Transoesophageal echocardiography (TOE) is a new modality of cardiac investigation allowing examination of cardiac structures and anomalies previously inaccessible to ultrasound. TOE is performed under local anaesthesia after fasting the subject for more than 4 hours and after premedication when the patient is admitted to hospital. In the assessment of an ischaemic cerebral vascular accident, TOE may reveal potential sources of emboli such as intracavitary thrombi and tumours (left atrium and left atrial appendage), atherosclerosis of the aortic arch, vegetations. Certain indirect causes may also be more clearly identified: aneurysm of the interatrial septum, patent foramen ovale for which the causal relationship is more difficult to establish. Intra-atrial blood stasis ("spontaneous echo contrast") is perfectly analysed in the form of intra-atrial "smoke" observed in the presence of atrial dilatation, particularly in the presence of atrial fibrillation and mitral valve obstruction (mitral stenosis, valve prosthesis). The indication for TOE in this context is currently under evaluation, particularly in young patients. It is routinely indicated in patients with known heart disease when peripheral embolism is suspected, looking for intracavitary thrombosis, generally not seen on transthoracic echocardiography.