Scimitar syndrome

Imaging description A full-term neonate developed respiratory distress at birth. There was a history of in utero diagnosis of complex heart disease including hypoplastic left heart as well as a hypoplastic right lung. The chest radiograph at birth (Fig. 26.1a) demonstrated decreased volume of the right lung with dextroposition of the heart. Echocardiography demonstrated a large atrial septal defect (ASD), hypoplastic left heart, and large patent ductus arteriosus (PDA). CT angiography of the chest on day 2 of life demonstrated findings consistent with scimitar syndrome, including abnormal pulmonary venous drainage of the right lung into the inferior vena cava (IVC) via a scimitar vein in the right lower lung (Fig. 26.1b). In addition a small right pulmonary artery was noted with the hypoplastic right lung (Fig. 26.1c). There was also evidence of a right lower lobe horseshoe lung extending posteriorly across the midline behind the IVC to interface with the left lung (Fig. 26.1b). This received arterial supply from an aberrant proximal right pulmonary artery branch (Fig. 26.1c). Venous drainage and airway bronchial branches of this segment were also on the right side (not shown). Dextroposition of the heart was noted along with a hypoplastic left ventricle and large ASD (not shown). Also seen was a large PDA and juxtaductal coarctation of the aorta as well as a left-sided superior vena cava (SVC) draining to the coronary sinus (Fig. 26.1d, e).