The vascular vise causing TAPVR type I to radiographically mimic TAPVR type III.

A subtype of supracardiac total anomalous pulmonary venous return (TAPVR) consists of the vertical vein passing between the left pulmonary artery and the left mainstem bronchus resulting in relative obstruction to pulmonary venous return. This has been termed the vascular vise. In this situation, the supracardiac type of TAPVR (Type I) may mimic radiographically the infradiaphragmatic type (Type 3).