猪腹主动脉下端狭窄对邻近上游血流动力学的影响

目的 探讨外周动脉流速曲线中几个波峰的形成机制.方法 幼年家猪6只,制作束缚肢体及肾上腺素实验模型,观察对应髂外动脉流速曲线波形的演变,测量收缩期峰值速度、收缩期后最小速度、舒张期峰值速度、舒张期末速度.结果 随下游循环阻力增加,收缩期波形倾向于陡直而尖锐;收缩期后最小速度逐渐减低达到零,而后负向增加;舒张期波幅减低,舒张期末速度逐渐减低达到零.血管收缩力增强时,这些变化更显著.结论 心脏射血形成收缩期主波,收缩期后反向波是下游血管弹性同缩引起血液反流形成的,舒张期正向波是上游血管弹性回缩引起血液短暂加速形成的,外周循环阻力对舒张期波形影响显著,收缩期后反向波的出现反映下游循环阻力明昆增高.

Influence of abdominal aorta extremity stenusis on proximal upstream artery haemodynamics in swines

Objective To study the formations of several ridges in peripheral artery velocity tracing. Methods The experimental models of constrainting limb and adrenaline were performed in 6 juvenile susscrota domesticas,tbe variations of the external lilac artery velocity tracing observed,and the parameters of peak systolic velocity (PSV), minimum post-systolic velocity (MPV), peak diastolic velocity(PDV) and end diastolic velocity(EDV) were obtained. Results With the increase of downstream circulation resistance, systolic waveshape inclined to acumination, MPV gradually degraded to zero and negatively increased subsequently, diastolic wave amplitude lowered, and EDV gradually decreased to zero. The stronger vasoconstriction was, the more striking the variations were. Conclusions Cardiac ejection forms systolic dominant wave, post-systolic backward ware is the result of backstreaming because of elastic recoil of downstream artery,and diastolic forward ware is the result of blood transient acceleration caused by elastic recoil of upstream artery. Systemic vascular resistance has significant effect on diastolic waveshape,and the occurrence of post-systolic backward ware implies downstream circulation resistance obviously increases.