Outcomes after repeat ablation of ventricular tachycardia in structural heart disease: An analysis from the International VT Ablation Center Collaborative Group

Background Data evaluating repeat radiofrequency ablation (>1RFA) of ventricular tachycardia (VT) are limited. Objective The purpose of this study was to determine the safety and outcomes of VT >1RFA in patients with structural heart disease. Methods Patients with structural heart disease undergoing VT RFA at 12 centers with data on prior RFA history were included. Characteristics and outcomes were compared between first-time (1RFA) and >1RFA patients. Results Of 1990 patients, 740 had >1RFA (mean 1.4 ± 0.9, range 1–10). >1RFA vs 1RFA patients did not differ with regard to age (62 ± 13 years vs 62 ± 13 years), left ventricular ejection fraction (33% ± 13% vs 34% ± 13%), or sex (88% vs 87% men), but they more often were nonischemic (53% vs 41%), had implantable cardioverter–defibrillator shocks (70% vs 63%) or VT storm (38% vs 33%), and had been treated with amiodarone (55% vs 48%) or ≥2 antiarrhythmic drugs (22% vs 14%). >1RFA procedures were longer (300 ± 122 minutes vs 266 ± 110 minutes), involved more epicardial access (41% vs 21%), induced VTs (2.4 ± 2.2 vs 1.9 ± 1.6) and only unmappable VTs (15% vs 9%), and VT was more often inducible after RFA (42% vs 33%, all P <.03). Total complications were higher for >1RFA vs 1RFA (8% vs 5%, P <.01), mostly related to pericardial effusion (2.4% vs 1.3%, P =.07) and venous thrombosis (0.8% vs 0.2%, P =.06). VT recurrence was higher for >1RFA vs 1RFA (29% vs 24%, P <.001). Survival was worse for >1RFA vs 1RFA if VT recurred (67% vs 78%, P =.003) but was equivalent if successful (93% vs 92%, P =.96). Conclusion Patients requiring repeat VT ablation differ significantly from those undergoing first-time ablation. Despite more challenging ablation characteristics, VT-free survival after repeat ablations is encouraging. Mortality is comparable if VT does not recur after RFA at specialized centers.