The optimal management of anticoagulation therapy during catheter ablation in patients with nonvalvular atrial fibrillation to minimize the risk of periprocedural thromboembolic and bleeding events remains unclear. The traditional approach has been to interrupt the use of an oral vitamin K antagonist (VKA) and to treat patients with a heparin-based regimen. However, the recent open-label, randomized COMPARE study [Di Biase L et al. Circulation. 2014] showed that continuing warfarin during catheter ablation reduced periprocedural stroke and minor bleeding compared with heparin bridging.

The benefit of uninterrupted anticoagulation therapy with a non-VKA oral anticoagulant (NOAC) compared with uninterrupted warfarin has now been shown with both rivaroxaban, in the open-label, randomized VENTURE AF [NCT01729871] study, and with apixaban, in a prospective multicenter registry of patients with nonvalvular atrial fibrillation.

Andrea Natale, MD, St David Medical Center, Austin, Texas, USA, stated that the VENTURE AF study was a phase IIIb, international study designed as an exploratory analysis of this issue since it was not feasible to enroll the large number of patients required to establish noninferiority or superiority of continued anticoagulation. Patients (n = 248) were randomized 1:1 to uninterrupted rivaroxaban 20 mg once daily or uninterrupted warfarin (international normalized ratio, 2.0 to 3.0) prior to catheter ablation and for 4 weeks following the procedure. There was independent, blinded adjudication of all prespecified thromboembolic and bleeding events.

The patient groups were well matched at baseline. The mean age was 59 years, 71% were men, and 91.9% were white. Most patients had paroxysmal AF: 95 (76.6%) in the rivaroxaban group and 87 (70.2%) in the warfarin group (P = .25). Eleven (8.9%) patients in each group had a previous catheter ablation (P = .56). Cardioversion had been performed previously in 47 patients (37.9%) in the rivaroxaban group and 54 (43.5%) in the warfarin group (P = .37).

The activated clotting time levels, according to per-protocol analysis, were significantly lower with rivaroxaban vs warfarin on the day the catheter ablation was performed (mean, 302 vs 332 seconds; P < .001), which has been seen with all of the NOACs, commented Dr Natale.

The total number of adjudicated events was 26 in the rivaroxaban group and 25 in the warfarin group, of which 21 and 18, respectively, were any bleeding event. The primary end point of major bleeding as measured by the GUSTO, ISTH, or TIMI definition of bleeding occurred in 1 patient in the warfarin group and none in the rivaroxaban group. Two thromboembolic events occurred in the warfarin group (1 ischemic stroke and 1 vascular death), and none in the rivaroxaban group. The most frequent minor bleeding event was hematoma or vessel puncture site hematoma, which occurred in 8 patients in the rivaroxaban arm and 10 patients in the warfarin group.

The study was limited by the low number of bleeding events, stated Dr Natale, who also noted that the sample size in this study is similar to that for the largest nonrandomized studies in this setting. Detailed data on the clinical outcomes will be published in the near future.

A prospective multicenter registry study was conducted at 4 centers in the United States and Europe, and it included consecutive patients taking apixaban (5 mg BID) for at least 30 days prior to undergoing radiofrequency catheter ablation. The last dose of apixaban was taken on the morning of the procedure. This analysis included 200 patients with uninterrupted apixaban and 200 patients with uninterrupted warfarin who were matched for age, sex, and type of AF. The patients were mostly men (71.5%), their average age was 65.9 years, and 334 (83.5%) had nonparoxysmal AF. The results were presented in a poster by Luigi Di Biase, MD, St David Medical Center, Austin, Texas, USA, and colleagues.

No differences were found between the apixaban and warfarin groups, respectively, for major bleeding (1% vs 0.5%; P = 1.0) or minor bleeding (3.5% vs 2.5%; P = .56). Total bleeding complications were also similar with apixaban (4.5%) and warfarin (3%, P = .43). The investigators stated there were no symptomatic thromboembolic complications. In a subset of 29 patients who had diagnostic magnetic resonance imaging following ablation, there were no cases of silent cerebral ischemia in the patients treated with apixaban.

The investigators for the VENTURE AF study and the multicenter registry stated that the results indicate that uninterrupted treatment with rivaroxaban and apixaban, respectively, had outcomes similar to that seen with warfarin. These data suggest that uninterrupted therapy with rivaroxaban and apixaban can be considered as a strategy to reduce periprocedural thromboembolic events and results in a risk of major bleeding in patients with nonvalvular atrial fibrillation undergoing catheter ablation similar to that seen with warfarin.