Five-year follow-up outcome after catheter ablation of persistent atrial fibrillation using a sequential biatrial linear defragmentation approach: What does atrial fibrillation termination during the procedure imply?

BACKGROUND: A paucity of data exists about long-term outcomes after catheter ablation of persistent atrial fibrillation (AF). The mechanisms of AF are still unclear.

OBJECTIVE: The purpose of this study was to evaluate the 5-year outcome after persistent AF ablation using sequential defragmentation approaches and to identify the prognostic factors.

METHODS: One hundred thirty-five patients with persistent AF (age 62 ± 9 years, 76 longstanding persistent AF) underwent catheter ablation using biatrial linear defragmentation approaches consisting of substrate modification for eliminating AF after pulmonary vein antrum isolation. Procedures were stopped when AF terminated; however, AF termination was not pursued after predetermined substrate modification.

RESULTS: AF terminated in 69 patients (51%). Total procedural and fluoroscopic times were 145.4 ± 36.1 minutes and 35.1 ± 14.3 minutes, respectively. Median [25th, 75th percentiles] follow-up was 60 [26.0-64.0] months, with 1.9 ± 0.8 procedures per patient. Arrhythmia-free survival after multiple procedures was 86.8%, 73.1%, 62.6%, and 53.8% (39 patients on antiarrhythmic drug therapy) at 1, 2, 3, and 5 years, respectively. Multivariate analyses revealed that AF termination (hazard ratio [HR] 3.043, 95% confidence interval [CI] 1.605-5.767, P = .001) was the sole independent predictor of long-term arrhythmia freedom, and arrhythmia freedom at 5 years was 70.0% and 31.8% in patients with and without AF termination (P = .0007). Five-year freedom from crossover to rate control strategies was 86.5%, and AF termination (HR 3.558, 95% CI 1.171-10.812, P = .025) was also the sole predictor.

CONCLUSION: Catheter ablation of persistent AF using the sequential defragmentation approach provided limited long-term freedom of arrhythmias often requiring multiple procedures. AF termination was the sole factor predicting freedom from both arrhythmia recurrence and crossover to rate control strategies during long-term follow-up.