Angiography of azygos continuation of inferior vena cava in situs ambiguus with left isomerism (polysplenia syndrome).

We have in our records 11 patients with situs ambiguus and left isomerism (polysplenia). Ten had an interruption of the inferior vena cava (IVC) with azygos continuation; in eight cases the continuation was to the left superior vena cava (LSVC), in one case to the right superior vena cava (RSVC) and in one case to both the LSVC and RSVC. Two patients underwent surgical correction by a baffle procedure of the functioning single atrium. The angiographic confirmation of the azygos system anatomy is important in planning the surgical correction of patients with left isomerism. Clinically, given the same heart defects with normal pressures, the right-sided drainage is probably more favorable, producing less peripheral desaturation.