Transesophageal echocardiography in the detection of potential cardiac source of embolism in stroke patients.

To compare the diagnostic yields of transesophageal and transthoracic echocardiography in the detection of potential cardiac sources of embolism, 63 patients (mean +/- SD age 63 +/- 15 [range 18-87] years) with transient ischemic attacks or stroke underwent both procedures. Transthoracic echocardiography revealed a potential cardiac source of embolism in 14% (nine) of the patients, all of whom had clinical evidence of heart disease. Transesophageal echocardiography revealed a potential cardiac source of embolism in 41% (26) of the patients; 27% (seven) of these patients had no clinical cardiovascular abnormalities. Abnormalities detected only by transesophageal echocardiography in the patients with unsuspected cardiac disease included atrial septal aneurysm in two, patent foramen ovale in two, left atrial appendage thrombus in one, and myxomatous mitral valve in two. The 26 patients with an identified cardiac source of embolism were older (67.5 versus 59.4 years, p = 0.04), more frequently in atrial fibrillation (62% [16] versus 8% [3], p less than 0.0001), had a larger left atrium (43 versus 37 mm, p = 0.01) and more commonly had left ventricular hypertrophy (62% [16] versus 32% [12], p less than 0.02) than the 37 patients in whom no cardiac source of embolism was identified. Thus, transesophageal echocardiography is more sensitive than transthoracic echocardiography in the detection of potential cardiac sources of embolism in patients with cerebral ischemic events.