Preventive versus deferred catheter ablation of myocardial infarct-associated ventricular tachycardia: A meta-analysis.

backgroundThe optimal timing of catheter ablation for the treatment of ventricular tachycardia (VT) in patients with ischemic cardiomyopathy remains unclear. Studies examining the impact of early preventive ablation of VT on rates of implantable cardioverter-defibrillator (ICD) therapies and mortality have been limited by small sample size.

objectivesTo conduct a meta-analysis of randomized controlled trials (RCTs) comparing initial catheter ablation and ICD implantation (preventive ablation arm) vs ICD implantation alone (deferred ablation arm) in patients with ischemic cardiomyopathy and VT.

methodsThe primary endpoint was the incidence of appropriate ICD therapy during follow-up. Secondary endpoints included appropriate ICD shock, VT storm, procedural complications, and mortality. Sensitivity analysis, meta-regression, and evaluation of bias were performed.

resultsFour RCTs (n = 505) fulfilled inclusion criteria. During follow-up (mean >22 months for all RCTs), preventive ablation was associated with a significant reduction in ICD therapies (odds ratio [95% confidence interval]: 0.53 [0.36-0.78]). The occurrence of ICD shocks and VT storm were also significantly reduced in the preventive ablation group. Among patients with left ventricular ejection fraction (LVEF) >30%, preventive ablation was associated with marked reduction in ICD therapy when compared to deferred ablation (odds ratio [95% confidence interval]: 0.37 [0.19-0.72]). Overall, there was no difference in mortality between treatment groups.

conclusionsPreventive catheter ablation in patients with ischemic cardiomyopathy decreases ICD therapies, ICD shocks, and VT storm without increasing complications, particularly in patients with LVEF >30%. However, early preventive ablation is not associated with any benefit in mortality.