Abnormal cerebral hemodynamics in preterm infants with patent ductus arteriosus.

Blood flow patterns in the anterior cerebral arteries were studied in eight preterm infants with patent ductus arteriosus and left-to-right shunts. A noninvasive Doppler technique was used to obtain the blood flow patterns and to calculate a pulsatility index. Advancing diastolic blood flow was decreased in all eight infants, and two demonstrated retrograde anterior cerebral artery flow during diastole. Following ductal closure, the diastolic flow in the anterior cerebral arteries increased significantly, reaching levels seen in normal infants. These observations demonstrate that infants with patent ductus arteriosus and left-to-right shunts may have abnormal cerebral hemodynamics which return to normal following ductal closure.