Role of repeat procedures for catheter ablation of postinfarction ventricular tachycardia

BackgroundIn patients with ischemic heart disease, ventricular tachycardia (VT) is associated with increased mortality and morbidity. Catheter ablation is useful for reducing VT therapies but remains challenging, and recurrences are common.ObjectiveThe purpose of this study was to assess the prognosis and safety of repeat catheter ablation procedures for postinfarct VT and to determine clinical and procedural predictors of outcomes.MethodsFrom a total of 280 patients undergoing catheter ablation of postinfarct VT at one center, 107 consecutive patients having a repeat procedure after one or more prior failed catheter ablation procedures (PFCA group) were compared to 173 patients who underwent a single catheter ablation (SCA group) in the same study period.ResultsOf the PFCA group, 75 (70.1%) had one procedure and 32 (29.9%) had two or more prior ablations. Ventricular function and age were similar between groups. Periprocedural complications occurred in 11.2% of patients in the PFCA group and 8.7% of patients in the SCA group (P = .484). The 1-year VT recurrence rate was higher in the PFCA group compared to the SCA group (32.6% vs 16.6%, P = .001). On multivariable analysis, prior ablation (hazard ratio [HR] 1.84, P = .018), left ventricular ejection fraction (HR 1.04, P = .019), and mean number of induced VTs (HR 1.17, P = .043) were independent predictors of VT recurrence.ConclusionFailure of initial ablation does not preclude subsequent successful ablation for postinfarct VT. Whether healing of prior lesions, change in arrhythmic substrate, or changes in antiarrhythmic therapy are factors that influence recurrence warrants further study.