Unilateral absence of a pulmonary artery: a rare disorder with variable presentation.

Unilateral absence of a pulmonary artery (UAPA) is a rare condition with an estimated prevalence of 1 in 200,000 young adults. Most commonly, UAPA occurs in conjunction with cardiovascular abnormalities such as tetralogy of Fallot or cardiac septal defects, but it can also occur in an isolated manner. Patients with isolated UAPA can remain asymptomatic into late adulthood but usually report symptoms such as dyspnea or chest pain or suffer from hemoptysis or recurrent infections. Diagnosis can be difficult due to the rarity of the condition and its nonspecific presentation. We present a case of a 61-year-old man who presented for lung transplant evaluation and was found to have UAPA. Typical findings on chest radiograph, strategies for diagnosis, and available treatments are discussed.