Introduction Atrial Fibrillation (AF) management may include rate- or rhythm-control, and stroke prevention using anticoagulants. Restoration of sinus rhythm (SR) may be achieved by direct current cardioversion (DCCV). Safe DCCV requires at least 4 weeks of therapeutic anticoagulation before and after the procedure to minimise the risk of embolic stroke.. Warfarin has been the oral anticoagulant of choice for many years, but warfarin effects are unpredictable and there is a narrow therapeutic window, hence the need to monitor patient’s blood using INR testing. As a result patients may attend for DCCV without an adequate anticoagulation history.

This leads to procedure cancellations and treatment delay, lengthening of the DCCV waiting list at an increased cost to the hospital.It is also inconvenient for the patient and potentially could cause adverse atrial and ventricular remodelling as a result of prolonged time in AF.

Aims To determine the frequency and cost of DCCV cancellations due to inadequate anticoagulation.

Method We performed a retrospective analysis of the outpatient DCCV service in this hospital from August 2012 to August 2013.

Results 138 patients were listed for DCCV from August 2012 to August 2013. There were 40 (29%) cancellations.Of the cancelled patients, 22 (55%) were due to sub-therapeutic INR and 2 patients (5%) were not yet started on warfarin when they attended the pre-assessment clinic.All 24 were relisted.In addition 6 patients (15%) were back in SR prior to DCCV, 3 patients (7.5%) declined the procedure, 2 patients (5%) were deferred because of gastrointestinal bleeding, 1 patient was cancelled due to poorly controlled hypertension requiring hospital admission. 2 patients had bradycardia, of which 1 was listed for permanent pacemaker implantation.1 patient was done privately, and 1 patient was cancelled due to unspecified reason. The calculated local cost for DCCV listing is £202 per patient. The total cost of the 40 cancellations was therefore £8080, of which the cost of the 24 cancellations due to warfarin-related issues was £4848.It would cost £151.20 to anticoagulate 1 patient with dabigatran for 1 month either side of DCCV and this would have avoided 24 cancellations.This would translate into a saving of £1117 during the study period. Furthermore, a prolonged period of AF due to cancellation related to anticoagulation issues potentially has an adverse impact on cardiac function and patient outcome.

Conclusions The cancellation rate of DCCV in this hospital is high and is costly. 29% of the procedures were cancelled during the study period, of which more than two thirds were related to anticoagulation problems, which may be preventable. Replacing warfarin with a novel oral anticoagulant such as dabigatran with a predictable anticoagulation effect appears to be useful and cost effective.