Standardized Stimulation Protocol to Predict the Long-Term Success of Radiofrequency Ablation of Postinfarction Ventricular Tachycardia

O'DONNELL, D., et al.: Standardized Stimulation Protocol to Predict the Long-Term Success of Radiofrequency Ablation of Postinfarction Ventricular Tachycardia. Background: The ability to predict the success of radiofrequency ablation (RFA) is an essential step in the management of ventricular tachycardia (VT) in patients with ischemic heart disease. Methods: This study tested a standardized programmed stimulation protocol and pre-specified definitions of procedural outcome. Consecutive patients referred for RFA of delayed post infarction VT were enrolled. Programmed stimulation was performed at the beginning and the end of an RFA procedure, and consisted of an 8 beat drive followed by up to 5 extrastimuli. Immediate success was defined as no inducible monomorphic VT, and a modified result was defined as the inducibility of VT with >2 extrastimuli beyond those required at baseline. Procedural failure was defined when these criteria were not met. Recurrences of sustained VT and arrhythmic deaths were monitored during long-term follow-up. Results: The study enrolled 112 patients. Immediate procedural success was achieved in 38%, a modified result in 34%, and procedural failure in 28% of patients. During a mean follow-up of 78 ± 16 months, recurrent sustained VT was observed in 25 patients. VT recurrence was 3% (3/79) in patients with a successful or modified result, compared with 67% (22/33) in those who had undergone unsuccessful procedures (P < 0.001). Conclusions: This standardized stimulation protocol and definitions of procedural success, enabled us to predict with high accuracy a VT recurrence-free long-term follow-up. This may have implications in recommending devices or other treatments after RFA for postinfarction VT. (PACE 2003; 26[Pt. II]:348–351)