急性缺血时犬3层心肌单向动作电位时程和有效不应期变化  

Changes of monophasic action potential duration and effective refractory period of three layers myocardium of canine during acute ischemia in vivo

作　　者：吕家高[1] 张繁之[1] 王琳[1] 卜军[1] 王岚[1] 陈柏迪[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院心内科,武汉430030

出　　处：《临床心血管病杂志》2005年第11期660-662,共3页Journal of Clinical Cardiology

摘　　要：目的:探讨急性缺血对犬在体3层心肌的电生理影响。方法:将12只犬随机分为急性缺血组(6只)和假手术组(6只)。应用单向动作电位(MAP)技术和特制的复合电极同步记录MAP和测定有效不应期(ERP),并分析跨室壁复极离散(TDR)和跨室壁不应期离散(TDE)。结果:在急性缺血组,MAP时程从[(201·67±21·42)ms缩短至(169·50±13·81)ms,P<0·05],而ERP不同程度地延长,且TDE增大。在假手术组,MAP时程和ERP没有明显变化。2组3层心肌之间MAP时程是一致的,不存在TDR。结论:急性缺血时MAP时程缩短,但3层心肌之间没有差别,而ERP延长伴随TDE增大。这可能在急性缺血时心律失常的发生中扮演重要角色。Objective：To investigate the effect of acute ischemia on the electrophysiological characteristics of the three layers myocardium of canine in vivo. Method：Twelve canines were divided into two groups randomly： acute ischemia （AI） group and sham operation （SO） group. With the monophasic action potential （MAP） technique, MAP and effective refractory period （ERP） of the three layers myocardium were measured by specially designed plunge needle electrodes and the transmural dispersion of repolarization （TDR） and transmural dispersion of ERP （TDE） were analyzed. Result：In AI group, MAP duration（MAPD） shortened from （201.67±21.42） ms to （169.50± 13.81）ms （P 〈 0.05）, but ERP lengthened in different altitude and TDE increased during acute isehemia. In the SO group, MAPD and ERP did not change almost. Among of the three layers myocardium of canine, MAP duration was similar in two groups. Conclusion：During acute ischemia, MAPD shortened sharply and there was not difference in MAPD among of the three layers myocardium. But ERP lengthened concomitant with TDE increased during acute ischemia, which may play an important role in the occurrence of arrhythmias induced by acute ischemia. These findings may have important implications in arrhythmogenesis.

关 键 词：心肌缺血 单向动作电位 有效不应期 

分 类 号：R542.2[医药卫生—心血管疾病]