 0.004). CONCLUSIONS: This work, the first to report on the learning curve of the antegrade approach, supports the feasibility and safety of this access site even for an in-training operator, if supervised. A minimum caseload of 60 procedures is likely needed to master this technique.

Abstract: Randomized trials have shown that implantation of sirolimus-eluting stents (SESs) and paclitaxel-eluting stents (PESs) reduce the incidence of major adverse cardiac events (MACEs) compared with bare metal stents. We compared the impact of SESs and PESs on clinical outcome in medically treated diabetic patients with multivessel stents. In this study, the in-hospital and 9-month clinical outcomes of 260 consecutive diabetic patients who underwent implantation of SESs (147 patients) or PESs (113 patients) were compared. MACEs were defined as death, nonfatal myocardial infarction, and clinically driven target vessel revascularization. The baseline demographic and angiographic characteristics were well matched. An average of 3.0 +/- 1.3 versus 2.8 +/- 1.2 lesions were treated in the SES and PES groups, respectively (p = 0.34), with a mean stented length per patient of 73 +/- 43 versus 61 +/- 36 mm (p = 0.08). No significant difference was observed between the SES and PES groups for in-hospital (6.1% vs 3.5%, p = 0.34) or 9-month MACE (24.5% vs 19.5%, p = 0.34) rates or for subacute (1.4% vs 0.9%, p = 0.72) or late (0.7% vs 0.9%, p = 0.85) stent thrombosis. Insulin-requiring diabetic patients treated with SESs and PESs also had similar demographic and angiographic characteristics and rates of in-hospital (4.7% vs 7.7%, p = 0.57) and 9-month (28.0% vs 38.4%, p = 0.44) MACEs. Insulin-dependent diabetes was the only independent predictor of MACEs (odds ratio 2.68, 95% confidence interval 1.46 to 4.89, p = 0.001). In conclusion, our results demonstrated a relatively high incidence of MACEs in a diabetic population with multivessel disease, despite treatment with drug-eluting stents. In addition, we could not find any clear advantage of 1 type of stent versus the other.

Abstract: OBJECTIVES: The study aim was to evaluate serologic expression of pregnancy-associated protein-A (PAPP-A) in patients affected by cerebrovascular accidents and to correlate it with histopathologic carotid plaque complexity. BACKGROUND: Little is known about PAPP-A expression in carotid atherosclerotic disease and whether this protein represents a marker of plaque vulnerability also in carotid district. METHODS: Seventy-two carotid plaques from patients submitted to surgical endarterectomy (19 who suffered a major stroke, 24 transient ischemic attack, and 29 asymptomatic) were evaluated. Serologic PAPP-A levels were determined by enzyme-linked immunoadsorbent assay. Plaques were divided in three groups based on histology: 1) stable (n = 38); 2) vulnerable (n = 13); 3) ruptured with thrombus (n = 14). Immunohistochemical staining for PAPP-A, smooth muscle cells, macrophages, and T-lymphocytes was performed in all cases. Real-time polymerase chain reaction assessed local PAPP-A production, and double immunofluorescence confocal microscopy (ICM) characterized cell type expressing PAPP-A. RESULTS: Pregnancy-associated protein-A (serologic values were 4.02 +/- 0.18 mIU/l in Group 1, 7.43 +/- 0.97 mIU/l in Group 2, and 6.97 +/- 0.75 mIU/l in Group 3 [1 vs. 3, p = 0.01; 1 vs. 2, p = 0.004; 2 vs. 3, p = 0.71, respectively]). Pregnancy-associated protein-A (expression showed a mean score value of 0.62 +/- 0.06 for stable plaques, 2.54 +/- 0.14 for vulnerable plaques, and 2.71 +/- 0.12 for ruptured plaques [1 vs. 2, p = 0.001; 1 vs. 3, p = 0.001; 2 vs. 3, p = 0.37, respectively]). Real-time polymerase chain reaction demonstrated local messenger ribonucleic acid PAPP-A production, and double ICM confirmed monocyte/macrophage expression of PAPP-A in Groups 2 and 3 but not Group 1. CONCLUSIONS: This study suggests that PAPP-A is a marker of carotid plaque destabilization and rupture. Further studies are necessary to determine if PAPP-A can represents a new target for stratifying the risk of cerebrovascular events.

Abstract: Vessel perforation is an uncommon but potentially life-threatening complication of percutaneous coronary intervention and is often associated with the use of atheroablative devices. While effective management means are currently available, such as PTFE-covered stent, pericardiocentesis, and perfusion balloon, a timely and skillful approach is of paramount importance to solve this dreadful complication. We hereby describe a case of saphenous vein graft (SVG) perforation occurring after cutting balloon angioplasty for in-stent restenosis. Despite the immediate occurrence of cardiac arrest due to massive extravasation of contrast in the mediastinum with pericardial tamponade, deep catheter intubation enabled the deployment of two PTFE-covered stents and subsequent sealing of the leak with repeated inflation of a perfusion balloon, while hemopericardium was drained by pericardiocentesis. This clinical vignette emphasizes the role of optimal backup in order to deploy life-saving devices and successfully manage life-threatening pericardial tamponade due to SVG rupture.

Abstract: OBJECTIVES: To compare long term outcomes of the crush versus the T technique in bifurcation lesions. DESIGN: 182 consecutive patients were identified who underwent percutaneous coronary interventions for bifurcation lesions with drug eluting stents between April 2002 and January 2004. Two techniques were used according to the operator's discretion: crush (group C, n = 121) or T (group T, n = 61). RESULTS: In-hospital outcome differed significantly between the two groups. Angiographic follow up was available for 142 (78%) patients. Groups C and T did not differ significantly regarding late loss (0.42 (0.39) mm v 0.34 (0.35) mm, p = 0.52) and rate of restenosis (16.2% v 13.0%, p = 0.80) in both the main and the side branch without final kissing balloon post-dilatation. However, when final kissing balloon post-dilatation was performed, group C had significantly lower late lumen loss (0.23 (0.21) mm v 0.37 (0.33) mm, p = 0.02) and restenosis rate (8.6% v 26.5%, p = 0.04) in the side branch. At one year's clinical follow up, group C compared with group T had lower rates of target lesion revascularisation (14.0% v 31.1%, p = 0.01) and target vessel revascularisation (16.5% v 32.8%, p = 0.02). CONCLUSIONS: In non-selected bifurcation lesions treated with drug eluting stents, the restenosis rate remains relatively high in the side branch. Compared with the T stenting technique, crush stenting with kissing balloon post-dilatation is associated with a reduced rate of restenosis in the side branch.

Abstract: BACKGROUND: Improvements in results with percutaneous coronary intervention (PCI) with drug-eluting stents (DES) may extend their use in patients with left main coronary artery (LMCA) stenosis. METHODS AND RESULTS: Two hundred forty-nine patients with LMCA stenosis were treated with PCI and DES implantation (n=107) or coronary artery bypass grafting (CABG) (n=142), in a single center, between March 2002 and July 2004. A propensity analysis was performed to adjust for baseline differences between the two cohorts. At 1 year, there was no statistical difference in the occurrence of death in PCI versus CABG both for the unadjusted (OR=0.291; 95% CI=0.054 to 1.085; P=0.0710) and adjusted analyses (OR=0.331; 95% CI=0.055 to 1.404; P=0.1673). PCI was correlated to a lower occurrence of the composite end points of death and myocardial infarction (unadjusted OR=0.235; 95% CI=0.048 to 0.580; P=0.0002; adjusted OR=0.260; 95% CI=0.078 to 0.597; P=0.0005) and death, myocardial infarction, and cerebrovascular events (unadjusted OR=0.300; 95% CI=0.102 to 0.617; P=0.0004; adjusted OR=0.385; 95% CI=0.180 to 0.819; P=0.01). No difference was detected in the occurrence of major adverse cardiac and cerebrovascular event at the unadjusted (OR=0.675; 95% CI=0.371 to 1.189; P=0.1891) and adjusted analyses (OR=0.568; 95% CI=0.229 to 1.344; P=0.2266). CONCLUSIONS: At 1 year, in this single-center, retrospective experience, there was no difference in the degree of protection against death, stroke, myocardial infarction, and revascularization between PCI with DES and CABG for LMCA disease.

Abstract: INTRODUCTION: Gradual prolonged balloon angioplasty may cause less arterial trauma, higher success rates, and fewer complications than conventional angioplasty (POBA). The OFFAR aimed to determine the safety and effectiveness of the FX MiniRAIL (FX) catheter, used with a slow, stepwise inflation protocol. METHODS AND RESULTS: From June to December 2003, 181 consecutive patients (age 61.9 +/- 10.6 years) with de novo coronary artery lesions (n = 217) were treated by FX and stent implantation in 11 European centers. Fifty-one patients (28.2%) had diabetes, and 70 (38.7%) had prior MI; 73 patients (40.3%) presented with stable angina and 85 (47.0%) with unstable angina. Fifty-five lesions (25.3%) were in small vessels (<2.5 mm), 40 (18.6%) were highly calcific, and 133 (62%) were long lesions (>18 mm). Stenosis resolution pressure was 7.17 +/- 4.2 atm; inflation time was 116.5 +/- 54.6 seconds. FX technical success (residual stenosis <50% post-FX) was obtained in 191 lesions (88.0%), and FX optimal success (residual stenosis <20% post-FX) in 117 (54.9%). Dissection was observed in 34 lesions (15.9%), 27 (79.3%) of which were type A or B. No coronary ruptures occurred. Nine (5.0%) in-hospital events occurred, all non-Q-wave MI. During 6-month follow-up, major adverse clinical events occurred in 14.4% of cases (n = 26; 3 cardiac deaths, 1 Q-wave MI, 2 non-Q-wave MI, 3 CABG, and 17 re-PTCA). CONCLUSION: The results of the OFFAR suggest that FX utilization for treatment of de novo complex coronary lesions is safe and effective.

Abstract: The instability of atherosclerotic plaque is partly determined by local factors, but systemic factors such as infection, inflammation, autoimmunity or genes might also be important. We aimed to analyze whether patients with acute myocardial infarction (AMI) might have a higher proportion of unstable plaques in the carotid arteries compared with patients who had had no acute coronary events. METHODS: Sixty-nine consecutive patients with AMI (Group 1) and 95 patients without acute coronary events (Group 2) had carotid artery duplex ultrasounds. Carotid atherosclerosis was quantified by number of plaques in the two carotid arteries, intimal media thickening and degree of maximal stenosis. According to their morphology, plaques were divided into stable (fibrocalcific) and unstable (soft and/or not homogeneous). RESULTS: The two groups did not differ as regards age (66+/-8 vs. 68+/-19; p=0.3), female sex (13% vs. 21%; p=0.3), mean number of carotid plaques (2.8+/-1 vs. 2.5+/-2; p=0.2), degree of stenosis (59+/-2% vs. 36+/-1%; p=0.2) or intimal media thickening (1.04+/-0.2 vs. 1.06+/-0.2; p=0.8). However, Group 1 pts more frequently had unstable carotid plaques compared with Group 2 (43% vs. 15%; p=0.004), and had a greater number of unstable carotid plaques (0.51+/-0.6 vs. 0.16+/-0.4: p<0.0001) and a higher ratio of unstable to stable plaque (19% vs. 8%; p=0.005). In the overall population, logistic regression analysis showed that after adjustment for degree of maximal stenosis, the presence of coronary artery event (AMI pts) predicted the presence of unstable carotid plaque (OR: 4.3 95% CI: 2.0-9.2; p=0.0002). CONCLUSION: Patients with unstable coronary artery disease expressed clinically as AMI, frequently had unstable atherosclerotic plaques in other arterial sites such as carotid arteries. This finding supports the hypothesis that plaque instability might reflect a systemic process.

Abstract: OBJECTIVES: Aortic dissection is characterized by an acute phase of medial dissection and a subacute-chronic phase of vessel wall repair. Matrix metalloproteinases (MMPs), through degradation of extracellular matrix, may play an important role in these processes. Elevation of MMPs might represent an opportunity to diagnostically characterize acute or chronic aortic processes. We examined the potential diagnostic role of MMP-9 and MMP-2 in different phases of aortic dissection. METHODS: Plasma levels of MMPs were evaluated by enzyme-linked immunosorbent assay technique in 13 patients affected by acute aortic dissection (nine type A, four type B). Ten healthy subjects were used as controls. In patients with type B aortic dissection treated medically, plasma curves (1, 3, 6, 12, 24, 48 and 96 h; 1 and 2 weeks; and 2 months from symptom onset) were also assessed. Aortic tissue samples obtained during surgery were evaluated by immunohistochemistry and western blot for MM-9 and tissue inhibitor of metalloproteinase-1 expression. RESULTS: MMP-9 plasma levels were increased in patients affected by type A and type B aortic dissection presenting within 1 h from onset of symptoms compared to controls (29.3 +/- 16.1 and 16.7 +/- 2.1 ng/ml versus 7.74 +/- 1.6 ng/ml, P < 0.03, respectively). No differences were detected in MMP-2 plasma levels compared to controls (4.84 +/- 1.2 ng/ml for type A and 6.16 +/- 0.6 ng/ml versus 3.17 +/- 1.0 ng/ml for controls, P = NS, respectively). In type B aortic dissection, mean MMP-9 plasma levels increased significantly from hospital admission to 2-month follow-up (16.7 +/- 2.1 ng/ml versus 58.0 +/- 8.2 ng/ml, P < 0.0001). Conversely, no difference in MMP-2 plasma levels was evident during follow-up (6.16 +/- 0.6 ng/ml versus 4.28 +/- 0.4 ng/ml, P = NS, respectively). Low-moderate (+/++) expression of MMP-9 was evident at immunohistochemistry in the acute phase whereas a marked expression (++++) was detected in the subacute phase. CONCLUSIONS: This pilot study suggests that the acute and subacute phase of both type A and type B aortic dissection is characterized by an increase of MMP-9 plasma levels. A marked increase is also evident in the subacute phase of medically treated type B aortic dissection as an expression of aortic wall remodelling. An increase of proteolytic activity could accompany attempts of the dissected aorta to heal itself but such a phenomena might further weaken the aortic wall, predisposing it to dilation and/or rupture.

Abstract: OBJECTIVES: To describe a novel approach to drug-eluting stent (DES) implantation, the sandwich technique, comprised of the simultaneous implantation of two completely overlapping DES in the same target lesion. BACKGROUND: DES effectively prevent restenosis in selected coronary lesions. However, adverse lesion characteristics may detrimentally affect outcomes after DES implantation by means of plaque prolapse, recoil or excessive neointimal hyperplasia. METHODS: From July 2002 to November 2004, the sandwich technique was performed in 10 patients with very high-risk lesions. Two DES of identical size and length were implanted, one inside the other, with almost complete overlap. High-pressure postdilatation (up to 28 atm) was carried out in 6 cases. The endpoints of this preliminary evaluation were: technical feasibility, early (30-day) safety, restenosis rate and freedom from adverse events at 9-month follow up. RESULTS: Procedural and angiographic success was achieved in all cases. At follow-up, there were no deaths, myocardial infarctions or stent thromboses. All patients underwent angiographic follow-up; target lesion revascularization was carried out in 3 patients (30%). Of note, in no case was there evidence of aneurysmal remodeling. CONCLUSIONS: This study suggests that implanting 2 DES, one inside the other in a sandwich fashion, is feasible and apparently safe. This approach could be considered in situations such as plaque prolapse or stent recoil where additional scaffolding may be needed.

Abstract: BACKGROUND: Elective intraaortic balloon pump (IABP) may reduce acute complications during unprotected left main (ULM) stenting. However, few data exist on criteria for elective IABP support during ULM stenting. METHODS: Since January 1993, 219 consecutive patients underwent elective ULM stenting: 69 had elective IABP support (elective IABP group), whereas 150 patients had conventional procedure (conservative group). Criteria for elective IABP support were (1) lesion located in the distal segment of the left main (bifurcation lesion), (2) left ventricular ejection fraction <40%, (3) atherectomy, (4) unstable angina, and (5) critical disease of the right coronary artery. Incidence of intraprocedural major adverse cardiac events (eg, severe hypotension and/or shock, myocardial infarction, urgent bypass surgery, and death) was assessed. RESULTS: Euroscore >6 (identifying high-risk patients) occurred in 38% in the elective IABP group and 13% in the conservative group (P < .001). Severe hemodynamic instability occurred in 12 patients (8%) in the conservative group and in none in the elective IABP group (P = .020). Intraprocedural major adverse cardiac event was higher in the conservative group (9.5% vs 1.5%, P = .032). Elective IABP support (OR 0.08, 95% CI 0.01-0.69, P = .022) and presence of Euroscore >6 plus bifurcation lesion (OR 5.49; 95% CI 1.47-20.51; P = .011) were the independent predictors of intraprocedural events. CONCLUSIONS: Elective IABP may prevent intraprocedural events in elective ULM stenting, especially in patients at higher risk.

Abstract: Thienopyridines and aspirin are beneficial in patients undergoing bare-metal stent implantation, and aspirin and clopidogrel treatment have also been proved effective after drug-eluting stent (DES) implantation. However, despite the common substitution of clopidogrel with ticlopidine because of cost or patient intolerance, there are no data on the comparison of ticlopidine vs. clopidogrel after DES implantation. We hereby compare ticlopidine vs. clopidogrel after paclitaxel-eluting stent implantation in subjects enrolled in the prospective multicenter Taxus in Real-life Usage Evaluation (TRUE) Study. Across the 505 analyzed patients (112 treated with ticlopidine and 393 with clopidogrel), similar rates of early and mid-term (7 months) adverse thrombotic events were found with either antiplatelet regimen, with the notable exception of 2 cases of late stent thrombosis in patients who had prematurely withdrawn ticlopidine treatment just 3 months after the procedure. These findings thus support the overall safety and effectiveness of ticlopidine after DES implantation, and also confirm the increased risk of late thrombosis when premature withdrawal of thienopyridines occurs.

Abstract: AIM: To evaluate patterns of restenosis following implantation of sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) in comparable unselected lesions. METHODS AND RESULTS: We have identified all episodes of restenosis after SES or PES implantation in our institutions between March 2003 and March 2005. Restenosis pattern was classified as focal, diffuse, proliferative, or occlusive. The position of focal restenosis was also categorized as proximal, in-stent, distal, or multi-focal. We have characterized 150 and 149 restenotic lesions in SES and PES groups, respectively. The incidence of diffuse and occlusive restenosis was significantly higher in PES than in SES (47.6 vs. 27.0%, P < 0.001). Multivariable (OR 2.693, 95% CI 1.425-5.089, P = 0.002) and propensity (OR 3.00, 95% CI 1.584-5.672, P < 0.001) analyses confirmed the positive association of PES with non-focal restenosis. For both stents, focal-edge restenosis was significantly more likely to occur proximally than distally (61.0 vs. 16.9%, P < 0.001 for PES and 45.8 vs. 16.8%, P < 0.001 for SES). CONCLUSION: Focal restenosis remains the most common pattern with SES. In contrast, just under half of restenosis in PES is the more severe non-focal pattern. Paradoxically, the majority of focal restenosis occurs at the proximal stent margin for both platforms.

Abstract: Drug-eluting stents have been unequivocally demonstrated to reduce in-stent restenosis when compared to bare metal stents, with resultant lower rates of repeat revascularization. Comparative data are now emerging which compare the performance of sirolimus- and paclitaxel-eluting stents to each other rather than to bare metal stents. In this article, we review these data with the aim of placing the studies in context thereby providing an overall view of this rapidly developing field as it stands at present.

Abstract: OBJECTIVES: We sought to determine if the angiographic pattern of in-stent restenosis in drug-eluting stents (DES) maintains its prognostic importance. BACKGROUND: The pattern of restenosis in the bare-metal stent era had a significant impact on therapeutic outcomes. METHODS: We identified a total of 250 consecutive restenotic lesions in 203 patients (66.4% sirolimus-eluting stents and 33.6% paclitaxel-eluting stents). We divided these lesions into two groups: focal, defined as < or =10 mm, 163 lesions (65.2%); and nonfocal, which were diffuse, proliferative, or obstructive, 87 lesions (34.8%). The end points analyzed were angiographic restenosis and target lesion revascularization (TLR). RESULTS: Diabetes was the only clinical variable associated with the pattern of restenosis (28.8% focal compared with 52.9% diffuse; p = 0.0001). Angiographic follow-up of the treatment of restenosis was available in 61.2% of the lesions and was similar between the two groups. The rate of angiographic restenosis was 17.8% in the focal group and 51.1% in the nonfocal group (p = 0.0001). The incidence of TLR also increased with the type of restenosis treated (9.8% and 23%, respectively; p = 0.007). An adjusted multivariate analysis revealed that the pattern of restenosis remained associated with both the occurrence of restenosis and TLR (odds ratio [OR] 5.1 [95% confidence interval (CI) 1.1 to 23], p = 0.03; and OR 3.61 [95% CI 1.2 to 10.9], p = 0.02; respectively). CONCLUSIONS: Similar to bare-metal stent data, the angiographic pattern of restenosis following DES implantation is prognostically important. Diabetes is a significant predictor of the pattern of restenosis in the DES era.

Abstract: OBJECTIVES: To evaluate safety and efficacy of the CROSSER CTO Recanalization System (CROSSER). BACKGROUND: The CROSSER, a novel device dedicated to recanalization of chronic total occlusions (CTO), relies on a monorail catheter delivering vibrational energy to facilitate the crossing of occluded coronary arteries. METHODS: We included de novo or restenotic occlusions in native coronary arteries with typically unfavorable characteristics and a prior failed guidewire attempt either performed in a previous procedure or just before the usage of the CROSSER. The end points analyzed were technical success (ability to cross or facilitate a guidewire crossing into the true lumen), angiographic success (<20% residual stenosis and TIMI flow grade 3), and clinical success (angiographic success and freedom from major adverse cardiac events at 30 days). RESULTS: Twenty-eight patients (30 lesions) were included. The morphology was blunt in 83.3% and the length of the occlusion was >20 mm in 76.6%. The median age of the CTO was 9 months (range 3-60 months). Technical success was obtained in 19 (63%) occlusions and angiographic success in 16 (53%): 26.3% in lesions with prior procedural failure and 73.7% when CROSSER was attempted after initial guidewire failure. Complications were: one guidewire perforation without consequences and one peri-procedural myocardial infarction (MI). No events occurred within 30-day follow-up after discharge. CONCLUSIONS: In our experience, the CROSSER System is safe and increases the success of opening CTO refractory to guidewires. This novel device may represent an useful adjunct to the armamentarium of the interventional cardiologist.

Abstract: In patients with in-stent restenosis (ISR) inside bare metal stents, drug-eluting stents reduce the recurrence of restenosis compared with balloon angioplasty. However, few data are available about this therapeutic modality in the case of diffuse restenosis. The aim of this study was to evaluate the immediate and mid-term outcome of sirolimus- and paclitaxel-eluting stent implantation in diffuse ISR and determine the predictors of clinical and angiographic restenosis recurrence. A series of 161 consecutive patients with 194 diffuse ISR lesions (>10 mm) treated with drug-eluting stent implantation were evaluated. Major adverse cardiac events were defined as death, myocardial infarction, and the need for target lesion revascularization. During a mean follow-up of 8.2 +/- 3.4 months, the cumulative incidence of major adverse cardiac events was 19% in the SES group and 24% in the PES group (p = 0.56). Angiographic follow-up was performed in 80% of the lesions. The overall restenosis rate was 22% and was not significantly different between lesions treated with sirolimus-eluting (20%) or paclitaxel-eluting (25%, p = 0.55) stents. The incidence of restenosis was higher in diabetics (32%) than in nondiabetics (16%, odds ratio 2.5, 95% confidence interval 1.1 to 5.5, p = 0.02). By multivariate analysis, diabetes was confirmed to be the only independent predictor of recurrent restenosis (odds ratio 3.53, 95% confidence interval 1.39 to 9.02, p = 0.008). In conclusion, drug-eluting stent implantation for diffuse ISR is associated with acceptable clinical and angiographic results. The association of diffuse restenosis and diabetes mellitus is an unfavorable condition leading to a high risk of recurrence.

Abstract: AIMS: Coronary dissections left untreated after percutaneous coronary intervention are associated with unfavourable outcomes. However, their role after drug-eluting stent (DES) implantation is still undescribed. We assessed incidence, predictors, and outcomes of residual dissections in DES-treated lesions. METHODS AND RESULTS: Consecutive patients undergoing DES implantation were enrolled in four Italian centres, with baseline, procedural, and outcome data entered into a dedicated database. Residual dissections were classified according to the National Heart Lung and Blood Institute criteria. End-points of interest were in-hospital, 1-month, and 6-month major adverse cardiovascular events (MACE, i.e. death, myocardial infarction, or target vessel revascularization), and stent thrombosis (ST). Among the 2418 included patients (4630 lesions), a total of 77 (1.7%) final dissections occurred in 67 (2.8%) subjects. Dissections were more frequent in longer and complex lesions and in the left anterior descending, and were associated with increased rates of in-hospital (11.9 vs. 5.2%, P=0.017) and 1-month MACE (13.4 vs. 6.0%, P=0.013), with similar 6-month trends. Cumulative ST was also greater in patients with dissections (6.3 vs. 1.3%, P=0.011). Even non-obstructive dissections with thrombolysis in myocardial infarction 3 flow conferred a significantly worse prognosis. CONCLUSION: This study, reporting for the first time on incidence, predictors, and outcomes of residual dissections in DES-treated coronary lesions, demonstrates their adverse clinical impact and supports the pursuit of a strategy of sealing dissection flaps with other DES.

Abstract:

Abstract: OBJECTIVES: The purpose of this study was to evaluate predictors of an adverse outcome after "crush" bifurcation stenting. BACKGROUND: The "crush" technique is a recently introduced strategy with limited data regarding long-term outcomes. METHODS: We identified 231 consecutive patients treated with drug-eluting stent implantation with the "crush" technique for 241 de novo bifurcation lesions. Clinical follow-up was obtained in 99.6%. RESULTS: The in-hospital major adverse cardiac event (MACE) rate was 5.2%. At 9 months, 10 (4.3%) patients had an event consistent with possible post-procedural stent thrombosis. Survival free of target lesion revascularization (TLR) was 90.3%; the only independent predictor of TLR was left main stem (LMS) therapy (odds ratio [OR] 4.97; 95% confidence interval [CI] 2.00 to 12.37, p = 0.001). Survival free of MACE was 83.5% and independent predictors of MACE were LMS therapy (OR 3.79; 95% CI 1.76 to 8.14, p = 0.001) and treatment of patients with multivessel disease (OR 4.21; 95% CI 0.95 to 18.56, p = 0.058). Angiographic follow-up was obtained in 77% of lesions at 8.3 +/- 3.7 months. The mean late loss of the main vessel and side branch were 0.30 +/- 0.64 mm and 0.41 +/- 0.67 mm, respectively, with binary restenosis rates of 9.1% and 25.3%. Kissing balloon post-dilation significantly reduced the side branch late lumen loss (0.24 +/- 0.50 mm vs. 0.58 +/- 0.77 mm, p < 0.001). CONCLUSIONS: The crush technique of bifurcation stenting with drug-eluting stents is associated with favorable outcomes for most lesions; however, efficacy appears significantly reduced in LMS bifurcations, and further research is needed before the technique can be routinely recommended in this group. Furthermore, the incidence of possible stent thrombosis is of concern and requires further investigation. Kissing balloon post-dilatation is mandatory to reduce side branch restenosis.

Abstract:

Abstract: The complications concerning liver and intestinal transplant surgery have relevance for the field of intensive care because they share some characteristics with those following complex long-term surgery. Thus, in this article we shall try to describe complications that are specific to liver and multivisceral transplants. A review of the existing literature on this topic reveals a large number of studies dedicated to early as well as late surgical complications, and immunosuppressive treatment, while there are far fewer contributions describing complications exclusively concerning intensive care. We shall thus attempt to focus on certain aspects where, besides the literature data, we have personal experience. In particular we want to underline the implications of failure in the functional recovery of the graft; alterations in water, electrolyte, and glycemic balance; as well as neurological, respiratory, renal, nutritional, and infective complications.

Abstract: The novel device Frontrunner coronary catheter (FCC), dedicated to recanalization of chronic total occlusions (CTOs), relies on blunt microdissections inside the plaque, allowing passage of guidewire through the lesion and adjunctive angioplasty. In order to evaluate efficacy and safety of recanalization using the FCC device, we included patients with de novo or restenotic CTOs in a native coronary artery with prior failure using a guidewire or considered unsuitable for guidewire attempt in which the FCC was attempted first. Between October 2000 and June 2003, 50 patients with 50 CTOs were included in the study. Thirty-two patients had prior failure with a mechanical wire. Device and angiographic success were obtained in 25 (50%) occlusions: 53% in lesions with prior guidewire failure and 44% when FCCs were attempted first (P = 0.8). During the first year of experience, angiographic success was 42% (5 occlusions) and in the third year 75% (12 occlusions; P = 0.12). Coronary perforation occurred in nine (18.0%) patients, leading to tamponade in two (4%) patients. Perforations occurred in 5 out of 12 attempted patients during the first year and in 4 out of 38 patients in the following period (41.7% vs. 10.5%; P = 0.04). Serious adverse events occurred in five (10%) patients within 30-day follow-up. Four non-Q-wave myocardial infarctions occurred in hospital (clinical success 42%) and one death 7 days after the index procedure. The use of FCC increases the success to open chronic total occlusions refractory to mechanical guidewires or that were considered unsuitable for an attempt with a guidewire. The risk of coronary perforation due to FCC use is relatively high and it can decrease with experience.

Abstract: BACKGROUND: Recent data support that iodixanol, an iso-osmolality contrast agent, is less nephrotoxic than low-osmolality contrast agents when hydration is the only prophylactic strategy used. We evaluated the nephrotoxicity of iso- and low-osmolality contrast agents with prophylactic administration of N-acetylcysteine (NAC) along with hydration. METHODS: Two hundred and twenty-five patients with chronic renal insufficiency (serum creatinine >1.5 mg/dL or an estimated glomerular filtration rate <60 mL/min/1.73 m(2)), referred to our institution for coronary and/or peripheral procedures, were assigned to receive low-osmolality (iobitridol group; N = 115) or iso-osmolality (iodixanol group; N = 110) contrast dye. In all cases prophylactic administration of 0.45% saline intravenously and NAC (1200 mg orally twice daily) was used. RESULTS: Baseline creatinine levels were similar in the 2 groups [iobitridol group = 1.70 (IQR: 1.54-1.98) mg/dL; iodixanol group = 1.73 (IQR: 1.56-2.00) mg/dL, P = 0.33]. The risk score for contrast nephrotoxicity was 5.0 +/- 1.6 in the iobitridol group versus 5.0 +/- 1.8 in the iodixanol group (P = 0.44). Increase of at least 0.5 mg/dL of the creatinine concentration 48 hours after the procedure occurred in 4/115 patients (3.5%) in the iobitridol group and 3/110 patients (2.7%) in the iodixanol group (P = 1.00; OR 0.78; 95% CI 0.17-3.56). Amount of contrast media administration was similar in the 2 groups (iobitridol group = 167 +/- 90 mL; iodixanol group = 164 +/- 82 mL; P = 0.61). CONCLUSION: Nephrotoxicity of iso-osmolality and low-osmolality contrast agents was similar when a prophylactic strategy of hydration plus NAC was utilized.

Abstract: Extracellular proteolysis plays a key role in many pathophysiologic processes including cancer, inflammatory diseases, and cardiovascular conditions such as atherosclerosis and restenosis. Whereas matrix metalloproteinases are their best known member, many others are becoming better known. The extracellular proteases are a complex and heterogeneous superfamily of enzymes. They include metalloproteinases (matrix metalloproteinases, adamalysins, or pappalysins), serine proteases (elastase, coagulation factors, plasmin, tissue plasminogen activator, urokinase plasminogen activator), and the cysteine proteases (such cathepsins). In addition to their matrix degradation capabilities, they have other less well known biologic functions that include angiogenesis, growth factor bioavailability, cytokine modulation, receptor shedding, enhancing cell migration, proliferation, invasion, and apoptosis. This review discusses extracellular proteases relevant to the vasculature, their classification and function, and how protease disorders contribute to arterial plaque growth, including chronic atherosclerosis, acute coronary syndromes, restenosis, and vascular remodeling. These broad extracellular protease functions make them potentially interesting therapeutic targets.

Abstract: From experimental and clinical studies it is known that matrix conservation and degradation by matrix metalloproteinases (MMPs) plays a major role in plaque progression and destabilization with related onset of acute vascular events such as acute coronary syndromes or cerebrovascular accidents. Recently, extracellular MMPs inducer (EMMPRIN) has been reported to induce and activate the expression of MMPs in myocardium and plays an important role in the ventricular remodeling in human heart failure. Similarly to heart failure myocardium, EMMPRIN may be expressed in human atheroma and play a role in the extracellular matrix (ECM) remodeling and atherogenic cell differentiation. This study was designed to investigate the possible biological role of EMMPRIN in human atheroma. Immunohistochemical analysis for MMPs and EMMPRIN was performed on human carotid endarterectomy specimens and control aortas. EMMPRIN showed significant immunoreactivity in human atherosclerotic carotid lesions, and was colocalized with macrophage/monocyte infiltrates in atherosclerotic intima, plaque itself and vascular smooth muscle cells (VSMCs). Zymography and Western blot analysis revealed EMMPRIN expression in the carotid atheromas, but not in the control aortas. Human bone marrow monocytes, which were cultured with atherogenic proinflammatory cytokine stimulation revealed increased EMMPRIN and MMPs expressions. ECM remodeling is under the control of induction and inhibition of matrix degrading protease and the novel MMP inducer, EMMPRIN may play a role in influx and differentiation of monocytes and destabilizing atheroma.

Abstract: OBJECTIVES: This study was undertaken to define and compare geographic coronary artery inflammation in patients who were dying of acute myocardial infarction (AMI), chronic stable angina (SA), and noncardiac causes (CTRL). BACKGROUND: Biochemical markers and flow cytometry provide indirect evidence of diffuse coronary inflammation in patients dying of acute coronary syndromes. Yet no histopathologic studies have corroborated these findings. A key unanswered question is whether the inflammatory burden involves the entire coronary tree or is limited to a few plaques. METHODS: We examined 544 coronary artery segments from 16 patients with AMI, 109 segments from 5 patients with SA, and 304 coronary segments from 9 patients with CTRL. RESULTS: An average of 6.8 +/- 0.5 vulnerable segments per patient were found in the AMI group (in addition to culprit lesions) compared with an average of 0.8 +/- 0.3 and 1.4 +/- 0.3 vulnerable lesions/patient in the SA and CTRL groups, respectively. The AMI group, independent of the type of plaque observed, showed significantly more inflammatory infiltrates compared with the SA and CTRL groups (121.6 +/- 12.4 cell x mm2 vs. 37.3 +/- 11.9 cell x mm2 vs. 26.6 +/- 6.8 cell x mm2, p = 0.0001). In AMI patients, active inflammation was not only evident within the culprit lesion and vulnerable plaques but also involved stable plaques. These showed a three- to four-fold higher inflammation than vulnerable and stable plaques from the SA and CTRL groups, respectively. CONCLUSIONS: This histopathologic study found that both vulnerable and stable coronary plaques of patients dying of AMI are diffusely infiltrated by inflammatory cells.

Abstract: Several studies with drug-eluting stents (DES) have demonstrated dramatic reductions in restenosis rates compared with bare metal stents (BMS). Although the clinical benefits of DES are increasingly evident, important concerns about their costs have been raised. Most data regarding the impact of restenosis on long-term costs after percutaneous coronary intervention (PCI) are derived from clinical trials. These studies demonstrate that there is no single cost or economic burden of restenosis; these values vary substantially according to the specific patient population under investigation and to the healthcare system reality where they are applied. In the present study we propose an economic interactive decision model which was applied to the Italian healthcare system, considering the different reimbursement rates of the Italian regions for DES and for both PCI and coronary artery bypass surgical interventions (CABG). The aim of this model was to simulate the impact of DES introduction after potential complete reimbursement by the national healthcare system, hypothesizing the usage of 1.4 stent per patient in case of single vessel disease and 2.4 stents in case of multivessel disease, and utilizing the TAXUS IV rate of revascularization for reintervention costs calculation and the ARTS-I study for CABG costs. For a low risk patients' population, the mean cost of a procedure with DES was 6% greater than utilizing BMS (xi 8125 for DES vs xi 7651 for BMS). However, this percentage was reduced in case of diabetic patients (+4%), long lesions (+2%) and was favourable for small vessels (-3%). In addition, in case of multivessel disease with conversion from CABG to DES, the 12 months cost per patients was reduced of around 30% (xi 10 170 for PCI vs xi 14 584 for CABG). This model suggests that national healthcare system may save 2.1% of the total costs (xi 18.60 millions) if 60% of revascularization procedures converts to total DES utilization and 15% from CABG to PCI with DES.

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Abstract: CONTEXT: Traditionally, stent thrombosis has been regarded as a complication of percutaneous coronary interventions during the first 30 postprocedural days. However, delayed endothelialization associated with the implantation of drug-eluting stents may extend the risk of thrombosis beyond 30 days. Data are limited regarding the risks and the impact of this phenomenon outside clinical trials. OBJECTIVE: To evaluate the incidence, predictors, and clinical outcome of stent thrombosis after implantation of sirolimus-eluting and paclitaxel-eluting stents in routine clinical practice. DESIGN, SETTING, AND PATIENTS: Prospective observational cohort study conducted at 1 academic hospital and 2 community hospitals in Germany and Italy. A total of 2229 consecutive patients underwent successful implantation of sirolimus-eluting (1062 patients, 1996 lesions, 2272 stents) or paclitaxel-eluting (1167 patients, 1801 lesions, 2223 stents) stents between April 2002 and January 2004. INTERVENTIONS: Implantation of a drug-eluting stent (sirolimus or paclitaxel). All patients were pretreated with ticlopidine or clopidogrel and aspirin. Aspirin was continued indefinitely and clopidogrel or ticlopidine for at least 3 months after sirolimus-eluting and for at least 6 months after paclitaxel-eluting stent implantation. MAIN OUTCOME MEASURES: Subacute thrombosis (from procedure end through 30 days), late thrombosis (>30 days), and cumulative stent thrombosis. RESULTS: At 9-month follow-up, 29 patients (1.3%) had stent thrombosis (9 [0.8%] with sirolimus and 20 [1.7%] with paclitaxel; P = .09). Fourteen patients had subacute thrombosis (0.6%) and 15 patients had late thrombosis (0.7%). Among these 29 patients, 13 died (case fatality rate, 45%). Independent predictors of stent thrombosis were premature antiplatelet therapy discontinuation (hazard ratio [HR], 89.78; 95% CI, 29.90-269.60; P<.001), renal failure (HR, 6.49; 95% CI, 2.60-16.15; P<.001), bifurcation lesions (HR, 6.42; 95% CI, 2.93-14.07; P<.001), diabetes (HR, 3.71; 95% CI, 1.74-7.89; P = .001), and a lower ejection fraction (HR, 1.09; 95% CI, 1.05-1.36; P<.001 for each 10% decrease). CONCLUSIONS: The cumulative incidence of stent thrombosis 9 months after successful drug-eluting stent implantation in consecutive "real-world" patients was substantially higher than the rate reported in clinical trials. Premature antiplatelet therapy discontinuation, renal failure, bifurcation lesions, diabetes, and low ejection fraction were identified as predictors of thrombotic events.

Abstract: AIMS: To evaluate the outcomes of sirolimus-eluting stent (SES) implantation for the treatment of chronic total occlusion (CTO). METHODS AND RESULTS: We identified 122 patients who underwent revascularization in CTO lesions with SES from April 2002 to April 2004 (SES group). A control group was composed of 259 consecutive patients with CTO lesions treated with bare metal stents (BMS) in the 24 months immediately before the introduction of SES (BMS group). At 6-month follow-up, the cumulative rate of major adverse cardiac events (MACE) was 16.4% in the SES group and 35.1% in the BMS group (P<0.001). The incidence of restenosis was 9.2% in the SES group and 33.3% in the BMS group (P<0.001). The need for revascularization in the SES group was significantly lower, both target lesion revascularization (7.4 vs. 26.3%, P<0.001) and target vessel revascularization (9.0 vs. 29.0%, P<0.001). BMS implantation (HR: 2.97; 95% CI: 1.80-4.89; P<0.001), lesion length (>20 mm) (HR: 2.02; 95% CI: 1.37-2.99; P=0.0004), and baseline reference vessel diameter (>2.8 mm) (HR: 0.62; 95% CI: 0.42-0.92; P=0.02) were identified as predictors of MACE during 6-month follow-up. CONCLUSION: Compared with BMS, SES implantation in CTO lesions appears to be effective in reducing the incidence of restenosis and the need for revascularization at 6 months.

Abstract: OBJECTIVES: The purpose of the present report was to evaluate clinical and angiographic outcomes of drug-eluting stent (DES) implantation in saphenous vein graft (SVG) lesions. BACKGROUND: The safety and efficacy of DES implantation for the treatment SVG lesions remains uncertain. METHODS: We evaluated in-hospital and six-month outcomes in 61 consecutive patients treated with DES in SVG lesions from March 2002 to March 2004 (DES group), as compared to 89 consecutive patients treated with bare-metal stents (BMS) in the 24 months immediately before the introduction of DES (BMS group). Major adverse cardiac events (MACE) including death, myocardial infarction, target lesion revascularization (TLR), and target vessel revascularization (TVR) were recorded in-hospital and at six-month follow-up. RESULTS: The rate of in-hospital MACE was similar between the two groups (6.6% vs. 5.6%, p = 1.0). Cumulative MACE at six months was 11.5% in the DES group and 28.1% in the BMS group (p = 0.02). The DES group had a significantly lower incidence of in-segment restenosis (10.0% vs. 26.7%, p = 0.03), TLR (3.3% vs. 19.8%, p = 0.003), and TVR (4.9% vs. 23.1%, p = 0.003). By Cox regression analysis, diabetes (hazard ratio [HR]: 3.03; 95% confidence interval [CI]: 1.33 to 6.90; p = 0.008), usage of BMS (HR: 2.53; 95% CI: 1.07 to 5.97; p = 0.03), and age of SVG (HR: 1.10; 95% CI: 1.02 to 1.19; p = 0.02) were identified as predictors of MACE at six-month follow-up. CONCLUSIONS: Compared to BMS implantation, DES implantation in SVG lesions appears safe with favorable and improved mid-term outcomes.

Abstract: OBJECTIVES: We sought to determine the safety and efficacy of using multiple overlapping drug-eluting stents (DES) in patients with diffuse left anterior descending coronary artery (LAD) disease. BACKGROUND: Diffuse LAD disease represents a therapeutic challenge. Results after coronary artery bypass surgery are suboptimal, whereas the use of bare metal stents is limited by high rates of restenosis. The introduction of DES prompted treatment of long diffuse disease with multiple overlapping stents. METHODS: All consecutive patients with de novo diffuse LAD disease treated with more than 60-mm long DES from April 2002 to March 2004 were analyzed. RESULTS: The study population consisted of 66 patients. Thirty-nine patients were treated with sirolimus-eluting stents (SES), average length 84 +/- 22 mm, and 27 patients with paclitaxel-eluting stents (PES), average length 74 +/- 14 mm. The number of stents implanted per patient was 2.8 +/- 0.7, whereas the mean total stent length for the LAD treatment was 80 +/- 20 mm. Angiographic as well as procedural success was achieved in 95% of cases. Eleven (16.6%) patients had in-hospital non-Q-wave myocardial infarction (five SES and six PES), and one patient developed intraprocedural stent thrombosis. All patients had clinical follow-up, and 52 patients (79%) had an angiographic follow-up at six months. Hierarchical major adverse cardiac event rate was 15% (7.5% for SES and 7.5% for PES). No patients died, one patient had non-Q-wave myocardial infarction (non-index vessel), and 10 patients (15%) underwent target vessel revascularization. CONCLUSIONS: The implantation of multiple overlapping DES in patients with a diffusely diseased LAD is relatively safe and associated with good midterm clinical outcomes.

Abstract: Patients with severe calcific aortic stenosis are occasionally not amenable to surgery because of advanced age or severe co-morbidities. Percutaneous aortic valve dilation is used but has only limited time relief. While preclinical evidence on percutaneous aortic valve replacement seems promising, only very limited clinical data are available worldwide. We hereby present the first case of percutaneous aortic valve replacement successfully performed in Italy in a 74-year-old high-risk female. This case emphasizes the technical challenges inherent to this procedure and its promising role in selected very high-risk patients with severe aortic stenosis, notwithstanding the early and long-term risk of adverse events.

Abstract: OBJECTIVES: The purpose of this research was to evaluate the long-term outcomes after implantation of drug-eluting stents (DES) in bifurcation lesions with the "crush" technique. BACKGROUND: The long-term outcome of "crush" stenting technique has yet to be determined. METHODS: We identified 181 consecutive patients who were treated with DES with the "crush" stent technique from April 2002 to April 2004. Based on the usage of final kissing balloon post-dilation (FKB), the patients were divided into an FKB group (n = 116) and a non-FKB group (n = 65). RESULTS: Clinical follow-up at nine months was available in all patients, and angiographic follow-up in 80% of patients. Three cases (1.7%) of intraprocedural stent thrombosis and five (2.8%) cases of postprocedural stent thrombosis occurred. Restenosis rate of the main branch in the entire cohort lesions was 11.5%. Restenosis rate of the side branch was lower in the FKB group than that in the non-FKB group (11.1% vs. 37.9%, p < 0.001). The target lesion revascularization (TLR) rate for all patients was 14.9%. The lack of FKB was a predictor for TLR (hazard ratio [HR] 4.17; 95% confidence interval [CI] 1.30 to 14.3, p = 0.02). Diabetes was also a predictor for TLR (HR 1.79; 95% CI 1.14 to 2.80, p = 0.01). Premature discontinuation of dual antiplatelet therapy (odds ratio [OR] 16.8; 95% CI 1.31 to 159.5, p = 0.03) and age (OR 1.10; 95% CI 1.00 to 1.21, p = 0.048) was associated with the occurrence of postprocedural stent thrombosis. CONCLUSIONS: Compared to the absence of FKB, the "crush" stenting technique with FKB appears to be associated with more favorable long-term outcomes. When utilizing the "crush" stenting technique, FKB is mandatory.

Abstract: Although predictors of acute intraprocedural stent thrombosis (IPST) in the drug-eluting stent era have been proposed, external validation is lacking. We thus analyzed the occurrence of IPST in the RECIPE study and found that, among 1,320 patients who underwent drug-eluting stent implantation, IPST occurred in 6 (0.5%), with in-hospital major adverse events in 4 (67%). IPST was predicted by number and total length of implanted stents, baseline minimal lumen diameter, and, in a pooled analysis that incorporated values from the present study and a previous study, use of elective glycoprotein IIb/IIIa inhibitors. Such results may provide useful information to guide prevention of this complication.

Abstract: The aim of this study was to assess the safety and effectiveness of > or =4 sirolimus-eluting stent (SES; Cypher, Cordis, Johnson and Johnson) implantation. The safety of implantation of > or =4 SESs in the same patient and setting has not been established. Furthermore, it has been hypothesized that sirolimus administration with the use of multiple stents may diminish the platelet inhibitory effects of clopidogrel and may trigger drug-drug interactions. We identified 96 consecutive patients (96 procedures) who underwent implantation of > or =4 SESs in 365 lesions (438 stents) during the same procedure. All patients received aspirin indefinitely and clopidogrel or ticlopidine for at least 1 year postprocedure; 57% and 47% of the patients were on calcium channel blocker and statin therapy, respectively. All stents were successfully deployed and glycoprotein IIb/IIIa inhibitors were used in 50% of the procedures. There were no in-hospital deaths, Q-wave myocardial infarction (MI), urgent bypass surgery, or repeat percutaneous coronary intervention; 18 patients (19%) suffered non-Q-wave MI (defined as CK-MB elevation >3 times the upper limit of normal). At 30-day follow-up, there was one (1%) subacute thrombosis resulting in target lesion revascularization. At mean follow-up time of 15.4 +/- 6.2 months, the frequency of target lesion revascularization, target vessel revascularization, and major adverse cardiac event rates were 12%, 16%, and 18%, respectively. No other notable clinical events that might have been attributed to the possible drug-drug interactions or discontinuation of concomitant antithrombotic, statin, or calcium channel blocker therapy were reported. Multiple (> or =4) SES implantation appears safe with no increase in major adverse cardiac events.

Abstract: Successful recanalization of coronary total occlusions (CTOs) remains an area where improvements are needed. We propose an approach similar to the one utilized in treating some peripheral artery occlusions and aimed to create a subintimal dissection with distal reentry. A 0.014' hydrophilic wire with a J-configuration is utilized for this purpose. We applied this technique to CTO of native coronaries in 31 patients where previous attempts failed in 21 of them (67%). The right coronary artery (RCA) was the index vessel in 87% of patients. Recanalization of the vessel and of most of distal branches was achieved in 21 patients; patency of at least one major distal branch was achieved in 9 patients. Drug-eluting stents (DESs) were implanted in 53% of patients. Three patients had intraprocedural vessel perforation without consequences. Five patients (16%) had in-hospital non-Q-wave myocardial infarction. No other adverse events occurred at a mean follow-up of 5.1 +/- 3.7 months except for one noncardiac death. Angiographic follow-up was performed in 21 (67%) patients and 53% of them developed restenosis. Reintervention on the target vessel was performed in 11 patients (52%). Complete success with the procedure was originally obtained in 8 of the 10 patients who did not develop restenosis and in 8 of them DESs were originally implanted. This technique appears a promising approach to recanalize difficult total occlusions, particularly the ones localize on the RCA, which has the most important side branches located distally.

Abstract: Between April 2002 and May 2004, 174 consecutive patients who underwent percutaneous coronary intervention of bifurcational lesions with sirolimus-eluting stents were identified. Two strategies were used: stenting only 1 branch (group 1S, n = 57) or stenting both branches (group 2S, n = 117). The incidence of major adverse cardiac events was evaluated in the hospital and at 9-month follow-up. There were no statistically significant differences between the 2 groups with regard to the incidence of target lesion revascularization (5.4% vs 8.9%, p = 0.76), target vessel revascularization (5.4% vs 11.1%, p = 0.51), and cumulative major adverse cardiac events (18.9% vs 23.3%, p = 0.76) at 9 months.

Abstract: We compared the clinical efficacy of paclitaxel-eluting stents (PESs) and sirolimus-eluting stents (SESs) in a contemporary cohort of patients who had complex lesions. We collected data on 9-month outcomes in 529 patients (281 in the PES group and 248 in the SES group) whose de novo lesions were treated with drug-eluting stents. The end point was per-patient in-hospital and follow-up major adverse cardiac events, which were defined as a composite of death, myocardial infarction, and target vessel revascularization, including target lesion revascularization. There were no in-hospital deaths or repeat revascularizations; however, 5.7% of the PES group and 2% of the SES group developed a myocardial infarction (p = 0.04). At a median follow-up of 10.6 months, the rate of major adverse cardiac events was similar between groups (18.1% vs 21%, adjusted hazard ratio 0.85, 95% confidence interval 0.57 to 1.25), without any difference in the occurrence of death or myocardial infarction. Diabetes and total stent length were independent predictors of major adverse cardiac events. Propensity analysis confirmed the similarity between devices (hazard ratio 0.87, 95% confidence interval 0.62 to 1.25). Most restenoses were focal and only 2 patients required surgical revascularization. In conclusion, implantation of drug-eluting stents in complex lesions was associated with favorable results and most patients remained free from surgical revascularization at follow-up. Overall, the 2 available stent platforms had similar performance characteristics.

Abstract: We evaluated the safety and effectiveness of postdilating a 3.0 mm sirolimus-eluting stents (SESs; six cells) with a 3.5-4.0 mm balloon. We identified 254 consecutive patients who underwent percutaneous coronary interventions using SESs with a nominal diameter of 3.0 mm (six cells). Patients were divided into two groups based on whether they were subsequently postdilated with a 3.0 mm (group 1: 168 patients, 251 lesions) or a 3.5-4 mm balloon (group 2: 86 patients, 102 lesions). There were no significant differences regarding the incidence of in-hospital and long-term follow-up. Angiographic follow-up was available in 72% and 74% of groups 1 and 2, respectively. The two groups had no significant differences regarding late lumen loss (0.51 +/- 0.36 vs. 0.52 +/- 0.33; P = 0.3) and binary restenosis rates (10.7% vs. 8.8%; P = 0.1). Six-month clinical follow-up was available in all patients. At long-term follow-up (mean: 10.6 +/- 3.7 for group 1 and 11.3 +/- 3.9 months for group 2), there were no significant differences between the two groups regarding major adverse cardiac events (8.9% vs. 9.2%; P = 0.9). Implantation of a 3.0 mm SES with postdilation with a 3.5-4 mm balloon did not result in any significant difference in complications, in-hospital non-Q-wave myocardial infarction, binary restenosis, or target lesion revascularization. These data should lessen concern that overdilation may dilute the beneficial effects of SESs.

Abstract: We evaluated predictors of increased periprocedural creatine kinase-MB isoenzyme levels after implantation of sirolimus-eluting stents with an intent to fully cover the diseased segment. The total stent length per patient (predisposing factor) and elective use of glycoprotein IIb/IIIa (protective factor) were independent predictors of increased creatine kinase-MB isoenzyme levels.

Abstract: We sought to determine the incidence of coronary perforations, predisposing factors, and in-hospital and late outcome of patients with coronary perforations. Perforations occurred in 0.84% of treated lesions and more frequently in patients with complex lesions after atheroablative procedures and who underwent intravascular ultrasound guided lumen optimization. The incidence of adverse events, emergency coronary artery bypass grafting and death significantly decreased over time.

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Abstract: OBJECTIVES: This study evaluated clinical outcome after multivessel stenting with sirolimus-eluting stents (SES) in unselected lesions. BACKGROUND: Safety and effectiveness of multivessel SES implantation is currently unknown. METHODS: Major adverse cardiac events (MACE) (death, myocardial infarction [MI], and repeat revascularization) were analyzed at 30 days and at 6 months after multivessel SES implantation. RESULTS: In 155 consecutive patients, 573 SES were implanted in 3.3 +/- 1.3 lesions per patient. At 30 days, the cumulative MACE rate was 10.3%: 7.1% patients developed a non-Q-wave MI, 1.9% developed a Q-wave MI, 0.6% died for non-cardiac reasons, and 0.6% had a repeat revascularization. Clinical follow-up was obtained in all 112 eligible patients treated for 359 lesions at a mean time of 6.5 +/- 2.2 months. The cumulative MACE rate was 22.3%: 3 (2.7%) deaths (1 for cardiac reasons), 4 (3.6%) MIs, target lesion revascularization (TLR) in 16 (14.3%) patients with 24 (6.7%) lesions. Target vessel revascularization was required in 18 (16.1%) patients due to TLR of lesions treated with SES or to disease progression (1.8% of patients). Cox regression analysis revealed total stent length per patient as the most powerful independent predictor of MACE. Overall stent thrombosis occurred in three (1.9%) patients. CONCLUSIONS: Multivessel SES implantation can be safely performed on patients with complex coronary artery disease. The need for revascularization increases because of the cumulative effect of TLR on patients with multiple lesions.

Abstract: CONTEXT: Recent studies suggest that factors other than the degree of carotid stenosis are involved in ischemic stroke pathogenesis, especially modifications of plaque composition and related complications. OBJECTIVE: To examine the role of carotid plaque rupture and thrombosis in ischemic stroke pathogenesis in patients undergoing carotid endarterectomy, excluding those with possible cardiac embolization or with severe stenosis of the circle of Willis. DESIGN, SETTING, AND PATIENTS: A total of 269 carotid plaques selected from an Interinstitutional Carotid Tissue Bank were studied by histology after surgical endarterectomy between January 1995 and December 2002. A total of 96 plaques were from patients with ipsilateral major stroke, 91 plaques from patients with transient ischemic attack (TIA), and 82 plaques from patients without symptoms. MAIN OUTCOME MEASURES: Differences in the frequency of thrombosis, cap rupture, cap erosion, inflammatory infiltrate, and major cardiovascular risk factors between study groups. RESULTS: A thrombotically active carotid plaque associated with high inflammatory infiltrate was observed in 71 (74.0%) of 96 patients with ipsilateral major stroke (and in all 32 plaques from patients operated within 2 months of symptom onset) compared with 32 (35.2%) of 91 patients with TIA (P < .001) or 12 (14.6%) of 82 patients who were without symptoms (P < .001). In addition, a fresh thrombus was observed in 53.8% of patients with stroke operated 13 to 24 months after the cerebrovascular event. An acute thrombus was associated with cap rupture in 64 (90.1%) of 71 thrombosed plaques from patients with stroke and with cap erosion in the remaining 7 cases (9.9%). Ruptured plaques of patients affected by stroke were characterized by the presence of a more severe inflammatory infiltrate, constituted by monocytes, macrophages, and T lymphocyte cells compared with that observed in the TIA and asymptomatic groups (P = .001). There was no significant difference between groups in major cardiovascular risk factors. CONCLUSION: These results demonstrate a major role of carotid thrombosis and inflammation in ischemic stroke in patients affected by carotid atherosclerotic disease.

Abstract: The impact of the use of sirolimus-eluting stents (SESs) in the treatment of in-stent restenosis in previously irradiated sites has not been adequately evaluated. Fifteen consecutive patients who underwent percutaneous coronary interventions using SESs in lesion sites previously intervened with intracoronary radiation therapy were identified. All stents were implanted successfully, and there were no major in-hospital complications. At 30-day follow-up, there was 1 case of subacute thrombosis that led to target lesion revascularization (TLR). At 6 months, 2 patients underwent TLR because of recurrent angina with angiographic restenosis, and 1 patient underwent target vessel revascularization distally to the SES site; no other major adverse cardiac events occurred at long-term follow-up (mean 17 +/- 8 months).

Abstract: OBJECTIVES: This observational study evaluated the clinical and angiographic outcomes of patients with aorto-ostial coronary artery disease treated with sirolimus-eluting stents (SESs) or with bare metal stents (BMSs). BACKGROUND: The safety and effectiveness of SESs for the treatment of aorto-ostial lesions have not been demonstrated. METHODS: We identified 82 consecutive patients who underwent percutaneous coronary interventions in 82 aorto-ostial lesions using the SES (32 patients) or BMS (50 patients) and compared the two groups of patients. The incidence of major adverse cardiac events (MACE), including death or Q-wave myocardial infarction (MI), target lesion revascularization (TLR), and target vessel revascularization (TVR), were recorded in-hospital and at a 10-month follow-up. RESULTS: All stents were implanted successfully. There were no statistically significant differences regarding major in-hospital complications between the two groups. At 10-month follow-up, two (6.3%) patients in the SES group and 14 (28%) patients in the BMS group underwent TLR (p = 0.01); MACE were less frequent in the SES group compared to the BMS group (19% vs. 44%, p = 0.02). Angiographic follow-up showed lower binary restenosis rates (11% vs. 51%, p = 0.001) and smaller late loss (0.21 +/- 0.31 mm vs. 2.06 +/- 1.37 mm, p < 0.0001) in the SES group. CONCLUSIONS: The main finding of our study is that, compared to the BMS, implantation of the SES in aorto-ostial lesions appears safe and effective, with no increase in major in-hospital complications and a significant improvement in restenosis and late event rates at 10-month follow-up.

Abstract: OBJECTIVE: Drug eluting stents have been shown to reduce the rate of in-stent restenosis in cases where single lesions are treated. The performance of these stents, in patients with multivessel disease and complex lesions, however, remains unknown. Our experience with sirolimus eluting stents in such patients is presented. DESIGN AND PATIENTS: This study includes all consecutive patients treated at San Raffaele Hospital and EMO Centro Cuore Columbus, Milan, Italy treated with sirolimus eluting stents. RESULTS: Between April 2002 and March 2003, 486 patients with 1027 lesions were treated (437 males, 49 females) with a mean (SD) age of 62.2 (10.5) years. Of all patients studied, 19.1% had single vessel disease, 33.8% had two vessel disease, and 47.1% had three vessel disease. Of the whole study group, 20.3% of patients had diabetes mellitus. A mean (SD) of 2.3 (0.4) stents per patient and 1.1 (0.2) stents per lesion were implanted. The baseline mean reference diameter was 2.7 (0.6) mm with a mean minimal luminal diameter of 0.9 (0.5) mm. Post-stenting, the acute gain was 1.8 (0.6) mm. During hospital stay one patient died (0.2%) and 13 (2.7%) patients had in-hospital myocardial infarction (MI). One patient required urgent repeat percutaneous coronary intervention. Six months clinical follow up was performed in all 347 eligible patients. Six months mortality was 2.0% (n = 7) and acute MI occurred in 0.3% (n = 1). Target lesion revascularisation occurred in 9.5% (n = 33) of the patients and target vessel revascularisation (TVR) in 11.5% (n = 40) of the patients. Major adverse cardiac event rate was 13.8% (n = 48). TVR was 4.5% for single vessel disease and 13.2% for multivessel disease. Diabetes mellitus was the only significant predictor for TVR. CONCLUSION: The use of drug eluting stents in single and multivessel coronary disease produces good short and medium term results with a low rate of revascularisation. Longer term follow-up is required to confirm these observations.

Abstract: Stroke is the second most common cause of death in developed countries. Carotid plaque disruption and distal embolization of atheromatous debris are the most common pathogenic mechanisms for cerebral ischemia from carotid atherosclerotic disease. Morphologic composition of the atherosclerotic plaque, rather than the stenotic severity, appears to be central in determining the risk of both plaque rupture and subsequent thrombosis. Histologic features of vulnerable plaques include a large lipid core, a thin fibrous cap, intraplaque hemorrhage, and an increased number of inflammatory cells, mostly monocyte-macrophages. Due to the catastrophic implications of thrombus formation and embolization on the arterial plaque, detection before major neurologic events occur is now a major goal of cardiovascular clinicians and researchers. New detection imaging techniques such as intravascular thermography, optical coherence tomography, photonic spectroscopy, and elastography have been developed in order to document atherosclerotic lesion composition. This review will focus on the new possibilities under investigation for vulnerable atherosclerotic carotid plaque detection by means of the serologic markers of plaque instability. New markers, such as pregnancy-associated protein A, P-selectin, interleukin-6 and interleukin-12, metalloproteinases, lipoprotein(a), and oxidation products have been reviewed. Most of the promising serologic markers in this article are still in a nascent phase of development and remain to be validated in clinical settings. However, these biohumoral markers, and their potential combination of techniques, may hold promise for the future characterization of the vulnerable plaque and moreover of the vulnerable patient.

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Abstract: OBJECTIVES: We sought to test the hypothesis of whether inflammatory cell infiltration in patients dying of an acute myocardial infarction (MI) is a multifocal event involving multiple coronary branches. BACKGROUND: Coronary instability is thought to reflect local disruption of a single vulnerable plaque. However, previous postmortem studies have not addressed the question of whether activation of inflammatory cells, particularly T lymphocytes, is limited to the culprit lesion only or rather diffuse in the coronary circulation. METHODS: We performed a systematic flow cytometric study in three groups of autopsied patients (group 1 = acute MI; group 2 = old MI; group 3 = no ischemic heart disease). Cell suspensions of enzymatically digested coronary arteries were stained for flow cytometry with CD3, CD68, alpha-smooth muscle actin, and human leukocyte antigen (HLA)-DR antibodies. RESULTS: The coronary plaques showed: 1) a higher proportion of inflammatory cells in groups 1 and 2 than in group 3; 2) a higher percentage of T lymphocytes in group 1 than in group 2 (11.67 +/- 0.70% vs. 5.67 +/- 0.74%, p = 0.001) and in group 2 than in group 3 (p = 0.008); and 3) diffuse cell activation in the whole coronary tree of group 1, but not of group 2 subjects. CONCLUSIONS: Our study suggests that lymphocytes may play a key role in coronary instability by determining activation of various cellular types throughout the coronary circulation. Activated T lymphocytes and their products may well represent a new target in both the treatment and prevention of acute coronary syndromes.

Abstract: This report describes a case of a 47-year-old man who presented with early post-Q wave myocardial infarction angina and an atherosclerotic left anterior descending stenosis associated to a coronary-to-pulmonary artery fistula. Both coronary stenosis and fistula were successfully treated with a single polytetrafluoroethylene-covered stent graft implantation by intravascular ultrasound-guided procedure.

Abstract: BACKGROUND AND AIM OF THE STUDY: Aortic valve disease is presently the number one indication for valve replacement in the United States, yet its molecular mechanisms remain unknown. As apoptosis (programmed cell death) occurs in degenerative disease states, it was postulated that experimental hypercholesterolemia is associated with apoptosis in rabbit aortic valves. METHODS: New Zealand White rabbits (n = 8) were fed a 1% cholesterol diet for 12 weeks; control rabbits (n = 8) were fed a normal diet. After sacrifice of the animals, the aortic valves were dissected. Apoptosis was identified in the valvular lesion by TdT-mediated dUTP-biotin nick end-labeling (TUNEL) technique, and confirmed with transmission electron microscopy. The number of apoptotic cells was measured by computed morphometry. RESULTS: Valves from hypercholesterolemic rabbits showed an increase in apoptosis. TUNEL staining was identified in the atherosclerotic layer of hypercholesterolemic valves (0.1% of cells), but not in the cells of controls (p <0.0001). CONCLUSION: Apoptosis is increased in rabbit aortic valves during experimental hypercholesterolemia. If fatal cellular degeneration occurs in hypercholesterolemic valve disease, these data suggest that apoptosis may play a role in the mechanism of valvular disease.

Abstract: AIM: sudden coronary death (SCD) in older individuals is generally associated with extensive coronary atherosclerosis, although it may be the first manifestation of ischaemic heart disease. In younger age-groups, SCD may occur in the presence of less severe disease. We sought to (1) examine the extent of coronary atherosclerosis in young victims of SCD compared with age- and sex-matched controls, (2) analyse the composition of atherosclerotic plaques in these patients, (3) identify the predominant mechanism of SCD, and (4) evaluate the possibility of detecting this mechanism on the basis of morphologic plaque features, in particular presence and amount of lipid accumulation and calcific deposits. METHODS AND RESULTS: coronary arteries were obtained at autopsy from 28 victims of SCD under age 50 with no prior clinical manifestation of ischaemic heart disease (IHD) and no myocardial scar formation and from 16 age- and sex-matched subjects dying of noncardiac causes out of hospital. Sections of all available major coronary arteries were cut in 5-mm intervals to yield a total of 1357 histologic sections, which were analysed using digitised planimetry. Victims of SCD had significantly more major coronary arteries per subject with luminal area narrowing > or = 75% than controls (on average, 2.1 vs. 0.2). Plaque area per histologic section was 5.1 +/- 2.1 mm(2) in SCD cases and 2.0 +/- 0.9 mm(2) in controls (P < 0.001). The major constituent of all plaques was fibrous tissue. Lipid core area per section was 0.49 +/- 0.59 mm(2) in SCD cases and 0.004 +/- 0.01 mm(2) in controls (P < 0.001), and calcified plaque area was 0.18 +/- 0.19 mm(2) in SCD cases and 0.02 +/- 0.05 mm(2) in controls (P < 0.001), both defining significant differences between SCD cases and controls. Arterial thrombosis, most often with underlying plaque rupture was the mechanism of SCD in > 80% of the cases. Considering histologic sections with > or = 50 and with > or = 75% area stenosis, plaque rupture was independently predicted by lipid core area. Calcific deposits were a frequent feature of plaque rupture but were only associated with it in univariate analysis. CONCLUSIONS: the extent and severity of coronary atherosclerosis in young victims of SCD as the first manifestation of IHD was substantially greater than in age-and sex-matched controls and comparable with that previously reported in SCD cases with a broader age range. Lipid core and calcified plaque areas provided for excellent separation between the two groups, which may have implications for identifying persons at increased risk for SCD by non invasive visualisation and assessment of the coronary arteries.

Abstract: BACKGROUND AND AIM OF THE STUDY: Limited data are available regarding the efficacy of mitral valve repair in patients affected by active, acute infective endocarditis. In addition, the predictivity of transesophageal echocardiography (TEE) for guiding the surgical decision-making process in these patients has not yet been reported. The study aim was to evaluate the long-term results of mitral valve repair and role of TEE in active, acute infective endocarditis. METHODS: The study population consisted of patients affected by infective endocarditis of the mitral valve who underwent surgery. TEE was performed intraoperatively to guide the best surgical approach. All patients were followed up (mean 73+/-8 months) after surgery. RESULTS: Twenty-eight patients underwent surgery for infective endocarditis; of these, 13 had mitral valve repair for active, acute infective endocarditis and formed the basis of the study. Sensitivity, specificity, positive predictive value, negative predictive value of TEE in detecting the mechanism of mitral regurgitation were 87%, 100%, 100% and 92%, respectively. The predictivity test of TEE in guiding surgical strategy was 94%. All patients were alive at the time of follow up; 10 (77%) were in NYHA class I and three in class II (23%). Mitral regurgitation was severe in one patient (8%), moderate in three (23%), mild in four (31%), and absent in five (38%). No relapses of active infective endocarditis were observed during the follow up period. CONCLUSION: Mitral valve repair appears to be an effective treatment for active, acute infective endocarditis with mitral regurgitation and should be considered as a therapeutic strategy when surgery is contemplated. TEE has a fundamental role in the surgical decision-making process in these patients.

Abstract: BACKGROUND: Structural alterations of aortic wall resulting from degradation of matrix proteins by matrix metalloproteinases (MMPs) characterize abdominal aortic aneurysms (AAAs). No studies have compared circulating levels of MMPs after endovascular graft (EVG) exclusion in comparison with open surgical repair (OSR) in patients affected by AAA. METHODS AND RESULTS: An abdominal angiography and CT scan were performed in all patients at the time of enrollment. A spiral CT scan was performed at 6 months to detect presence of endoleaks. MMP-3 and MMP-9 levels were measured before EVG (n=30) and OSR (n=15) treatments and at 1, 3, and 6 months of follow-up by a sandwich ELISA technique. Healthy volunteers (n=10) were used as control subjects. Immunohistochemical staining for MMP-9 and MMP-3 was performed on tissue samples from surgical cases. Both MMP-9 and MMP-3 mean basal levels were significantly higher in patients affected by AAA than in control subjects (32.3+/-20.7 ng/mL for EVG and 28+/-9.9 ng/mL for OSR versus 8.9+/-2.5 ng/mL, 2P<0.05; 18.3+/-9.7 ng/mL and 26.7+/-10.8 ng/mL versus 8.2+/-5.3 ng/mL, 2P<0.001). In the OSR group, both MMP-9 and MMP-3 mean levels decreased after surgery (28+/-9.9 ng/mL at basal versus 14.7+/-6.6 ng/mL at 6 months, 2P<0.001; 26.7+/-10.8 versus 12+/-5.3 ng/mL; 2P<0.001). In the EVG group, a statistically significant difference at 6-month follow-up in MMP-9 and MMP-3 mean plasma values was detected in patients who had endoleakage in comparison with patients without endoleakage (44.3+/-20.7 versus 14.6+/-7.0 ng/mL, 2P<0.005; 25+/-11.5 versus 10.3+/-5.4 ng/mL, 2P<0.005). CONCLUSIONS: After EVG exclusion, MMP-9 and MMP-3 levels decreased to a level similar to that of patients undergoing OSR. In addition, a lack of decrease in MMP levels after EVG exclusion may help in identifying patients who will have endoleakage and consequent aneurysm expansion caused by continuous sac pressurization during follow-up.

Abstract: PURPOSE: To test the vascular wall response to an expanded polytetrafluoroethylene-covered stent, compared with conventional stenting, up to 6 months after deployment in the vascular district of a swine model. METHODS: Fourteen minipigs underwent implantation of expanded polytetrafluoroethylene-covered stents (CS) and bare stents (BS) in five peripheral arteries. Animals were killed at different time points (from 1 to 180 days). Histopathologic assessment by morphologic and morphometric analysis and by scanning electron microscopy (SEM) were used to assess the incorporation characteristics and re-endothelialization extent of the two types of stents. RESULTS: A total of 70 stents (14 CS and 14 BS in the renal arteries; 28 CS in the iliac arteries, and 14 CS in the aorta) were implanted. Microscopic examination confirmed the absence of occlusive thrombi in both the CS and BS groups. Microthrombi were observed in 10 of 13 CS (77% of cases) and in four of four BS (100% of cases, p < 0.05). Inflammation was mild in 69% of segments in which a CS was implanted and in 74% of segments in which a BS was implanted (p = NS), while a severe inflammatory reaction was observed in 6% of CS segments and in 8% of BS segments (p = NS). No differences were detected at the long-term analysis between neointimal thickness in CS compared with BS segments (0.46 +/- 0.18 mm vs 0.42 +/- 0.26 mm at 90 days and 0.36 +/- 0.08 mm vs 0.35 +/- 0.04 mm at 180 days; p = NS, respectively). At SEM analysis, re-endothelization was evident 15 days after the implant in both CS and BS starting from the stent edges. CONCLUSION: CS implantation did not elicit a more severe thrombotic deposition compared with that of BS. A similar inflammatory reaction of the arterial wall was present in the two stent groups 3 and 6 months following the implant. In addition, CS implantation did not stimulate excessive neointimal formation when compared with BS.

Abstract: Coronary fistulas are uncommon anomalies of congenital and rarely iatrogenic etiology. Their clinical significance is mainly dependent on the severity of the left-to-right shunt they are responsible for. Symptoms, high-flow shunting and the occurrence of complications, only partially related to the magnitude of the shunt, are the main indications for their closure, especially in the adult population. Pediatric patients, even asymptomatic but presenting with electrocardiographic or chest X-ray abnormalities, should be treated in order to avoid the long-term complications related to the presence of the fistula. Treatment of adult asymptomatic patients with non-significant shunting is still a matter of debate. Surgery and direct epicardial or endocardial ligation were traditionally viewed as the main therapeutic method for the closure of coronary fistulas. Progress in the techniques of endoluminal intervention has led to fistula embolization using different devices including coils, balloons and chemicals. The success rate is good and the procedure-related morbidity acceptable.

Abstract: BACKGROUND: Insulin-like growth factors (IGF) I and II improve myocardial function after coronary occlusion in different animal models. OBJECTIVES: To investigate the mechanism of improved myocardial function after administration of IGF-I or IGF-II in acute myocardial infarction. METHODS: Female pigs (mean (SD) weight 25 (5) kg) were subjected to acute myocardial infarction by microembolisation with 75-150 micrometer affigel blue beads. The beads contained and slowly released 150 microgram/pig of IGF-I (n = 6), IGF-II (n = 6), or pig albumin (n = 6). Echocardiography, perfusion imaging, and haemodynamic measurements were performed before infarction and during four weeks after infarction. Regional wall motion of different left ventricular segments was scored semiquantitatively on the basis of a three point scoring system, from normal = 0 to dyskinesia = 3. Serum cardiac troponin I concentration was measured before, immediately after, and three hours after the infarct. Excised hearts were analysed for actin, desmin, blood vessel density, and DNA laddering within the infarct, border, and normal myocardial areas. RESULTS: Myocardial function of the infarct related area improved significantly during the four weeks of follow up in both the IGF groups (p = 0.01). Myocardial perfusion, heart rate, and blood pressure were similar in all the animals during the study. Treated animals had lower serum cardiac troponin I concentration (p = 0.001), more actin in the border area (p = 0.01) and infarct area (p = 0.0001), and reduced DNA laddering in the infarct area compared with the controls (p < 0.05). IGF groups had more blood vessels in the border area (p = 0.04) and the infarct area (p = 0.003). CONCLUSIONS: Both types of IGF improved myocardial function and the improvement was associated with preservation of myocardial structure. IGF-I was more effective than IGF-II.

Abstract: BACKGROUND: Epidemiological studies have demonstrated that hyperfibrinogenemia is an independent risk factor for cerebrovascular atherosclerosis. However, the underlying mechanisms are poorly understood. We studied whether hyperfibrinogenemia could modify the histological composition of atherosclerotic plaque and precipitate carotid thrombosis resulting from rupture of the plaque. METHODS AND RESULTS: We studied the histological composition of 71 carotid atherosclerotic plaques from patients who had undergone surgical endarterectomy after a first episode of transient ischemic attack. Patients were divided into 3 groups corresponding to the tertiles of plasma fibrinogen values. Hypercholesterolemia, hypertriglyceridemia, hypertension, diabetes, and smoking habit were also assessed. At the histological analysis, plaques of patients in the highest tertile of fibrinogen (>407 mg/dL) were characterized by a high incidence of thrombosis (66.7% of cases) compared with plaques of subjects in the lower (21.7%) (P=0.002) and middle (29. 2%) (P=0.009) tertiles. Plaque rupture was significantly associated with high fibrinogen levels (54.2%, P=0.003). Multivariate logistic regression indicated that hyperfibrinogenemia was an independent risk factor for a decrease in cap thickness (P=0.0005), macrophage foam cell infiltration of the cap (P=0.003), and thrombosis (P=0. 003). When the presence of other risk factors was accounted for, hyperfibrinogenemia remained an independent predictor of carotid thrombosis with an odds ratio of 5.83, compared with other risk factors. CONCLUSIONS: The results of the present study add to the evidence that hyperfibrinogenemia, independently of other risk factors, is associated with a specific histological composition of carotid atherosclerotic plaques that predisposes them to rupture and thrombosis.

Abstract: BACKGROUND: Despite the increasing use of stents, few reports have described human coronary artery morphology early and late after stenting. METHODS AND RESULTS: Histology was performed on 55 stents in 35 coronary vessels (32 native arteries and 3 vein grafts) from 32 patients. The mean duration of stent placement was 39+/-82 days. Fibrin, platelets, and neutrophils were associated with stent struts </=11 days after deployment. In stents implanted for </=3 days, only 3% of struts in contact with fibrous plaque had >20 associated inflammatory cells compared with 44% of struts embedded in a lipid core and 36% of struts in contact with damaged media (P<0.001). Neointimal growth determined late histological success, and increased neointimal growth correlated with increased stent size relative to the proximal reference lumen area. Neointimal thickness was greater for struts associated with medial damage than struts in contact with plaque (P<0.0001) or intact media (P<0.0001). When matched for time since treatment, neointimal cell density in stented arteries was similar to that in unstented arteries that had undergone balloon angioplasty and showed similar proteoglycan deposition. CONCLUSIONS: Morphology after coronary stenting demonstrates early thrombus formation and acute inflammation followed by neointimal growth. Medial injury and lipid core penetration by struts result in increased inflammation. Neointima increases as the ratio of stent area to reference lumen area increases. Deployment strategies that reduce medial damage and avoid stent oversizing may lower the frequency of in-stent restenosis.

Abstract: The altered coronary vasoactivity detected in experimental hypercholesterolemia before lesion formation is presumably due to an imbalance between vasodilating and vasoconstricting factors. Apoptosis, which has been previously described in advanced atherosclerosis, is modulated by vascular derived peptides with vasoactive properties. We hypothesized that coronary apoptosis occurs in experimental hypercholesterolemia prior to lesion formation. Pigs were sacrificed after being on either a high-cholesterol diet for 10-16 weeks (n = 17) or a normal diet (n = 9). Identification of apoptosis in each layer of coronary arteries and arterioles was performed by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL). In additional animals, ligation-mediated polymerase chain reaction (PCR) and transmission electron and confocal microscopy were done. Plasma cholesterol levels were higher in the cholesterol-fed animals (86+/-9 mg/dl versus 342+/-20 mg/dl, P < 0.001). Atheromatous plaques were not evident in the high-cholesterol group. TUNEL was positive in 11 of 17 hypercholesterolemic animals, primarily in the intima (1-2% of cells) and adventitia (3% of cells), but not in control vessels. A similar distribution was detected in arterioles. DNA bands were detected only in experimental animals, as were morphological features of apoptosis by transmission electron and confocal microscopy. In experimental hypercholesterolemia, apoptosis occurred in coronary arteries and arterioles before lesion formation. Apoptosis may be an integral process of early coronary atherosclerosis.

Abstract: Apoptosis is an active form of cell death that is intricately regulated and distinct from necrosis. Data suggest that apoptosis may play a role in the pathophysiology of coronary atherosclerotic disease. Anatomic evidence of apoptosis has been observed in coronary atherosclerosis, restenosis, and transplant arteriopathy, accompanied by an increase in biochemical and genetic markers of apoptosis. Vasoactive substances such as nitric oxide and angiotensin II also regulate vascular smooth muscle cell apoptosis; vasodilating factors may induce apoptosis, whereas vasoconstricting factors may inhibit apoptosis. The aim of this article is to review key points regarding the detection of apoptosis, its regulation, and its possible role in the pathogenesis of coronary artery disease.

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Abstract: Echocardiographic screening of asymptomatic relatives of patients with idiopathic dilated cardiomyopathy identifies a subset with left ventricular enlargement who are assumed to have early familial idiopathic dilated cardiomyopathy. This study shows for the first time that the myocardium in such relatives demonstrates abnormal cellularity.

Abstract: BACKGROUND: We studied the histomorphometric correlates of long-term successful coronary balloon angioplasty (percutaneous transluminal coronary angioplasty [PTCA]). Restenosis after PTCA may occur secondary to the failure of compensatory arterial enlargement or post-PTCA arterial constriction. The histopathology of this process in human subjects remains poorly defined. METHODS: Forty-two coronary segments from 41 patients treated with PTCA 60 +/- 58 weeks before death were studied. The histomorphometric findings at the PTCA site were compared with those obtained at a proximal reference site. RESULTS: Histologic long-term success was seen in 18 (43%) of 42 arteries. Histologically successful PTCA arteries (PTCA site lumen of >/=50% of the reference lumen) demonstrated a larger acute lumen, smaller plaque size (normalized to the internal elastic lamina area), and thinner adventitia compared with histologic failures. Relative to the reference sites, histologically successful PTCA showed expansion of the external elastic lamina. In contrast, histologic failures showed a reduced external elastic lamina area, suggesting constrictive remodeling. Neointimal area correlated with the extent of internal elastic lamina disruption, but neither variable was related to histologic PTCA success or failure. CONCLUSIONS: These data provide histomorphometric confirmation of the hypothesis that constrictive remodeling, not neointimal formation, determines the long-term outcome of PTCA.

Abstract: OBJECTIVES: This study was designed to test the efficacy and safety of a fibrin-film-covered stent compared with that of a bare metal stent in the porcine coronary injury model. BACKGROUND: Biodegradable stents are a potential method of achieving total lesion coverage and delivering local, lesion-specific drug therapy. METHODS: Two coronary arteries in each pig were randomly assigned to deployment of either a fibrin-film or a bare tantalum wire-coil stent. An oversized balloon injury, 1.15 to 1.30 times the reference vessel diameter, was induced in each coronary segment before stenting to simulate angioplasty injury. Thirty pigs were studied: group 1 for 28 days (15 pigs); group 2 for 90 days (5 pigs); group 3 for 6 months (5 pigs); group 4 for 1 year (5 pigs). RESULTS: Two pigs died of occlusion of the bare stent and one of occlusion of the fibrin stent (p > 0.99). There were no significant differences between the fibrin-stented and bare-stented coronary segments with regard to arterial injury. In group 1 (28 days, 14 pigs), the mean neointimal thicknesses in the fibrin-stented and bare-stented groups were 0.57+/-0.31 and 0.57+/-0.27 mm, respectively (p=0.89). In groups 2 to 4 (90 days, four pigs; 6 months, four pigs; 1 year, five pigs), the mean neointimal thicknesses for fibrin- and bare-stented coronary segments at the times studied were 0.48+/-0.26 versus 0.50+/-0.22 mm at 90 days; 035+/-0.04 versus 0.35+/-0.16 mm at 6 months; and 0.33+/-0.14 versus 0.30+/-0.14 mm at 1 year (p=0.98). CONCLUSIONS: Fibrin-film stents appear to be an excellent candidate for local drug delivery because they can completely and safely cover the stented coronary segment while degrading slowly over 1 to 3 months. This result is important when compared with the poor results of previous studies of synthetic polymer stents.

Abstract: OBJECTIVES: This study was designed to evaluate whether calcium deposition in the coronary arteries is related to atherosclerotic plaque burden and narrowing of the arterial lumen. BACKGROUND: Many studies have recently documented the feasibility of electron beam computed tomography to detect and quantify coronary artery calcification in patients. Although these studies suggest a general relation between calcification and severity of coronary artery disease, the value of coronary calcium in defining atherosclerotic plaque and coronary lumen narrowing is unclear. Previous pathologic comparisons have failed to detail such a relation in identical histologic sections. This finding may be due to atherosclerotic remodeling. METHODS: A total of 37 nondecalcified coronary arteries were processed, sectioned at 3-mm intervals (723 sections) and evaluated by computer planimetry and densitometry. RESULTS: A significant relation between calcium area and plaque area was found on a per-heart basis (n = 13, r = 0.87, p < 0.0001), per-artery basis (left anterior descending coronary artery [LAD]: n = 13, r = 0.89, p < 0.0001; left circumflex coronary artery [LCx]: n = 11, r = 0.7, p < 0.001; right coronary artery [RCA]: n = 13, r = 0.89, p < 0.0001) and per-segment basis (n = 723, r = 0.52, p < 0.0001). In contrast, a poor relation existed between residual histologic lumen area and calcium area for individual hearts (r = 0.48, p = NS), individual coronary arteries (LAD: r = 0.59, p = NS; LCx: r = 0.10, p = NS; RCA: r = 0.59, p = NS) and coronary segments (r = 0.07, p = NS). Longitudinal changes in external elastic lamina areas were highly correlated with changes in plaque area values (r = 0.60, p < 0.0001), whereas lumen area did not correlate with plaque size change (r = 0.01, p = NS). CONCLUSIONS: Coronary calcium quantification is an excellent method of assessing atherosclerotic plaque presence at individual artery sites. Moreover, the amount of calcium correlates with the overall magnitude of atherosclerotic plaque burden. This study suggests that the remodeling phenomenon is the likely explanation for the lack of a good predictive value between lumen narrowing and quantification of mural calcification.

Abstract: The internal elastic lamina (IEL) serves as a barrier for cells and macromolecules migration between the intima and the media in the vascular wall. Several investigators have reported internal elastic lamina ultrastructural changes in elastic arteries with atherosclerosis. However, no quantitative and qualitative assessment of the internal elastic lamina architecture in muscular arteries such as the coronary circulation during early atherosclerosis have been performed yet. In this study, we therefore evaluated the ultrastructural morphological changes of the IEL in the coronary circulation of pigs fed with high cholesterol diet. Animals were sacrificed after being fed either a high cholesterol diet for 10-12 weeks (n = 5, 12 coronary segments) or a control diet (n = 4, 15 coronary segments). Coronary arteries were analyzed by transmission and scanning electron microscopy. In addition, computerized digital analysis of the images obtained by confocal scanning microscopy was performed for the quantitation of the morphologic changes in the internal elastic lamina. Confocal microscopy and scanning electron microscopy revealed an altered pattern characterized by large oval fenestration formation in the internal elastic lamina of hypercholesterolemic animals. Computerized morphometric analysis of confocal microscopy images demonstrated that compared to controls, the IEL of cholesterol-fed animals was characterized by an increase in the minor diameter of the fenestrae (2.16 +/- 0.04 microm versus 3.32 +/- 0.06 microm, P = 0.003) and a decrease in the fenestrae density (22333 +/- 1334/mm2 versus 17552 +/- 931/mm2, P = 0.015) of the internal elastic lamina. The percentage of the IEL area covered by the fenestrae correlated with the intimal thickness (r = 0.79, P = 0.004). This study demonstrates that experimental hypercholesterolemia is characterized by ultrastructural changes of the internal elastic lamina in the coronary circulation. This study suggests that the IEL may play an important role in the development of structural changes which characterize the early phase of coronary atherosclerosis.

Abstract: Coronary arteries contain a network of vasa vasorum in the adventitia. The three-dimensional anatomy of the vasa vasorum in early coronary atherosclerosis is unknown. This study was designed to visualize and quantitate the three-dimensional spatial pattern of vasa vasorum in normal and experimental hypercholesterolemic porcine coronary arteries, using a novel computed tomography technique. Animals were killed after being fed either a high cholesterol diet (n = 4) or a control diet (n = 4) for 12 wk. The proximal left anterior descending coronary artery was removed from the heart, scanned, and reconstructed, and quantitation of vasa vasorum density was performed. Two different types of vasa vasorum were defined: first-order vasa vasorum ran longitudinally parallel to the vessel and second-order originated from first-order vasa circumferentially around the vessel wall. Compared with controls in hypercholesterolemic coronary arteries, there was a significant increase in the area of the vessel wall (3.86+/-0.22 vs. 8.07+/-0.45 mm2, respectively, P < 0.01) and in the density of vasa vasorum (1. 84+/-0.05/mm2 vs. 4.73+/-0.24/mm2; respectively, P = 0.0001). This occurred especially by an increase of second-order vasa vasorum and disorientation of normal vasa vasorum spatial pattern. This study suggests that adventitial neovascularization of vasa vasorum occurs in experimental hypercholesterolemic coronary arteries and may be a part of the early atherosclerotic remodeling process.

Abstract: Controversy continues regarding the mechanism of coronary restenosis. While neointimal thickening was initially considered the major cause, recent studies suggest that changes in arterial size, or remodeling, plays an important or even dominant role in late lumen loss. Moreover, neointimal thickness and remodeling may be interrelated. The field has been complicated by the fact that remodeling analyses have not used consistent definitions or methods. In this editorial we thus describe a quantitative paradigm for remodeling analyses: as arterial plaque or neointima forms in an artery, it is accompanied by luminal encroachment, artery expansion or gradations of either. In this manner, remodeling is generally defined as any arterial size change (enlargement or contraction), independent or dependent of neointimal thickening. Standardization of definitions and quantitative methods may improve understanding of the components of restenosis resulting from artery size changes, neointimal thickening and their impact on lumen size.

Abstract: OBJECTIVES: The objective of this study was to examine the quantitative response of the adventitial vasa vasorum to balloon-induced coronary injury. BACKGROUND: Recent attention has focused on the role of vasa vasorum in atherosclerotic and restenotic coronary artery disease. However, the three-dimensional anatomy of these complex vessels is largely unknown, especially after angioplasty injury. The purpose of this study was to visualize and quantitate three-dimensional spatial patterns of vasa vasorum in normal and balloon injured porcine coronary arteries. We also studied the spatial growth of vasa vasorum in regions of neointimal formation. A novel imaging technique, microscopic computed tomography, was used for these studies. METHODS: Four pigs were killed 28 d after coronary balloon injury, and four pigs with uninjured coronary arteries served as normal controls. The coronary arteries were injected with a low-viscosity, radiopaque liquid polymer compound. Normal and injured coronary segments were scanned using a microscopic computed tomography technique. Three-dimensional reconstructed maximum intensity projection and voxel gradient shading images were displayed at different angles and voxel threshold values, using image analysis software. For quantitation, seven to 10 cross-sectional images (40 normal and 32 balloon injured cross-sections) were captured from each specimen at a voxel size of 21 microm. RESULTS: Normal vasa vasorum originated from the coronary artery lumen, principally at large branch points. Two different types of vasa were found and classified as first-order or second-order according to location and direction. In balloon-injured coronary arteries, adventitial vasa vasorum density was increased (3.16+/-0.17/mm2 vs. 1.90+/-0.06/mm2, p = 0.0001; respectively), suggesting neovascularization by 28 d after vessel injury. Also, in these injured arteries, the vasa spatial distribution was disrupted compared with normal vessels, with proportionally more second-order vasa vasorum. The diameters of first-order and second-order vasa were smaller in normal compared with balloon-treated coronary arteries (p = 0.012 first-order; p < 0.001, second-order; respectively). The density of newly formed vasa vasorum was proportional to vessel stenosis (r = 0.81, p = 0.0001). Although the total number of vasa was increased after injury, the total vascular area comprised of vasa was significantly reduced in injured vessels compared with normals (3.83+/-0.20% to 5.42+/-0.56%, p = 0.0185). CONCLUSIONS: Adventitial neovascularization occurs after balloon injury. The number of new vessels is proportional to vessel stenosis. These findings may hold substantial implications for the therapy of vascular disease and restenosis.

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Abstract: BACKGROUND: The extent and nature of unfavorable geometric remodeling, especially related to the adventitia, has not been studied previously. The purpose of this study was to examine two methods of experimental arterial injury, characterize the extent of remodeling, and determine if remodeling is injury-specific. METHODS: Two methods for producing coronary stenoses in pigs were used: heat injury using thermal balloon angioplasty (resulting in adventitial fibrosis), and copper stent implantation (resulting in intense inflammation). Histomorphometric parameters included changes in neointimal thickness (delta neointima) from uninjured to injured sections, and differences in area circumscribed by the internal and external elastic laminas (delta internal elastic lamina area and delta external elastic lamina area, respectively). Remodeling was calculated for each lesion as the enlargement of the external elastic lamina area or internal elastic lamina area for incremental neointimal thickening, expressed as the slopes delta external elastic area/delta neointima and delta internal elastic lamina area/delta neointima. RESULTS: Remodeling indices for the heat lesions for the heat lesions were negative (delta internal elastic lamina area/delta neointima = 0.15, delta external elastic lamina area/delta neointima = 0.64) and indicated little remodeling in contrast to copper stent injury (delta internal elastic lamina area/delta neointima = 0.95, delta external elastic lamina area/delta neointima = 1.20). CONCLUSIONS: Remodeling in fibrotic compared to inflammatory lesions differs markedly, and may explain increased restenosis rates observed in thermal balloon angioplasty in patients. This formulation may be useful to study remodeling and restenosis following interventional technologies.

Abstract: OBJECTIVES: Age-related changes in histologic composition and neovascular channel (NC) pattern of angiographic chronic total coronary artery occlusions (CTOs) were studied to define histologic correlates of age-related revascularization profiles and neovascular channel formation. BACKGROUND: Revascularization of CTOs is frequently characterized by inability to cross or dilate the lesion and a high incidence of reocclusion or restenosis but low periprocedural ischemic complication rates. Little is known about the histopathologic basis of these observations. METHODS: Ninety-six angiographic CTOs from autopsy studies in 61 patients who had undergone coronary angiography within 3 months of death were studied. Abrupt plaque rupture was excluded. Occlusion segments were analyzed for 1) histologic composition as a function of lesion age; and 2) NC pattern as a function of lesion age and intimal plaque (IP) composition. RESULTS: Cholesterol and foam cell-laden IP was more frequent in younger lesions (p = 0.0007), whereas fibrocalcific IP increased with CTO age (p = 0.008). IP NCs arose directly from adventitial vasa vasorum and were anatomically and quantitatively related in terms of number and size (p = 0.0001) to the extent of IP cellular inflammation. IP cellular inflammation exceeded that found in the adventitia (p < 0.001) or media (p = 0.0001) across all CTO ages. In CTOs < 1 year old, the adventitia was associated with a larger number and size of NCs relative to the IP (p = 0.0006 and p = 0.009), media (p = 0.0001 and p = 0.002) and recanalized lumen (p = 0.0001 and p = 0.001). In CTOs >1 year old, the adventitia and IP NC numbers were similar and exceeded NC numbers found in the media (p = 0.0001) and recanalized lumen (p = 0.0001 and p = 0.003). CONCLUSIONS: Angiographic CTO frequently corresponds to less than complete occlusion by histologic criteria. Age-related changes in IP composition from cholesterol laden to fibrocalcific may explain the adverse revascularization profile of older CTOs. IP NC growth derived from the adventitia increases with age and is strongly associated with IP cellular inflammation. IP NC formation may protect against the flow-limiting effects of IP growth.

Abstract: The incidence of cardiovascular diseases that are related to the atherosclerotic process increases exponentially with age. Organ lesions, the clinical manifestation of atherosclerotic disease, are late events due to complications in the plaque (ulceration, thrombosis, calcification) which are the result of an increased vulnerability to disruption of a previously stable plaque. The higher incidence of age-related clinical events could be explained by a rising sensitivity of plaques to destabilising factors, both parietal and humoral. The increased probability that a plaque in an elderly patient will became vulnerable could be related to those destabilising factors that significantly increase with aging, such as advanced glycation end-products. For these reasons, it seems most important that the analysis of these age-related destabilising factors, rather than those factors that promote the development of early atherosclerotic plaques, should be undertaken. Taking the point of view of a pharmacological intervention, this should eventually lead to a more complete understanding of this process.

Abstract: Acute stent thrombosis remains a major concern of coronary stent implantation. Animal studies using stents do not adequately mimic this clinical problem, since stent placement is rarely associated with acute closure. The purpose of this study was to develop and characterize a porcine model of stent thrombosis. Improved understanding through such a model may be useful toward preventing and treating acute stent closure. Whole blood was drawn from domestic crossbred swine one day before study. Platelets were isolated, labeled with 111-In tropolone, and reinjected within 18 hr of the study. Bilateral carotid arteries were exposed, and severe injury induced by a series of mechanical crushes. This method produced histologic injury similar to human coronary angioplasty, with medial disruption and large dissections protruding into the lumen. Stenting was performed in standard fashion with 3.5-mm JJIS stents. Local platelet deposition was measured and recorded as 111-In radioactivity using a miniaturized scintillation detector (Dosimeter Corp.) mounted directly at the artery injury site. This measurement was made in real time at 1-min intervals. Similarly, volumetric blood flow was measured in real time by Doppler flowmeter. Eighteen arteries of nine pigs were studied. In nine arteries from nine pigs, crush injury only was performed and monitored. In the contralateral artery, crush injury was followed immediately by placement of a 3.5-mm Palmaz-Schatz (coronary) stent. Blood flow decreased rapidly following injury in both groups and followed a cyclic pattern. Eight arteries of the crush alone and two arteries of the crush plus stent groups were totally occluded 1 hr after crush. 111-In counts normalized to baseline were significantly higher at 1 hr in both groups compared to baseline; in the stented group, counts were higher than in the unstented group. Blood flow was higher in the stented group than in unstented group for 1 hr. Histopathologic observation of the thrombi forming in both crush-only and crush-stent injuries showed severe medial dissections with obstructing medial flap formation. The thrombi forming in both groups were highly platelet rich. This model of stent and arterial thrombosis showed rapid formation of platelet-rich thrombus, cyclic blood flow variations, and acute occlusion in 20% of cases. Stent placement at arterial injury sites is associated with thrombus that is predominantly platelet rich. Stent placement at injury sites enhances platelet deposition over crush injury alone. Despite greater numbers of platelets, as shown by increased 111-In counts, stenting improved vessel patency. These were likely due to higher volumetric blood flow, continuous deposition, and embolization of labeled platelets.

Abstract: Experimental studies suggest that DNA content is increased in the smooth muscle cells of the arteries of hypertensive animals. It is unclear whether an increase in DNA content occurring in the smooth muscle cells of hypertensive rats represents a pressure-dependent effect. To evaluate the antihypertensive effect of long-term treatment with propionyl-L-carnitine and the possible morphological changes in thoracic smooth muscle cells correlated with this effect, we studied 4-month-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) randomly divided into five groups. One group of SHR was treated with propionyl-L-carnitine for 12 months; the other four groups of SHR and WKY received no treatment and were controls. We used static and flow cytometry to evaluate the polyploid cell content in thoracic aorta smooth muscle cells. Systolic pressure in untreated SHR progressively increased during the experiment. Treatment did not significantly influence pressure values in SHR. In WKY, blood pressure was significantly lower than that in treated and untreated age-matched SHR (2P < .02). The number of polyploid smooth muscle cells was significantly lower in the propionyl-L-carnitine-treated SHR than in the untreated rats (2P < .04) and similar to values for WKY. The reduction of polyploid cells in treated SHR was paralleled by a significant decrease of the aortic total DNA content, whereas no modifications occurred in smooth muscle cell mass. Long-term treatment with propionyl-L-carnitine may interfere with cellular mechanisms regulating the secondary responses involved in DNA synthesis.

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Abstract: We report a case of drug-induced Kaposi's sarcoma (KS) on the sole of the right foot in a 71-year-old man, treated for 6 months with corticosteroid therapy (prednisolone 25 mg/day) for pericardial effusion. After corticosteroid withdrawal, a tuberculin skin test became strongly positive and pericardial effusion was considered to be of tubercular origin. The patient remained constantly HIV negative during 14 months of follow-up. Seven months after continuous antitubercular treatment, the KS nodules regressed spontaneously and finally disappeared. Histological studies confirmed the diagnosis of KS and documented its complete regression. Laboratory investigation confirmed prior exposure to CMV, EBV and HSV and suggested drug-induced immunological suppression. Analysis of the HLA system revealed the positivity of locus DR5, associated with classical KS. This case report underscores the relationship between genetic background, environmental factors, drug-induced immunosuppression and the evolution of this peculiar neoplasm.