Early vs. deferred catheter ablation of ventricular tachycardia in patients of ischaemic substrate: systematic review and meta-analysis of clinical outcomes.

Aims: Ventricular tachycardia (VT) ablation has been shown to reduce the recurrence of VT episodes, but the timing of performing VT ablation (early; at the time of implantable cardioverter defibrillator implantation) or (deferred: after the patient has received ICD shocks) remains controversial. The objective is to conduct a systematic review and meta-analysis of published data from randomized controlled trials (RCTs) in patients with ischaemic cardiomyopathy (ICM) with the aim of comparing outcome of VT ablation stratified by procedural timing. Methods and results: We conducted a meta-analysis of seven landmark RCTs which included patients with ICM who were either at a high risk of VT or experienced VT/ICD shocks. The primary outcome of VT recurrence was compared according to the timing of performing VT ablation (early vs. deferred). In addition, we also compared the secondary outcome of cardiac mortality. Following a comprehensive search strategy, a total of seven RCTs were included within the final analysis. Based on a pooled analysis, early VT ablation was associated with a significant reduction in the primary outcome [pooled odds ratio (OR) of 0.72, 95% confidence interval (CI): 0.55-0.95, Conclusion: The findings from this pooled analysis of seven major RCTs suggest that performing early VT ablation may be beneficial in reducing recurrent VT, ICD shocks, and electrical storm and could also improve cardiac mortality. The benefit of performing early VT ablation was greater in patients with LVEF of >30% amongst this ICM cohort.