Primary Study Of Carotid Atherosclerosis Plaque Biomechnics Using Ultrasonic Velocity Vector Imaging In Patients With Coronary Coronary Artery Disease

BackgroundCoronary heart disease (CHD) is common and multi-onset disease, which has serious effects on the health of human beings, and their pathological basis is atherosclerosis(AS). Traditionary, the development of AS was thought to be a line procedure, during which lipid infiltrated into the intima of the main therapy strategy, However, recent studies show that plaque disruption and arterial thrombosis are recognized as critical to the onset of acute coronary syndrome(ACS) and a vulnerable that is prone to rupture is vital to induce ACS. Therefore, it is very important to detect early atherosclerosis and vulnerable plaques for angiocardiopathy. In recent years, velocity vector imaging has already been thought as the most important echocardiographic technology to evaluate the velocity strain and strain rate of regional cardial function but whether or not velocity vector imaging evaluate stability of atherosclerosis plaque hasn't been proved. There are many problems to be resolved:(l) How do the velocity strain and strain rate change on the corresponding vascular of plaque and that without plaque?How dose the velocity strain and strain rate on the corresponding normal and abnormal artery change?(2) How dose the cap and shoulder of plaque affect the velocity strain rate and strain rate gradient between the cap and the shoulder? how do the velocity ,strain and strain rate change?(3)Are there any different of the velocity ,strain and strain rate between the hard plaque soft plaque? (4) Among the quantitative parameters, which is the most sensitive parameter in assessing the severity of atherosclerosis function? The above problems constitute the objective of this topic.Aims1. To assess how the velocity strain and strain rate changes on the corresponding vascular of plaque and without plaque? How do the velocity, strain and strain rate on the corresponding normal and abnormal artery change?2. To explore how the cupular part of fiber cowl and shoulder of plaque affect the velocity ,strain and strain rate between the cupular part of fiber cowl and the shoulder of plaque?3. To evaluate is the velocity strain rate and strain rate of the corresponding hard plaque and soft plaque their change different?Methods1. Study populationFrom March 2007 to Jone 2007, 86 patients (61 male;25 female, mean age (53.2±8.8) years)with CAD according to the results of coronary arteriography (CAG) in Qilu Hospital were enrolled in this study. Among the patients, the acute myocardial infraction attacked 16 patients, old myocardial infraction invaded 10 patients 27 patients suffered from unstability angina and 33patients suffered from stability angina. All the subjects were in sinus rhythm and with NYHA grades I -III cardial function. Normal control 50(61male;25female. mean age (46.2±6.8) years).2. Echocardiographic Image Acquisition(1) All VVI echocardigraphy examinations were performed on ACUSO Sequoia ultrasound machine with a 15L8w-s transducer(8.0MHZ). Resting two-dimensional gray-scale echocardiography and VVI were obtained from the long axis views with each subject in recumbent position and limb leads ECG monitored. Each cine-loop included at least 3 cardiac cycles. All echocardiography were stored digitally on magnetic optical disk in raw data mode for later offline analysis. (2) Echocardiography images were acquired using PHILIPS SONOS 7500 ultrasound scanner with a S₄ transducer(2.0 to 4.0MHZ) .All echocardiography were stored digitally on magnetic optical disk in raw data mode for later offline analysis.3. Data processing and Measurements(1)I collected patients' history, had them take EKG examnation and determined serum parameter by 7107A at the same time intima-media thickness, AIIc% and endothelium function were determined by ultrasound examination. Using velocity vector imaging traced carotid (VVI).(2) Velocity strain and strain rate data measurementsA dedicated velocity vector imaging(VVI) workstation was employed for the off-line 2D gray-scale image analysis and the exploration of mechanical parameters (i.e., peak velocity strain and strain rate)changes at the intima of plaque and without plaque and the intima of the cap and shoulder of plaque on the corresponding carotid. The mechanical parameters at different points of carotid intima were measured simultaneously and calculated automatically which were used for statistic analysis.4 .Statistic analysis:Continuous variables were reportes as mean±deciazione standard and had been analysed by SPSS 13.0. For all analysis, a p value less than 0.05was considered significant.Results1. The level of IMT in coronary heart disease patients was higher than that in normal control (P<0.05). While the level of AIIc% in soft plaque was lower than that in hard plaque.2. The systolic maximum velocity of carotid with normal contract was higher significantly than carotid which has no plaque with coronary heart disease (p<0.05).3. The maximum strain rate of fabric cowl in carotid atherosclerosis plaque was lower significantly than that of plaque shoulder (p<0.05).4. The systolic maximum velocity of soft plaque in carotid atherosclerosis was lower significantly than that of hard plaque (p<0.05).5.There was negative correlation between the maximum strain rate of fabric cowl in carotid atherosclerosis plaque and the level of AIIc% in soft plaque negativelyConclusions1. The systolic maximum velocity of carotid with normal contract was higher significantly than carotid which has no plaque with coronary heart disease.2.The maximum strain rate of fabric cowl in carotid atherosclerosis plaque was lower significantly than that of shoulder.3.The maximum strain rate of fabric cowl in carotid atherosclerosis plaque was more sensitive significantly than optical densitometry .