Protocol driven periprocedural anticoagulation for left atrial ablation

Abstract

Introduction A weight‐based heparin dosing policy adjusted for preprocedural oral anticoagulation was implemented to reduce the likelihood of subtherapeutic dosing during left atrial catheter ablation procedures. We hypothesized that initiation of the protocol would result in a greater prevalence of therapeutic activated clotting time (ACT) values and decreased time to therapeutic ACT during left atrial ablation procedures. Methods A departmental protocol was initiated for which subjects received intravenous unfractionated heparin (UFH) to achieve and maintain a goal of ACT >300 s. Initial bolus dose was adjusted for pre‐procedure oral anticoagulation and weight as follows: 50 units/kg for those receiving warfarin, 75 units/kg for those not anticoagulated, and 120 units/kg for those on direct oral anticoagulants (DOACs). A UFH infusion was initiated at 10% of the bolus per hour. One hundred consecutive left atrial ablation procedures treated with Protocol Guided heparin dosing were compared with a retrospective consecutive cohort of Usual Care heparin dosing. Results When the Usual Care and Protocol Guided cohorts were compared, significant findings were limited to those on pre‐procedure DOAC. The initial UFH bolus increased from 99.3 ± 24.8 to 118.2 ± 22.8 units/kg (p < .001), the proportion of therapeutic ACT on the first draw after heparin administration increased from 57.7% to 76.6% (p = .010), and the time to therapeutic ACT after UFH administration decreased from 37.8 ± 19.8 to 30.2 ± 16.4 min (p = .032). Conclusion A weight‐based protocol for periprocedural UFH administration resulted in a higher proportion of therapeutic ACT values and decreased the time to therapeutic ACT for those on pre‐procedure DOAC.

Evaluation of an adaptive, rule-based dosing algorithm to maintain therapeutic anticoagulation during atrial fibrillation ablation

“…The sample size is similar to other published reports but does limit the results. 14 , 15 , 16 , 17 The number of patients on each of the 4 preprocedural oral anticoagulants studied here is small—especially dabigatran—making the results less generalizable. When the ACT did drop below goal, the time below goal did decrease using the algorithm, but it was not a statistically significant decrease.…”

“…In 89 patients on NOACs, Payne and colleagues 14 found that 29% of ACTs were therapeutic when using an initial bolus of 120 U/kg and increased to 49% when the initial bolus was increased to 150 U/kg. Bradley and colleagues 16 reported that a protocol-guided approach that accounted for preprocedure oral anticoagulant and weight-based dosing did increase the proportion of therapeutic ACT on first draw to 76.6%, from 57.7%, and decreased the average time to therapeutic ACT to 30 minutes; however, supratherapeutic ACT on first draw (>400 seconds) increased from 6.4% to 18.2%. Safani and colleagues 17 reported impressive results using a comprehensive weight-adjusted, weight-based protocol that demonstrated a time to ACT >300 seconds of 14.6 minutes in 99 patients on NOACs.…”

“… 25 However, a task like heparin dosing in the electrophysiology lab lends itself to a computer-based CDSS, as most published guidance and protocols require repeated measurements and calculations that take into account specific patient characteristics like weight and anticoagulant type. 2 , 15 , 16 , 17 The work here demonstrates a beginning, but there are limitations to be addressed and future work to be done to refine the tool.…”

“…Others have reported on similar knowledge gaps in catheter ablation for AF: (1) difficulty achieving therapeutic ACT, especially with NOACs; (2) practice variation among individual providers; and (3) lack of protocols to deliver intraprocedural anticoagulation. 14 , 15 , 16 , 17 The protocols described in these prior reports did not include a computer-based clinical decision support system (CDSS).…”