急性心肌梗塞患者心率变异性临床分析

目的　评价心率变异性 (HRV)在急性心肌梗塞 (AMI)患者中的变化及其预后意义。方法　应用动态心电图对 87例AMI患者和 2 5例年龄相当的正常人及AMI患者死亡组和生存组 2 4hHRV时域和频域指标进行对比分析。时域指标为 :正常R -R间期标准差 (SDNN) ,5min平均心率标准差 (SDANN) ,5minR -R间期标准差的平均数 (SDNNIDX) ,相邻R -R间期之差的均方根值 (RMSSD) ,差值 >5 0ms的百分比 (PNN50 ) ;频域指标为 :总频谱 (TF) ,低频 (LF) ,高频 (HF) ,心率谱密度为ms2 /Hz。结果　AMI组与正常组HRV时域和频域对比分析 ,所有指标均显著下降 ,时域中SDNN、SDANN、SDNNIDX和频域中HF下降尤为显著 ,AMI患者死亡组与生存组比较 ,各项指标进一步下降 (P <0 .0 5～ 0 .0 0 1)。结论　AMI患者植物神经活性减低 ,尤以副交感神经活性减低明显 ,且死亡者减低更显著。HRV可做为AMI患者独立的预后指标。

Clinical analysis of heart rate variability in patients with acute myocardial infarction

Objective To study changes and evaluate prognostic value of heart rate variability(HRV) in the patients with acute myocardial infarction(AMI).Methods The HRV, including 24h time- domain and 24h frequency-domain, were measured and compared in 87 AMI patients and 25 health subjects by using 24h dynamic ECG.The time domain components included the standard deviation of normal-to-normal(NN) P-P intervals( SDNN), the standard deviation of the averages of NN intervals in all 5-minute segments of the entire recording(SDANN),the square root of the mean of the squares of differences between adjacent NN intervals( RMSSD), the mean of the standard deviations of all NN intervals for all 5- mintute segments of the entire recording(SDNN IDX), the number of interval differences of successive NN intervals greater than 50ms divided by the total number of the all NN intervals(PNN 50 ).The frequency domain components included total frepuency(TF),low frepuency( LF) and high fregueney(HF) power spectrum density( PSD) was ms z/Hz. Results ⑴ Compared with healthy controls,SDNN、SDANN、SDNN IDX、RMSSD、PNN 50 、TF、HF in AMI patients were reduced markedly (P<0.05-0.001); ⑵ The difference of above-mentioned parameters between the survival group and death group in AMI patients was significant ( P<0.05-0.001).Conclusions The autonomic nervous activity in patients with AMI is reduced;parasympathetic activity has more severe disturbance,which is the one of primary factors cousing death. HRV may be considered as a independent prognostic index in patients with AMI.