评价狗心肌缺血性室性心律失常的电生理学方法

用冠状动脉Harris二期结扎并部分再灌注法及心肌梗塞恢复期的心脏程控刺激技术(PES),进行心电生理检查并诱发与终止室性心动过速(VT)和心室纤颤(VF),建立了狗心肌缺血/再灌注后VT/VF的在体心脏电生理学研究方法,对该方法的可靠性、实用性及其临床相关性进行了探讨。结果表明,狗心肌缺血/再灌注5～8d后用PES能可靠地、重复地诱发出VT/VF,再灌注的梗塞心肌是其电生理异常的病理基础,该方法具有较好的重复性,是一种有价值的电生理学研究方法。

ELECTROPHYSIOLOGIC METHOD FOR EVALUATING THE ISCHEMIC VENTRICULAR TACHYARRHYTHMIAS IN THE INFARCTED CANINE HEART

Twelve healthy adult mongrel dogs underwent programmed electrical stimulation (PES) 5-8 days after acute myocardial infarction (AMI). Plunge electrodes were inserted at multiple intramyocardial sites in areas of normal and infarcted myocardium to evaluate eletrophysiologic properties. The electrophysiologic effects of procainamide (PD) were observed in 6 dogs. In this model, infarcts were mottled, with close interspersing of normal and abnormal myocardium, the excitability threshold (ET) and effective refractory period (ERP) tended to increase within areas of infarction, and marked disparities in ET and ERP were observed between normal and infarct regions. Using routing methods of PES, ventricular tachycardia (VT) or ventricular fibrillation (VF) could be reproducibly initiated. The PES-induced VT / VF was prevented in 5 out of 6 PD-treat-ed dogs. Normal saline did not prevent PES-induced VT/VF. The results indicated that PES-induced VT / VF were highly reproducible and reliable. This canine model is a worthy and reliable model.