Characterizing clinical outcomes and factors associated with conduction gaps in VISITAG SURPOINT-guided catheter ablation for atrial fibrillation.

Purpose: Although usefulness of VISITAG SURPOINT (VS) on pulmonary vein isolation (PVI) in catheter ablation of atrial fibrillation has been reported, optimal VS thresholds can depend on the inter-tag distance (ITD) and vice versa. We validated the efficacy of PVI with lower target ITDs and VS values than in previous studies.

Methods: Retrospective review of consecutive patients (N = 100) with paroxysmal (n = 32) or persistent AF (n = 68) undergoing VS-guided ablation between 09/2018 and 08/2019 was conducted. All procedures were performed by two operators. Target VS values were 425 (anterior), 375 (posterior), and 325 (near the esophagus). Target ITD was 4 mm.

Results: Acute PVI was achieved in all cases, however, 13 residual gaps in 12 patients were observed after initial encirclement (first pass isolation: 88%). Ten gaps due to spontaneous PV reconnections (PVR) were found in nine patients (9%). These 23 gaps had similar median VS (gap-related vs non-gap: 429 vs 410,  = .4545) and power (36 vs 36W,  = .4843), higher contact force (13.8 vs 11.0g,  = .0061), and larger ITD (5.3 vs 3.7mm,  < .001) when compared to the remaining tags. Only ITDs were independently associated with gap formation in multivariate analysis. One-year Kaplan-Meier freedom from any atrial arrhythmia was 87.2%. Eight patients received repeat ablation (8.1%) and of these, 6 (75%) were free from PVR.

Conclusion: Favorable rates of first pass isolation, acute PVR, and long-term procedure success were achieved using lower VS values than in previous reports. With a target VS value of 375-425, ITDs of 4 mm was sufficient for durable PVI.