Uninterrupted DOACs Approach for Catheter Ablation of Atrial Fibrillation: Do DOACs Levels Matter?

Abstract

Most patients present for catheter ablation of atrial fibrillation (CAAF) with residual or full effect of vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs). In daily practice, it has been observed that the activated clotting time (ACT) was actually poorly sensitive to the effect of DOACs and that patients on DOACs required more unfractionated heparin (UFH) to achieve the ACT target of 300 s during the procedure, leading some authors to worry about potential overdosing. Conversely, we hypothesize that these higher doses of UFH are necessary to achieve adequate hemostasis during CAAF regardless of the residual effect of DOACs. During CAAF, thrombosis is promoted mainly by the presence of thrombogenic sheaths and catheters in the bloodstream. Preclinical data suggest that only high doses of DOACs are able to mitigate catheter-induced thrombin generation, whereas low dose UFH already do so. In addition, the effect of UFH seems to be lower in patients on DOACs, compared to patients on VKAs, explaining part of the differences observed in heparin requirements. Clinical studies could not identify increased bleeding risk in patients on DOACs compared to those on VKAs despite similar efficacy during CAAF procedures. Moreover, targeting a lower ACT was associated with an increased periprocedural thrombotic risk for both DOAC and VKA patients. Therefore, the low sensitivity of the ACT to the residual effect of DOACs should not be a major concern in its use in the interventional cardiology laboratory.

Safety and Efficacy of Uninterrupted Oral Anticoagulation in Patients Undergoing Catheter Ablation for Atrial Fibrillation with Different Techniques

“…We observed an incidence of 1.2% of major periprocedural complications represented by embolic events (one periprocedural ischemic stroke and one systemic air embolism). These data are consistent overall with other reports in the literature [4][5][6][7][8][9][10].…”

“…Overall, 65 patients were affected by structural heart disease, better defined as follows: ischemic cardiopathy (n = 25), valvular heart disease (n = 14), hypertensive cardiomyopathy (n = 13), non-ischemic dilated cardiomyopathy (n = 8), and high-rate AF-induced tachycardiomyopathy (n = 5). The CHA 2 DS 2 -VASc and HAS-BLED scores presented a median value of 2 [1][2][3][4] and 2 [1-2], respectively. The maximum CHA 2 DS 2 -VASc score was eight while the maximum HAS-BLED score recorded was five.…”

“…Most major frequent intra-and perioperative complications are either hemorrhagic or thromboembolic, such as vascular access bleeding, pericardial effusion, cardiac tamponade (in 1-3% of cases), TIA (transient ischemic attack), or stroke (1%). In order to minimize the procedure-related thromboembolic risks, it is necessary to maintain the patient on anticoagulant therapy before, during, and after the CA [4][5][6][7][8][9]. During the procedure, the required anticoagulation state is achieved by the administration of unfractionated heparin, ideally prior to or immediately following transseptal puncture, and adjusted to maintain a target activated clotting time (ACT) of 300 s or more.…”