Ventricular Arrhythmia Burden as a Marker of Success Following Catheter Ablation of Ventricular Arrhythmias in Patients with Structural Heart Disease

Background and objectives: There is little emphasis on the efficacy of catheter ablation for ventricular arrhythmia (VA) when using VA burden reduction as a marker for success. We examined the efficacy of catheter ablation using VA burden, rather than VA recurrence as a marker of success, following catheter ablation of structural heart disease (SHD) related VA.

Methods: Catheter ablation of SHD related VA was performed at a single centre over 4-years. VA episodes and implantable cardioverter defibrillator (ICD) therapies were recorded over the 6-months before and after final ablation. Outcomes were reported in terms of burden reduction and compared to singular VA recurrence.

Results: Overall, 108 patients were included in the study. Mean age 64.2±13.9 years, 86% male, mean left ventricular ejection fraction (LVEF) 42±16%. Median VA episodes and ICD therapy were significantly reduced after ablation (VA before: 10 [interquartile range, IQR: 2-38] vs. VA after: 0 [IQR: 0-2], p<0.001; anti-tachycardia pacing [ATP] before: 16 (IQR: 1.5-57) vs. ATP after: 0 [IQR: 0-2], p<0.001; shocks before: 1 [IQR: 0-5] vs. shocks after: 0 [IQR: 0-0], p<0.001). Procedural success at 6-months was significantly higher when considering ≥75% reduction in VA burden, rather than a singular VA-free survival (83% vs. 67%, p=0.001).

Conclusions: The vast majority (>80%) of patients achieve reduction in VA burden (≥75% reduction) after catheter ablation for VA. This data suggests that catheter ablation is highly therapeutic when procedure success is defined as reduction in VA, rather than using a single VA recurrence as a metric for failure.