Ronald I Clyman, M.D.


Research Interests:
Cardiology, Cell Biology, Developmental Biology, Neonatology, Neonatal Cardiology

The ductus arteriosus is a vital fetal blood vessel that diverts blood away from the fetus’s lungs and towards the placenta during life inside the uterus. After birth it is essential that the ductus arteriosus constricts and obliterates itself so that the normal postnatal pattern of blood flow can be established. Essentially all full term infants will have closed their ductus by the third day after birth. Preterm infants of less than 30 weeks gestation have a high chance of having a persistently open or patent ductus arteriosus (PDA). If the ductus arteriosus remains open it contributes to the development of several neonatal morbidities: prolonged ventilator dependency, pulmonary hemorrhage, pulmonary edema, chronic lung disease and necrotizing enterocolitis. Our laboratory has been studying the factors that regulate normal closure of the ductus arteriosus in full term infants and abnormal persistent ductal patency in preterm infants. Approaches used to study this problem are: controlled clinical trials, integrated whole animal physiology, in vitro organ culture, and cell biology.

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