Prenatal Diagnosis of Persistent Left Superior Vena Cava Raises Suspicion for Coarctation of Aorta

A pregnant woman was referred to our hospital with a persistent left superior vena cava (PLSVC) and a slightly smaller left heart at 35 weeks of gestation. Fetal echocardiography revealed a small aortic valve and a slightly narrow aortic isthmus. A PLSVC was identified in the dilated coronary sinus. We did not suspect strong coarctation of the aorta (CoA). Echocardiography on postnatal day 0 revealed a slightly narrow isthmus (3.1 mm with a pressure gradient of 5-10 mmHg). When the ductus arteriosus was closed, the isthmus narrowed rapidly to 2.4 mm, and the pressure gradient reached 30 mmHg, which was an indication of surgical arch repair. Aortic arch repair was performed with cardiopulmonary assistance on postnatal day 23. This case presents two lessons. First, when PLSVC is prenatally diagnosed, CoA should be suspected. Second, once CoA is suspected, careful observation of the aortic arch, particularly the isthmus, should be performed.