DUCTUS ARTERIOSUS-DEPENDENT PULMONARY CIRCULATION SECONDARY TO CARDIAC-MALFORMATIONS IN FETAL LIFE

The objective of this study was to describe the characteristic prenata l findings of a ductus arteriosus-dependent pulmonary circulation seco ndary to cardiac malformations. B-mode, color and pulsed wave Doppler echocardiography were performed in seven fetuses with severe pulmonary stenosis or atresia. All findings were confirmed postnatally by echoc ardiography and cardiac catheterization or autopsy. Severe fetal pulmo nary stenosis or at atresia was characterized by decreased pulmonary v alve diameters, frequently with reduced pulmonary artery diameters, in creased flow velocities or absent flow across the stenotic pulmonary v alve, increased ascending aorta diameters, slightly increased aortic v elocities and normal umbilical and middle cerebral artery Doppler wave forms. In all cases, prenatal assessment of neonatal ductus dependenc e was possible by demonstrating reverse flow across the fetal ductus w ith peak systolic velocities ranging from 0.9-2.0 m/s and absent diast olic flow. Ductal diameters were slightly decreased, ranging from 2-4 mm. Prenatal detection of a ductus-dependent pulmonary circulation is a strong indication of the presence of severe pulmonary stenosis or at resia. Its diagnosis allows avoidance of maternal administration of dr ugs with constrictive effects upon the ductus, interdisciplinary plann ing of perinatal management, early postnatal confirmation of the diagn osis, and early postnatal intervention, in particular administration o f prostaglandins to prevent life-threatening ductal closure.