In utero development of hypertensive necrotizing pulmonary arterial lesions: Report of a case associated with premature closure of the ductus arteriosus and pulmonary hypoplasia

Premature closure of the ductus arteriosus (PCDA) is an uncommon defect in which pulmonary hypertension (PH) has been documented by echocardiography i n patients and by direct measurement after experimental PCDA in animals, Th e pulmonary vascular histology in human cases has received little attention but in the few recorded observations the vessels were either normal or sho wed increased muscularity. We report the case of a 31 week hydropic female stillborn monozygotic twin in whom postmortem examination disclosed PCDA an d hypoplasia of the lungs. Atypical plexiform lesions with necrotizing pulm onary arteritis were present. These lesions represent vascular consequences of severe pulmonary hypertension produced by greatly enhanced blood flow t hrough a restricted vascular bed resulting from the combined effects of the se two abnormalities. The findings in this case of PCDA with presumed sever e PH indicate that severe pulmonary vascular changes can develop in utero a nd that the interval of time needed for development of such changes in seco ndary PH is relatively short. Cardiovasc Pathol 2000;9.39-47 (C) 2000 by El sevier Science Inc.