Transoesophageal echocardiography: technique and indications
THE CONTEXT
Transoesophageal echocardiography (TOE) provides high-resolution images of cardiac and adjacent structures that may be poorly seen by transthoracic echocardiography.
Technique and visualisation
•
An endoscope-like ultrasound probe is passed into the oesophagus and upper stomach under light sedation and positioned behind the left atrium.
•
TOE is particularly useful for imaging the left atrial appendage, pulmonary veins, thoracic aorta and interatrial septum.
•
These structures may be poorly visualised by transthoracic echocardiography, especially in patients who are overweight or have obstructive airways disease.
Clinical indications
•
High-resolution imaging makes TOE particularly valuable for evaluating prosthetic valve dysfunction, especially involving the mitral valve.
•
Other indications include congenital abnormalities such as atrial septal defects and aortic dissection.
•
In infective endocarditis, TOE can detect vegetations too small to be detected by transthoracic echocardiography.
•
In patients with systemic embolism, TOE can investigate intracardiac thrombus or masses.