哌仑西平对兔急性心肌缺血心率变异与心电生理的影响

Effect of Pirenzepine on Heart Rate Variability and Cardiac Electrophysiology during Acute Myocardial Ischemia in Rabbits

目的 观察小剂量哌仑西平对兔急性心肌缺血时心率变异与心电生理的影响 ,为临床应用提供实验理论依据。方法 建立兔急性心肌缺血模型 ,采用心率变异的时域指标及频域指标测定心肌缺血时心脏自主神经功能 ,应用心电生理研究方法测定心肌缺血时心电生理参数 :心室有效不应期 (VERP) ,心室有效不应期离散度 (VERPD) ,QT离散度(QTD) ,心室颤动阈值 (VFT)的变化 ,比较哌仑西平预处理组与对照组各项指标。结果 兔急性心肌缺血时 ,哌仑西平预处理组较对照组心率变异时域指标增加 ,频域指标VLF、LF与LF/HF降低 ,HF增高 ;心电生理指标VERPD降低 ,QTD降低 ,VFT增高。相关性分析显示心率变异指标与VFT相关。结论 小剂量哌仑西平预处理能改善兔急性心肌缺血时的心电生理不稳定状态 ,增加心室颤动阈值。此作用与提高心脏迷走神经活性有关。

Objective The study is aimed at observing the effect of low dose pirenzepine on heart rate variability and cardiac electrophysiology in the myocardial ischemia model of rabbits. Methods On the model, heart rate variability parameters including time domain (SDNN, rMSSD, CV, HRVI) and power domain (VLF, LF, HF, LF/HF) were assessed. Cardiac electrophysiological parameters (VERPD, QTD, VFT) were also measured with electrophysiological methods. These parameters between the pirenzepine pretreatment group and the control group were compared. Results When acute myocardial ischemia happened, in pirenzepine pretreatment group, SDNN, rMSSD, CV, HRVI and HF increased; VLF, LF, LF/HF, VERRD and QTD decreased and VFT increased ( P <0.01). The parameters of heart rate variability had significant correlation with VFT.Conclusion The pretreatment of low dose pirenzepine enhanced the electrical stability and increased the ventricular fibrillation threshold in acute myocardial ischemia through increasing cardiac parasympathetic activity.