Exploratory Analysis of Late Recurrence after First-Time Catheter Ablation for Atrial Fibrillation.

Atrial fibrillation (AF) is common, and recurrence after catheter ablation remains clinically important. We retrospectively explored factors associated with late recurrence after first-time AF ablation in the overall cohort and in paroxysmal AF and persistent/long-standing persistent AF subgroups. Consecutive patients undergoing first-time AF ablation at a single center between January 2017 and March 2022 were included. After excluding patients with documented early recurrence within 90-day blanking period who did not undergo repeat ablation, 304 of 368 eligible patients comprised the primary analytic cohort. Late recurrence was defined as AF, atrial tachycardia, or atrial flutter lasting > 30 seconds between days 91 and 365. Overall, late recurrence occurred in 53 patients (17.4%) and was more frequent in persistent/long-standing persistent AF than in paroxysmal AF (40/135 [29.6%] versus 13/169 [7.7%]). In exploratory paroxysmal AF subgroup analyses, patients with late recurrence were older, shorter, and had higher brain natriuretic peptide levels. In a parsimonious multivariable model adjusted for height, brain natriuretic peptide, and cavotricuspid isthmus ablation, but not fully adjusted for age and sex because of the small event number, greater height was inversely associated with late recurrence (odds ratio per 10-cm increase, 0.54; 95% confidence interval, 0.41-0.90; P = 0.038). No significant associations were found in persistent/long-standing persistent AF. Given the older age of patients with recurrent paroxysmal AF, the small number of events, and possible residual confounding by age, sex, frailty, nutritional status, or unmeasured atrial substrate, this inverse association should be interpreted cautiously as hypothesis-generating rather than confirmatory or causal.