Low voltage area guided substrate modification in nonparoxysmal atrial fibrillation: A systematic review and meta-analysis.

BACKGROUND: Low voltage areas (LVAs) on left atrial (LA) bipolar voltage mapping correlate with areas of fibrosis. LVAs guided substrate modification was hypothesized to improve the success rate of atrial fibrillation (AF) ablation particularly in nonparoxysmal AF population. However, randomized controlled trials (RCTs) and observational studies yielded mixed results. METHODS: The databases of Pubmed, EMBASE and Cochrane Central databases were searched from inception to August 2022. Relevant studies comparing LVA guided substrate modification (LVA ablation) versus conventional AF ablation (non LVA ablation) in patients with nonparoxysmal AF were identified and a meta-analysis was performed (Graphical Abstract image). The efficacy endpoints of interest were recurrence of AF and the need for repeat ablation at 1-year. The safety endpoint of interest was adverse events for both groups. Procedure related endpoints included total procedure time and fluoroscopy time. RESULTS: A total of 11 studies with 1597 patients were included. A significant reduction in AF recurrence at 1-year was observed in LVA ablation versus non LVA ablation group (risk ratio [RR] 0.63 (27% vs. 36%),95% confidence interval [CI] 0.48-0.62, p < .001]. Also, redo ablation was significantly lower in LVA ablation group (RR 0.52[18% vs. 26.7%], 95% CI 0.38-0.69, p < .00133). No difference was found in the overall adverse event (RR 0.7 [4.3% vs. 5.4%], 95% CI 0.36-1.35, p = .29). CONCLUSION: LVA guided substrate modification provides significant reduction in recurrence of all atrial arrhythmias at 1-year compared with non LVA approaches in persistent and longstanding persistent AF population without increase in adverse events.