心率减速率和连续心率减速率在心肌梗死后猝死患者中的变化及其意义

Changes and significance of deceleration capacity of rate and heart rate deceleration runs in sudden death patients after myocardial infarction

目的探讨心率减速率（DC）和连续心率减速率（DRs）在心肌梗死后患者猝死风险的预警价值。方法选自2014年2月～2015年6月接受治疗的200例心肌梗死患者为观察对象。根据其预后分为猝死组（12例）和非猝死组（188例）。回顾性分析其临床资料，观察两组患者DC和DRs水平的差异，比较两组患者心率变异性和相关实验室指标的差异，分析DC和DRs水平与心率变异性、实验室指标的相关性。结果猝死组患者的DC和DRs水平明显低于非猝死组，差异具有统计学意义（P＜0.05）；猝死组患者24h全部正常R-R间期的标准差（SDNN）、24h每5min正常R-R间期平均值的标准差（SDANN）和左室射血分数（LVEF）明显低于非猝死组，差异具有统计学意义（P＜0.05）；DC和DRs水平与SDNN、SDANN和LVEF显著正相关（P＜0.05），而与相邻正常R-R间期差值的均方根值（RMSSD）、NN50计数占总R-R间期数的百分比（%）（PNN50）和左室收缩压（LVPS）无明显相关关系（P＞0.05）。结论心肌梗死后猝死患者的DC和DRs水平较低，且与患者心率变异性等密切相关。

Objective To discuss the value of deceleration capacity of rate (DC) and heart rate deceleration runs (DRs) in early warning of sudden death risk in patients after myocardial infarction (MI). Methods MI patients (n=200) were chosen from Feb. 2014 to Jun. 2015, and divided, according to prognosis, into sudden death group (n=12) and non-sudden death group (n=188). The clinical materials were retrospectively analyzed, and difference in levels of DC and DRs were observed in 2 groups. The differences in heart rate variability (HRV) and relevant laboratory indexes were compared between 2 groups, and correlation among DC, DRs, HRV and relevant laboratory indexes were analyzed. Results The levels of DC and DRs were significantly lower in sudden death group than those in non-sudden death group (P<0.05). SDNN, SDANN and LVEF were significantly lower in sudden death group than those in non-sudden death group (P<0.05). The levels of DC and DRs were positively correlated to SDNN, SDANN and LVEF (P<0.05), and not significantly correlated to RMSSD, PNN50 and LVPS (P>0.05).Conclusion The levels of DC and DRs are lower and closely correlated to HRV in sudden death patients after MI.