Comprehensive Intraprocedural Unfractionated Heparin Protocol During Catheter Ablation of Atrial Fibrillation in the Presence of Direct Oral Anticoagulants and Wide Spectrum of Body Mass Index

Abstract

Introduction: Data on optimal dosing of unfractionated heparin (UFH) in the presence of a direct oral anticoagulant (DOAC) to achieve and maintain an activated clotting time (ACT) of ≥300 seconds during catheter ablation of atrial fibrillation (CA-AF) are limited and prevalence of obesity adds to the unpredictable response to UFH. Methods and Results: One hundred seventeen consecutive patients undergoing CA-AF were prospectively administered weight-adjusted, weight-based UFH using a pre-specified detailed protocol and retrospectively analyzed. Due to lack of distribution of UFH into muscle or adipose tissue and lower degree of vascularity in the latter compartment, each patient’s ideal and actual weights were used to determine the adjusted-weight for use in all UFH doses. A UFH bolus of 200 units/kg was administered intravenously followed by an infusion of 35 units/kg/hour. The mean age was 65 years, and 85 patients (72.6%) were male. The average body mass index (BMI) was 30 (range 18-50) kg/m2. After the initial UFH bolus dose, 99 patients (84.6%) achieved ACT ≥300 sec with a mean (± SD) of 380 ± 79 sec. The mean time to reach an ACT ≥300 in all patients was 14.6 ± 12.4 minutes. Among all measured ACT values, 423 (90.8%) were ≥300 seconds. These results were consistent within all BMI categories. There were no intraprocedural thrombotic or hemorrhagic complications. Two patients (1.7%) sustained groin vascular access site hematoma without subsequent intervention and 7 patients (6%) experienced minor oozing post-procedurally. Conclusions: Our comprehensive weight-adjusted, weight-based UFH protocol, during CA-AF in presence of a DOAC, rapidly achieved and maintained an effective ACT irrespective of BMI.