Introduction: Catheter ablation of pulmonary veins (PV) for treatment of atrial fibrillation (AF) is limited by the disparate requirements of sufficient energy delivery to achieve PV isolation while avoiding PV stenosis. The aim of the present study was to evaluate the safety and efficacy of using an irrigated-tip catheter for systematic isolation of PV.
Methods and results: The study population consisted of 136 consecutive patients (109 men, mean age 52 +/- 10 years) with symptomatic, drug-refractory paroxysmal (122) or persistent (14) AF. Cavotricuspid isthmus ablation and systematic radiofrequency isolation of all four PVs (guided by a circumferential mapping catheter) was performed in all patients with a protocol using an irrigated-tip catheter. PV diameter was assessed by selective angiography. The electrophysiologic endpoint of PV isolation was achieved in 100% of patients. Bidirectional cavotricuspid isthmus block was achieved in 99% of patients. Moderate PV stenosis (50% narrowing) was observed in one patient (0.7%) without clinical consequence. No other complications were observed. Reablation procedures were required in 67 patients (49%). After a mean follow-up of 8.8 +/- 5.3 months, 81% of patients were free of AF clinical recurrence, including 66% not taking any antiarrhythmic drugs.
Conclusion: Systematic radiofrequency ablation of PV using an irrigated-tip catheter in patients with atrial fibrillation allows complete isolation of all four PVs with a very low incidence of stenosis.