Efficacy and safety of pulmonary veins isolation by cryoablation for the treatment of paroxysmal and persistent atrial fibrillation

Abstract
We examined the efficacy and safety of pulmonary vein (PV) isolation, using a cryoballoon catheter. We studied 117 consecutive patients presenting with paroxysmal (n = 92) or persistent (n = 25) atrial fibrillation (AF), who underwent attempts at isolation of 442 PV with a cryoballoon catheter. They were followed in our ambulatory department for every 3 months, or earlier if they reported symptoms. A 48 h ambulatory electrocardiogram was recorded at the 3-month visit. We analysed the immediate and long-term procedural and clinical outcomes. We isolated 385 of 442 PV (87%) with a single cryoballoon application. In 19 patients (16%), an irrigated-tip radiofrequency (RF) catheter was used to create a supplemental focal lesion. A median of nine applications per procedure (range 6–12) was delivered. The mean, overall procedural duration was 155 ± 43 min (range 75–275), and mean duration of fluoroscopic exposure was 35 ± 15 min (range 12–73). At the end of the procedure, 103 patients (88%) were in sinus rhythm. Over a median period of 9.6 months (range 3–12), 11 patients were lost to follow-up. At 3, 6, 9, and 12 months of follow-up, respectively, 79, 79, 79, and 69% of patients presenting with paroxysmal AF had remained recurrence free, vs. 83, 73, 59, and 45% of patients, respectively, with persistent AF. Phrenic nerve palsy was the most frequent, although reversible complication. Pulmonary vein isolation, using a cryoballoon catheter, was completed with a high rate of procedural and long-term success and low rate of minor complications. Supplemented, when needed, by focal RF, cryoballoon ablation was a safe and an effective alternative to a circumferential RF procedure.