Usefulness of an isoproterenol infusion to differentiate a left atrial appendage thrombus in a patient with nonvalvular atrial fibrillation.

A 78-year-old male with a history of a cardiac embolic stroke due to persistent AF and cerebral bleeding (CHADS2 score 4, HAS-BLED score 4) was referred to our hospital to implant a left atrial appendage (LAA) closure (LAAC) device. A trans esophageal echocardiography was performed and a high echoic lesion that was difficult to differentiate the spontaneous echo contrast or thrombus was found in the LAA cavity. After isoproterenol infusion, a high echoic lesion disappeared and we confirmed that it was not an LAA thrombus. Successful LAAC device implantation was performed without any thromboembolic events.