Is onemonth treatment with dabigatran before cardioversion of atrial fibrillation sufficient to prevent thromboembolism?

Abstract

Aims: The use of direct oral anticoagulants (DOACs) in patients undergoing elective direct current (DC) cardioversion of nonacute atrial fibrillation (AF) can potentially shorten the time frominitiation of anticoagulation treatment to cardioversion, compared with warfarin. The safety of this strategy needs to be investigated. Data from subgroup analysis from clinical trials with DOAC do not clarify whether 4-week treatment with DOAC is sufficient to prevent thromboembolism (TE) after cardioversion. The aim of this retrospective study was to assess the incidence of TE in anticoagulant naive patients converted after one month's pre-treatment with dabigatran. Methods and results: We scrutinized the medical records of 631 patients where dabigatran had been used prior to elective DCcardioversion. Transoesophageal echocardiography was rarely performed. Thromboembolism within 30 days of cardioversionwas the primary endpoint. A total of 570 patients were naive to OAC when dabigatran was initiated. The mean age in this groupwas 64.2+11 years and 31.7%werewomen.ThemeanCHA2DS2-VASc scorewas 2.0+1.5.The dose of dabigatranwas 150 mg b.i.d. in 94% of the patients. The median time frominitiation of dabigatran to cardioversion was 32.0+15 days. In91% cardioversion resulted in sinus rhythm. During the 30-day follow-up, three TE occurred for an incidence of 0.53% (0.18-1.54). Conclusion: In this retrospective study from clinical material, we found a lowincidence of TE when dabigatranwas used as TE prophylaxis in association with elective cardioversion. These results indicate that dabigatran is a safe alternative strategy towarfarin during cardioversion in patients with AF.