Abstract
We report a case of a fetus with premature constriction of the ductus arteriosus (PCDA) diagnosed by prenatal fetal echocardiography. The mother was administered indomethacin for tocolysis and acetaminophen at week 31 of gestation. Fetal echocardiography showed enlargement of the right atrium (RA) and right ventricle (RV) with hypertrophic RV, moderate tricuspid valve regurgitation (TR), and a narrowed ductus arteriosus (DA). We continued to perform fetal echocardiography until the fetus matured to assess fetal cardiac function after the medication was discontinued. Right heart failure of the fetus was not noticed during the pregnancy. A male infant was delivered at 37 weeks and 5 days of gestation by cesarean section. Although echocardiography just after birth revealed marked RV pressure overload, the infant was in good condition without any treatment; subsequently, the RV pressure normalized after 1 month. Typically, urgent delivery is thought to be required in cases of PCDA. However, in some patients, constriction of the DA can be reversed by discontinuation of medication. Echocardiographic examinations of the fetus can be used to determine the appropriate timing of delivery.