Apixaban equally safe as warfarin for anticoagulation during AFib ablation

Continuous anticoagulation with apixaban during atrial fibrillation (AFib) ablation was found to be as safe as warfarin and other vitamin K antagonists (VKAs) in a randomized trial of 633 patients.

The trial, presented March 20 at the European Heart Rhythm Association congress in Barcelona and published simultaneously in the European Heart Journal, was the first to test apixaban (Eliquis) in this setting.

The composite endpoint of death, stroke and major bleeding occurred in 22 of 318 patients randomized to apixaban and 23 of 315 taking VKAs, a nonsignificant difference. In addition, the researchers noted an improvement in cognitive function after ablation regardless of which anticoagulant was used.

“This is the first randomized trial to show that cognitive function is improving after atrial fibrillation ablation,” chief investigator Paulus Kirchhof, MD, said in a press release. “It is possible that this is due to continuous anticoagulation, although we did not test this specifically.”

A substudy of 335 of the patients who received brain MRIs within 48 hours of ablation revealed 27.2 percent of patients randomized to apixaban and 24.8 percent of patients taking VKAs had evidence of acute brain lesions (silent strokes).

“Continuous anticoagulation does not fully prevent acute brain lesions, which can be caused by debris dislodging from ablation wounds, air emboli, or small thrombi,” the authors wrote. “Procedural improvements are desirable to reduce acute brain lesions during atrial fibrillation ablation.”

Apixaban is a Factor Xa inhibitor and a non-vitamin K antagonist oral anticoagulant (NOAC). AFib patients are recommended for NOACs over VKAs by the European Society of Cardiology except in those with a mechanical heart valve or rheumatic mitral valve stenosis, according to the press release.

Other NOACs such as dabigatran and rivaroxaban have been tested in the setting of ablation. One notable difference of this trial, the authors noted, is the patient population was four years older on average (median age 64; 33 percent female) than in studies of the other NOACs.

"The results of this trial will go a long way towards reassuring clinicians that continuous apixaban is a safe and effective alternative to VKA for patients undergoing atrial fibrillation ablation, even those at risk of stroke,” Kirchhof wrote.