Case report: the 'vanished' left pulmonary artery.

Background:We report a case of isolated ductal origin of pulmonary artery (DOPA) diagnosed in an asymptomatic newborn. The primary aim of this case is to highlight the need to investigate for DOPA in patients diagnosed with an 'absent branch pulmonary artery'. Case summary:Our patient was an asymptomatic newborn infant, with normal intracardiac anatomy. He was initially diagnosed post-natally with 'absent left pulmonary artery' (LPA), though the LPA was seen in antenatal scans. He underwent angiography and was re-diagnosed with bilateral arterial ducts, with ductal origin of the LPA from the left arterial duct. The LPA was salvaged by first stenting the left arterial duct on Day 11 of life, with subsequent surgery to connect the LPA to the main pulmonary artery at 4.5 months old. The patient had an uneventful recovery after the surgery. Discussion:Ductal origin of pulmonary artery is a rare vascular anomaly characterized by continuity of the left or right pulmonary artery (PA) with the distal end of the arterial duct, and discontinuity with the main PA. It is commonly misdiagnosed as pulmonary artery agenesis when the patent arterial duct constricts, with cessation of blood flow into the affected pulmonary artery. A high index of suspicion is necessary for diagnosis of DOPA. Once diagnosed, this lesion is clearly amenable to intervention, with benefits from unifocalization, to prevent late onset pulmonary hypertension or cardiac failure.