Embolic stroke after unanticoagulated cardioversion despite prior exclusion of atrial thrombi by transoesophageal echocardiography.

Recent studies in patients with atrial fibrillation, not on anticoagulation, suggest that if transoesophageal echocardiography (TEE) excludes the presence of thrombi, early cardioversion can be performed safely without the need for anticoagulation before the procedure. Immediately after successful cardioversion, however, left atrium or left atrial appendage stunning may be present, potentially carrying a risk for de novo thrombus formation. Furthermore, the presence of spontaneous contrast is considered as a contraindication for unanticoagulated cardioversion since it has been associated with postcardioversion thromboembolism. We present a case in which stroke developed in relation to unanticoagulated cardioversion regardless of careful prior evaluation with TEE.