Isolated unilateral absence of the left pulmonary artery: a case report.

We report the case of a 37-year-old man with isolated unilateral absence of the pulmonary artery (UAPA), which was diagnosed upon the occurrence of hemoptysis. Plain chest radiography demonstrated decreased left pulmonary volume. Computed tomography of the chest revealed the complete absence of the left pulmonary artery. Angiography revealed marked dilation of the left bronchial artery, inferior phrenic artery, internal thoracic artery, and the arterial branches of the thyrocervical trunk. These arteries were considered as collateral circulation to the left lung. In cases with UAPA, collateral circulation should be evaluated by angiography to obtain useful information for treatment.