扩张型心肌病患者心率变异时域指标变化与心血管事件发生的相关性

目的 :探讨扩张型心肌病患者HRV变化与心血管事件发生的相关性。方法 :采用 2 4h动态心电图对 99例扩张型心肌病患者进行心率变异 (HRV)分析 ,回顾性分析本院 1997年 8月至 2 0 0 2年 8月进行动态心电图检查的 99例扩张型心肌病患者之病历资料 ,分析全部患者 2 4h动态心电图检查结果 ,记录HRV的时域分析指标 :正常RR间期的标准差 (SDNN) ;5min平均RR间期的标准差 (SDANN) ;相邻RR间期相差≥ 5 0ms占总窦性心搏的百分数 (PNN5 0 )。结果 :DCM的HRV时域分析指标SDNN、SDANN、PNN5 0显著低于对照组P <0 .0 5。以HRV的时域指标SDNN低于 6 0ms、PNN5 0低于 4 .0和心功能指标LVEF <30 %为联合预测心血管事件发生的敏感性为 78% ,特异性为 71% ,阳性预测值为 70 %。结论 :扩张型心肌病患者HRV减低增加了心血管事件的发生率 ,对预测心血管事件的发生有一定的临床价值。

Relationship between Time-domain Index of Heart Rate Variability and Incidence of Cardiovascular Events in Dilated Cardiomyopathy

Objective:To analyze the relationship between time-domain index of the heart rate variability (HRV) determined by 24-hour ambulatory electrocardiography and the incidence of cardiovascular events(CVE) in 99 patients with dilated cardiomyopathy (DCM) Methods: Parameters of heart rate variability (HRV) determined by 24-hour ambulatory electrocardiography in 99 DCM patients and 40 normal subjects from August 1997 to August 2002 in our hospital were analyzed. The time-domain index of HRV included standard deviation of normal-to-normal R-R intervals (SDNN), standard average deviation of normal-to-normal RR intervals (SDANN) and percentage of differences between adjacent normal RR intervals exceeding 50 milliseconds(PNN50). Incidence of cardiovascular events after 24-hour ambulatory electrocardiography in all studied subjects were recorded. Results: SDNN, SDANN and PNN50 were significant lower in DCM patients than those in normal subjects. SDNN <60 ms, PNN50< 4.0 and LVEF<30% can be combined to predict the CVE in DCM patients with high 78% sensitivity, 71% specificity, and 70% positive predictive value. Conclusion:The decreased HRV correlate with increased CVE and may have important value for predicting CVE in the DCM patients