Operation for ventricular tachyarrhythmias: Refining current treatment strategies

For many patients with ventricular tachyarrhythmias, the optimal choice of palliative or curative therapies is not yet well established. To refine optimal current treatment strategies, baseline patient characteristics were studied in relation to likelihood of successful outcome in 240 consecutive patients undergoing operation for treatment of ventricular tachyarrhythmias from 1981 to 1991. Indications for operation were sudden cardiac death or inducible ventricular tachyarrhythmias refractory to medical therapy (or both). Treatment was directed endocardial procedures in 77 patients (32%), other cardiac procedures in 57 patients (24%) (coronary artery bypass grafting in 94% and valve procedure in 14%, either with [35%] or without [65%] concomitant implantable cardioverter-defibrillator), and implantable cardioverter-defibrillator alone in 106 patients (44%). Overall 30-day operative mortality was 5% (70% confidence interval, 4%-7%) and 2-year survival was 74% (70% confidence interval, 71%-77%). Overall 2-year freedom from sudden cardiac death was 97% (70% confidence interval, 96%-98%) and was similar (p = not significant) for all treatment modalities. For each treatment modality, multivariate analysis identified independent risk factors for operative mortality and 2-year tachyarrhythmia recurrence, advanced angina and congestive heart failure New York Heart Association classes, and overall mortality. To characterize better the use and benefit of coronary artery bypass grafting, risk factors related to outcome also were identified for patients stratified according to absence (44 patients) or presence (119 patients) of coronary artery disease excluding patients treated by directed endocardial procedures. In non-coronary artery disease patients, operative mortality was 0%. In coronary artery disease patients, operative mortality was 6% (70% confidence interval 3%-9%) in 65 patients treated with implantable cardioverter defibrillator only, 3% (70% confidence interval, 0%-5%) in 37 patients treated with coronary artery bypass grafting, and 0% in 17 patients treated with implantable cardioverter-defibrillator and coronary artery bypass grafting. Criteria which discriminated coronary artery disease patients treated and not treated by coronary artery bypass grafting were identified. Based on these observations, a refinement of optimal treatment strategies is presented. Whereas all surgical therapies for ventricular tachyarrhythmia convey similar benefits in reducing sudden cardiac death in appropriately selected patients, overall successful outcome is highly dependent on effective treatment of coexistent cardiac disease, in particular, coronary artery disease.