OPERATION FOR VENTRICULAR TACHYARRHYTHMIAS - REFINING CURRENT TREATMENT STRATEGIES

For many patients with ventricular tachyarrhythmias, the optimal choic e of palliative or curative therapies is not yet well established. To refine optimal current treatment strategies, baseline patient characte ristics were studied in relation to likelihood of successful outcome i n 240 consecutive patients undergoing operation for treatment of ventr icular tachyarrhythmias from 1981 to 1991. Indications for operation w ere sudden cardiac death or inducible ventricular tachyarrhythmias ref ractory to medical therapy (or both). Treatment was directed endocardi al procedures in 77 patients (32%), other cardiac procedures in 57 pat ients (24%) (coronary artery bypass grafting in 94% and valve procedur e in 14%, either with [35%] or without [65%] concomitant implantable c ardioverter-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% co nfidence interval, 71%-77%). Overall 2-year freedom from sudden cardia c death was 97% (70% confidence interval, 96%-98%) and was similar (p = not significant) for all treatment modalities. For each treatment mo dality, multivariate analysis identified independent risk factors for operative mortality and 2-year tachyarrhythmia recurrence, advanced an gina and congestive heart failure New York Heart Association classes, and overall mortality. To characterize better the use and benefit of c oronary artery bypass grafting, risk factors related to outcome also w ere identified for patients stratified according to absence (44 patien ts) or presence (119 patients) of coronary artery disease excluding pa tients treated by directed endocardial procedures. In non-coronary art ery disease patients, operative mortality was 0%. In coronary artery d isease patients, operative mortality was 6% (70% confidence interval 3 %-9%) in 65 patients treated with implantable cardioverter-defibrillat or only, 3% (70% confidence interval, 0%-5%) in 37 patients treated wi th coronary artery bypass grafting, and 0% in 17 patients treated with implantable cardioverter-defibrillator and coronary artery bypass gra fting. Criteria which discriminated coronary artery disease patients t reated and not treated by coronary artery bypass grafting were identif ied. Based on these observations, a refinement of optimal treatment st rategies is presented. Whereas all surgical therapies for ventricular tachyarrhythmia convey similar benefits in reducing sudden cardiac dea th in appropriately selected patients, overall successful outcome is h ighly dependent on effective treatment of coexistent cardiac disease, in particular, coronary artery disease.