MANAGEMENT OF VENTRICULAR-FIBRILLATION WITH TRANSVENOUS DEFIBRILLATORS WITHOUT BASE-LINE ELECTROPHYSIOLOGIC TESTING OR ANTIARRHYTHMIC DRUGS

Introduction: Baseline electrophysiologic study (EPS) is routinely per formed in patients resuscitated from ventricular fibrillation (VF) to risk stratify and select patients for chronic antiarrhythmic drug ther apy. The role of FP testing prior to insertion of a multiprogrammable implantable cardioverter defibrillator (ICD), however, is unclear. Met hods and Results: This study was a retrospective review of outcome in 66 survivors of an initial episode of out-of-hospital VF not associate d,vith a Q wave myocardial infarction or reversible causes, treated wi th transvenous ICDs as first-line therapy. Patients were excluded from the study if they had a previous history of monomorphic ventricular t achycardia (VT), a clinical history suggestive of supraventricular tac hycardia, or had undergone preoperative EP testing. Fifty-two of the p atients (79%) were male with an average age of 58 +/- 11 years. Corona ry artery disease was present in 43 patients (66%), cardiomyopathy in 15 patients (23%), and valvular heart disease in 1 patient (1.5%). Sev en patients (11%) had no detectable structural heart disease. The mean left ventricular ejection fraction was 0.40 +/- 0.16. With an average follow-up of 25 +/- 12 months, survival free of death from any cause was 100%. Twenty-three patients (35%) experienced 48 episodes of recur rent rapid VT or VF (average cycle length: 236 +/- 47 msec) treated by their device. The mean time to first therapy was 223 +/- 200 days. On ly one of these patients also received antitachycardia pacing for two episodes of VT. One patient (1.5%) temporarily received amiodarone aft er removal of an infected device that was subsequently replaced. No ot her patient received antiarrhythmic drug therapy. Conclusion: After a cardiac arrest due to primary VF, select patients treated with multipr ogrammable ICDs can be managed successfully without baseline EPS or an tiarrhythmic drug therapy.