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%).