PM1001: A Combination of Rare Vascular Anomalies Involving Major Vessels

Introduction: Scimitar syndrome is a rare congenital anomaly associated with right lung hypoplasia, partial anomalous pulmonary venous drainage, and hypoplasia of the right pulmonary artery (RPA). Presentation and timing of symptoms are variable with respiratory distress, heart failure, and/or pulmonary hypertension. There are rare reports of Scimitar syndrome presenting with VACTERL association as well as with left pulmonary artery (LPA) sling. VACTERL association is a constellation of vertebral, anorectal, cardiac, tracheoesophageal, genitourinary, and limb malformations. LPA sling is a vascular anomaly with the left pulmonary artery arising from the right pulmonary artery, coursing between the esophagus and trachea leading to compression.

Case Description: A newborn, late preterm male presented with fetal growth restriction and fetal diagnosis of Scimitar syndrome (cardiac dextroposition, right lung hypoplasia, hypoplastic RPA, and anomalous right pulmonary veins connecting to inferior vena cava) as well as a large ventricular septal defect (VSD), persistent left superior vena cava draining to the coronary sinus, and atrial septal defect. Additionally, there was an unusual course of the left pulmonary artery (LPA) with suspicion of an LPA sling. Postnatal echocardiography confirmed the cardiac anatomy and demonstrated a prominent aortopulmonary collateral (APC/Scimitar artery) arising from the abdominal aorta. He was found to have microcephaly and an imperforate anus for which he underwent an open colostomy with mucous fistula creation on the day of life (DOL) 1. Cardiac computed tomography (CT) was performed to further delineate the anatomy. It showed aortopulmonary collateral to the right lung originating from the celiac artery. (Figure 1, 2) Chest CT showed horseshoe lung, hypoplastic right bronchus, and rib anomalies meeting the clinical criteria for VACTERL association. On DOL 20, cardiac catheterization was performed and two branches of the APC were device and coil occluded to decrease the left to right shunt. On DOL 23, he underwent surgical repair of the LPA sling and VSD closure. Bronchoscopy revealed significant improvement in tracheal obstruction. He required a gastrostomy feeding tube and was discharged home on DOL 55.

Discussion: Scimitar syndrome is a rare congenital malformation with rare reports of association with both VACTERL and LPA sling. However, not all of them are diagnosed prenatally. Patients with this combination are at risk for congestive heart failure and pulmonary hypertension in the neonatal period.

Conclusion: Here we present a case of prenatal suspicion of LPA sling and Scimitar syndrome which led to earlier postnatal diagnosis and intervention, preventing tracheoesophageal compression. Advanced imaging is very helpful to delineate the origin and course of these anomalous great vessels.