Ventricular tachycardia ablation outcomes in electrical storm

Abstract Background Electrical storm (ES) occurs in 7% of cases after defibrillator implantation(1) and is associated with increased mortality, especially in the first 3 months after its diagnosis (2). Catheter ablation has been reported to acutely control nearly all cases of ES, and during the follow-up, 66% of patients were free of ventricular tachycardia recurrence. Compared with medical treatment, catheter ablation for ES is associated with improved mortality outcomes(3). Objectives To compare the outcomes of catheter ablation of patients presenting to those undergoing catheter ablation for other indications. Methods We developed a retrospective cohort of all patients who underwent ventricular tachycardia ablation at our center from 2018 to 2024. Baseline characteristics and intraprocedural findings were collected. Twelve-month survival, ventricular tachycardia recurrence rates, and the composite outcome of freedom from death, heart transplantation, and left ventricular assist device placement were assessed to compared outcomes between ES vs no-ES patients. Kaplan-Meier curves and the log-rank test were used to compare freedom from ventricular tachycardia recurrence between groups. Results Ninety-one patients underwent catheter ablation for the treatment of ventricular arrhythmia. ES was the indication for catheter ablation in 23% of cases. ES patients more frequently had a history of previous catheter ablation (33% vs. 12%, p=0.039) and had lower left ventricular ejection fraction (28% vs. 33%, p=0.047). ES presented higher 12-month mortality (35% vs. 11%, p=0.03) and higher 6-month composite outcome (26% vs. 6.6%, p = 0.031). There were no differences in freedom form ventricular tachycardia recurrence between groups (log-rank 0.33). Conclusion ES is a common indication for ventricular catheter ablation. ES patients have worse baseline characteristics and higher probability of developing 6-month composite outcome and 12-month mortality. Ventricular tachycardia recurrence rates after catheter ablation were not different between ES vs non-ES patients.Baseline Characteristics and Outcomes Freedom from VT recurrence