Randomized Comparison of Continuous Versus Intermittent Heparin Infusion During Catheter Ablation of Atrial Fibrillation

Abstract

Objectives: This study tested the hypothesis that continuous heparin infusions would be favorable for maintaining heparin concentrations during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).

Background: Heparin infusions are essential for RFCA of AF. There is a paucity of data on the details for the optimal heparin infusion during RFCA of AF.

Methods: A total of 333 patients undergoing AF ablation were consecutively enrolled and randomized to intermittent or continuous heparin infusion. A heparin bolus of 100 U/kg was injected just prior to transseptal puncture. The heparin concentration necessary to maintain an optimal activated clotting time (ACT) (300 to 400 s) was determined and checked every 30 min during the procedure. The primary endpoint of the study was the frequency of the maintenance of an optimal intraprocedural ACT.

Results: The frequency of an optimal ACT in the continuous group was significantly higher than that in the intermittent group (64.0% vs. 57.6%, respectively, p < 0.01), whereas the total heparin level was significantly lower in the continuous group (13,162 ± 4,634 U vs. 15,837 ± 5,243 U, respectively, p < 0.01). The standard deviation of the ACT was significantly smaller in the continuous group than in the intermittent group (49 ± 30 vs. 33 ± 18, respectively, p < 0.01). Ninety-six patients had new oral anticoagulants (NOACs) before the procedure, and an optimal ACT at the first ACT check was less frequent than in patients taking warfarin (12.5% vs. 59.1%, respectively, p < 0.01). There were no significant differences in periprocedural bleeding or thromboembolic complications between the groups.

Conclusions: During AF ablation, a continuous heparin infusion was superior to an intermittent heparin infusion for maintaining an optimal ACT range. (Randomized Comparison of Continuous and Intermittent Heparin Infusion During Catheter Ablation of Atrial Fibrillation [COHERE]; NCT01935557).

Keywords: activated clotting time; anticoagulants; atrial fibrillation; catheter ablation; heparin.