Right atrial appendage thrombus found in a patient in normal sinus rhythm with normal right ventricular systolic function.

A 79-year-old woman underwent transesophageal echocardiography to evaluate the severity of her mitral regurgitation prior to urgent bypass. Evaluation of the right-sided chambers was notable for a mass in the right atrial appendage (RAA). Surgical excision and pathologic examination proved this to be a thrombus. This is the first reported case of a RAA thrombus in a patient with normal sinus rhythm and normal right ventricular (RV) function. It illustrates that complete transesophageal studies may sometimes demonstrate incidental findings, and that right atrial thrombus can (rarely) be found in patients in sinus rhythm with normal RV function.