Cardiac sympathovagal interaction and late arrhythmic events after acute myocardial infarction

We assessed the prognostic power of both autonomic indexes and other markers of arrhythmic risk in 72 postinfarction patients. In the 3rd week after AMI, all patients underwent left ventricular ejection fraction measurement, signal-averaged ECG, BRS evsaluation, 24 h Holter monitor analysis for ventricular ectopic activity and heart rate variability. At a mean follow-up of 14 ± 6 months, 9 patients (12%) had an arrhythmic event. At multivariate analysis, only BRS and filtered QRS complex duration at signal-averaged ECG were found to be independent predictors of arrhythmic events. The data suggest that evaluation of autonomic function represents an essential part in arrhythmic risk stratification after AMI; BRS and signal-averaged seem to be the most appropriate methods for predicting postinfarction arrhythmic events.