ELECTROCARDIOGRAPHS PREDICTORS OF CARDIAC EVENTS IN MADITII PATIENTS

摘要

Background. There are limited data regarding the prognostic significance of ECG parameters in predicting outcome of postinfarction patients with severe left ventricular dysfunction. Methods and Results. We aimed to evaluate the prognostic significance of standard 12-lead ECG parameters, in 1,120 patients enrolled in the Multicenter Automatic Defibrillator Trial II, for predicting mortality in patients randomized to conventional therapy, and predicting appropriate therapy for ventricular tachycardia and fibrillation, and death in patients randomized to an implantable cardioverter defibrillator (ICD). In addition to clinical variables, the following ECG parameters were tested: heart rate, presence of atrial fibrillation, QRS duration, presence of left bundle branch block (LBBB), QT duration and dispersion. Presence of atrial fibrillation, elevated resting heart rate, LBBB, and prolonged QRS duration indicated increased mortality in univariate analyses, but only QRS duration was found to be predictive for mortality after adjustment for relevant clinical covariates (for each 10 ms increase in QRS duration, there was a 13% increase in the risk of mortality; p=0.003). None of the ECG parameters showed significant and independent prognostic value for predicting arrhythmic events or death in patients with ICDs.Conclusions. In conclusion, among various standard ECG parameters, prolonged QRS duration was found predictive for death and presence of atrial fibrillation also was indicative of increased mortality in MADIT II postinfarction patients with depressed left ventricular function who were randomized to conventional therapy. None of the ECG variables was predictive for arrhythmic events or death in patients treated with ICDs.