Unilateral pulmonary artery agenesis: An unusual cause of hemoptysis

INTRODUCTION: Unilateral pulmonary artery agenesis (UPAA) is a rare congenital malformation of the pulmonary artery due to agenesis of the sixth aortic arch during embryogenesis. Diagnosis can be challenging due to variable clinical presentations. CASE: A 29-year-old female at third trimester of twin pregnancy presented with massive hemoptysis. Computed tomography angiogram (CTA) showed unilateral absence of the right pulmonary artery with multiple dilated tortuous bronchial arteries supplying the right lung. Selective embolization of the bronchial artery was performed post-partum. CONCLUSION: Clinicians should have a high clinical suspicion of collateral artery bleeding in patients who present with unexplained hemoptysis and typical UPAA radiographic findings.