First-Line Ablation of Ventricular Tachycardia in Ischemic Cardiomyopathy: Stratification of Outcomes by Left Ventricular Function

Abstract

Introduction: Randomized controlled trials (RCTs) have shown improved outcomes in patients undergoing first-line catheter ablation of ventricular tachycardia/ventricular fibrillation (VT/VF) in patients with ischemic cardiomyopathy (ICM). Herein, outcomes were stratified based on left ventricular ejection fraction (LVEF). Methods: RCTs evaluating first-line ablation versus medical therapy in patients with VT and ICM were included. Risk estimates and 95% confidence intervals (CI) were measured. Results: Four RCTs with a total of 505 patients (mean age 66 ± 9 years, 89% male, 80% with previous revascularization) were included. Mean LVEF was 35 ± 8%. At a mean follow-up of 24 ± 9 months, a significant benefit in survival-free from appropriate ICD therapies was observed in all patients undergoing first-line catheter ablation compared to medical management (RR 0.70, 95% CI 0.56-0.86). In patients with moderately depressed LVEF (>30-50%), first line VT ablation was associated with a statistically significant reduction in the composite endpoint of survival-free VT/VF and appropriate ICD therapies (HR: 0.52, 95% CI: 0.36-0.76), whereas there was no difference in patients with severely depressed LVEF (30-50%).