Right-to-left-shunts detected by transesophageal echocardiography and transcranial Doppler sonography.

Background: Transesophageal echocardiography (TEE) and transcranial Doppler sonography (TCD) can identify right-to-left-shunts that predispose to paradoxical embolism. In a large cohort we compared the results of both techniques.

Methods: 222 patients were investigated by both techniques using the contrast agent Echovist-300 and performing each test once without and once with the Valsalva maneuver (VM).