Superior vena cava obstruction syndrome after an arterial switch operation for complete transposition of the great arteries in a preterm infant: a case report and literature review

Complete transposition of the great arteries (TGA) is a critical cyanotic congenital heart disease (CHD) requiring early surgical correction. Central venous catheterization is an important risk factor for venous thrombosis and superior vena cava obstruction syndrome (SVCS). SVCS following an arterial switch operation (ASO) in a premature infant is rarely reported. We describe one of the few reported cases of postoperative SVCS in a premature infant and discuss its clinical course and individualized management. A male premature infant born at 33 + 4 weeks of gestation with a prenatally and postnatally diagnosed TGA with an intact ventricular septum (TGA-IVS) underwent an ASO on postnatal day 8. His postoperative course was complicated by generalized edema, chylothorax, pericardial effusion, hydrocephalus, severe infection, and feeding intolerance. Bedside ultrasound revealed catheter-associated SVC thrombosis, and contrast-enhanced computed tomography (CT) confirmed complete proximal SVC occlusion with collateral vein formation. The central venous catheter (CVC) was removed, and the patient received unfractionated heparin (UFH) followed by low-molecular-weight heparin (LMWH), together with comprehensive supportive treatment. His edema, respiratory symptoms, and pleural effusion gradually improved. However, follow-up imaging showed persistent SVC occlusion without anatomical recanalization. Anticoagulation was discontinued after multidisciplinary review because the obstruction was considered organized and the patient remained clinically stable with adequate collateral venous drainage. At 11 months of age, telephone follow-up confirmed satisfactory feeding, growth, and development. SVCS should be considered in infants with CVCs who develop upper-body edema, chylothorax, or other signs of impaired systemic venous return after congenital heart surgery. Early imaging assessment and timely catheter removal are critical Carefully monitored anticoagulation may be considered in selected patients when catheter-based or surgical intervention is technically unsuitable. However, clinical improvement does not necessarily indicate thrombus resolution or restoration of SVC patency. In this patient, clinical stability was achieved despite persistent SVC occlusion in the presence of extensive collateral venous drainage. Management should therefore be individualized through multidisciplinary evaluation.