Dabigatran Improves the Efficiency of an Elective Direct Current Cardioversion Service

Wai Kah Choo, Shona Fraser, Gareth Padfield, Gordon F Rushworth, Charlie Bloe, Peter Forsyth, Stephen J Cross, Stephen J Leslie


Br J Cardiol. 2014;21(1):29-32. 

In This Article

Abstract and Introduction


Anticoagulation prior to direct current cardioversion (DCCV) is mandatory to reduce the risk of thromboembolism. We examined the impact of the use of dabigatran as an alternative to warfarin on the efficiency of an outpatient DCCV service. A total of 242 DCCVs performed on 193 patients over a 36-month period were analysed. Patients were divided into two cohorts; cohort A included cases in the 22-month period before the introduction of dabigatran and cohort B included cases in the 14-month period after the introduction of dabigatran. All patients in cohort A received warfarin. In cohort B, 48.4% received dabigatran. A larger number of patients from cohort A were rescheduled due to subtherapeutic international normalised ratios (INRs) compared with cohort B (42.1% vs. 15.6%, p<0.001). Those who received dabigatran had significantly lower rates of rescheduling compared with those who received warfarin (9.7% vs. 34.4%, p<0.001). The length of time between initial assessment and DCCV was 24 days shorter in cohort B than cohort A (p<0.001) and 22 days shorter with those who took dabigatran than warfarin (p=0.0015). Outcomes in achieving and maintaining sinus rhythm were comparable in both cohorts and anticoagulants (all p>0.05). This study demonstrates that the use of dabigatran can improve the efficiency of an elective DCCV service.


Atrial fibrillation (AF) is a common arrhythmia affecting approximately 1% of the general population, this rises to 18% in those aged 85 years and above.[1] The most effective method for correcting persistent AF is direct current cardioversion (DCCV). However, DCCV is associated with an increased risk of thromboembolic events.[2] Anticoagulation with warfarin reduces the risk of thromboembolism from approximately 6% to less than 1%.[3]

The current recommendations advise therapeutic anticoagulation for at least three weeks prior to, and four weeks after cardioversion.[4] A nurse-led elective DCCV service at Raigmore Hospital was established in 2006 and, initially, warfarin was the only anticoagulant available. Frequent subtherapeutic international normalised ratios (INRs) resulted in the cancellation and rescheduling of many DCCV appointments, often at short notice, disrupting clinical services and patient care.

The new oral anticoagulant dabigatran, which became available recently, has been shown to be at least as effective as warfarin in preventing stroke in patients with AF.[2,5] Dabigatran is a direct thrombin inhibitor with rapid onset of action, achieving peak plasma concentration within 30 minutes to two hours of administration, and patients do not require therapeutic INR level monitoring. From December 2011, we used dabigatran as an alternative to warfarin in suitable patients undergoing DCCV. We aimed to examine the impact of the use of dabigatran as an alternative to warfarin on our DCCV service.