Adherence to oral anticoagulant treatment and risk factor assessment six months after DC-conversion of atrial fibrillation

Abstract

Objective. We wanted to study the adherence of oral anticoagulant treatment in patients 6 months after elective DC-cardioversion and to observe possible increases in CHA2DS2-VASc scores and new adverse outcomes. Design. Consecutive patients admitted for elective DC-cardioversion at Haukeland University Hospital during the period from June 2017 to April 2018 were screened. Only patients who had a DC-cardioversion performed were included. Baseline information was collected from hospital records and follow up information was gathered through a structured phone interview and the prescription database. Results. Of the 125 patients screened, 38 were excluded as DC-cardioversion was not performed. The included patients were contacted 6 months later, out of whom 77 (84%) responded. Three patients had discontinued oral anticoagulation therapy, but only one patient had done so in violation of Guidelines. Two patients had continued oral anticoagulant treatment despite lack of indication. Of the responding patients 89% were compliant, estimated by a Proportion of Days Covered > 80%. Three patients experienced a thromboembolic event, despite being on anticoagulation. The mean CHA2DS2-VASc score increased from 3.0 ± 1.4 to 3.3 ± 1.5, (p < .001). Less than half maintained sinus rhythm, the remaining had either atrial fibrillation (n = 30, 40%) or were unsure of their current rhythm (n = 9, 12%). A third received new cardiac interventions during follow up. Conclusion. We found an excellent adherence to Guidelines recommended therapy amongst our patients. CHA2DS2-VASc scores increased significantly during the 6-month observation period. From this we conclude there is a need for structured follow up to assess new risk factors.