Congenital misalignment of pulmonary vessels: an unusual syndrome associated with PPHN.

We report a case of misalignment of pulmonary vessels and review the clinical features of all 13 cases reported to date. All were term infants dying from severe persistent pulmonary hypertension of the newborn. We have identified a triad of features that will alert neonatal clinicians to the possibility of this diagnosis: association with other non-lethal congenital malformations; delayed onset of presentation (especially after 12h); and severe hypoxaemia refractory to conventional therapy. We recommend that any autopsy on newborn infants include a specific search for misalignment of pulmonary vessels to outline the pathophysiology and clinical significance of this disorder.