Transesophageal Echocardiographic Evaluation for Potential Sources of Embolism in the Patients with Ischemic Stroke

ABSTRACT

BACKGROUND: It has been reported that about one-sixth of all cerebral infarcts are due to cerebral embolism of cardic origin. But transthoracic echocardiographic examination(TTE) of patients with embolic strokes has made low yield for identifying the cause of cardiac or extracardiac source of embolism. Recently, transesophageal echocardiography(TEE) has been proved to be more sensitive than TTE for that purpose. We have studied to detect the potential sources of embolism and to asess the diagnostic yield of TEE in the patient with ischemic strokes. METHOD: Thirty-nine patients with recent cerebral ischemic events(19 men, 20 women, mean age 61), and thirty-eight control patients with other cardiac disease(14 men, 24 women, mean age 52) were examined by both TTE and biplane TEE. For detection of patent foramen ovale, transesophageal contrast echocardiography using 10 ml of agitated saline was performed in all patients. Thoracic aorta, arch of aorta, and ascending aorta were examined during pull back of esophageal probe. RESULTS: 1) TEE is superior to TTE for detection of potential sources pf embolism in the ischemic stroke patients(82 vs 21%, p < 0.001). 2) The potential sources of embolism diagnosed by TEE in the ischemic stroke patients were as follows 18 aortic atherosclerotic plaque or clot, 11 left atrial(LA) spontaneous echo contrast, 8 LA appendage thrombus, 6 LA thrombus, 6 atrial septal aneurysm, 6 mitral stenosis, 3 patent foramen ovale and 1 prosthetic valve. 3) TEE is the unique procedure to diagnose aortic lesions, LA spontaneous echo contrast, atrial septal aneurysm and patent foramen ovale. 4) The incidence of the aortic lesions by TEE is significantly higher in the patients with ischemic stroke than in the controls(46 vs 11%, p < 0.01). CONCLUSION: Transesophageal echocardiography is useful for detection of potential cardiac and extracardiac sources of embolism compared with TTE and is a unique method for diagnosing aortic atherosclerotic lesion, left atrial spontaneous echo contrast, atrial septal aneutysm, patent foramen ovale and small left atrial appendage thrombus.