Abstract: This report is to investigate the correlation between common carotid blood flow (CCBF) properties and the risk factors for cardiovascular disease. The measurement system was designed for simultaneously monitoring of CCBF and electrocardiogram (ECG) in order to get more valid information for detection and diagnosis of cardiovascular disease. In our study, blood flow velocimeter was developed to measure blood flow in carotid by using ultrasound Doppler technique. This measurement system is based on a continuous-wave (CW) Doppler ultrasound method with two semicircular piezoelectric (PZT) transducers, one continuously transmitting ultrasound, and the other continuously receiving the echoes. Eleven patients with cardiovascular disease underwent in the experiment. In the report, blood flow was compared with data from 25 healthy subjects which asymptomatic subjects putatively free of cardiovascular disease as controls. The maximum of CCBF velocity was 102.8 (SD 18.3) cm/s in the 25 healthy subjects. While, the maximum of CCBF velocities were 53.9 (SD 16.6) cm/s in the eleven cardiac patients. The data suggest that CCBF velocity decreased significantly in the cardiac patients and by simultaneously monitoring of CCBF and ECG were probably obtained more valid information to detect and diagnose cardiovascular disease at the early stage.
Abstract: Our purpose of the study is to measure the blood flow in the carotid artery during physical exercises. We have developed the blood flow velocimeter during physical exercises by using the non-invasive Doppler ultrasound method. We used it and measured blood flow in the carotid artery in which using a cycle ergometer and had two exercise tests in this report. The protocol exercise with transient response and ramp response were conducted. As a result, maximum blood flow velocities changed largely during physical exercises. In particular the maximum blood flow velocity was decreased during physical exercise in transient response. In addition, we could also detect arrhythmia that occurred in the subject immediately after exercise. For this reason, blood flow measurement during physical exercise maybe useful for the early detection of cardiovascular disease. Recently, the physical exercises are very popular for health maintenance.
