QT离散度与充血性心力衰竭患者心脏性猝死的关系

QT Dispersion and Sudden Cardiac Death in Patients with Congestive Heart Failure due to Either Ischemic or Idiopathic Dilated Cardiomyo pathy

目的：探讨ＱＴ离散度与充血性心力衰竭（ＣＨＦ）患者心脏性猝死的关系。方法：分析１６３例ＣＨＦ病人的ＱＴ离散度、血流动力学、心功能及室性心律失常。ＱＴ离散度以１２导联体表心电图上最长和最短的ＱＴ和ＪＴ间期之差及其变异系数计算。结果：平均随访２６±１５个月，心脏性猝死３４例，非猝死型心脏性死亡２５例（心力衰竭１９例，心肌梗塞６例），非心脏性死亡和接受心脏移植７例，存活９７例。心脏性猝死组各ＱＴ离散度参数均显著高于存活组和非猝死组，而后两者之间无差异。多因素Ｃｏｘ模型分析示，ＱＴ离散度增加是心脏性猝死独立危险因素；ＪＴｃ离散度≥８５ｍｓ组和＜８５ｍｓ组３年非猝死生存率分别为３０．８％和９６．６％。结论：ＱＴ离散度增加是心脏性猝死独立危险因素，ＱＴ离散度检测有助于识别ＣＨＦ心脏性猝死高危患者。

Objective:To test the hypothesis that increased QT dispersion is of prognostic value in identifying congestive heart failure patients due to either ischemic or idiopathic dilated cardiomyopathy at the risk of sudden cardiac death (SCD).Methods: In 163 cases of ischemic ( n =126) and idiopathic dilated ( n =37) cardiomyopathy with a left ventricular ejection fraction ≤40%,who were diagnosed by LV angiography,QT dispersions were quantified in terms of maximal-minimal QT/JT intervals (dispersion,d) and the coefficient of variation (cv) of QT and JT intervals.Results:During follow ups (26±15 months) 34 patients died suddenly,19 died from pump failure,6 died from acute myocardial infarction,and 97 survived.Bazett's formula rate corrected JT interval dispersion was found to be 109±23 ms in SCD patients,57±20 ms in survivors,and 55±20 ms in patients who died from pump failure or acute myocardial infarction.Cox′s proportional hazards multivariate analysis revealed that JTc d was the most important independent predictor of SCD.Kapalan Meier survival analysis showed that cumulative SCD free 3 year survival rates were 97.6% in patients with a JTc d<85 ms,and 30.8% in patients with JTc d≥85 ms respectively.Conclusion: Analysis of QT dispersion from the 12 leads surface ECG seems to be a useful screening method for identifying congestive heart failure patients at high risk for SCD.