急性冠脉综合征患者窦性心率震荡变化特点及其与心率变异性的相关性研究

目的分析急性冠脉综合征（ACS）患者窦性心率震荡（HRT）指标变化特点及其与心率变异性（HRV）的相关性。方法应用相应的分析软件对与59名健康体检者和161例确诊为ACS的患者24h动态心电图检查结果进行分析，检测HRT参数震荡初始（TO）、震荡斜率（TS）和HRV时域指标24h正常RR间期标准差（SDNN）、全程相邻窦性R—R间期之差的均方根值（rMSSD）、相邻正常RR间期差值〉50ms的心搏数占总RR间期数的百分比（PNN50）。将ACS组分为不稳定型心绞痛（UAP）组和急性心肌梗死（AMI）组，比较HRT、HRV指标和HRT异常的发生率在各组间的差异，进一步探讨ACS患者HRT和HRV指标相关性。结果与健康对照组比较，UAP组及AMI组TO明显增高，TS显著降低（均P〈0．01）；UAP组及AMI组间TO和TS无显著差异。UAP组及AMI组HRT异常率较对照组显著升高（X^2=5．385，P〈0．05；r=9．227，P=0．01）。UAP组及AMI组HRV指标SDNN、rMSSD、PNN50较对照组显著降低（均P〈0．01），AMI组SDNN较UAP组降低（P〈0．05），rMSSD、PNN50差异无统计学意义。ACS患者的TO与SDNN呈负相关（r=-0．26，P=0．031），与rMSSD、PNN50不相关，TS与SDNN、PNN50、RMSSD呈正相关，其中和SDNN的相关性最强（r=0．301，P=0．047）。结论HRT可作为ACS危险分层的一项新的心电学筛选指标。ACS患者HRT、HRV变化从不同方面反映心脏迷走神经的功能受损，二者互相联系又相互独立。

Characteristics of heart rate turbulence and its relationship with heart rate variability in patients with acute coronary syndrome

Objective To investigate the characteristics of heart rate turbulence （HRT） and its relationship with heart rate variability （HRV） in patients with acute coronary syndrome （ACS）. Methods 161 patients with ACS and 59 healthy controls were chosen. Patients with ACS were divided into unstable angina pectoris （UAP） group and acute myocardial infarction （AMI） group. HRT including turbulence onset （TO）, turbulence slope （TS） and HRV including SDNN, rMSSD, PNNS0 were determined by 24 hour ambulatory electrocardiogram in all subjects. The value of HRT and HRV were compared among UAP group, AMI group and control group. The relationship between HRT and HRV was analyzed. Results The levels of TO in patients with ACS were higher than those of the controls （P〈0.01） and TS were significantly lower than those of controls （P〈0.01）. There were no variances of HRT parameters in patients with UAP or AMI. The incidence of abnormal HRT in UAP group and AMI group were significantly higher than those of controls （X^2=5.385,P〈0.05, X^2=9.227,P=0.01）. The levels of SDNN, rMSSD, PNN50 in the patients with ACS were significantly lower than those of controls （P〈0.01）. The level of SDNN in AMI group was lower than that of UAP group （P〈0.05）. There were no variances of rMSSD, PNN50 in patients with UAP or AMI. In patients with ACS, TO was negatively correlated with SDNN （r=-0.26, P=-0.031 ）. TS displayed positive correlation with SDNN, PNN50 and rMSSD （P〈0.05）. Conclusion HRT can be used as a new valuable marker for risk stratification in ACS patients. HRT and HRV are two indices for deter- mination the dysfunction of autonomic nervous system.