Intracardiac pathology results in 15 - 20% of ischemic stroke, but transthoracic echocardiography (TTE) has a number of limitations because of suboptimal precordial windows or ultrasound interference with prosthetic materials. Transesophageal echocardiography (TEE) provides superior resolution of basal structures such as the left atrium, left atrial appendage, mitral valvular apparatus, atrial septum, and aorta. The purpose of this study was to describe the various TEE findings which were sources of cerebral emboli.

The study population was comprised of 122 patients (mean age:54.5, male 83, female 39) who were admitted to Severance Hospital because of ischemic stroke from 1991 to 1997. All patients underwent TEE with agitated saline contrast administration. Patients without a definitive cardiac source of embolism underwent Holtor monitoring, internal carotid and cerebral angiography, as well as transcranial Do-ppler.

1) The number of patients diagnosed as cardioembolic stroke was 55 (45.1%). Atrial fibrillation was noted in 31 patients of cardioembolic stroke and it was the most frequent finding. Among these patients, 16 did not have any other cardiac problem. 2) We were able to find the possible source of embolism in 49 (40.2%) patients with TEE. Among these patients, 12 did not have dysrhythmia or any known previous heart problem. We found spontaneous echo contrast in the left atrium and left atrial appendage in 33 cases. There were 8 patients who had intracardiac thrombus. Among these patients, 6 patients had thrombi in the left atrial appendage, 1 in left atrium and 1 in left ventricular apex. We found patent foramen ovale in 3 cases and atrial aneurysm in 1 case. We found atheromatous plaque and/or thrombi of the aorta in 16 cases, while there were 4 cases where lesions located in the ascending aorta and aortic arch and which were considered as the source of embolism. Small thrombi in the left atrial appendage and left atrium were only detectable with TEE.

We described TEE findings in ischemic stroke patients. And we assert TEE is a useful diagnostic tool in detecting the source of cardioembolic stroke and it may be used as a primary diagnostic tool in patients who are being evaluated for ischemic stroke.