Abstract
Cardioembolism accounts for 20-25 % of ischemic strokes. Transthoracic echocardiography (TTE) can detect potential cardiac source of embolism in left atrium, on mitral or aortic valve (thrombi, myxoma, vegetation) or detect mitral valve disease.
It is well recognized that rheumatic valvular heart disease is a risk factor for stroke. Left ventricular dysfunction, when severe, can lead to thromboembolism and stasis of blood flow within the heart.
Transesophageal echocardiography (TEE) is more sensitive than TTE in the detection of potential cardiogenic sources of emboli. The sensitivity is nearly 100% in detecting left atrial thrombi, spontaneous echo contrast, atrial septal aneurysm, interatrial shunts supportive of a possible paradoxical cerebral embolus, ventricular thrombi or aneurysm.
TEE is reported to reveal a left atrial appendage thrombus in roughly 10 % of patients with nonvalvular atrial fibrillation and in 20 to 40 % of patients with recent thromboembolism. It is reported a significantly higher prevalence of patent foramen ovale in patients with ischemic stroke who were younger than 55 years of age.
In detecting left atrial thrombi, spontaneous echo contrast, atrial septal aneurysm, interatrial shunts supportive of a possible paradoxical cerebral embolus, ventricular thrombi or aneurysm, or myxomatous mitral valve was 8 % when transthoracic echocardiography was performed and 46 % when transesophageal echocardiography was performed. The echocardiographic finding can decide in a fundamental way on the indication for anticoagulation treatment and thus reduce the risk of relapse of stroke.