[Azygos and hemiazygos connections imaged by two-dimensional, and pulsed and color Doppler echocardiography].

Identification of the azygos or hemiazygos connection is important in the diagnosis of congenital heart disease, especially in cases of the polysplenia syndrome. Although two-dimensional echocardiographic observation of this anomaly has been reported, the direct visualization of drainage sites is still rather difficult. A method for visualizing the azygos or hemiazygos connection by a combined use of two-dimensional and pulsed and color Doppler echocardiography was reported here. Subjects consisted of 10 patients with the polysplenia syndrome, each of whom had been confirmed as having the azygos or hemiazygos connection; five each of the azygos and hemiazygos types. The transducer was placed over the second intercostal space on the right side for the azygos, and on the left side for hemiazygos connection. The two-dimensional echocardiographic plane was adjusted to visualize the long-axis view of the superior vena cava; the right superior vena cava for the azygos and the left superior vena cava for the hemiazygos connection. The mode of the equipment was changed to color Doppler, and an orange-colored blood flow toward the transducer, draining into the superior vena cava was carefully sought. Finally the pulsed Doppler mode was selected and the sampling volume was set in the orange-colored area. The wave form of the pulsed Doppler echocardiogram of the azygos or hemiazygos vein potentially had two peaks per cardiac cycle, and was modified by respiration. We found azygos or hemiazygos veins coursing from the posterior aspect of the right pulmonary artery in seven of 10 cases by two-dimensional echocardiography alone, while we observed all veins by the additional use of color and pulsed Doppler echocardiography.