Familial persistent pulmonary hypertension.

We report three siblings who presented with a clinical picture of persistent pulmonary hypertension of newborn and died between 4 and 15 days of age. Pulmonary artery pressure in all was above systemic values, with a right to left shunt via either the foramen ovale or ductus arteriosus, or both. Histology of the pulmonary vascular bed showed extension of muscle into small arteries which are normally non-muscular.