Hypoplastic pulmonary artery: an unusual entity mimicking pulmonary embolism during pregnancy.

Hypoplastic pulmonary artery is an unusual congenital malformation. We describe a case of hypoplastic pulmonary artery diagnosed during the third trimester of pregnancy. The clinical and radiologic features mimicked pulmonary embolism, including hemoptysis, chest pain, pleural effusion, mild hypoxemia, and a suggestive ventilation-perfusion scan. Accurate differentiation of this entity from pulmonary embolism is necessary to obviate the need for prolonged anticoagulation.