The incidence of left atrial appendage thrombi on transesophageal echocardiography after pretreatment with apixaban for cardioversion in the real-world practice

Abstract

The risk of thromboembolisms during the post-cardioversion period is high. For patients with persistent atrial fibrillation (AF), anticoagulation with warfarin (INR 2.0~3.0) is recommended for at least three weeks prior and four weeks after cardioversion. We aimed to evaluate the efficacy of apixaban in preventing thromboembolic events during post-cardioversion. We enrolled 127 consecutive persistent AF patients (83 persistent, 44 longstanding persistent AF), scheduled to undergo cardioversion and were pretreated with apixaban. All patients underwent transesophageal echocardiography (TEE) to rule out thrombi in the left atrium (LA) or LA appendage (LAA) after anticoagulation with apixaban. The median duration of anticoagulation before the TEE was 37 (interquartile range [IQR] 34, 50) days. There were 7 patients (5.5%) with visible thrombi in the LAA. A spontaneous echo contrast was noted in 24 (18.9%) patients. Cardioversion was attempted in 117 patients, and they were prescribed amiodarone before the elective DC cardioversion. Sinus rhythm was achieved in 37 patients (31.6%) by amiodarone itself. DC cardioversion was attempted in 80 patients and was successful in 73 (91.3%). None of the cardioverted patients had any thromboembolic events within one month. Transient ischemic attacks were observed in one patient during a median follow up period of 202 days (IQR 143, 294). In conclusion, apixaban could be used as an anticoagulant for patients scheduled for cardioversion. However, the incidence of thrombi was not negligible. TEE or other imaging modalities should be considered before cardioversion or other invasive procedures.