[When should transesophageal echography be ordered?].

Abstract

The exceptional quality of cardiac imaging, access to otherwise inaccessible anatomic areas and optimal alignment on anatomic structures make transoesophageal echography an exceptional high performance imaging technique. But when should it be ordered? Suspected aortic dissection is a major indication for transoesophageal echography. Diagnosis can be confirmed with sensitivity and specificity of 95 to 99%. The performance of the transoesophageal route is also better than that of the transthoracic route in case of suspected infectious endocarditis and should be ordered when the transthoracic image is insufficient, a perivalvular abscess is suspected, fever persists, infection on a prosthesis is suspected, blood cultures are negative or heart failure compromises cardiac performance. It should be remembered however, that a normal transoesophageal echography cannot eliminate the diagnosis of infectious endocarditis. The method is however extremely useful for close follow-up of endocarditis. Thrombo-embolic events with neurological or peripheral expression are also frequent indications for transoesophageal echography. Three direct causes can be detected: thrombus in the left atrium, contrast in the left atrium corresponding to micro-platelet aggregation due to prolonged stasis and intra-aortic debris. Septal anomalies may indicate an indirect cause. Aortic or mitral valvulopathies are another area of importance because transoesophageal echography results are well correlated with haemodynamic performance. Patients with a poorly tolerated mitral regurgitation with or without criteria of gravity could benefit from transoesophageal echography. Valve prostheses, especially mitral prosthesis, are also important indications. Per-operative examinations are particularly important for evaluating valve replacement quality after cardiac circulation has been reestablished. In addition, the high quality of transoesophageal images is particularly useful in investigating congenital cardiopathies and in certain intensive care patients.