Predictors of arrhythmic death and cardiac arrest in the ESVEM trial

Background: The purpose of this study was to determine if the presenting ventricular arrhythmia (ventricular tachycardia or ventricular fibrillation/cardiac arrest) predicted the type of arrhythmia recurrence in patients treated with antiarrhythmic drugs. Methods and Results: In the previously reported Electrophysiologic Study Versus Electrocardiographic Monitoring (ESVEM) trial, there were 486 patients who were randomized to antiarrhythmic drug testing guided by electrophysiological study or by ambulatory ECG monitoring. Use of a defibrillator (implantable cardioverter- defibrillator, ICD) without stored electrograms among 81 patients precluded determination of the type of arrhythmia recurrence; thus these patients were censored at the time of ICD implantation. Of the 486 patients, 381 presented with ventricular tachycardia and 105 with cardiac arrest. Over a 6-year follow-up period, 285 of the 486 patients had an arrhythmia recurrence; of these, 97 had an arrhythmic death or cardiac arrest as a first recurrence. In the current analysis, all 129 arrhythmic deaths/cardiac arrests that occurred any time during follow-up were evaluated as end points. Conclusions: Although univariate analysis suggested that there was an association between the presenting arrhythmia and outcome, multivariate analysis failed to substantiate the predictive value of the presenting arrhythmia. Left ventricular ejection fraction was the single most important predictor of arrhythmic death or cardiac arrest. This information may be an important factor in deciding whether to advise ICD therapy.