多普勒超声对兔动脉硬化的血流动力学与流变学研究

目的通过研究兔颈总动脉粥样硬化血液流变学与动力学的变化规律,探求其早期诊断的敏感指标.方法选24只大耳白兔随机分成2组:A组为正常饲料组(6只),B组为高脂饲料喂养组(18只),各分成3个亚组,分别喂养4周、8周、12周.观察颈总动脉Vs、PI、RI及血液流变学特性的变化,用病理结果进行验证.结果在兔AS不同阶段,B组家兔颈总动脉PI、RI逐渐增高(P＜0.01或P＜0.05),Vs无显著变化;血液流变学指标中全血黏度、红细胞聚集指数在4周以后出现进行性增高(P＜0.01或P＜0.05),并与PI、RI呈正相关;红细胞变形指数逐渐降低(P＜0.01或P＜0.05),与PI、RI呈负相关.结论血流动力学与血液流变学变化相结合可以早期定性、定量检测AS,动态观察其病变进展情况.

Study of hemodynamics and hemorheology in rabbits with atherosclerosis by Doppler ultrasound

Objective To find a sensitive indexes in the early diagnosis of atherosclerosis in rabbits by studying hemorheological and hemodynamic changes. Methods Twenty-four white big-ear rabbits were divided into two groups randomly: group A (6 rabbits) was fed with normal rabbit chow, while group B (18 rabbits) was fed with high cholesterol diet. Then each group was divided into three subgroups which were fed for 4 weeks, 8 weeks and 12 weeks respectively. The changes in systolic peak velocity (Vs), pulsatility index (PI), resistence index (RI) and hemorheological characteristics of common carotid artery were observed, and verified by histological examination. Results At different stages of AS, the values of PI and RI of common carotid artery increased gradually in group B (P<0.01 or P<0.05), while Vs had no significant changes. From the 4th week, the hemorheological indexes of blood viscosity and RBC aggregation index increased gradually(P<0.01 or P<0.05), and showed positive correlation with PI and RI. RBC deformation index reduced gradually (P<0.01 or P< 0.05 ), and showed negative correlation with PI and RI. Conclusion The changes of hemodynamics and hemorheology can assess early atherosclerosis qualitatively and quantitatively, and monitor its progression.