Jan D. Schmitto, MD, PhD Cardiothoracic Surgeon Division of Cardiac Surgery Brigham and Women´s Hospital Harvard Medical School 75 Francis Street Boston, MA 02115 USA jschmitto@gmx.de
After finishing medical school in Munster, Germany and Vienna, Austria, Dr. Schmitto completed his cardiothoracic-residency at University Hospital of Gottingen,Germany as one of the youngest cardiothoracic surgeons worldwide. Presently, he serves as a fellow in the Division of Cardiac Surgery, Brigham and Women´s Hospital, Harvard Medical School, Boston, USA. Cardiac research has always been an integral component of Dr. Schmitto’s academic career - leading to a high number of scientific publications, including many first author papers and two books. Additionally, he serves as a reviewer for several international professional cardiology and cardiothoracic surgery journals.
Abstract: Cooling before circulatory arrest or ischemic arrest has been reported to influence myocardial performance in isolated neonatal hearts. The aim of the present study was to analyze indices of myocardial contractility and relaxation in an in vivo neonatal model after deep hypothermic circulatory arrest (DHCA). DHCA (18°C; DHCA group; n = 8) or mild hypothermic cardiopulmonary bypass ([MH-CPB] 32°C; MH-CPB group; n = 10) was applied in newborn piglets. After reperfusion (60 and 120 min), left ventricular dP/dt(max) increased in DHCA and MH-CPB, while -dP/dt(max) decreased slightly in DHCA and increased in MH-CPB. Nevertheless, the differences between the two groups did not reach statistical significance. In conclusion, left ventricular contractility remained stable after reperfusion following DHCA, to some degree at the expense of the diastolic function.
Abstract: ABSTRACT: BACKGROUND: Increasing number of scientists are enthusiastic about using free, open source software for their research purposes. Authors' specific goal was to examine whether a Linux-based operating system with open source software packages would allow to prepare a submission-ready scientific manuscript without the need to use the proprietary software. FINDINGS: Preparation and editing of scientific manuscripts is possible using Linux and open source software. This letter to the editor describes key steps for preparation of a publication-ready scientific manuscript in a Linux-based operating system, as well as discusses the necessary software components. This manuscript was created using Linux and open source programs for Linux.
Abstract: The reported incidence of deep sternal wound infection (DSWI) after cardiac surgery is 0.4-5% with Staphylococcus aureus being the most common pathogen isolated from infected wound sternotomies and bacteraemic blood cultures. This infection is associated with a higher morbidity and mortality than other known aetiologies. Little is reported about the optimal antibiotic management. The aim of the study is to quantify the application of daptomycin treatment of DSWI due to gram-positive organisms post cardiac surgery. We performed an observational analysis in 23 cases of post sternotomy DSWI with gram-positive organisms February 2009 and September 2010. When the wound appeared viable and the microbiological cultures were negative, the technique of chest closure was individualised to the patient. The incidence of DSWI was 1.46%. The mean dose of daptomycin application was 4.4 ± 0.9 mg/kg/d and the average duration of the daptomycin application was 14.47 ± 7.33 days. In 89% of the patients VAC therapy was used. The duration from daptomycin application to sternal closure was 18 ± 13.9 days. The parameters of infection including, fibrinogen (p = 0.03), white blood cell count (p = 0.001) and C-reactive protein (p = 0.0001) were significantly reduced after daptomycin application. We had no mortality and wound healing was successfully achieved in all patients. Treatment of DSWI due to gram-positive organisms with a daptomycin-containing antibiotic regimen is safe, effective and promotes immediate improvement of local wound conditions.Based on these observations, daptomycin may offer a new treatment option for expediting surgical management of DSWI after cardiac surgery.
Abstract: Renal failure after open heart surgery is a serious complication even in the pediatric population. The aim of the present study was to analyze morphological changes after cardiopulmonary bypass (CPB) surgery in a neonatal piglet model. The kidneys of newborn piglets sacrificed 6 h after CPB were examined (CPB; n = 4) regarding tubular dilatation, vacuole formation, leukocytic infiltration, epithelial destruction, and interstitial edema. Thereafter, the findings were compared with the morphology of normal (untreated) neonatal piglet kidneys (control; n = 4). All changes but the interstitial edema were statistically significant if compared with the normal renal tissue: tubular dilatation (CPB vs. control P < 0.05), vacuole formation (CPB vs. control P < 0.05), leukocytic infiltration (CPB vs. control P < 0.05), and epithelial destruction (CPB vs. control P < 0.001). In conclusion, CPB induces significant changes in the morphology of the neonatal piglet kidneys.
Abstract: The legal obligation of the European Working Time Directive with its implementation into a German Working Hours Act requires German hospitals to give up old structures and requires the implementation of new working time models. The failure of the revision of the European Working Time Directive in April 2009 prevented that any changes of status quo might happen in the near future. Fundamental terms of the working law for the medical area have been elucidated and have been implemented into concrete calculation formulas. The planned working time has been clearly determined. Particularly, on-call duties and a signed "OptOut-declaration" have huge effects on the upper limit of the working time that is to be determined. Shift duty leads to the greatest limitations of the upper limit of the working time. The Working Hours Act defines the maximal, available, individual working time budget and thus the working time budget of a hospital and it limits the maximal availability of the service providers of a hospital as well as defining the maximal personnel costs. Transparency in this area lays the foundation for an effective time management and the creation of new working time models in accordance with the European Working Time Directive as well as the Working Hours Act and the "TVÄ" (labour contract for doctors at municipal hospitals). It is possible, with the knowledge of the maximal working time budget and the thereof resulting personnel costs, to calculate the economical revenues better. The reallocation of the working time of doctors enables efficiency enhancement. It is necessary to demand a clear definition of the tasks of doctors with the consequential discharge of tasks that should not/do not belong to the responsibilities of a doctor. This would lead to a more attractive working environment for doctors at hospitals and thus to an improvement of the care of the patients. The implementation of the European Time Directive is not to be seen as unrealizable, as has been generally heard; instead, it enables the urgently necessary structural reform at German hospitals.
Abstract: A 53-year-old Caucasian male suffering from idiopathic dilated cardiomyopathy underwent cardiac transplantation. Fifty-seven days following transplant, he developed posttransplant lymphoproliferative disorder (PTLD), which was Epstein-Barr virus positive. The initial episode of PTLD was treated with a dose reduction in cyclosporine (CsA) and a 4-week course of rituximab. Subsequent biopsies showed resolution of PTLD. One year posttreatment, his evaluation revealed severe cardiac allograft vasculopathy (CAV). The patient was switched to sirolimus-based immunosuppression regimen with gradual up-titration of sirolimus in combination with complete withdrawal of previously administered Calcineurin-based immunosuppression approach. The switchover was carried out over a 6-week period. In the following 3 years, there was CAV regression as well as PTLD remission, without any significant episode of rejection. Despite frequent relapses with this form of PTLD, the patient remains in remission, 8 years posttransplantation. In summary, sirolimus has been demonstrated to attenuate the progression of CAV, and this case report illustrates that regression of CAV is possible. In addition to preventing rejection, mammalian target of rapamycin inhibitors directly suppress signaling pathways leading to PTLD and may be effective monotherapy for preventing rejection and suppressing PTLD.
Abstract: Atrial fibrillation (AF) is the most common supraventricular arrhythmia and a major cause of morbidity. Arrhythmogenic foci originating within the pulmonary veins (PVs) are an important cause of both paroxysmal and persistent AF. A variety of endovascular and surgical techniques have been used to electrically isolate the PV from the left atrium. Pulmonary venography for localization of the PV ostium can be difficult to perform during the ablation procedure. While the anatomy of the PV is patient-specific, non-invasive imaging techniques may provide useful diagnostic information prior to the intended intervention. In this context, multidetector computed tomography (MDCT) visualization of the left atrial and PV anatomy prior to left atrial ablation and PV isolation is becoming increasingly important. MDCT imaging provides pre-procedural information on the left atrial anatomy, including atrial size and venous attachments, and it may identify potential post-procedural complications, such as pulmonary vein stenosis or cardiac perforations. Here, we review the relevant literature and present the current "state-of-the-art" of left atrial anatomy, PV ostia as well as the clinical aspects of refractory AF, MDCT imaging protocols and procedural aspects of PV ablation.
Abstract: Minimally invasive techniques are increasingly important in aortic valve surgery. The aim of this publication is to review our experience and recent literature to assess and present the current 'state-of-the-art'-role of minimally invasive aortic valve operations for high-risk patients.
Abstract: The CryoMaze procedure is usually limited to endocardial ablation under cardio-pulmonary bypass. Epicardial ablation is considered inferior as endocardial islets of atrial tissue could theoretically remain viable, protected from cryoinjury by epicardial fat and endocardial circulating warm blood. Novel argon-powered cryoprobes with lower ablation temperatures have recently become available. It is unclear if these instruments can reliably induce transmural atrial fibrosis by epicardial cryoablation on the beating heart.
Abstract: We present a case of sternal steel strut dislodgement and migration in a patient undergoing Ravitch repair for pectus excavatum (PE) 37 years ago. Broken struts perforated the right ventricle and right ventricular outflow tract (RVOT) and additionally migrated into the left upper lobar bronchus.Dislodged sternal struts represent rare complications after surgical repair of patients suffering from pectus excavatum. Reviewing the literature, only five cases of intrapericardial migration of dislodged sternal struts or wires have been reported so far.In our case, the first strut was removed from the airways through a left antero-lateral thoracotomy. Using cardiopulmonary bypass, a second strut was removed via ventriculotomy. These life-threatening sequelae underscore the importance of postoperative follow-up and early removal of osteosynthetic materials used in open PE repair. Accurate preoperative localization of migrated materials and availability of CPB support are crucial for successful surgical removal. INTRODUCTION: The migration of dislodged sternal steel struts or wires into the pericardium and cardiac cavities is a rare but life-threatening complication of open pectus excavatum (PE) repair 1. Removal of these materials poses a challenge for cardiothoracic surgeons. Herein, the authors report a case of migration of dislodged steel struts through the right ventricle and right ventricular outflow tract (RVOT) into the left upper lobar bronchus in a patient who underwent Ravitch repair 37 years ago.
Abstract: AIM: Proton pump inhibitors (PPI), e.g. pantoprazole (PP), esomeprazole (EP) and omeprazole (OP), work as anti-ulcer/gastrointestinal reflux drugs. Also, they are widely used in postoperative care of patients in cardiac surgery to prevent upper gastrointestinal bleeding. Therefore, in western industrial countries they play a major economic role, representing one of the most important drugs in open heart cardiac surgery. METHODS: Intact muscle strips (n=32) were isolated from the right ventricle wall of failing human hearts. In four different groups (PP, EP, OP, control group, each n=8), force amplitudes were recorded at a frequency of 60 beats per minute (bpm) with increasing PPI concentrations (0 to 320 µm/mL). RESULTS: In isometrically contracting muscle strips, significant negative inotropic effects were observed in the presence of all three PPI-groups (PP, EP and OP) with doses of 2.5 µg/mL and higher compared to the control group (p < 0.05 each). With high doses (320 µm/mL), force amplitudes could be almost completely depressed. The half maximal inhibitory concentration (IC50) for EP was 35.7 (confidence interval: 17.3-73.6) vs. OP 29.3 (6.8-126.6) vs. PP 25.1 (14.6-43.1) µg/mL (n.s.). No significant differences were found between the different proton pump inhibitors (PP, EP, OP) throughout the range of all concentrations. Relaxation was impaired in all PPI subgroups with prolonged time to 90% relaxation (RT90%) and maximum relaxation velocity (‑df/dt) was reduced, too. These effects were partially reversible after wash-out of the drugs. CONCLUSION: We conclude that proton pump inhibitors show significant negative inotropic effects on isolated human failing myocardium. There is no apparent difference seen in the magnitude of the effects of each PPI-group. Further, in-vivo investigations are necessary to reveal the clinical evidence of PPI's negative inotropic effects, e.g. in cardio-surgical patients with heart failure.
Abstract: Lipid-apheresis (LA) is thought to improve microcirculation. However, limited data are available on the effects on peripheral microcirculation. We investigated upper limb microcirculation of 22 patients undergoing regular LA on a weekly basis before and after LA. Using standardized semiquantitative scales, we analyzed blood flow, vasomotor function, and erythrocyte aggregation by capillary microscopy. In addition, capillary blood flow in quiescence and under heat and cryo-stress was evaluated by photoplethysmographic and laser Doppler anemometry. Moreover, levels of vasoactive mediators adrenalin, noradrenalin, endothelin-1 (ET-1), atrial natriuretic peptide (ANP), asymmetrical dimethyl-arginine (ADMA), as well as total protein and fibrinogen were measured. We found a significant increase in blood flow, the number of perfused capillaries and an improvement of erythrocyte aggregation by capillary microscopy. Using laser Doppler anemometry, we were able to show that this increase was predominantly located in the superficial layer capillaries (Δ44.53 ± 135.81%, n.s.) and less so in deeper layer arterioles (Δ2.75 ± 24.84%, n.s.). Vascular response to heat and cryo stress was also improved after LA but failed to reach significance. LA significantly reduced levels of epinephrin (-33 ± 39.2%), ANP (-28.8 ± 20.2%), ADMA (-74.1 ± 23%), and fibrinogen (-45.4 ± 19.7%) when comparing before LA and after LA values. In summary, we found an improvement in the microcirculation of the upper limbs under LA, which may result from a decrease of vasoconstrictors, improvement of vasomotor function, and a decrease in blood viscosity or erythrocyte aggregation.
Abstract: Traumatic pericardial rupture is a rare presentation. Pericardial rupture itself is asymptomatic unless complicated by either hemorrhage or herniation of the heart through the defect. Following diagnosis surgical repair of the pericardium is indicated because cardiac herniation may result in vascular collapse and sudden death.
Abstract: Minimally invasive mitral valve surgery (mini-MVS) has evolved into a safe and efficient surgical option for many patients. The overall complication rate is reduced, patient satisfaction increased, and hospital costs are lower with this approach, while providing safe and durable surgery. The repair/replacement of mitral valves via a minimally invasive technique represents a significant recent paradigm shift in cardiac surgery. The rapid development and refinement of minimally invasive valve surgery has enabled the repair of complex valves and, most importantly, has yielded similar results to those provided by standard surgical approaches.
Abstract: PURPOSE OF REVIEW: To assess the current status of the prevalence and variability of internal mammary graft use in contemporary multivessel coronary artery bypass graft (CABG). RECENT FINDINGS: The internal mammary artery (IMA) is considered the gold-standard conduit in coronary artery bypass graft (CABG) surgery. There is universal agreement that the IMA graft is associated with significantly improved short-term and long-term survival in CABG and the use of the IMA is recognized as a key performance measure world wide. In the recently developed Society of Thoracic Surgeons (STS) composite measure for CABG, use of an IMA was found to be the only intra-operative performance measure associated with quality of care. Furthermore, several studies have shown that bilateral IMA (BIMA) use improves long-term outcome compared with single IMA use. An objective assessment of surgical quality is essential to improve surgical outcomes. SUMMARY: There is strong evidence that IMA graft use is associated with significantly improved short-term and long-term survival in CABG. In spite of this, the prevalence of IMA grafting is less than expected. Moreover, there is a large variability in IMA use by hospital. There are also disparities in IMA use by sex and race, which should be addressed in the interest of expanding the benefits of IMA grafting to the maximum possible number of patients. Although the frequency of IMA use in CABG procedures seems to increase each year, further actions are necessary at the individual clinician, institutional, and political levels to improve quality of care.
Abstract: RATIONALE: Heart failure (HF) is known to be associated with increased Ca(2+)/calmodulin-dependent protein kinase (CaMK)II expression and activity. There is still controversial discussion about the functional role of CaMKII in HF. Moreover, CaMKII inhibition has never been investigated in human myocardium. OBJECTIVE: We sought to investigate detailed CaMKIIδ expression in end-stage failing human hearts (dilated and ischemic cardiomyopathy) and the functional effects of CaMKII inhibition on contractility. METHODS AND RESULTS: Expression analysis revealed that CaMKIIδ, both cytosolic δ(C) and nuclear δ(B) splice variants, were significantly increased in both right and left ventricles from patients with dilated or ischemic cardiomyopathy versus nonfailing. Experiments with isometrically twitching trabeculae revealed significantly improved force frequency relationships in the presence of CaMKII inhibitors (KN-93 and AIP). Increased postrest twitches after CaMKII inhibition indicated an improved sarcoplasmic reticulum (SR) Ca(2+) loading. This was confirmed in isolated myocytes by a reduced SR Ca(2+) spark frequency and hence SR Ca(2+) leak, resulting in increased SR Ca(2+) load when inhibiting CaMKII. Ryanodine receptor type 2 phosphorylation at Ser2815, which is known to be phosphorylated by CaMKII thereby contributing to SR Ca(2+) leak, was found to be markedly reduced in KN-93-treated trabeculae. Interestingly, CaMKII inhibition did not influence contractility in nonfailing sheep trabeculae. CONCLUSIONS: The present study shows for the first time that CaMKII inhibition acutely improves contractility in human HF where CaMKIIδ expression is increased. The mechanism proposed consists of a reduced SR Ca(2+) leak and consequently increased SR Ca(2+) load. Thus, CaMKII inhibition appears to be a possible therapeutic option for patients with HF and merits further investigation.
Abstract: Diffuse atherosclerosis of the anterior descending artery may require unconventional surgical treatment to increase graft flow. A 74-year-old man with severe, diffuse 3-vessel-coronary artery disease was presented to our institution with progredient angina pectoris symptoms. Intraoperatively, the revascularization of the left anterior descending coronary artery (LAD) was technically challenging because of the extremely calcified coronary artery disease; therefore we performed the longest endarterectomy of the LAD that has thus far been described.
Abstract: Hemodynamic function may be depressed in the early postoperative stages after cardiac surgery. The aim of this study was the analysis of the myocardial contractility in neonates after cardiopulmonary bypass (CPB) and mild hypothermia.
Abstract: Hyperhidrosis (primary or secondary) describes a disorder of excessive sweating. It has a significant negative impact on quality of life and affects nearly 1% of the population living in the United Kingdom (UK). Axillary involvement is the most common affecting 80% of cases. A common link to these disorders is an extreme non-thermoregulatory sympathetic stimulus of exocrine sweat glands, mostly due to emotional stimuli. Non-surgical treatment involves topical medication, iontophoresis and systemic anti-cholinergics. More recently the use of intradermal botulinum toxin has gained popularity. Surgical treatment reserved for severe cases, not responding to conservative management involves local excision, curettage and thoracoscopic sympathectomy. Evolving concepts for treatment, risks and benefits are discussed in the paper herein.
Abstract: We present a case of a 77-year old female who had undergone a coronary artery bypass grafting with an aortic valve replacement and developed three month later a Methicillin-Resistant Staphylococcus aureus (MRSA) sternal wound infection which was successful treated with Daptomycin combined with vacuum-assisted closure (VAC).
Abstract: OBJECTIVE: Hypertrophic obstructive cardiomyopathy (HOCM) is treated by surgical myectomy or transcoronary ablation of septal hypertrophy (TASH). The aim of this study was to visualize the feasibility, success and short-term results of TASH on the basis of cardiac MRI (CMR) in comparison with cardiac catheterization and echocardiography. METHODS: In this in vivo study, nine patients with HOCM were treated with TASH. Patients were evaluated by transthoracic echocardiography, invasive cardiac angiography and CMR. Follow-up examinations were carried out after 1, 3 and 12 months. MR imaging was performed on a 1.5-T scanner. All images were processed using the semiautomatic Argus software and were evaluated by an attending thoracic radiologist and cardiologist. RESULTS: The echocardiographic pressure gradient (at rest) was 69.3 +/- 15.3 mmHg before and 22.1 +/- 5.7 mmHg after TASH (P < 0.01, n = 9). The flux acceleration over the aortic valve examined (V (max)) was 5.1 +/- 0.6 m/s before and 3.4 +/- 0.3 m/s after the TASH procedure (P < 0.05). Also, there was a decrease of septum thickness from 22.0 +/- 1.2 to 20.2 +/- 1.0 mm (P < 0.05) after 6 +/- 3 weeks. The invasively assessed pressure gradient at rest was reduced from 63.7 +/- 15.2 to 21.2 +/- 11.1 mmHg (P < 0.01) and the post-extrasystolic gradient was reduced from 138.9 +/- 12.7 to 45.6 +/- 16.5 mmHg (P < 0.01). All differences as well as the quantity of injected ethanol were plotted against the size or amount of scar tissue as assessed in the MRI. There was a statistically significant correlation between the post-extrasystolic gradient decrease and the amount of scar tissue (P = 0.03, r (2) = 0.5). In addition, the correlation between the quantity of ethanol and scar tissue area was highly significant (P < 0.01, r (2) = 0.6), whereas the values for the gradient deviation (P = 0.10, r (2) = 0.34), DeltaV (max) (P = 0.12, r (2) = 0.31), as well as the gradient at rest (P = 0.27, r (2) = 0.17) were not significant. CONCLUSION: TASH was consistently effective in reducing the gradient in all patients with HOCM. In contrast to the variables investigated by echocardiography, the invasively measured post-extrasystolic gradient correlated much better with the amount of scar tissue as assessed by CMR. We conclude that the optimal modality to visualize the TASH effect seems to be a combination of CMR and the invasive identification of the post-extrasystolic gradient.
Abstract: The aim of this study was to investigate the prevalence of extracardiac findings diagnosed by 64-multidetector computed tomography (MDCT) examinations prior to circumferential pulmonary vein (PV) ablation of atrial fibrillation (AF). A total of 158 patients (median age, 60.5 years; male 68%) underwent 64-MDCT of the chest and upper abdomen to characterize left atrial and PV anatomy prior to AF ablation. MDCT images were evaluated by a thoracic radiologist and a cardiologist. For additional scan interpretation, bone, lung, and soft tissue window settings were used. CT scans with extra-cardiac abnormalities categorized for the anatomic distribution and divided into two groups: Group 1-exhibiting clinically significant or potentially significant findings, and Group 2-patients with clinically non-significant findings. Extracardiac findings (n = 198) were observed in 113/158 (72%) patients. At least one significant finding was noted in 49/158 patients (31%). Group 1 abnormalities, such as malignancies or pneumonias, were found in 85/198 findings (43%). Group 2 findings, for example mild degenerative spine disease or pleural thickening, were observed in 113/198 findings (72%). 74/198 Extracardiac findings were located in the lung (37%), 35/198 in the mediastinum (18%), 8/198 into the liver (4%) and 81/198 were in other organs (41). There is an appreciable prevalence of prior undiagnosed extracardiac findings detected in patients with AF prior to PV-Isolation by MDCT. Clinically significant or potentially significant findings can be expected in ~40% of patients who undergo cardiac MDCT. Interdisciplinary trained personnel is required to identify and interpret both cardiac and extra cardiac findings.
Abstract: Minimally-invasive approaches have become increasingly important in cardiac valve surgery. Smaller incisions have become commonplace in many major centers. We reviewed the existing literature and present the current state-of-the-art of minimally-invasive valve operations in this paper.
Abstract: Purpose: The aim of this study was to analyze systematically the morphology of aortal segments of Type A dissection. Methods: Nineteen patients were operated on for Type A dissection in the Department of Thoracic, Cardiac, and Vascular Surgery in Goettingen, Germany, from January 2002 to January 2005. All diagnoses were confirmed by transesophageal echocardiography and computed tomography of the chest. All taken aortic segments were examined by the conventional histological and electron microscopical method. Results: Besides subadventitial hyperplasia of collagen filaments, the preparations showed hyperplasia of endothelial cells with loose cellular junctions, desquamation of endothelial cells, and morphological changes of endothelial cells with villius development, as well as signs of aortitis. Conclusion: The present results arouse suspicion of local inflammation of the aortic wall, but with moderate progress under strong hyperplasia. Because of rupture of the intima, the inflammation appears as an acute disease.
Abstract: Cellular and mechanical treatment to prevent heart failure each holds therapeutic promise but together have not been reported yet. The goal of the present study was to determine whether combining a cardiac support device with cell-based therapy could prevent adverse left ventricular remodeling, more than either therapy alone.
Abstract: Heart failure is one of the fastest-growing epidemics worldwide in health care today. Although a wide variety of animal models exist to create chronic heart failure, there are few truly successful, reproducible models with ischemic dilation and mitral regurgitation. Six healthy sheep (36 ± 5 kg) underwent multiple, strategic coronary artery ligations on the left ventricle (LV). Six to eight ligations were performed transmurally on three of four segments of the LV: anterior, lateral, and posterior. Side branches of the left anterior descending and circumflex arteries were ligated to create multiple, patchy areas of myocardial infarction. Cardiac global and regional systolic function was assessed by echocardiography and cardiac magnetic resonance imaging (MRI). The extent, the characteristics, and the location of the myocardial infarction were qualitatively and quantitatively assessed by late gadolinium enhancement imaging. The overall mortality rate was 16.7% (1/6 animals). Animals who survived showed a significantly reduced ejection fraction (mean 60 ± 5% to 28 ± 7%; P < 0.05); additionally, two out of the remaining five (40%) animals developed mild to moderate mitral regurgitation quantified by cardiac MRI. Furthermore, each animal developed clinical signs of heart failure (tachycardia, dyspnea, and tachypnea) consistent with global, dilated cardiomyopathy noted on MRI. Creating and reproducing a model of global, ischemic cardiomyopathy with functional mitral regurgitation is an arduous task. We have developed a promising model of ischemic heart failure using multiple ligations, which mimics the sequelae of human cardiomyopathy. Our proposed model is highly effective, reproducible, and may be used for experimental research on heart failure (cardiac assist devices, heart transplant, etc.).
Abstract: Heart failure is one of the fastest-growing epidemics worldwide in health care today. Although a wide variety of animal models exist to create chronic heart failure, there are few truly successful, reproducible models with ischemic dilation and mitral regurgitation. Six healthy sheep (36 ± 5 kg) underwent multiple, strategic coronary artery ligations on the left ventricle (LV). Six to eight ligations were performed transmurally on three of four segments of the LV: anterior, lateral, and posterior. Side branches of the left anterior descending and circumflex arteries were ligated to create multiple, patchy areas of myocardial infarction. Cardiac global and regional systolic function was assessed by echocardiography and cardiac magnetic resonance imaging (MRI). The extent, the characteristics, and the location of the myocardial infarction were qualitatively and quantitatively assessed by late gadolinium enhancement imaging. The overall mortality rate was 16.7% (1/6 animals). Animals who survived showed a significantly reduced ejection fraction (mean 60 ± 5% to 28 ± 7%; P < 0.05); additionally, two out of the remaining five (40%) animals developed mild to moderate mitral regurgitation quantified by cardiac MRI. Furthermore, each animal developed clinical signs of heart failure (tachycardia, dyspnea, and tachypnea) consistent with global, dilated cardiomyopathy noted on MRI. Creating and reproducing a model of global, ischemic cardiomyopathy with functional mitral regurgitation is an arduous task. We have developed a promising model of ischemic heart failure using multiple ligations, which mimics the sequelae of human cardiomyopathy. Our proposed model is highly effective, reproducible, and may be used for experimental research on heart failure (cardiac assist devices, heart transplant, etc.).
Abstract: Ventricular assist device (VAD) support inpatients with a prosthetic heart valve had previously been considered a relative contraindication due to an increased risk of thromboembolic complications. We report our clinical experience of VAD implantation in patients with prosthetic heart valves, including both mechanical and bioprosthetic valves. The clinical records of 133 consecutive patients who underwent VAD implantation at a single institution from January 2002 through June 2009 were retrospectively reviewed. Six of these patients had a prosthetic valve in place at the time of device implantation. Patient demographics,operative characteristics, and postoperative complications were reviewed.Of the six patients,four were male.The mean age was 57.8 years (range 35–66 years). The various prosthetic cardiac valves included a mechanical aortic valve (n = 2), a bioprosthetic aortic valve (n = 3), and a mechanical mitral valve (n = 1).The indications for VAD support included bridge to transplantation (n = 2), bridge to recovery (n = 1), and postcardiotomy ventricular failure(n = 3). Three patients underwent left ventricular assist device placement and three received a right ventricular assist device. Postoperatively, standard anticoagulation management began with a heparin infusion (if possible)followed by oral anticoagulation.The 30-day mortality was50% (3/6). The mean duration of support among survivors was 194.3 days (range 7–369 days) compared with 16.0 days(range 4–29 days) for nonsurvivors. Of the three survivors,two were successfully bridged to heart transplantation and one recovered native ventricular function.Among the three nonsurvivors,acute renal failure developed in each case, and two developed heparin-induced thrombocytopenia. This study suggests that VAD placement in patients with a prosthethic heart valve, either mechanical or bioprosthetic,appears to be a reasonable option.
Abstract: Drowning and near-drowning is often associated with severe hypothermia requiring active core rewarming.We performed rewarming by cardiopulmonary bypass(CPB). Between 1987 and 2007, 13 children (9 boys and 4 girls) with accidental hypothermia were rewarmed by extracorporeal circulation (ECC) in our institution. The average age of the patients was 3.2 years. Resuscitation was started immediately upon the arrival of the rescue team and was continuously performed during the transportation.All patients were intubated and ventilated. Core temperature at admission ranged from 20 to 29°C (mean 25.3°C). Connection to the CPB was performed by thoracic (9 patients) or femoral/iliac means (4 patients). Restoration of circulation was achieved in 11 patients (84.6%). After CPB termination two patients needed an extracorporeal membrane oxygenation system due to severe pulmonary edema.Five patients were discharged from hospital after prolonged hospital stay. During follow-up, two patients died(10 and 15 months, respectively) of pulmonary complications and one patient was lost to follow-up. The two remaining survivors were without neurological deficit.Modes of rewarming, age, sex, rectal temperature, and serum electrolytes did not influence mortality. In conclusion,drowning and near-drowning with severe hypothermia remains a challenging emergency. Rewarming by ECC provides efficient rewarming and full circulatory support.Although nearly half of the children may survive after rewarming by ECC, long-term outcome is limited by pulmonary and neurological complications.
Abstract: Training of cardiothoracic surgeons in Europe and the United States has expanded to incorporate new operative techniques and requirements. The purpose of this study was to compare the current structure of training programs in the United States and Germany.
Abstract: Friedreich's ataxia (FRA) is an autosomal recessive disease of the central nervous system that is associated with familial cardiomyopathy. Cardiac involvement is seen in more than 90% of the patients and is the most common cause of death in these patients. We present a case series and discuss the indications for implantable cardioverter defibrillator (ICD) implantation in FRA with review of the literature. Five pediatric patients who suffer from FRA (four female and one male, mean age 17.4 years) underwent ICD implantation between 2007 and 2008 in the University Hospital of Goettingen. The diagnosis of FRA was established by standard clinical criteria and proven in each case by genotyping at the frataxin locus. The time from diagnosis to ICD implantation was 10.4±1.73 years (range 8-15 years). All patients received transvenous lead systems. There were no intraoperative and postoperative complications. At the latest follow-up, the neuromuscular symptoms exhibited no further progress and no ICD activations were noticed. Only minor repolarization changes were seen on electrocardiogram. All patients had normal echocardiographic findings and no angina has been reported. Coronary angiographies were normal. It is evident that many FRA patients develop ventricular dysfunction. In the absence of a definitive surgical cure an ICD is generally indicated in young patients with hemodynamically significant sustained ventricular tachyarrhythmias for prevention of sudden cardiac death. Our experience implies the safe use of ICD in children with FRA.
Abstract: Low cardiac output (LCO) after corrective surgery remains a serious complication in pediatric congenital heart diseases (CHD). In the case of refractory LCO, extra corporeal life support (ECLS) extra corporeal membrane oxygenation (ECMO) or ventricle assist devices (VAD) is the final therapeutic option. In the present study we have reviewed the outcomes of pediatric patients after corrective surgery necessitating ECLS and compared outcomes with pediatric patients necessitating ECLS because of dilatated cardiomyopathy (DCM).
Abstract: Several genetic polymorphisms have been identified to play a role in the occurrence and progression of renal dysfunction after cardiac surgery with cardiopulmonary bypass (CPB). Recently, it was demonstrated that the T allele of SNP rs1617640 in the promoter of the erythropoetin (EPO) gene is significantly associated with proliferative diabetic retinopathy (PDR) and end-stage renal disease (ESRD) due to increased EPO expression. This disease risk-associated gene and its potential pathway mediating severe microvascular complications in T-allele carriers could also play a role on renal dysfunction in patients who underwent cardiac surgery with CPB. We hypothesized that the patients' ability to produce increased EPO concentrations will affect morbidity and mortality after CPB. We conducted a prospective single center study between April 2006 and May 2007. In 481 patients who underwent cardiac surgery with CPB we prospectively examined the SNP rs1617640 in the promoter of the EPO gene by DNA sequencing. The patients were grouped according to their genotype (GG, GT, and TT). The genotype distribution of SNP rs1617640 in the promoter of the EPO gene was 36% (TT), 49% (TG), and 15% (GG). There was no difference in age, body mass index, gender, CPB time, or length of stay in intensive care unit. The hospitalization was irrespective of the patients' genotypes. The baseline creatinine in the TT group was 0.2 points higher than in the other groups; however this was without statistical significance in the multivariate analysis. No significant difference was shown in Euroscore, the Simplified Acute Physiology Score II, the Acute Physiology and Chronic Health Evaluation Score II, Acute Renal Failure Score, or the Risk, Injury, Failure, Loss of Kidney Function Score. The mortality was equal across the genotypes. However, an association between the TT genotype and acute renal replacement therapy (P=0.03), intra-aortic balloon pump usage (P=0.02), and serum creatine phosphokinase-MB increase (P=0.03) were observed after cardiac surgery. Our analysis suggests that the risk allele (T) of rs1617640 plays a role in the development of renal dysfunction after cardiac surgery with CPB. Patients with the TT risk allele required more frequent acute renal replacement therapy. Since our result is close to the border of significance, this hypothesis should be investigated in larger prospective studies with long-term follow-up to emphasize this polymorphism as a potential risk factor.
Abstract: We established a stable and reproducible animal model of chronic heart failure (CHF) in sheep to investigate biomolecular changes. Therefore, two biomarkers, adenosine monophosphate-activated protein kinase (AMPK) and vascular endothelial growth factor-A (VEGF-A) were examined to reveal their role during chronic ischemic conditions of the heart. AMPK was studied because it plays an important role in cellular energy homeostasis and its upregulation is associated with myocardial ischemia, whereas VEGF-A was studied because it acts as an important signaling protein for neoangiogenesis. We examined 15 juvenile sheep (mean weight, 78±4kg; control, n=3; ShamOP, n=2; coronary microembolization [CME], n=10). CHF was induced under fluoroscopic guidance by multiple sequential microembolizations (MEs) through bolus injection of polysterol microspheres (90µm, n=25.000) into the left main coronary artery. CME was repeated up to three times at 2- to 3-week intervals until animals started to develop stable signs of CHF. All animals were followed for 3 months. Phosphorylation of AMPK, marking the activated protein form, was detected by Western blotting. VEGF-A and vascular endothelial growth factor-receptor 2 (VEGF-R2) mRNA were detected by real-time polymerase chain reaction. Glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) was used as a reference housekeeping gene. All 10 CHF animals developed clinical signs of CHF as indicated by a significant decrease of cardiac output, decreased ejection fraction, as well as occurrence of tachycardia and tachypnoea. Western blots showed significant phosphorylation of AMPK in CME animals compared to the control group (phospho-adenosine monophosphate-activated protein kinase α) (GAPDH control: 0.0, CME left ventricle [LV]: 0.39±0.20, CME right ventricle [RV]: 0.53±0.30; P<0.05). VEGF-A and VEGF-R2 expression in CME animal myocardium was within the range of the control group, but this data did not reach statistical significance due to the small size of this group. While microinjection was performed into the left main coronary artery, phosphorylation of AMPK and expression of VEGF-A and VEGF-R2 were significantly higher in the RV than in the LV. Multiple sequential intracoronary MEs can effectively induce myocardial dysfunction with clinical and biomolecular signs of chronic ischemic cardiomyopathy. Quantitative analysis of biomolecular markers showed a significantly higher phosphorylation of AMPK in CHF animals compared with control myocardium.
Abstract: OBJECTIVES: We investigated changes in Na(+) currents (I(Na)) in permanent (or chronic) atrial fibrillation (AF) and the effects of I(Na) inhibition using ranolazine (Ran) on arrhythmias and contractility in human atrial myocardium. BACKGROUND: Electrical remodeling during AF is typically associated with alterations in Ca(2+) and K(+) currents. It remains unclear whether I(Na) is also altered. METHODS: Right atrial appendages from patients with AF (n = 23) and in sinus rhythm (SR) (n = 79) were studied. RESULTS: Patch-clamp experiments in isolated atrial myocytes showed significantly reduced peak I(Na) density ( approximately 16%) in AF compared with SR, which was accompanied by a 26% lower expression of Nav1.5 (p < 0.05). In contrast, late I(Na) was significantly increased in myocytes from AF atria by approximately 26%. Ran (10 mumol/l) decreased late I(Na) by approximately 60% (p < 0.05) in myocytes from patients with AF but only by approximately 18% (p < 0.05) in myocytes from SR atria. Proarrhythmic activity was elicited in atrial trabeculae exposed to high [Ca(2+)](o) or isoprenaline, which was significantly reversed by Ran (by 83% and 100%, respectively). Increasing pacing rates from 0.5 to 3.0 Hz led to an increase in diastolic tension that could be significantly decreased by Ran in atria from SR and AF patients. CONCLUSIONS: Na(+) channels may contribute to arrhythmias and contractile remodeling in AF. Inhibition of I(Na) with Ran had antiarrhythmic effects and improved diastolic function. Thus, inhibition of late I(Na) may be a promising new treatment option for patients with atrial rhythm disturbances and diastolic dysfunction.
Abstract: AIM: In pediatric patients with congenital heart disease low cardiac output (LCO) is the principal complication after corrective heart surgery. In LCO refractory to all therapeutic options, mechanical circulatory support is the final method to keep these patients alive. In this present study the authors reviewed the outcome of pediatric patients who required mechanical circulatory support after corrective surgery with extracorporeal membrane oxygenation or ventricle assisted devices (VAD). METHODS: A retrospective single centre consecutive cohort study was carried out in children who required different mechanical circulatory support indicated by postcardiotomy low output syndrome between 1991 and 2004. A total of 20 patients received extracorporeal life support. The indications for surgery were: 12 transposition of great arteries, 1 Bland-White-Garland syndrome, 3 tetralogy of Fallot, 1 hypoplasia of aortic arch, 1 total anomalous pulmonary vein connection, and 2 ventricle septum defect. RESULTS: Mean age was 1.29 years. Mean duration of assist was 8.87 days. Seven patients out of 20 survived, six could be discharged after myocardial recovery from LCO and one could be discharged after successful heart transplantation. The overall mortality in patients with extracorporeal life support was 65%. The causes of death were multiorgan failure and bleeding in one case was a VAD related complication. CONCLUSION: The use of extracorporeal life support (ECLS) shows a high mortality rate. However, ECLS can still help to keep some of those patients alive. Mechanical support devices are the ultimate chance to save time, to increase survival and to bridge the time until heart transplantation.
Abstract: A surgical fire is a serious complication not previously described in the literature with regard to the thoracic cavity. We report a case in which an intrathoracic fire developed following an air leak combined with high pressure oxygen ventilation in a patient with severe chronic obstructive pulmonary disease. The patient presented to our institution with diffuse coronary artery disease and angina pectoris. He was treated with coronary artery bypass graft surgery, including left internal thoracic artery harvesting. Additionally to this rare presentation of an intrathoracic fire, a brief review of surgical fires is included to this paper.
Abstract: PURPOSE OF REVIEW: Aortic valve-sparing (AVS) operations include an armamentarium of procedures, which preserve the aortic cusps in aortic root dilation with aortic insufficiency. The purpose of this review article is to specifically outline the surgical indications, to describe the various techniques, and to present results from the most current series in AVS operations. RECENT FINDINGS: In the worldwide literature, there is promising data on AVS operations. Patients undergoing AVS operations not only have better long-term survival but also appear to have a reduced risk of aortic insufficiency and thromboembolic complications. SUMMARY: AVS operations are an excellent option for patients with an aortic root aneurysm and normal/minimally diseased aortic cusps.
Abstract: Functional mitral regurgitation (MR) is a common clinical entity which will likely increase in the future due to predicted demographic changes. It is also associated with poor long-term survival. The anatomic structure of the mitral valve apparatus is complex and consists of several components, each of which can be affected by a variety of diseases resulting in MR. In primary MR, the valvular incompetence is caused by compromised or structurally disrupted components of the valve apparatus; the valve in functional MR is structurally normal, with the regurgitation resulting from failure of coaptation of the mitral valve leaflets without coexisting structural changes of the valve itself. Therefore, we defined functional MR as a systolic retrograde flow from the left ventricle into the left atrium due to reduction and/or elimination of the normal systolic coaptation of the mitral valve leaflets. A slow progression of the symptoms is typical for this valve disease and often ends in irreversible left ventricular dysfunction. The pathophysiology and treatment of functional MR are quite complex. This article reviews and summarizes the existing literature, with a focus on the pathophysiology and current treatment of functional MR.
Abstract: In heart failure, intracellular Ca2+ leak from cardiac ryanodine receptors (RyR2s) leads to a loss of Ca2+ from the sarcoplasmic reticulum (SR) potentially contributing to decreased function. Experimental data suggest that the 1,4-benzothiazepine K201 (JTV-519) may stabilise RyR2s and thereby reduce detrimental intracellular Ca2+ leak. Whether K201 exerts beneficial effects in human failing myocardium is unknown. Therefore, we have studied the effects of K201 on muscle preparations from failing human hearts. K201 (0.3 microM; extracellular [Ca2+]e 1.25 mM) showed no effects on contractile function and micromolar concentrations resulted in negative inotropic effects (K201 1 microM; developed tension -9.8 +/- 2.5% compared to control group; P < 0.05). Interestingly, K201 (0.3 microM) increased the post-rest potentiation (PRP) of failing myocardium after 120 s, indicating an increased SR Ca2+ load. At high [Ca2+]e concentrations (5 mmol/L), K201 increased PRP already at shorter rest intervals (30 s). Strikingly, treatment with K201 (0.3 microM) prevented diastolic dysfunction (diastolic tension at 5 mmol/L [Ca2+]e normalised to 1 mmol/L [Ca2+]e: control 1.26 +/- 0.06, K201 1.01 +/- 0.03, P < 0.01). In addition at high [Ca2+]e) K201 (0.3 microM) treatment significantly improved systolic function [developed tension +27 +/- 8% (K201 vs. control); P < 0.05]. The beneficial effects on diastolic and systolic functions occurred throughout the physiological frequency range of the human heart rate from 1 to 3 Hz. Upon elevated intracellular Ca2+ concentration, systolic and diastolic contractile functions of terminally failing human myocardium are improved by K201.
Abstract: Adenosine monophosphate - activated kinase (AMPK) plays a key role in the coordination of the heart's anabolic and catabolic pathways. It induces a cellular cascade at the center of maintaining energy homeostasis in the cardiomyocytes.. The activated AMPK is a heterotrimeric protein, separated into a catalytic α - subunit (63kDa), a regulating β - subunit (38kDa) and a γ - subunit (38kDa), which is allosterically adjusted by adenosine triphosphate (ATP) and adenosine monophosphate (AMP). The actual binding of AMP to the γ - subunit is the step which activates AMPK. AMPK serves also as a protein kinase in several metabolic pathways of the heart, including cellular energy sensoring or cardiovascular protection. The AMPK cascade represents a sensitive system, activated by cellular stresses that deplete ATP and acts as an indicator of intracellular ATP/AMP. In the context of cellular stressors (i.e. hypoxia, pressure overload, hypertrophy or ATP deficiency) the increasing levels of AMP promote allosteric activation and phosphorylation of AMPK. As the concentration of AMP begins to increase, ATP competitively inhibits further phosphorylation of AMPK. The increase of AMP may also be induced either from an iatrogenic emboli, percutaneous coronary intervention, or from atherosclerotic plaque rupture leading to an ischemia in the microcirculation. To modulate energy metabolism by phosphorylation and dephosphorylation is vital in terms of ATP usage, maintaining transmembrane transporters and preserving membrane potential. In this article, we review AMPK and its role as an important regulatory enzyme during periods of myocardial stress, regulating energy metabolism, protein synthesis and cardiovascular protection.
Abstract: AIM: The induction of mild hypothermia (MH; 33 degrees C) has become the guideline therapy to attenuate hypoxic brain injury after out-of-hospital cardiopulmonary resuscitation. While MH exerts a positive inotropic effect in vitro, MH reduces cardiac output in vivo and is thus discussed critically when severe cardiac dysfunction is present in patients. We thus assessed the effect of MH on the function of the normal heart in an in vivo model closely mimicking the clinical setting. METHODS: Ten anaesthetized, female human-sized pigs were acutely catheterized for measurement of pressure-volume loops (conductance catheter), cardiac output (Swan-Ganz catheter) and for vena cava inferior occlusion. Controlled MH (from 37 to 33 degrees C) was induced by a vena cava inferior cooling catheter. RESULTS: With MH, heart rate (HR) and whole body oxygen consumption decreased, while lactate levels remained normal. Cardiac output, left ventricular (LV) volumes, peak systolic and end-diastolic pressure and dP/dt(max) did not change significantly. Changes in dP/dt(min) and the time constant of isovolumetric relaxation demonstrated impaired active relaxation. In addition, MH prolonged the systolic and shortened the diastolic time interval. Pressure-volume analysis revealed increased end-systolic and end-diastolic stiffness, indicating positive inotropy and reduced end-diastolic distensibility. Positive inotropy was preserved during pacing, while LV end-diastolic pressure increased and diastolic filling was substantially impaired due to delayed LV relaxation. CONCLUSION: MH negatively affects diastolic function, which, however, is compensated for by decreased spontaneous HR. Positive inotropy and a decrease in whole body oxygen consumption warrant further studies addressing the potential benefit of MH on the acutely failing heart.
Abstract: We report a case of a male patient who received an implantation of a Starr-Edwards-caged-ball-valve-prosthesis in 1967. The surgery and postoperative course were without complications and the patient recovered well after the operation. For the next four decades, the patient remained asymptomatic--no restrictions on his lifestyle and without any complications. In 2006, 39 years after the initial operation, we performed a Bentall-Procedure to treat an aortic ascendens aneurysm with diameters of 6.0 x 6.5 cm: we explanted the old Starr-Edwards-aortic-caged-ball-valve-prosthesis and replaced the ascending aorta with a 29 mm St.Jude Medical aortic-valve-composite-graft and re-implanted the coronary arteries.This case represents the longest time period between Starr-Edwards-caged-ball-valve-prosthesis-implantation and Bentall-reoperation, thereby confirming the excellent durability of this valve.
Abstract: The optimal treatment of congenital aortic valve lesions is a controversial issue. This study was performed to evaluate the outcome after surgical treatment of aortic valve lesions in congenital aortic valve disease. Between the years of 2000 and 2008, 61 patients (mean age: 12.6 +/- 9.6 years, range: 1 day to 40 years) underwent aortic valve surgery for congenital aortic valve disease. Twenty-four patients had undergone previous cardiovascular operations. Indications for surgery were aortic regurgitation in 14.7% (n = 9), aortic stenoses in 26.2% (n = 16), and mixed disease in 59.1% (n = 36). The Ross procedure was performed in 37.7% (n = 23), aortic valve replacement with biological or mechanical prostheses in 29.5% (n = 18). Concomitant procedures were performed in 91.8% (n = 56) due to associated congenital cardiac defects. The overall mortality rate was 5%. Six patients needed reoperation. Implantation of permanent pacemakers occurred in six patients for permanent atrioventricular block. At the latest clinical evaluation, all survivors are in New York Heart Association class I-II and are living normal lives. Aortic valve surgeries in patients with congenital heart disease have had low mortality and morbidity rates in our series. Surgical technique as well as timing should be tailored for each patient. Aortic valve replacement should be delayed until the implantation of an adult-sized prosthesis is possible.
Abstract: AIM: The endothelial nitric oxide (eNOS) gene T-786C polymorphism may influence as a genetic risk factor cardiovascular diseases and shows association with cardiovascular mortality. We hypothesized that this polymorphism may lead to increase mortality and morbidity after cardiac surgery with cardiopulmonary bypass (CPB). METHODS: In 500 patients who underwent cardiac surgery with CPB we investigated the eNOS T-786C polymorphism by DNA-sequencing. The patients were grouped according to their genotype in three groups (TT, TC, and CC). RESULTS: The overall genotype distribution of T-786C polymorphism was TT=41.6%, TC=51.2%, and CC=7.2% respectively. The groups did not differ in age and gender. No significance was shown in preoperative risk factors, excluding peripheral disease (P=0.03). No difference was shown in Euroscore, APACHE II, and SAPS II. The usage of norepinephrine (P=0.03) and nitroglycerine (P=0.01) was significant higher in TC allele carrier. The mortality was quite uniform across elective and urgent subgroup. However, we found a significant difference concerning mortality and emergency cardiac procedures in homozygous C-allele carrier (P=0.014). CONCLUSION: The present study demonstrates that this polymorphism contributes to a higher prevalence of postoperative mortality after emergency cardiac surgery. Thus, the eNOS T-786C polymorphism could serve as a possibility to differentiate high risk subgroups in heterogeneous population of individuals with cardiac diseases who need cardiac surgery with CPB.
Abstract: Although a large variety of animal models for acute ischemia and acute heart failure exist, valuable models for studies on the effect of ventricular assist devices in chronic heart failure are scarce. We established a stable and reproducible animal model of chronic heart failure in sheep and aimed to investigate the hemodynamic changes of this animal model of chronic heart failure in sheep. In five sheep (n = 5, 77 +/- 2 kg), chronic heart failure was induced under fluoroscopic guidance by multiple sequential microembolization through bolus injection of polysterol microspheres (90 microm, n = 25.000) into the left main coronary artery. Coronary microembolization (CME) was repeated up to three times in 2 to 3-week intervals until animals started to develop stable signs of heart failure. During each operation, hemodynamic monitoring was performed through implantation of central venous catheter (central venous pressure [CVP]), arterial pressure line (mean arterial pressure [MAP]), implantation of a right heart catheter {Swan-Ganz catheter (mean pulmonary arterial pressure [PAP mean])}, pulmonary capillary wedge pressure (PCWP), and cardiac output [CO]) as well as pre- and postoperative clinical investigations. All animals were followed for 3 months after first microembolization and then sacrificed for histological examination. All animals developed clinical signs of heart failure as indicated by increased heart rate (HR) at rest (68 +/- 4 bpm [base] to 93 +/- 5 bpm [3 mo][P < 0.05]), increased respiratory rate (RR) at rest (28 +/- 5 [base] to 38 +/- 7 [3 mo][P < 0.05]), and increased body weight 77 +/- 2 kg to 81 +/- 2 kg (P < 0.05) due to pleural effusion, peripheral edema, and ascites. Hemodynamic signs of heart failure were revealed as indicated by increase of HR, RR, CVP, PAP, and PCWP as well as a decrease of CO, stroke volume, and MAP 3 months after the first CME. Multiple sequential intracoronary microembolization can effectively induce myocardial dysfunction with clinical and hemodynamic signs of chronic ischemic cardiomyopathy. The present model may be suitable in experimental work on heart failure and left ventricular assist devices, for example, for studying the impact of mechanical unloading, mechanisms of recovery, and reverse remodeling.
Abstract: BACKGROUND: Despite the existence of controversial debates on the efficiency of coronary endarterectomy (CE), it is still used as an adjunct to coronary artery bypass grafting (CABG). This is particularly true in patients with endstage coronary artery disease. Given the improvements in cardiac surgery and postoperative care, as well as the rising number of elderly patient with numerous co-morbidities, re-evaluating the pros and cons of this technique is needed. METHODS: Patient demographic information, operative details and outcome data of 104 patients with diffuse calcified coronary artery disease were retrospectively analyzed with respect to functional capacity (NYHA), angina pectoris (CCS) and mortality. Actuarial survival was reported using a Kaplan-Meyer analysis. RESULTS: Between August 2001 and March 2005, 104 patients underwent coronary artery bypass grafting (CABG) with adjunctive coronary endarterectomy (CE) in the Department of Thoracic-, Cardiac- and Vascular Surgery, University of Goettingen. Four patients were lost during follow-up. Data were gained from 88 male and 12 female patients; mean age was 65.5 +/- 9 years. A total of 396 vessels were bypassed (4 +/- 0.9 vessels per patient). In 98% left internal thoracic artery (LITA) was used as arterial bypass graft and a total of 114 vessels were endarterectomized. CE was performed on right coronary artery (RCA) (n = 55), on left anterior descending artery (LAD) (n = 52) and circumflex artery (RCX) (n = 7). Ninety-five patients suffered from 3-vessel-disease, 3 from 2-vessel- and 2 from 1-vessel-disease. Closed technique was used in 18%, open technique in 79% and in 3% a combination of both. The most frequent endarterectomized localization was right coronary artery (RCA = 55%). Despite the severity of endstage atherosclerosis, hospital mortality was only 5% (n = 5). During follow-up (24.5 +/- 13.4 months), which is 96% complete (4 patients were lost caused by unknown address) 8 patients died (cardiac failure: 3; stroke: 1; cancer: 1; unknown reasons: 3). NYHA-classification significantly improved after CABG with CE from 2.2 +/- 0.9 preoperative to 1.7 +/- 0.9 postoperative. CCS also changed from 2.4 +/- 1.0 to 1.5 +/- 0.8 CONCLUSION: Early results of coronary endarterectomy are acceptable with respect to mortality, NYHA & CCS. This technique offers a valuable surgical option for patients with endstage coronary artery disease in whom complete revascularization otherwise can not be obtained. Careful patient selection will be necessary to assure the long-term benefit of this procedure.
Abstract: When a left ventricular aneurysm leads to pulmonary congestive symptoms, aneurysmectomy may provide relief. This retrospective study included 269 patients who underwent aneurysmectomy between 1993 and 2002, by the classic Cooley operation in 164 and by Dor ventriculoplasty in 105. There were no significant differences in early and late survival between groups, although the frequency of extended anteroseptal infarction was higher in patients undergoing the Dor procedure. Postoperative echocardiographic findings showed significant improvements in left ventricular function in both groups, in terms of end-diastolic and end-systolic dimensions and ejection fraction. Left ventricular aneurysmectomy significantly improved the clinical status and hemodynamic parameters of symptomatic patients. The choice of surgical technique depends on the extent of the scar segment, especially the presence of an anteroseptal scarred area. The Dor procedure is more suitable for restoring normal left ventricular geometry in patients with extensive septal infarction.
Abstract: The purpose of this article is to discuss the significance of academic collaboration within cardiovascular medicine and surgery, in both clinical and research settings, at a major academic institution in Europe.
Abstract: Due to improved outcome after surgery for congenital heart defects, children, adolescents, and grown-ups with congenital heart defects become an increasing population. In order to evaluate operative risk and early outcome after mechanical aortic valve replacement (AVR) in this population, we reviewed patients who underwent previous repair of congenital heart defects. Between July 2002 and November 2008, 15 (10 male and 5 female) consecutive patients (mean age 14.5 +/- 10.5 years) underwent mechanical AVR. Hemodynamic indications for AVR were aortic stenosis in four (27%), aortic insufficiency in eight (53%), and mixed disease in three (20%) after previous repair of congenital heart defects. All patients had undergone one or more previous cardiovascular operations due to any congenital heart disease. Concomitant cardiac procedures were performed in all of them. In addition to AVR, in two patients, a mitral valve exchange was performed. One patient received a right ventricle-pulmonary artery conduit replacement as concomitant procedure. The mean size of implanted valves was 23 mm (range 17-29 mm). There were neither early deaths nor late mortality until December 2008. Reoperations were necessary in five (33%) and included implantation of a permanent pacemaker due to complete atrioventricular block in two (15%), mitral valve replacement with a mechanical prosthesis due to moderate to severe mitral regurgitation in one (7%), aortocoronary bypass grafting due to stenosis of a coronary artery in one (7%), and in one (7%), a redo subaortic stenosis resection was performed because of a secondary subaortic stenosis. At the latest clinical evaluation, all patients were in good clinical condition without a pathological increased gradient across the aortic valve prosthesis or paravalvular leakage in echocardiography. Mechanical AVR has excellent results in patients after previous repair of congenital heart defects in childhood, even in combination with complex concomitant procedures. Previous operations do not significantly affect postoperative outcome.
Abstract: We report an unusual case of an aortic type A dissection with a corpus alienum which compresses the right ventricle. The patient successfully underwent an aortic root replacement in deep hypothermia with re-implantation of the coronary arteries using a modified Bentall procedure and the resection of the corpus alienum. Intraoperative finding reveals 3 greatly adhered gauze compresses, which were most likely forgotten in the operation 34 years ago.
Abstract: BACKGROUND: Current concepts of acute pulmonary embolism suggest that right ventricular (RV) dilatation and failure are the consequence of pressure overload-induced RV hypoperfusion and ischemia. METHODS: Sixteen human-sized hybrid pigs were instrumented for the measurement of RV and aortic pressure, aortic and right coronary artery blood flow (RCA BF), RV oxygen consumption (RV MVO(2)) and RV free wall segment length. The pulmonary artery was constricted (PAC) to increase RV peak pressure acutely 2.5-fold (from 27+/-2 to 64+/-3 mmHg, n=9), and the constriction was maintained for 6h. RESULTS: At 10 min after PAC, a RV work index (RVWI, RV pressure-segment length loops) was increased 2.3-fold, indicating an initial RV adaptation to increased afterload. At 1h, 3h and 6h after PAC, however, RVWI decreased progressively towards control levels, while RCA BF and RV MVO(2) continued to increase. The arterial-coronary venous pH difference did not increase throughout the protocol. Arterial troponin T concentration increased from 0.08+/-0.03 to 0.80+/-0.20ng/ml at 6h after PAC. None of the parameters changed in control animals (n=7). CONCLUSION: We conclude that in our model RV failure during PAC develops in spite of increased coronary blood flow and MVO(2). Thus, mechanisms different from ischemia may contribute to progressive RV failure after pulmonary embolism.
Abstract: BACKGROUND: Complications of acute myocardial infarction (AMI) with mechanical defects are associated with poor prognosis. Surgical intervention is indicated for a majority of these patients. The goal of surgical intervention is to improve the systolic cardiac function and to achieve a hemodynamic stability. In this present study we reviewed the outcome of patients with post infarction ventricular septal defect (PVSD) who underwent cardiac surgery. METHODS: We analysed retrospectively the hospital records of 41 patients, whose ages range from 48 to 81, and underwent a surgical treatment between 1990 and 2005 because of PVSD. RESULTS: In 22 patients concomitant coronary artery bypass grafting (CAGB) was performed. In 15 patients a residual shunt was found, this required re-op in seven of them. The time interval from infarct to rupture was 8.7 days and from rupture to surgery was 23.1 days. Hospital mortality in PVSD group was 32%. The mortality of urgent repair within 3 days of intractable cardiogenic shock was 100%. The mortality of patients with an anterior VSD and a posterior VSD was 29.6% vs 42.8%, respectively. All patients who underwent the surgical repair later than day 36 survived. CONCLUSION: Surgical intervention is indicated for a majority of patients with mechanical complications. Cardiogenic shock remains the most important factor that affects the early results. The surgical repair of PVSD should be performed 4-5 weeks after AMI. To improve surgical outcome and hemodynamics the choice of surgical technique and surgical timing as well as preoperative management should be tailored for each patient individually.
Abstract: OBJECTIVE: Renal dysfunction is one of the most serious complications following cardiac surgery with cardiopulmonary bypass. The causes of renal dysfunction following cardiac surgery are poorly understood. We hypothesised that T-786C endothelial NO synthase (eNOS) polymorphism may lead to an increase in the occurrence of postoperative renal dysfunction following cardiac surgery with cardiopulmonary bypass. METHODS: A total of 497 patients undergoing cardiac surgery with cardiopulmonary bypass were included in the study. The T-786C eNOS polymorphism was detected by a polymerase chain reaction. The patients were grouped on the basis of whether they were homozygous or heterozygous for the C allele (TC+CC; n=289) or only homozygous for the T allele (TT; n=208). RESULTS: No significance was demonstrated in the preoperative risk factors, with the exclusion of smoking habits (p=0.04) for the C-allele carrier. The administration of anti-lipid agents (p=0.01) and anti-arrhythmics (p=0.01) was significantly lower in the TC/CC group. The TC+CC genotype group had a significantly greater decrease in creatine clearance (p=0.024), the lowest creatine clearance (p=0.004) and more C-allele carriers received acute renal replacement therapy (p=0.04). The usage of norepinephrine (p=0.02) and dobutamine (p=0.02) was significantly higher in C-allele carriers. In the TC+CC genotype group, cross-clamp time (p=0.02) and administration of red cell transfusion (p=0.04) achieved statistically significant difference. The overall in-hospital mortality rate was 8.2% for all patients and was not significant between genotypes. CONCLUSIONS: The present findings support the hypothesis that the T-786C eNOS polymorphism may play a role in the development of renal dysfunction and increase the occurrence of renal replacement therapy following cardiac surgery with cardiopulmonary bypass. This polymorphism may be useful in stratifying the risk for the development of postoperative renal dysfunction.
Abstract: We report a case of successful treatment of postoperative saphenectomy wound infection of the upper left leg with the antibiotic drug Daptomycin.
Abstract: We report an unusual case of a 32-year old man who was treated for a hypertrophic obstructive cardiomyopathy (HOCM) with a DDD pacing with short AV delay reduction in the past. Without prior notice the patient developed ventricular fibrillation and an invasive cardiac diagnostic was performed, which revealed a myocardial bridging around of the left anterior descending artery (LAD). We suspected ischemia that could be either related to LAD artery compression or perfusion abnormalities due to AV delay reduction with related to diastolic dysfunction.
Abstract: We evaluated the newly developed miniaturized HIA microdiagonal blood pump (MDP) as a continuous flow left ventricular assist device. In a sheep model (n = 6), the MDP was implanted through left lateral thoracotomy and placed paracorporeally with inflow conduit to left atrium and outflow conduit to descending aorta. The sheep were pumped at a mean flow rate of 2.5 L/min for 7 days. Anticoagulation was applied by intravenous heparin administration. Postoperatively, activated clotting time was held stable with values of 200 seconds. During follow-up, blood samples (creatinine kinase, creatinine, glutamic-oxaloacetic transaminase (aspartate aminotransferase) (GOT), glutamate dehydrogenase (GLDH), gamma-GT, plasma-free hemoglobin, and hemoglobine) were taken daily. After 7 days, the sheep were killed for macroscopic examination. Systemic artery pressures remained stable during the whole test period. Because of operative reasons, the hemoglobin value (7.5 +/- 0.61 g/dl) decreased perioperatively, but recovered within the test period, whereas creatinine kinase increased initially after thoracotomy, but decreased to normal within days. Renal and liver functions were slightly impaired perioperatively, indicated by temporarily enhanced values of GOT, gamma-GT, GLDH, and creatinine. The MDP did not produce significant hemolysis as measured by plasma-free hemoglobin levels. Wound infections did not occur. We conclude that the MDP ran successfully as an left ventricular assist device for 7 days in sheep has potential for long-term support, and may serve as an alternative to current technologies. Presented data were not obtained in a clinical trial; however, the results are promising enough to proceed with longer duration animal studies.
Abstract: BACKGROUND: More than 50% of aortocoronary saphenous vein grafts are occluded 10 years after surgery. Intimal hyperplasia is the initial critical step in the progression toward occlusion. Internal mammary veins, which are physiologically prone to less hydrostatic pressure, may undergo an accelerated progression to intimal hyperplasia and thus be suitable for investigation of the mechanisms of aortocoronary vein graft disease. METHODS: Six minipigs underwent aortocoronary bypass grafting using standard cardiopulmonary bypass and cardioplegic arrest. Mammary vein were grafted in a reversed manner from ascending aorta to left anterior descending coronary artery (LAD). The proximal LAD was ligated, rendering the anterior left ventricle vein graft-dependent. Minipigs were killed after 4 weeks, and vein grafts were harvested. Histological and immunohistological investigation were performed with respect to morphometric analysis, endothelial damage/dysfunction (v-Willebrand-factor (vWF)), smooth muscle cells (alpha-smooth actin) and proliferation rate (proliferation marker Ki 67). RESULTS: Mean intimal area of vein grafts was increased compared to ungrafted mammary veins. Intimal hyperplasia in vein grafts was characterized by massive accumulation of smooth muscle cells with a high proliferation rate and endothelial perturbation. Significant (p = 0.001) intimal hyperplasia of the grafted mammary vein compared to the ungrafted mammary vein was found. These changes were absent in ungrafted mammary veins. CONCLUSION: The present study demonstrates a pig model of aortocoronary vein graft intimal hyperplasia which is characterized by an accelerated progression within internal mammary veins. The model is suitable to investigate the pathophysiology of aortocoronary vein graft intimal hyperplasia as well as therapeutic approaches.
Abstract: OBJECTIVE: Although a large variety of animal models for acute ischemia and acute heart failure exist, valuable models for studies on the effect of ventricular assist devices in chronic heart failure are scarce. We aimed to establish a stable and reproducible animal model of chronic heart failure in sheep. METHODS: Sheep (n=8, 77 +/- 4 kg) were anesthesized and a 5F sheath was implanted into the left carotid artery. The left main coronary artery was catheterized under flouroscopic guidance and bolus injection of polysterol microspheres (90 microm, n=25.000) was performed. Microembolization (ME) was repeated up to three times in two to three week intervals until animals started to develop stable clinical signs of heart failure. Clinical and echocardiographic data were analyzed at baseline (base) and at three months (3 mo) after first ME. All animals were followed for 3 months after first microembolization and then sacrificed for histological examination. Another four healthy sheep (79+/-6 kg) served as control animals. RESULTS: All animals developed clinical signs of heart failure as indicated by increased heart rate at rest (68+/-4 bpm (base) to 93 +/- 5 bpm (3 mo) (p<0.05)), increased respiratory rate at rest (28+/-5 (base) to 38 +/- 7 (3 mo) (p<0.05)) and increased body weight 77 +/- 2 kg to 81 +/- 2 kg (p<0.05) due to pleural effusion, peripheral edema and ascites. Echocardiographic evaluation revealed significantly an increase of left ventricular enddiastolic diameter from 46 +/- 3 mm (base) to 61 +/- 4 mm (3 mo) (p<0.05). Clinically and echocardiographically no significant changes were revealed in healthy control animals. CONCLUSIONS: We conclude that multiple sequential intracoronary microembolization can effectively induce myocardial dysfunction with clinical and echocardiographical signs of chronic ischemic cardiomyopathy. The present model may be suitable in experimental work on heart failure and left ventricular assist devices, e.g. for studying the impact of mechanical unloading, mechanisms of recovery and reverse remodeling.
Abstract: We examined data of 21 patients who were treated with selective perfusion of both renal arteries with 500 mL of 8 degrees C histidine-tryptophan-ketoglutarate (HTK) solution each for renal protection during aortic surgery. Only the data from aortic surgeries with unavoidable suprarenal aortic cross-clamping for juxtarenal or suprarenal abdominal aortic aneurysms (AAAs) or high Leriche syndrome accompanied with stenosis of renal arteries are presented. Five patients underwent immediate surgery because of perforation of an AAA; the other 16 patients went through elective surgeries. In three cases (14%) stenosis of the renal arteries was diagnosed; nevertheless, implantation of an aortorenal bypass was necessary in seven patients. In total, 14 aortorenal bypasses were implanted (five venous grafts and nine prosthesis grafts). Four (19%) patients needed catecholaminergic support to establish stable circulatory conditions; in two (9%) of these cases additional ischemia of the colon was observed and sigmoidectomy was performed. All of these four patients underwent immediate surgery, and one died after surgery because of severe sepsis. In four cases postsurgical renal insufficiency was observed. Three of these patients were admitted for emergency surgery because of their hemodynamic situation due to perforation of the AAA. None of the patients needed chronic dialysis after surgery. Whereas in all patients who underwent elective surgery the renal function remained stable as judged by postoperative serum creatinine values, in five out of seven patients with aortorenal bypass surgery the renal function improved. Perfusion with cold HTK solution offers an additional procedure to protect renal function in patients undergoing elective surgery with suprarenal cross-clamping of the aorta.
Abstract: AIM: Valuable models of chronic heart failure to perform histological studies are scarce. The authors aimed at investigating histological changes of the heart, lung, liver and kidneys in a stable and reproducible animal model of chronic heart failure in sheep. METHODS: In 8 sheep (N.=8, 77+/-2 kg) chronic heart failure was induced by multiple sequential microembolization through bolus injection of polysterol microspheres (90 microm, N=25 000) into the left main coronary artery. Microembolization (ME) was repeated up to three times in two to three week intervals until animals started to develop stable signs of heart failure. Therefore, clinical and hemodynamic parameters were measured (Troponin T, heart and respiratory rate, cardiac output) after each embolization. Clinical examination was carried out by a veterinarian. All animals were followed for 3 months after first microembolization and then euthanized for histological examination. Histological data of the heart, lung, liver and the kidneys were analyzed in hematoxylin-eosin (HE) stains (10x, 25x, 100x) at baseline (control group) and at 3 months after first ME. Additionally preparations of heart tissue were stained with Picro-Sirius-Red (PSR) for planimetric quantification. A score from 0 to 4 according to Rassler et al. (2005) was used to assess the degree of lung injury. RESULTS: All animals developed histological signs of heart failure as indicated by island-like, patchy fibrosis of the heart. Planimetric quantification (PSR stain) of the heart revealed a significant increase of the total amount of fibrosis from 8+/-2% (base) to 21+/-4% (3 months) (P<0.05), which was distributed homogeneously throughout the left ventricle (20+/-3% left ventricular [LV] anterior wall, 21+/-4% LV posterior wall, 20+/-4% septum). Histologic analysis of the lung demonstrated a moderate degree of interstitial edema and pronounced peribronchial processes of inflammation with beginning proliferation of fibrotic tissue. Liver tissue showed histological changes in terms of pericentral adiposis as sign of hypoxia in course of lacking perfusion. Signs of liver congestion could be detected histological in form of central-venous accumulation of erythrocytes and dissolution of liver tissue in proximity of the central veins. Kidney preparations illustrated loss of endothelial function and vascular occlusions, caused by microspheres, with decline of renal parenchyma particularly of the tubules. CONCLUSION: Multiple sequential intracoronary microembolization can effectively induce myocardial dysfunction with histological signs of chronic ischemic cardiomyopathy and pathological changes of lung, liver and kidney, which can directly be coursed by chronic heart failure. Thus, the present model may be suitable in experimental work on heart failure and LV assist devices, e.g. for studying the impact of mechanical unloading, mechanisms of recovery and reverse remodeling.
Abstract: Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. Indirect evidence from clinical trials demonstrates that chronic inhibition of the renin-angiotensin-system (RAS) significantly reduces the incidence of AF. Since mechanisms of this protective effect of RAS-blockade are poorly understood, we directly tested proarrhythmic effects of angiotensin II (Ang II) in human atrial myocardium. METHODS: Isolated trabeculae from human atrial appendages (n=80) were electrically stimulated. We assessed isometric force and incidence of arrhythmic extra contractions (AECs) with and without increasing concentrations of Ang II (1-1000 nmol/L) in the absence or presence of receptor-blockade by saralasin (non-specific ATR-antagonist), irbesartan (AT1R-antagonist) or PD123319 (AT2R-antagonist). RESULTS: Twitch force and AECs concentration-dependently increased with Ang II. Effects became significant at concentrations >1 nmol/L Ang II and were maximal at 1000 nmol/L (increase in twitch force to 157+/-14% and AECs from 0 to 80%) saralasin and irbesartan partially prevented the inotropic effect of 100 nmol/L Ang II (by 45+/-12% and 68+/-6%; p<0.05), and completely prevented the occurrence of AECs. CONCLUSION: Ang II exerts direct pro-arrhythmic effects in human atrial myocardium. These effects are mediated by AT1-receptors and can be prevented by AT1R-blockade. This mechanism may contribute to the beneficial effects of RAS-blockade on AF in clinical trials.
Abstract: OBJECTIVE: Endothelin is the most potent endogenous vasoconstrictor and is involved in several vascular disorders such as arterial hypertension. Its intense interaction with other vasoactive hormone systems revealed the consideration about the endothelin gene as an interesting candidate for influencing the development of essential hypertension and hypertensive endorgan damage. The purpose of this study was to investigate the role of endothelin-1 Lys198Asn polymorphism in patients with severe arterial hypertension as well as associated endorgan damages. METHODS: In 400 hypertensive patients and 150 normotensive controls we examined the endothelin-1 Lys198Asn polymorphism by DNA sequencing and patients were divided according to their genotype (GG, GT, and TT). Moreover, the frequency of endothelin-1 Lys198Asn polymorphism was investigated with respect to the prevalence of several actual or historical endorgan damages (renal disorder, coronary artery disease, vascular events, vascular damage, and congestive heart failure) in hypertensive patients. RESULTS: Genotype distribution for endothelin-1 Lys198Asn polymorphism was 57.3% (GG), 41.3% (GT), and 1.43% (TT) in normotensive individuals; and in hypertensive individuals was 54.75% (GG), 43% (GT) and 2.25% (TT). Genotype distribution was unaffected in patients with severe hypertension, renal disorder, vascular events, vascular damage, and congestive heart failure. We, however, found a significant difference in hypertensive individuals with coronary artery disease and TT genotype (P=0.004). CONCLUSION: Homozygous TT carrier contributes to a higher prevalence of coronary artery disease, especially for three-vessel disease in hypertensive individuals. Thus, the polymorphism at position 198 could serve as a possibility to differentiate high-risk subgroups in the heterogeneous population of hypertensive patients.
Abstract: After a fulfilled life, Norman E. Shumway, the great pioneer of cardiac transplantation, died of lung cancer 1 day after his 83rd birthday in Palo Alto, California, USA. Already at the beginning of the 1960s, he and his colleague Richard R. Lower did revolutionary experimental work on developing and establishing the technique of orthotopic cardiac transplantation in dogs. Several studies on cardiac transplantation were carried out in his department and a few years later, Shumway and his team were on their way to perform the worldwide first human-to-human cardiac transplantation. On December 3, 1967, Christiaan Neethling Barnard, a cardiac surgeon from South Africa, forestalled Shumway and performed this operation in Cape Town, South Africa. This event initiated a global boom of cardiac transplantations in the following years." Many heart centers started their own cardiac transplant programs but high mortality rates led again to stagnancy of transplant activities. Shumway remained stable in believing in good results of cardiac transplantation and continued his program steadily. At the beginning of the 1970s, he and his group were responsible for most cardiac transplantations worldwide.
Abstract: AIM: The angiotensin I-converting enzyme insertion/ deletion polymorphism (ACE-I/D), including three genotypes (II, ID, DD), with a known impact on midterm mortality and morbidity in patients after coronary artery bypass graft surgery (CABG), was studied. Since this polymorphism has been linked with increased vascular response to phenylephrine during cardiopulmonary bypass (CPB), we investigated its possible effect on perioperative hemodynamics in patients undergoing CABG. METHODS: Genotyping for the ACE-I/D was performed by polymerase chain reaction (PRC) amplification in 110 patients who underwent elective CABG with CPB. Patients were assigned to two groups according to their genotype (group II [II genotype] and group ID/DD [ID and DD genotypes]). Systemic hemodynamics were measured directly before and at 4 h, 9 h, and 19 h after CPB. RESULTS: Genotype distribution of ACE-I/D was 18%, 57%, and 25% in genotypes II, ID, and DD, respectively. The two groups were similar in age (group II: 66+/-6 years, group ID/DD: 66+/-8 years), body-mass-index (BMI) (group II: 28+/-2, group ID/DD: 29+/-5 kg/m2), male: female ratio (group II: 16: 4, group ID/DD: 63: 27) and Euroscore (group II: 3.1+/-1.9, group ID/DD: 3.5+/-2.1). There were no differences in mortality rate or perioperative systemic hemodynamics. The pulmonary vascular resistance before cardiopulmonary bypass was higher in the ID/DD genotypes than in the II genotypes (227+/-121 vs 297+/-169 dyn.s(-1).m2.cm(-5)). Four hours after CPB no difference remained; at 9 h after cardiopulmonary bypass there was a slight difference in pulmonary vascular resistance between the two groups (247+/-134 vs 290+/-117 dyn.s(-1).m2.cm(-5)) and a significant difference in pulmonary arterial pressure (19+/-6 vs 23+/-8); at 19 h after CPB the differences were no longer detectable. CONCLUSION: ACE-I/D had no influence on perioperative systemic hemodynamics. However, transitory differences in pulmonary hemodynamic were observed after CPB. These differences may have been due to changes in serum ACE activity during CPB.
Abstract: A case is presented of spontaneous return of circulation after cardiac arrest in a patient with a pacemaker without intraoperative resuscitation. In the literature this kind of situation is called the Lazarus phenomenon. Cardiac arrest of the patient occurred during surgery and because of the poor prognosis no cardiopulmonary resuscitation was initiated. After 6 min of apnoea and cessation of circulation, the circulation restarted spontaneously and surgery was continued. Afterwards the patient was transferred to the intensive care unit but died 2 days later without regaining consciousness. The pathophysiological mechanisms for the Lazarus phenomenon are poorly understood but several mechanisms and multifactorial events are discussed in the literature.
Abstract: INTRODUCTION: In the presented retrospective study, we report on our results with partial resection of infected prosthetic grafts after aorto-bifemoral graft placement in eight male and three female patients. METHODS: In all 11 patients clinical signs of infection were observed and bacteriological cultures were positive. Three patients underwent immediate surgery for perforation of an aneurysm at the distal anastomosis, eight patients underwent elective surgery. In all cases silver-coated Dacron prostheses were implanted. Assessment of outcome was based on survival, limb salvage, persistent or recurrent infection, and prosthetic graft patency. RESULTS: In two cases, a partial wound dehiscence occurred which was treated with ambulant Vacuseal dressings for 16 and 21 days until secondary wound healing was achieved. In eight patients systemic markers of inflammation completed normalised within nine days. Follow-up CT-scans failed to demonstrate any signs of recurrent infection or peri-graft fluid collections. Patients were treated with specific antibiotic therapy for no more than three months. Post-operative bacteriological cultures were negative in all patients. The mean follow-up was 2.5+/-0.5 yrs. During follow-up, none of the patients died and there were no amputations. CONCLUSION: Despite only partial resection of the infected prostheses, the reported surgical procedure offers good results. This approach maybe particularly suitable for the treatment of elderly patients with prosthesis infections.
Abstract: BACKGROUND: Cardiopulmonary bypass (CPB)-related inflammatory response can be attenuated by glucocorticoid treatment, but its impact on postoperative cardiopulmonary function remains controversial. It was investigated whether the systemic and myocardial antiinflammatory effects of glucocorticoids are associated with improved cardiopulmonary function in cardiac surgery patients. METHODS: Eighty patients undergoing elective coronary artery bypass grafting were randomly assigned to receive a single shot of methylprednisolone (15 mg/kg) or placebo before CPB. Variables of myocardial and pulmonary function and systemic hemodynamics were measured before and 1, 4, 10, and 24 hours after CPB. Blood was sampled for measurement of proinflammatory (tumor necrosis factor-alpha, interleukin 6, interleukin 8) and antiinflammatory (interleukin 10) cytokines (by enzyme-linked immunoassay), troponin T, and C-reactive protein. Phosphorylation of inhibitory kappa-B alpha and p38 mitogen-activated protein kinase was determined in right atrial biopsies before and after CPB (phosphoprotein assay). RESULTS: Preoperative and intraoperative characteristics of patients were not different between groups. Methylprednisolone attenuated postoperative tumor necrosis factor-alpha, interleukin 6, interleukin 8, and C-reactive protein levels while increasing interleukin 10 release. Myocardial inhibitory kappa-B alpha was preserved with methylprednisolone (p < 0.05 versus placebo), but p38 mitogen-activated protein kinase activation occurred in both groups after CPB (p < 0.05 versus before CPB). Methylprednisolone improved postoperative cardiac index and was associated with decreased troponin T when compared with placebo (p < 0.05). Postoperative blood glucose, oxygen delivery index, and pulmonary shunt flow were increased in the methylprednisolone group (p < 0.05). There was no difference in postoperative oxygenation index, ventilation time, and clinical outcome between treatment groups. CONCLUSIONS: Glucocorticoid treatment before CPB attenuates perioperative release of systemic and myocardial inflammatory mediators and improves myocardial function, suggesting potential cardioprotective effects in patients undergoing cardiac surgery.
Abstract: Josef Koncz (1916-1988) was until given emeritus status in 1982 director of the Department of Cardiothoracic and Vascular Surgery, which was specifically founded for him in Goettingen, Germany. By the fusion of three different surgical branches the University hospital of Goettingen took over the role of a pacemaker and initiated a standard in the development of this new specialty in Germany. The scientific and clinical work done by the Department of Cardiothoracic and Vascular Surgery was shaped by the personality of the surgeon and scientist Josef Koncz. He was a successful surgeon and innovative pioneer in one person. Already in 1956, he started open-heart surgery and proceeded this technique in an impressing series. In 1965 he was the first in Germany who operated upon the transposition of the great vessels by Mustard's method and developed together with his long-standing assistant, Huschang Rastan, an operation technique to extend the left-ventricular outflow tract combined with tunnel-shaped subvalvular aortic valve stenosis. Another essential element of his work is related to the establishment of the Cardiothoracic and Vascular Surgery as an independent specialty, ending in the foundation of the German Society for Thoracic and Cardiovascular Surgery in 1971.
Abstract: Aneurysms of the great venous vessels represent anatomical rarities. Most malformations of the venous system published so far concern mainly the inferior vena cava and arise in different formations. Reports of malformations of the renal veins are limited to a few case reports and may lead to diagnostic and therapeutic difficulties. We report on an case of a asymptomatic, aneurysmatic venous malformation of the vena cava inferior With consideration of the entire findings we preferred a conservative treatment of the patient.
Abstract: BACKGROUND: Differences in vascular reactivity have been associated with variable NO release due to 894G/T and -786C/T polymorphisms of the eNOS gene. Carriers of the 894T and -786C alleles are known to have enhanced vascular responsiveness to vasoconstrictor stimulation due to decreased NO generation. Thus, we hypothesized that eNOS gene polymorphism could influence perioperative hemodynamics and catecholamine support in patients undergoing cardiac surgery with CPB. METHODS: In 105 patients undergoing elective CABG with CPB, systemic hemodynamics, cardiac index (CI), systemic and pulmonary vascular resistance indices (SVRI, PVRI) and catecholamine support were measured at baseline and 1 h, 4 h, 10 h and 24 h after CPB. Genotyping for the 894G/T and -786C/T eNOS gene polymorphisms was performed by polymerase chain reaction amplification. Patients were divided according to their genotype (894G/T: GG=group 1, GT and TT=group 2; -786C/T: TT=group 3, CT and CC=group 4). RESULTS: Genotype distribution for 894G/T polymorphism was 41% (GG), 52.4% (GT), 6.6% (TT) and for -786C/T polymorphism 37.1% (TT), 41.9% (CT) and 21% (CC). Pre- and intraoperative characteristics and systemic hemodynamics did not differ between groups. CI, SVRI and PVRI remained unaffected by genotype distribution. Statistical analysis of postoperative data revealed no difference between groups, especially for pharmacologic inotropic or vasopressor support. Also, coexistence of the 894T and -786C alleles had no impact on perioperative variables compared to homozygous 894G and -786T allele carriers. CONCLUSIONS: In contrast to current suggestions, the 894G/T and -786C/T genetic polymorphisms of the eNOS gene do not influence early perioperative hemodynamics after cardiac surgery with CPB.
Abstract: INTRODUCTION: In addition to their lipid-lowering action, it has been demonstrated that statins can exert direct anti-inflammatory effects. We investigated the effect of preoperative statin therapy on systemic inflammatory markers and myocardial NF-kappaB inhibitor IkappaB-alpha after cardiac surgery. METHODS: Thirty-six patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass (CPB) with cardioplegia were divided into two groups (statin group, n = 18; control group, n = 18). Plasma concentrations of pro-inflammatory cytokines (tumor necrosis factor alpha [TNFalpha], interleukin [IL]-6, IL-8) and anti-inflammatory IL-10 were measured before and 1, 4, 10, and 24 hours (h) after CPB. Phosphorylated IkappaB-alpha/total IkappaB-alpha ratio was assessed before and after CPB in right atrial biopsies. RESULTS: Baseline and operative data did not differ between groups. Statin therapy was associated with lower preoperative low-density lipoprotein levels compared to control (73+/-6 vs. 92+/-6 mg/dL; P=0.03). Release of IL-6 was attenuated in the statin group at 4 h (2270+/-599 vs. 5120+/-656 pg/ml; P<0.01) and 10 h (1295+/-445 vs. 3116+/-487 pg/ml; P<0.05) compared to the control group. IL-10 increased after surgery in both groups (P<0.05), but was higher in the statin group at 1 h (66+/-15 vs. 26+/-16 pg/mL; P<0.01). Phosphorylated IkappaB-alpha/total IkappaB-alpha ratio before CPB did not differ between groups, but was elevated after CPB in both groups (P<0.05), indicating enhanced degradation of IkappaB-alpha. Statin therapy had no effect on TNFalpha and IL-8. CONCLUSIONS: Preoperative statin therapy attenuates the release of pro-inflammatory IL-6 and up-regulates anti-inflammatory IL-10 after cardiac surgery with cardioplegia, but fails to inhibit phosphorylation of myocardial IkappaB-alpha.
Abstract: BACKGROUND: Surgical correction of hypertrophic obstructive cardiomyopathy in severely symptomatic patients has been proven to be effective over the long term. The introduction of catheter-based procedures restricts surgical therapy to a subset of patients not suitable for septal ablation or requiring concomitant cardiac surgery. METHODS: Between 8/2001 and 8/2003, 25 patients (58 +/- 15 years) underwent extended transaortic septal myectomy with partial excision and mobilization of the papillary muscles. Concomitant surgical procedures were performed in 40 % (CABG n = 9, aortic valve replacement n = 2). In 24 %, prior septal ablation was ineffective. Intraventricular gradient was 80 +/- 29 mm Hg at rest and 143 +/- 35 mm Hg during exercise. Mitral regurgitation affected 72 % of patients, and 88 % were NYHA functional class III or IV. RESULTS: No hospital death, no postsurgical ventricular septal defect, and no complete atrioventricular block occurred. Severe nonfatal complications occurred in 24 % of patients. Intensive care was necessary for 1.8 +/- 1.7 days; total hospital stay was 11.8 +/- 3.8 days. Early follow-up was complete in 100 % (15 +/- 6 months, total of 376 months) with no late deaths, no relevant mitral regurgitation, or intraventricular gradients. Functional status was markedly improved (NYHA class I 40 %, class II 56 %, class III 4 %). CONCLUSIONS: Early results of extended surgical myectomy and reconstruction of the subvalvular mitral apparatus in hypertrophic obstructive cardiomyopathy remain excellent with respect to mortality, morbidity, and functional capacity even when restricting surgery to patients earlier supposed to be at high risk.
Abstract: OBJECTIVES: We have previously demonstrated experimentally an amelioration of reperfusion injury of the lung after preservation using low potassium dextran (LPD) solution compared to Euro-Collins (EC) solution. Now we report on early graft function in 106 lung transplant recipients of LPD or EC preserved grafts. METHODS: Initial graft function was assessed by measurement of lung compliance and oxygenation index 2 h after transplantation. Length of stay on the intensive care unit and hours of mechanical ventilation were compared. Correlation of donor oxygenation, ischemic time, type of transplant, recipient age and sex as well as initial lung compliance and oxygenation with early postoperative course were calculated. RESULTS: Dynamic lung compliance was significantly (P<0.05) improved in the LPD group. PO(2)/fiO(2) was comparable in both groups (303+/-122 mmHg LPD, 282+/-118 mmHg EC). Mechanical ventilation was used for 321+/-500 h in the EC group and 189+/-365 h in the LPD group (P=0.006). Intensive care therapy was required for 17.2+/-23.7 days in the EC group and 10.4+/-16 days in the LPD group (P=0.012). Significantly higher lung function parameters were obtained in extubated recipients of LPD preserved grafts 2 weeks after TX. Thirty day graft survival was improved in the LPD group (P=0.045). In the EC group, 30 day mortality was 14.2 and 8% in the LPD group. CONCLUSIONS: A reduction of perioperative mortality and morbidity suggests that LPD solution has superior early graft function compared to lung preservation using EC solution.
