Absence of first-pass isolation is associated with poor pulmonary vein isolation durability and atrial fibrillation ablation outcomes.

BACKGROUND: Pulmonary vein (PV) reconnection is the main cause of atrial fibrillation (AF) recurrence. This study aimed to examine the effect of first-pass PV isolation (PVI) on PV reconnection frequency during the procedure and on AF ablation outcomes. METHODS: This retrospective study included 446 patients with drug-refractory AF (370 men, aged 64 ± 10 years) who underwent initial PVI using an open-irrigated contact force catheter between January 2015 and October 2016. We investigated the effect of first-pass PVI on PV reconnection during spontaneous PV reconnection and dormant conduction after an adenosine triphosphate challenge. RESULTS: First-pass PVI was achieved in 69% (617/892) of ipsilateral PVs, of which we observed PV reconnection during the procedure in 134 (22%) PVs. This value was significantly lower than that observed in those without first-pass PVI (50%, 138/275) (P < .0001). We divided the subjects into two groups based on the presence or absence of first-pass PVI in at least one of two ipsilateral PVs: first-pass (n = 383, 86%) and non-first-pass groups (n = 63, 14%). The 2-year AF recurrence-free rate was significantly higher in the first-pass group than in the other group (75% vs 59%, log-rank P = .032). In 78 patients with repeat AF ablation, the PV reconnection rate in the second procedure was significantly lower in PVs that had first-pass isolation in the first procedure (34% vs 73%, P < .0001). CONCLUSIONS: Absence of first-pass PVI was associated with a higher frequency of spontaneous PV reconnection and dormant conduction and poor ablation outcomes. First-pass isolation may be a useful marker for better PVI durability.

Comparison of the Safety and Efficacy of Automated Annotation-Guided Radiofrequency Ablation and 2nd-Generation Cryoballoon Ablation in Paroxysmal Atrial Fibrillation.

BACKGROUND: Automated ablation lesion annotation with optimal settings for parameters including contact force (CF) and catheter stability may be effective for achieving durable pulmonary vein isolation. Methods and Results: We retrospectively examined 131 consecutive patients who underwent initial catheter ablation (CA) for paroxysmal atrial fibrillation (PAF) by automatic annotation system (VISITAG module)-guided radiofrequency CA (RFCA) (n=61) and 2nd-generation cryoballoon ablation (CBA) (n=70) in terms of safety and long-term efficacy. The automatic annotation criteria for the RFCA group were as follows: catheter stability range of motion ≤1.5 mm, duration ≥5 s, and CF ≥5 g. We ablated for >20 s with a force-time integral >150 gs at each site, before moving to the next site. Each interlesion distance was <6 mm. Procedural complications were more frequent in the CBA group (1.6% vs. 10.0%, P=0.034). Across a median follow-up of 2.98 years, 88.5% and 70.0% of patients in the RFCA and CBA groups, respectively, were free from recurrence (log-rank test, P=0.0039). There was also a significant difference in favor of RFCA with respect to repeat ablations (3.3% vs. 24.3%, log-rank test, P=0.0003). CONCLUSIONS: RF ablation guided by an automated algorithm that includes CF and catheter stability parameters showed better long-term outcomes than CBA in the treatment of patients with PAF without increasing complications.