Cryoballoon versus radiofrequency catheter ablation: 3-year follow-up data from the prolonged Norwegian randomized study of persistent atrial fibrillation (NO-PERSAF study)

Abstract

Abstract Background Pulmonary vein isolation (PVI) is still regarded as a cornerstone for treatment of persistent atrial fibrillation (AF). Both radiofrequency ablation (RFA) and cryoballoon ablation (CBA) are frequently employed to achieve PVI. Similar results of both techniques have been reported during short follow-up, but clinical outcomes for long-term follow-up from randomized trials are still missing. Purpose This study aimed to evaluate the effectiveness of PVI performed with CBA compared with RFA in patients with persistent AF over 3 years. Methods For the NO-PERSAF study, 101 patients (63.2±8.6 years old, 80 male, 21 female), with persistent AF (77 persistent AF, 24 long-standing persistent AF) referred to PVI were randomized (1:1) to CBA or RFA and followed for 12 months. All patients participating in the NO-PERSAF study were invited to an extended outpatient evaluation with 12-lead ECG and 7-day Holter. The primary endpoint was any documented recurrent atrial tachyarrhythmia (ATA) lasting longer than 30 s during 3 years after the index ablation procedure (following a 3-month blanking period). The ATA-free survival curves were estimated by Kaplan-Meier method and analyzed by log-rank test. Results One patient crossed over from CBA to RFA group because of equipment problem during index ablation procedure. 99 of the original 101 patients responded (1 died of non-cardiovascular diseases, 1 lost). Freedom from ATA was achieved in 51 (50.5%) of the 101 patients, 28 (54.9%) out of 51 patients in the CBA group and 23 (46.0%) out of 50 patients in the RFA group (Figure 1). No difference of ATA recurrence was found between the two groups (p=0.327). There was significantly (p=0.031) less atrial flutter in the CBA group (7.8%; 4 atypical) compared with the RFA group (22%; 10 atypical, 1 typical). 28 patients received repeat ablations with RFA during the follow-up period, 15 in the CBA group and 13 in the RFA group (1 twice). Freedom from ATA after multiple ablations was achieved in 74 (73.3%) of the 101 patients, 40 (78.4%) out of the 51 patients in the CBA group and 34 (68.0%) out of the 50 patients in the RFA group. No difference of ATA recurrence was found between the two groups (p=0.178, Figure 2) after multiple ablations with RFA for AF and atrial flutter. Noticeably, 2 patients in the CBA group and none in the RFA group received atrioventricular nodal ablation after permanent pacemaker implantation. Conclusions Compared to RFA, PVI performed with CBA showed similar outcome of freedom from ATA over a long-term follow-up of 3 years. However, the incidence of atrial flutter was significantly lower in the CBA group.Figure 1Figure 2