老年心肌梗死患者心率变异性分析

目的：研究老年人心肌梗死1年内的心率变异性（heart rate variability,HRV）,了解心肌梗死后心脏植物神经调节状况.方法：采用时域法五项指标分析50例心肌梗死后1年内门诊随访的老年患者的HRV,并与50例元冠心病证据的老年健康者进行对比.结果：心肌梗死后组正常R-R间期的标准差（SDNN）、节段平均R-R间期的标准差（SDANN）、标准差的平均值（SDNNindex）均明显低于健康对照组（P＜0.01）,相邻R-R间期差值的均方根（RMSSD）、相邻R-R间期差值大于50 ms记数占总R-R间期数的百分比（PNN50）亦较健康对照组降低（P＜0.05）.结论：心肌梗死后1年内老年患者HRV仍有异常改变,则提示植物神经功能失调,并预示严重心律失常及心源性猝死的发生率增高.

Heart Rate Variability in the Elderly with Myocardial Infarction

Objective:To investigate the heart rate variability (HRV) of the elderly with myocardial infarction during one-year period following the onset of the disease and to understand the regulation of cardiac vegetative nerves after myocardial infarction.Methods:Time domain method was applied to measure five indexes of HRV in 50 old patients with myocardial infarction during the first year after the disease on our follow-up program at the out-patient department.50 normal elderly without evidence of coronary artery disease were treated as control.Results: SDNN,SDANN and SDNNindex in the myocardial infarction group were much lower than those in control group (P<0.01);RMSSD,PNN50 of the myocardial infarction group were also reduced (P<0.05).Conclusions:HRV of the elderly with myocardial infarction still changes abnormaly during one-year period after the onset of the disease,indicating vegetative nerves dysfunction and predicting a increasing rate of serious arrhythmia and sudden cardiac death.