Ablation of paroxysmal and persistent atrial fibrillation with multielectrode phased radiofrequency duty-cycled catheters: long-term results from a large cohort of patients.

Background: Catheter ablation is a widely used approach to treat patients with drug refractory paroxysmal atrial fibrillation (PAF) and persistent atrial fibrillation (CAF). The aim of this analysis was to evaluate the long-term safety and efficacy of the multielectrode/phased radiofrequency (RF)/duty-cycled ablation catheters in the treatment of both PAF and CAF in a large cohort of patients.

Methods And Results: From July 2008 to February 2010, 429 consecutive drug refractory symptomatic patients (mean age 60 ± 12 years old, 58% men, 68% PAF, 32% CAF) were treated. Seventy-five patients had two procedures resulting in a total of 504 procedures (procedure mean time: 62 ± 15 min). Following ablation, 4-day continuous Holter monitoring was done every 3 months. Recurrence was defined as any atrial tachyarrhythmia of more than 30 s. At 3 months 97.4% of patients were off antiarrhythmic drugs. During a mean follow-up of 22 ± 5 months, freedom from AF recurrence was 68.5% (95% CI: 63.8-72.6) and higher for PAF than CAF patients. The risk of AF recurrence in PAF patients increased in the presence of hypertension, dyslipidemia, large left atrial diameter (LAD) and low ejection fraction. For CAF patients, the risk of AF recurrence increased with larger LAD and lower ejection fraction. Complications that resolved prior to discharge were observed in nine patients (2.1%) with no strokes/transient ischemic attacks (TIAs).

Conclusion: The ablation of symptomatic PAF and CAF with multielectrode phased radiofrequency/duty-cycled ablation catheters shows long-term safety and effectiveness with relatively short procedure times.