运动负荷超声试验对无症状心肌缺血心功能的评价

利用次极量卧位蹬车运动负荷超声试验研究无症状心肌缺血（SMI）患者和心绞痛（AP）患者在心肌缺血发作过程中左心功能的改变。15例SMI患者和12例AP患者在运动负荷超声试验中都出现心肌缺血，14例冠造正常者为对照组。结果：（1）AP组、SMI组和对照组的运动总时间和运动总功量依次增加，三组之间比较差异均有显著性（P＜0．05）。（2）对照组：在运动中，每例患者的收缩功能各项指标都明显升高，LVEF上升大于5％；二尖瓣血流峰值E峰和A峰也明显升高，而E／A比值下降。（3）SMI组：总体收缩功能各项指标在运动早期也呈上升趋势，LVEF上升大于5％，而随运动量进一步增加，收缩功能不再增强；二尖瓣血流峰值E4和A4也升高，但E／A比值变化不明显。（4）AP组：在运动中，心脏收缩功能各项指标基本保持不变，LVEF上升小于5％；二尖瓣血流峰值E峰上升明显，A峰轻微上升，E／A比值明显增加。结论：（1）正常人的左室收缩功能和舒张功能随着运动量的增加而增强。（2）在相同负荷条件下或相同程度的心肌缺血发作过程中，SMI患者左室功能受损程度轻于AP患者。

Evaluation or left ventricular function in patients with silent myocardial ischemia by exercise echocardiography

To evaluate left ventricular function in patients with silent myocardial ischemia (SMI) and angina pectoris (AP) by submaximal supine exercise echocardiography. Methods: Exercise echocardio graphy and coronary angiography were performed in 15 patients with SMI and 12 patients with AP,who had Coronary Artery Disease and positive exercise stress test, and 14 petients were normal Rerelts: (1 )The total exercise duration and exercise work load increased seriatim among the patients with AP and SMI and healthy controls (HC).(2) With the increasing of exercise work load,LVEF and AoVmax in SMI and HC increased. LVEF raised by 5%. When exercise work load continued to increase, LVEF and AoVmax elevated again in HClbut LVEF didn' change any more in SMI and in AP group (3) Amax and Emax increased significantly and E/A ratio didn't change in SMI,Emax increased obviously and Amax increased slightly and E/A ratio enhanced (P<0.05) in AP,Amax and Etnax increased and E/A ratio decreased significantly (P<0. 05) in HC' Conclusions: (1) With the increasing of exercise work load,left ventricular systolic function and diastolic function enhanced in HC. (2) In the same exercise work load left ventricular dysfunction in SMI was slighter than that in AP.