Options for Anticoagulant Therapy During Catheter Ablation for Atrial Fibrillation: Safety and Efficiency of Bridging with Dabigatran Compared to Interruption of NOACs

Monitored Patient Population and Anticoagulant Treatment Procedure

A total of 297 patients undergoing catheterization for the treatment of atrial fibrillation between April 2017 and October 2018 were included in the study. 272 of these patients were on NOAC anticoagulant therapy to prevent thromboembolic events. In 137 of them, this therapy was discontinued on the day of the procedure and the patients were temporarily supported with heparin. In the 24-hour post-procedure period, they were given 10,000 IU of heparin and NOAC therapy was resumed the following day. In the other 135 patients, NOAC therapy was not interrupted, but during the catheterization period, they were switched to dabigatran (the so-called dabigatran bridge). Dabigatran therapy (110 mg twice daily) was started the day before catheterization and continued for 3 days after the procedure. Patients were then switched back to the original medication.

Course of Catheterization and Patient Monitoring Methods

All patients underwent transesophageal echocardiography before the procedure to exclude the presence of thrombi in the left atrium and to map the anatomy of the pulmonary veins. The procedure itself was performed under analgesic sedation using dexmedetomidine. After venous access was established, a bolus of 5000 IU of heparin was administered, followed by heparinized saline infusions to maintain the activated clotting time (ACT) between 300–350 seconds. Transseptal puncture and isolation of the pulmonary veins were performed. After 3–5 days of hospitalization, patients were discharged to home treatment and subsequently attended follow-ups every month for 3 months post-catheterization. Anticoagulant therapy continued for at least another 2 months after the procedure.

The efficacy and safety of both treatment methods were evaluated based on the incidence of complications and adverse events, especially cerebrovascular events, systemic embolizations, transient ischemic attacks, and bleeding events, during the catheter ablation and in the 8-week post-procedure period.

Results

The aforementioned adverse complications occurred in 8 out of 137 patients with interrupted NOAC therapy and in 8 out of 135 patients with uninterrupted NOAC therapy using dabigatran. Thus, the incidence of complications was comparable in both groups (8/137 vs. 8/135, p = 0.96). In the group with interrupted NOAC therapy, 1 patient suffered a stroke. Cardiac tamponade occurred in 1 patient in the uninterrupted NOAC therapy group, and specific antidote treatment was used.

Discussion

The study did not show any significant difference in the incidence of complications between the two monitored groups, despite the fact that patients with the dabigatran bridging therapy were significantly older.

In clinical practice, an increasing number of patients undergoing catheter ablation for AF are using NOACs, often direct factor Xa inhibitors. The use of the dabigatran bridge has several advantages compared to other anticoagulant protocols. The RE-CIRCUIT study confirmed a lower risk of bleeding events with dabigatran than with warfarin therapy. At the time from which the data used in this study were taken, dabigatran was the only NOAC for which a specific antidote could be used in case of severe bleeding.

Conclusion

Uninterrupted NOAC therapy with a temporary switch to dabigatran is a feasible option and may be suitable for minimizing the risk of thromboembolic complications in patients with atrial fibrillation undergoing catheter ablation, while ensuring optimal safety.

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Source: Daisetsu A., Shinsuke M., Kanae H. Feasibility of uninterrupted direct oral anticoagulants with temporary switching to dabigatran ("dabigatran bridge") for catheter ablation of atrial fibrillation. Int Heart J 2019 Nov 30; 60 (6): 1315−1320, doi: 10.1536/ihj.19-143.