Transesophageal echocardiography: procedures and clinical application.

In existence for more than a decade, transesophageal echocardiography has gained renewed interest because of technologic advances including high resolution transducers, multiple imaging planes and Doppler color flow mapping. The heart is imaged from within the esophagus with a gastroscope-mounted transducer, obviating technical difficulties encountered in transthoracic echocardiography. Transesophageal echocardiography is utilized intraoperatively to monitor patients undergoing open heart surgery or high risk cardiac patients undergoing noncardiac surgery. In the ambulatory patient, the procedure facilitates imaging of many structures (including the left atrium and appendage, mitral and aortic native and prosthetic valves and thoracic aorta), with better resolution than that obtained by routine transthoracic echocardiography. Technical aspects of transesophageal echocardiography as well as its indications and limitations are reviewed.