Conversion of atrial fibrillation to sinus rhythm: a possible side effect of transesophageal echocardiography.

Transesophageal echocardiography (TEE) is accepted as the procedure of choice for the diagnosis of intracardiac sources of systemic embolism. A case report is presented on a 74-year-old patient with atrial fibrillation referred for TEE evaluation after an acute embolic event. During TEE, atrial fibrillation converted to sinus rhythm. Although TEE is a very safe method, which is performed in increasing numbers of patients, this is the first reported case of conversion of atrial fibrillation to sinus rhythm during the procedure. We suggest that no restriction should be imposed on the use of TEE in patients with atrial fibrillation, as the small risk associated with conversion of atrial fibrillation is outweighed by the potential diagnostic benefits.