心肌梗死前后心率变异性的变化及意义

目的　了解心肌梗死前后心率变异性（ＨＲＶ）的变化及心肌梗死前的ＨＲＶ对心肌梗死后心脏猝死的预测价值。方法　２７ 只兔随机分为对照组和心梗组，术前和术后２ 周分别测量ＨＲＶ一次，并行电刺激诱发室颤。结果　梗死组按电刺激能否诱发心室颤动（ＶＦ） 再分为ＶＦ 组和无ＶＦ组，心肌梗死前三组ＨＲＶ无差异，心肌梗死后ＶＦ组ＨＲＶ较心肌梗死前明显降低，无ＶＦ组和对照组无明显变化。结论　心肌梗死后ＨＲＶ 的降低与心脏猝死的发生有关，心肌梗死前ＨＲＶ对心肌梗死后的心脏猝死可能无预测价值。

The change of heart rate variability before and after acute myocardial infarction

Objective To investigate the changes of heart rate variability (HRV) before and after acute myocardial infarction(MI)and the prognostic value of HRV before MI to predict sudden cardiac death. Methods Twenty-seven adult New Zealand rabbits were divided into two groups at random: the control group( n =10) and the MI group( n =17), HRV was measures before and two weeks after MI, the incidence of ventricular fibrillation induced by electric stimulus at last.Results According to the inducibilities of ventricular fibrillation by electric stimulus, the MI group was divided into two subgroups: inducible and non-inducible ventricular fibrillation subgroup There were no difference of HRV measures among three subgroup before MI. After MI, HRV variables in subgroup of inducible ventricular fibrillation were decreased significantly compared to non-inducible VF subgroup. In comparison with HRV before MI, HRV after MI were significantly decreased in inducible ventricular fibrillation subgroup, but had no change in non-inducible ventricular fibrillation subgroup and control group.Conclusions 1) The decrease of HRV variables after MI are predictive for high risk of sudden cardiac death.2) HRV before MI can't predict the risk of sudden cardiac death after MI.