Vemulapalli, Hema Srikanth

Introduction: Pulmonary Vein Isolation (PVI) has become the cornerstone during ablation of Atrial Fibrillation. The primary goal of the procedure is to prevent potential arrhythmogenic triggers from accessing the main left atrial substrate. However, incomplete fibrosis leading to PV reconnection has been identified as the primary reason for AF recurrence. It is unclear whether immediate voltage mapping and additional lesions delivered to areas of residual or recovered voltages will improve the outcome. This study evaluates the 1-year success and long-term recurrence-free survival in patients who underwent post-procedure voltage mapping (PPVM) to identify residual Low-Voltage Areas (LVAs) to guide the delivery of additional ablation lesions. Methods: We analyzed 588 patients who underwent PVI from 2015 to 2023. Of these, 243 had PPVM done to determine LVAs and guide additional ablation lesions. The control arm comprised 345 patients who underwent PVI by the same operators without PPVM. The primary endpoints were 1-year success and longer-term recurrence-free survival. Secondary endpoints were the incidence of complications and the prevalence of LVAs in patients who underwent PPVM. Results: Patients who underwent remapping were older than the control arm (68.3 vs 65.6 years, p = 0.005). There were no other significant differences in baseline characteristics between the two groups. At 1-year follow-up, the success rates were 79% in the treatment arm compared to 72% in the control arm (p = 0.038). Patients in the intervention arm had a recurrence-free survival rate of 65% and 54% at 2 and 4 years, respectively, compared to 62% and 43% in the control arm (p = 0.044). The prevalence of LVAs in the treatment arm was 56.8%. Additionally, complication rates were not increased in the remapping arm (3% vs 8%, p = 0.012). Conclusion: PPVM-guided incremental ablation lesions improve the 1-year success rate and recurrence-free survival at 2 and 4 years compared to traditional PVI without increasing complications due to additional lesion delivery.

Despite advances in ablative therapies, outcomes remain less favorable for persistent atrial fibrillation often due to presence of non-pulmonary vein triggers and abnormal atrial substrates. This review highlights advances in ablation technologies and notable scientific literature on clinical outcomes associated with pursuing adjunctive ablation targets and substrate modification during persistent atrial fibrillation ablation, while also highlighting notable future directions.