A Retrospective Study on the Use of Direct Oral Anticoagulants in Atrial Fibrillation Patients at Cardiac Outpatient Setting, Sarawak Heart Centre

Abstract

Introduction:

Atrial fibrillation (AF) increases stroke risk up to five-fold, but anticoagulants have been shown to reduce that risk. Compliance with direct oral anticoagulants (DOAC) improved thromboembolic outcomes and was superior to warfarin in decreasing all-cause mortality. This study evaluated the compliance with the CHA2DS2VASc scoring system for DOAC prescribing, the pre-initiation, and post-initiation monitoring practices, and the pattern of use of DOAC in AF patients undergoing follow-ups at the Cardiac Clinic of Sarawak Heart Centre.

Methods:

This retrospective study involved 55 eligible AF patients undergoing follow-ups at the Cardiac Clinic of Sarawak Heart Centre between 1st January 2020 and 30th June 2021.

Results:

Based on the CHA2DS2VASc scoring system, most of the participants were indicated for DOAC as per guidelines, [male (n=26, 72.2%); female: (n=15, 78.9%)]. Before DOAC initiation, liver functions tests (n=32, 58.2%) were absent in most monitoring parameters, which was then followed by the absence of renal function tests (n=11, 20.0%) and coagulation profiles (n=22, 40.0%). For routine post-initiation monitoring, 15 patients (27.3%) did not have their renal profile repeated within one year of post-DOAC initiation. In terms of the pattern of use, Dabigatran 150mg was more commonly initiated in patients below 80 years old (n=29, 59.2%) and those with a Creatine Clearance (CrCl) of 50 mL/min or higher (n=22, 64.7%). On the other hand, Dabigatran 110mg was preferred for patients aged 80 years and above (n=4, 66.7%) and those with a CrCl ranging from 15 mL/min to 49 mL/min (n=5, 50.0%).

Conclusion:

Prescribers adhered to the CHA2DS2VASc scoring system when initiating DOAC. Age and creatinine clearance were considered before the initiation of DOAC. Complete monitoring, including renal function tests, liver function tests, and coagulation profiles is crucial before and after initiating DOAC therapy to ensure effectiveness, safety, and appropriate selection of DOAC.