Congenital pulmonary arteriovenous malformation: a rare cause of cyanosis in childhood

Pulmonary arteriovenous malformation (PAVM) is a rare condition in which there is abnormal connection between pulmonary arteries and veins. The disorder usually appears in late childhood or early adult life, with dyspnea on exertion, clubbing or cyanosis. We present two patients with severe cyanosis and their work-up to diagnosis of PAVM, as a rare cause of cyanosis in childhood.