Durability of pulmonary vein isolation: Does the pulsed field ablation system matter?

BACKGROUND: Durable pulmonary vein isolation (PVI) is considered the "Achilles' heel" of atrial fibrillation ablation. Although pulsed field ablation (PFA) is increasingly used owing to its nonthermal, tissue-selective properties, comparative data regarding chronic lesion durability across different PFA platforms remain limited. OBJECTIVE: This study aimed to compare chronic PVI durability and pulmonary vein (PV) reconnection patterns after index ablation with FARAPULSE (pentaspline) and Volt (balloon-in-basket) catheters. METHODS: We retrospectively reviewed consecutive patients undergoing repeat ablation at 2 centers (between May 2023 and September 2025) after a de novo PFA procedure using either a pentaspline (n = 86) or a balloon-in-basket catheter (n = 46). High-density voltage mapping was used to assess the PV and posterior wall. Endpoints included lesion durability and vein reconnection rates. A propensity score-matched sensitivity analysis (n = 34 pairs) addressed baseline imbalances to compare clinical outcomes. RESULTS: Over a median follow-up of 14.3 months (interquartile range 5.9-18.9), 18 patients (9 in each group) experienced clinical recurrence, 17 of whom underwent repeat procedures (balloon-in-basket n = 9; pentaspline n = 8). PV-level reconnection was 2.9% (1 of 35) with balloon-in-basket vs 28.1% (9 of 32) with pentaspline catheter (P = .003). Patient-level durability was significantly higher with balloon-in-basket (88.9% vs 37.5%; P = .049). Despite superior lesion durability, the balloon-in-basket cohort had a numerically higher but nonsignificant clinical recurrence rate (19.6% vs 10.5%; P = .12), as confirmed by equivalent recurrence rates in the propensity-matched cohort (20.6% vs 17.6%; P = 1.000). Posterior wall isolation was associated with significantly lower arrhythmia recurrence across the combined cohort (4.3% vs 17.6%; P = .031). CONCLUSION: The balloon-in-basket PFA platform demonstrated significantly greater chronic PVI durability than the pentaspline system. Propensity score matching confirmed that this durability advantage was not attributable to baseline substrate differences. These platform-specific differences are clinically meaningful and warrant prospective validation.