Detection and evaluation of intrapulmonary vascular shunt with "contrast Doppler" transesophageal echocardiography. Contrast echocardiography is useful for detecting intrapulmonary right-to-left shunt lesions. In a patient with suspected pulmonary arteriovenous fistula, contrast transesophageal echocardiography was used to demonstrate the presence of a right-to-left shunt. By use of a combination of two-dimensional echocardiography, contrast injection, and pulsed Doppler echocardiography, each pulmonary vein was successfully interrogated for evidence of contrast shunting. This case demonstrates that contrast transesophageal echocardiography is useful for the detection of intrapulmonary fistulas and that it has the potential for localization of the shunt lesion. 