Impact of atrial fibrillation termination on clinical outcome after ablation in relation to the duration of persistent atrial fibrillation.

BACKGROUND: Whether procedural termination of persistent atrial fibrillation (AF) is necessary for optimal clinical efficacy still remains controversial. We sought to characterize the patients with persistent AF in whom procedural AF termination impacted an improved clinical outcome after ablation.

METHODS: We retrospectively assessed 132 patients (61.0 ± 9.3 years, 114 males) undergoing catheter ablation of persistent AF (duration 3 years, median). A stepwise ablation approach including pulmonary vein isolation and atrial substrate ablation targeting complex fractionated and high-frequency electrograms was performed with desired endpoint of AF termination.

RESULTS: Overall, 90 patients (68%) were free from recurrent arrhythmias at 20 ± 11 months of follow-up after one or two procedures. The left atrial diameter and continuous AF duration according to medical history were associated with the outcome (P = 0.002 and P< 0.001, respectively). In multivariate Cox regression analysis, the continuous AF duration was the only independent predictor of recurrent arrhythmias (hazard ratio 1.17, 95% confidence interval 1.10-1.23, P < 0.001). In patients with AF duration of ≥ 3 years, the clinical success was comparable regardless of whether AF termination was achieved or not (log-rank, P = 0.27). In the remaining patients with AF duration of <3 years, procedural AF termination was associated with a higher arrhythmia-free rate than when AF was sustained after ablation (log-rank, P = 0.023).

CONCLUSION: Extensive ablation to terminate AF might not be warranted in patients with a longer AF duration. On the contrary, procedural AF termination could be associated with maintenance of sinus rhythm in patients with a shorter AF duration with a less proarrhythmic substrate. (PACE 2012;35:1436-1443).