Multimodal imaging of infantile scimitar syndrome with Eisenmenger physiology: A case report of complex intracardiac and extracardiac shunts.

Scimitar syndrome is a rare congenital vascular malformation in which the right pulmonary veins drain abnormally into the inferior vena cava, right atrium, or portal vein instead of the left atrium. It occurs in about 1-3 per 100,000 live births and has 2 forms: an infantile form, usually more severe and associated with multiple anomalies and poorer prognosis, and a child/adult form, which is often milder or asymptomatic. This report describes an 8-year-old boy diagnosed with complex Scimitar syndrome complicated by Eisenmenger syndrome. Echocardiography, chest X-ray, and computed tomography angiography showed right lung hypoplasia, anomalous drainage of the right pulmonary veins into the supradiaphragmatic inferior vena cava, systemic arterial supply to the right lung, large atrial septal defect and patent ductus arteriosus with bidirectional shunting, severe pulmonary hypertension, and right heart enlargement-findings consistent with long-standing left-to-right shunt and subsequent shunt reversal. Management in Scimitar syndrome depends on shunt size, pulmonary pressures, and associated anomalies. Mild cases with small shunts may be managed with regular follow-up, whereas patients with significant left-to-right shunting, right heart strain, or recurrent infections usually benefit from surgery. In advanced cases with established Eisenmenger physiology, as in this patient, curative surgery is generally not possible and treatment is mainly medical and supportive, underscoring the importance of early imaging-based diagnosis and timely referral.