Xiaodong Zhang1, MD, PhD, Ruike Yang1 2, MD, Luigi Di Biase1, MD, PhD, FHRS1 Division of Cardiology, Department of Medicine, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York2 Division of Cardiology, Department of Medicine, Henan Provincial People’s Hospital, Zhengzhou, ChinaCorrespondence : Dr Luigi Di Biase, Montefiore Medical Center, Albert Einstein College of Medicine, 111 East 210th St, Bronx, NY 10467. E-mail address: dibbia@gmail.com .Keywords : narrow complex tachycardia, dual atrioventricular nodal non-re-entrant tachycardia, dual atrioventricular nodal re-entrant tachycardia, autonomic nervous system

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%).