TRANSESOPHAGEAL ECHOCARDIOGRAPHY IN UNSELECTED PATIENTS WITH FOCAL CEREBRAL-ISCHEMIA - WHEN IS IT USEFUL

Although transesophageal echocardiography (TEE) has been shown to be m ore sensitive than transthoracic echocardiography (TTE) in detecting c ardioembolic abnormalities, it remains unclear which patients with acu te focal cerebral ischemia specifically benefit from TEE, We therefore performed TEE and TTE with color flow Doppler studies prospectively i n 109 unselected patients presenting with cerebral infarcts (n = 63) o r transient ischemic attacks (TIA; n = 46) from one acute stroke unit and clinical stroke service at a large urban hospital to determine whi ch cardiac abnormalities increase or decrease the yield of TEE for det ecting potential causes of focal cerebral ischemia. Paired echocardiog raphic studies were performed during the same testing period in 107 pa tients (2 patients with left ventricular thrombus did Trot go on to ha ve TTE). TEE detected more left atrial thrombi and spontaneous atrial contrast than TTE (12 vs. 4, p = 0.032, and 10 vs. 1, p < 0.002). TEE also demonstrated atheromatous changes in the ascending and/or descend ing thoracic aorta of 7 patients, compared to 1 by the transthoracic s tudy (p = 0.008). Furthermore, a patent foramen ovale with or without septal aneurysms was more frequently found by TEE compared to TTE. Of the 15 patients with left or right atrial thrombi, 12 (80%) had corres ponding enlarged atria on TTE, and 9 (60%) had concomitant atrial fibr illation. Left atrial thrombi and smoke occurred in significantly fewe r(p less than or equal to 0.001) patients with normal left atria compa red to those with dilated atria. The same was true for patients in sin us rhythm compared to atrial fibrillation. In patients with focal cere bral ischemia, TEE is superior to TTE in demonstrating atrial thrombi and spontaneous atrial contrast echoes but not left ventricular thromb i. The diagnostic yield of TEE to demonstrate atrial thrombi is signif icantly higher in patients with dilated atria and atrial fibrillation. TEE should be performed in all ischemic stroke or TIA patients if the y have a dilated left atrium and/or atrial fibrillation and if discove ry of a thrombus would alter therapy. This test should only be conside red in patients with sinus rhythm and/or normal atria if all other inv estigative studies for noncardiac sources of cerebral emboli are nondi agnostic.