Left Atrial Appendage Thrombosis during Therapy with Rivaroxaban in Elective Cardioversion for Permanent Atrial Fibrillation

Electric external cardioversion (EEC) for permanent atrial fibrillation (AF) carries a risk of thromboembolic events (TE). The use of transesophageal echocardiography (TEE) to guide the management of atrial fibrillation may be considered a clinically effective alternative strategy to conventional therapy for patients in whom elective cardioversion is planned. Therapeutic anticoagulation with novel oral anticoagulants (NOAC) is recommended for 3 to 4 weeks before and an anticoagulation life-long therapy is recommended after EEC to reduce TE, in patients with high CHA₂DS₂-VASc score; however, only few data are currently available about safety of shortterm anticoagulation with NOAC in the setting of EEC. Patients with increased risk of thromboembolism have not been adequately studied and the monitoring of anticoagulant effects can also have important benefits in case of drug interactions. We report a case of a 68-year old man with AF from September 2014. Moderate depression of global left ventricular systolic function was detected by echocardiographic exam. On the basis of a high thromboembolic risk, an anticoagulant therapy with rivaroxaban, at the dose of 20 mg/day, was started. TEE showed a thrombus in the left atrial appendage. This case demonstrates the utility of performing TEE prior than EEC in patients with hypokinetic cardiomyopathy other than AF in therapy with NOAC. We underline the presence of significant pharmacodynamic interference of rivaroxaban with other drugs such as oxcarbazepine.