Synchronized direct current cardioversion (CV) is a common treatment for atrial fibrillation (AF) if primary treatment with anti-arrhythmic drugs fails. However, direct current CV, without pretreatment precautions, is associated with an increased risk of embolic stroke, presumably due to dislodgement of intracardiac thrombi. In order to prevent such complications, patients are typically treated with systemic anticoagulants for at least 3 weeks prior to cardioversion. (1) Warfarin has historically been the standard for anticoagulant treatment in AF. Warfarin reduces the risk of embolic stroke by 66% in AF patients. In addition, warfarin is relatively inexpensive and unaffected by renal function, which makes it a popular anticoagulant drug. (2) Direct oral anticoagulants (DOACs such as apixaban, dabigatran, rivaroxaban and edoxaban) are becoming more prevalent in use. DOACs directly inhibit clotting factors instead of targeting Vitamin K as warfarin does. Apixaban, rivaroxaban and edoxaban are reversible inhibitors of Factor Xa. Dabigatran is a reversible inhibitor of thrombin. DOACs are being increasingly used in place of warfarin to prevent embolic stroke in AF but there is limited data on their efficacy and safety in the setting of elective CV for AF, particularly compared to warfarin.
Our hypothesis was that DOACs are not inferior to warfarin in preventing adverse events and recurrent AF following elective CV. To test this, we analyzed 30-day outcomes from an ongoing three-year outpatient CV registry. We sought to determine the following objectives:
• The rate of adverse events within 30 days following all cardioversions on patients treated with warfarin vs. DOACs.
• The rate of AF recurrence within 30 days post-cardioversion in patients on warfarin vs. DOACs
Keltner, Emily BS, MA; Wong, Charles; Davis, Christopher; Baker, Aaron BA; and Wilson, William, "Elective Direct Current Cardioversion for Patients with Atrial Fibrillation: A Registry Analysis of Adverse Events and Recurrence" (2017). Parkview Heart Institute. 14.