Aberrant origin of left pulmonary artery (vascular sling). Report of the clinical and anatomic features in three patients.

The clinical and anatomical findings in 3 patients with aberrant origin of the left pulmonary artery from the right pulmonary artery ("vascular sling") are presented. All 3 children symptoms of severe respiratory distress shortly after birth. In 2 children the correct diagnosis was suggested from the roentgenogram of the thorax, because of an indentation in the anterior wall of the esophagus. The diagnosis was further endorsed by selective angiography of the aberrant left pulmonary artery. The second patient is of particular interest, since the correct diagnosis was missed because of the presence of a multitude of associated anomalies. These included a tracheobronchial anomaly, a ventricular septal defect with a dilated pulmonary trunk, and a left-ward shift of the heart secondary to pulmonary emphysema on the right. Therefore, the indentation in the esophagus was absent, while the shift and rotation of the heart led to a misinterpretation of the exact course of the left pulmonary artery on the angiocardiogram. These cases are presented to reemphasize that "vascular sling", although rare, is indeed a serious cause of respiratory distress in infancy. Early recognition is of vital importance, since surgical repair of the vascular anomaly seems to be the only benificial procedure in these patients.