扩张型心肌病患者心率减速力的临床研究

摘要

Objective: To study the change of heart rate deceleration capacity ( DC) in patients with dilated cardiomyopathy (DCM) and its relationship with left ventricular ejection fraction (LVEF) and heart rate variability (HRV). Methods; Using 24h Holter recordings and Echocardiography, DC, LVEF, time and frequency domain parameters of HRV were measured by computer in 32 patients with DCM and 34 healthy adults ( control group). DC, LEVF, standard deviation of normal R-R intervals ( SDNN) , squares of differences between adjacent NN intervals ( RMSSD ) , low frequency power (LFn) and high frequency power(HFn) were compared between the two groups, the relationship between DC, LVEF and HRV were studied in patient with DCM. Results; The median value of DC in the patients with DCM was significantly lower than that in control group ( 3. 28 ± 2. 30 ms vs 6. 91 ±1.43ms, P < 0. 01) . Incidence of abnormal DC in the DCM group was 89.7% , which was significantly higher than that in the control group (P<0. 01). Significant positive correlation between DC and LVEF, time domain indices - SDNN, RMSSD as well as frequency domain indices HFn of HRV parameters were observed (P <0.01). Conclusions; DC is depressed in patients with DCM. DC is a new noninvasive method to assess autonomic nerve function and also a risk prediction of patients with DCM.%目的:研究心率减速力(DC)在扩张型心肌病(DCM)患者中的变化以及与左室射血分数(LVEF)、心率变异性(HRV)之间的关系.方法:32例DCM患者和34例正常人接受24h动态心电图检查和超声心动图检查,计算机分别测定2组患者的DC、LVEF及HRV时域指标(SDNN,RMSSD)与标化的频域指标(LF、HFn)；比较2组患者的DC、LVEF、SDNN,RMSSD、LFn及HFn,并研究DCM患者的DC与LVEF及HRV各指标之间的关系.结果:DCM患者的DC值明显小于正常对照组(3.3±2.3 ms vs 6.9±1.4 ms,P ＜0.01),其异常DC的发生率高达89.7％,明显高于正常对照组(P＜0.01)；DCM组患者的DC与LVEF、SDNN、RMSSD、LFn及HFn之间呈明显的正相关关系.结论:DCM患者的DC值明显降低,DC是一项可用以定量评估DCM患者自主神经张力并筛选高危患者的新的可靠指标.