Objective To explore the application of acoustic densitometry(AD) on evaluating effects of simvastatin, probucol, captopril and Chinese medicine on the atherosclerosis (AS) characterization of rabbit. Methods Sixty male New Zealand rabbits were divided randomly into five groups:normal group, regression control group(RC), simvastatin group, probucol group, captopril and Chinese medicine group. The intima-media thickness (IMT), lumen acoustic densitometry (AII-L), intima-media acoustic densitometry (AII-I), adventitia acoustic densitometry (AII-A) and corrected acoustic densitometry (AIIc) of abdominal aorta were measured with high frequency ultrasound at the beginning, the 12th and 24th week of the experiment. Abdominal aorta was also examined through pathology at 24th week of the experiment. Results Analysis of abdominal aortas from 8 rabbits in vitro showed the different effects of the different frequencies of transducer on the AII value of lumen, intima-media and the adventitia. AIIc was calculated to evaluate acoustic density of intima-media to avoid the influence of individual divergence.AIIc in 4 drug-therapy groups were significantly higher than AS model group (P

Objective To explore the feasibility of ultrasonic examination in the strain(S) and strain rate(SR) of carotid artery atheromatous plaque, and the distribution of S and SR of the atherosclerotic plaques. Methods Tissue velocity imaging(TVI) was used in 26 cases of coronary artery disease(CAD),and 35 atherosclerotic plaques in the carotid artery were found.The peak values of displacement, S and SR in different plaque sites were obtained with Q-analysis software. The estimation of S and SR of same sites was acquired in different parametric settings, including S length, S reject and S scale. Results Different parametric settings had no influence upon the estimation of S and SR. However, significant difference of S and SR could be found in different plaque sites, such as the shoulder, the surface of fibrous cap and the base and it was the same case among different acoustic plaque types. S and SR distribution patterns were similar between angina pectoris group and old myocardial infarction group; yet they were significantly different between acute myocardial infarction group and the former two groups. Conclusions TVI technique and ultrasonic Doppler-based strain imaging method could be used in carotid arteries. Strain concentrated mainly on the surface of fibrous cap and the plaque shoulder. SR of plaque shoulder among three acoustic plaque types was different. From the surface to the base axially, S and SR decreased gradually.

Objective To evaluate the ventricula r septal defect qualitatively and quantitatively by real-time three-dimensional echocardiography (RT-3DE).Methods RT-3DE were performed in 10 pig hearts with 22 ventricular septal defects in multiple orientations and cross sections. The diameters and areas of ventricular septal defects were measured both in RT-3DE and anatomic view. Echo images and parameters derived by RT-3DE were compared with anatomic view. Results Technically satisfactory RT-3DE images were obtained in all preparations. The location, size, morphology, and spatial relationships with surrounding cardiac structure of ventricular septal defects were displayed instantly. No significant differences were found between RT-3DE and anatomic measurements. Conclusions RT-3DE has advantages of instantly displaying the ventricular septal defects in anyplane and has important surgical and interventional implications.

0.05 ), while defect dimensions by 2-D E were lower than those in surgical operation(P

Objective To explore the methodology of sca nning, cutting and measuring normal cardiovascular structures by real-time three-dimensional echocardiography (RT-3DE) and it's clinical applications. Methods Conventional two-dimensional echocardiography (2-DE), RT-3DE and full volume three-dimensional echocardiography (FV-3DE)were performed in 20 normal volunteers to visualize normal cardiovascular structures in multiple orientations and cross sections both in static and dynamic fashions, and all echo images derived by three techniques were compared and analyzed.Results Technically satisfactory 2-DE, RT-3DE and FV-3DE images were obtained in all subjects. Compared with conventional 2-DE technique, RT-3DE has the advantages of instantly displaying three orthogonal planes and spatial relationships of any cardiac structure within a "piece of cake" images of a regional heart, while FV-3DE has the superiority in rapidly depicting three orthogonal planes and spatial relationships of any cardiac structure within a pyramid images of a whole heart. Conclusions Both RT-3DE and FV-3DE techniques can display cardiac structures unobtainable by 2-DE and are useful in reducing the subjectivity and blindness of 2-DE studies, which may enhance the diagnostic accuracy and work efficiency of echo laboratories and produce important clinical values.

0.25-).Total cholesterol showed negative correlatioin with diameter changes responsing to Ach(r= -0.57-,P

Objective To study histological characteristics of atherosclerotic plaque in carotid and femoral arteries with acoustic densitometry (AD) technique.Methods The carotid and femoral arteries were examined in 65 patients by ultrasound AD technique with average image intensity ratio (AIIr) as the statistical index.Results The AIIr values of intima correlated well with the arterial stiffness ?(r= 0.75 ,P

0.05 ).However,there were more eccentric plaques in ruptured than in non-ruptured groups ( P

Objective To explore the value of intravascular ultrasound (IVUS) in diagnosing plaque disruption and arterial thrombosis.Methods Balloon-induced arterial wall injury and then feeding on a diet of 1% cholesterol for 8 weeks, 17 New Zealand white rabbits were established as atherosis(AS) models.At the end of the eighth week, the resulting plaques were incubated transluminally with recombinant adenovirus carrying a p53 transgene. After two weeks, the rabbits underwent pharmacological triggering with Russell viper venom(RVV) and histamine. IVUS was used before and after the rabbits were triggered pharmacologically. The value of IVUS in diagnosing plaque disruption and arterial thrombosis was derived by comparing the results of IVUS with pathologic findings. Results IVUS found that plaques disruption and thrombosis occurred in 12 of the 14 rabbits, totally 18 thrombi. A histologically confirmed plaque disruption and intraluminal thrombus were visualized in 12 of the 14 rabbits, totally 20 thrombi. By comparing the results of IVUS with histopathology, the true positive rate was 85% and false negative rate was 15%, the sensitivity and specificity of IVUS were respectively 85% and 67%. IVUS data correlated well with the histopathology regarding thrombus length(r=(0.73),P(0.05)). Conclusions IVUS can detect plaque disruption and arterial thrombosis.

Objective To explore the practicability of real-time myocardial contrast echocardiography (MCE) in assessing the transmural distribution of myocardial perfusion. Methods Three grades of left anterior descending coronary artery(LAD) stenoses were created in 6 open-chest dogs. Stenoses reduced LAD flow by 50%, 75% and 90% of hyperemia guided by flow probe. Low-energy MCE were performed at baseline, hyperemia reduced by dipyridamole, three different stenoses, reperfusion and complete occlusion, respectively, during continuously infusion of SonoVue. Regions of interest(ROI) were placed individually within endocardial and epicardial layers and myocardial signal intensity-versus-time plots just after high-energy FLASH frames were fitted to an exponential function to obtain values of A, ?, A??. The corresponding transmural gradients, defined as endocardial-epicardial ratios of A (A-EER),?(?-EER) and A??(A??-EER) were also calculated. Results The transmural distributions of A,? and A?? were more or less homogeneous at baseline,hyperemia and 50% reduced LAD flow, with their transmural gradients near 1. When LAD flow was reduced by 75%,? and A?? from endocardial layer decreased (P