Early and Timely Surgery for an Atypical Form of Partial Anomalous Pulmonary Venous Return Enabled by a Rare Detection by Detailed Fetal Ultrasound.

While recent advances in fetal echocardiography diagnosis have facilitated the treatment of congenital heart disease (CHD) early in life, many diseases remain overlooked by current recommended ultrasound protocols. Among them, partial pulmonary venous return (PAPVR) is a rare disease for which surgery is indicated; however, it progresses from birth without obvious symptoms. We report a case where we carefully examined the right, left, upper, and lower pulmonary veins (PVs) in more detail than is recommended by standard fetal echocardiography protocols, leading to the early detection of an atypical form of PAPVR. Based on close follow-up after the diagnosis, surgical repair was successfully performed during infancy, resulting in improved right heart enlargement and steady weight gain postoperatively. PAPVR is often overlooked, and its undiagnosed progression can lead to impaired cardiac function in adulthood. As routine fetal ultrasound (FU) examinations frequently omit detailed assessments of PVs, this report highlights the importance of incorporating such detailed evaluations into fetal echocardiography protocols.