Ten years electrophysiologically guided direct operations for malignant ischemic ventricular tachycardia - Results

During the recent 10 years period worldwide more than 1000 patients underwent an electrophysiologically guided direct operation for malignant ventricular tachycardia in the setting of chronic ischemic heart disease. The published results of these operations as regards relief of ventricular tachycardia and survival are highly variable. The data presented here a largely based on a multi-institutional registry series (n = 665) and the combined Dusseldorf-Birmingham/Alabama (DUS-UAB) ventricular tachycardia surgery experience (n = 216). Data: Survival (hospital deaths included) was 75% one year after operation and 45% at 5 years (DUS-UAB). The respective data of the registry series were 78% and 55%. The most prevalent mode of death in both analyses was acute/subacute/chronic heart failure. More extensive encircling procedures (incisional/cryo) for ventricular tachycardia ablation and the combination of encircling cyroablation and endocardial resection increased the risk of progressive left ventricular dysfunction and death; however, by multivariate analysis the severity of the underlying ischemic heart disease (indicated by NYHA functional class, LVEDP, No. of previous infarcts, and extensiveness of coronary disease) and the absence of a discrete left ventricular aneurysm were more powerful predictors for early and late postoperative mortality than the use of alternative surgical techniques for ventricular tachycardia ablation. Survival was particularly poor after the return of spontaneous sustained ventricular tachycardia. In the combined DUS-UAB experience 79% of the surviving patients were free of the return of ventricular tachycardia or sudden death 1 year after operation and 65% at 5 years; similar data could be calculated from the registry series. The non-use of incisional techniques (partial/complete encircling endocardial myotomy incision) (DUS-UAB), more advanced myocardial damage and functional impairment from previous infarctions, and the absence of a left ventricular aneurysm were the most powerful predictors of surgical failure defined as return of ventricular tachycardia or death early or late postoperatively. In both analyses a positive EPS (clinical ventricular tachycardia re-inducible) early after operation (1-2 weeks) was extraordinarily predictive for later return of spontaneous ventricular tachycardia and/or sudden death (p = .0003). Inferences: The overall results after electrophysiologically guided direct operations for surgical ventricular tachycardia ablation are better than the natural history of the disease. Procedures such as extensive encircling cryoablation techniques which produce irreversible damage to large areas of myocardium contain the highest risk of early postoperative phase death and surgical therapy failure. The most effective surgical technique to ablate arrhythmogenic tissues underlying malignant ventricular tachycardia and preserve ventricular function in this experience are limited (partial) endocardial myotomy incisions. All direct antitachycardiac surgical procedures damage also non-arrhythmogenic contracting left ventricular myocardium and with that necessarily adversely affect the left ventricular structure and function. Therefore they should be kept as limited as possible to encompass and ablate exclusively the arrhythmogenic substrates identified by electrophysiologic mapping. The most powerful predictors of the postoperative prognosis are variables describing the severity of the underlying ischemic heart disease.