Diagnosis of tricuspid regurgitation by contrast echocardiography.

Sixty-two subjects underwent M-mode and two-dimensional echocardiographic studies that included imaging of the inferior vena cava (IVC) during upper extremity contrast injections. Group 1 consisted of 10 patients with clinical tricuspid regurgitation (TR). Group 2 consisted of 40 patients without definite clinical signs of TR but with conditions known to be commonly associated with TR (e.g., mitral valve disease, pulmonary hypertension, former tricuspid valve surgery). Group 3 consisted of 12 normal subjects. The IVC could be imaged by two-dimensional echocardiography followed by M-mode in all subjects. M-mode IVC measurements in the absence of contrast were not sufficient to reliably separate TR patients from non-TR patients. IVC contrast was imaged, frequently during deep inspiration, in all 10 group 1 patients, 36 of 40 group 2 patients and three of 12 group 3 normal subjects. Three patterns of contrast appearance in the IVC were observed: "v-wave synchronous" patterns in all but two patients with TR and "a-wave synchronous" or "random" patterns in patients without TR. The presence of TR was independently assessed during angiography or surgery in 26 patients. There were two false-negative echo studies, as judged by lntraoperative palpation of a thrill on the right atrium. There were no false-positive v-wave synchronous studies. M-mode echocardiography was superior to two-dimensional echocardiography in detection of the appearance of contrast in the IVC and ease of pattern interpretation. Recognition of false-positive (a-wave synchronous or random) and false-negative patterns (insufficient central contrast, excessively inferior transducer position) improves the diagnostic accuracy of contrast IVC echocardiography, which is a sensitive and specific method for diagnosing TR.