August 2000 Chest x-ray may show a narrow mediastinum because the great vessels are superimposed rather than side by side to each other and the main pulmonary artery segment is not in its usual location. The heart resembles the shape of an egg due to dilatation of the left ventricle and right atria. Pulmonary venous congestion may develop rapidly.
Neonatal electrocardiogram is normal.
The diagnosis should be confirmed immediately by echocardiography. In infants with life-threatening hypoxemia, Prostaglandin E1 keeps ductus arteriosus open, leading to increased pulmonary blood flow, and temporary improvement in systemic oxygenation. Surgical repair by the Arterial Switch technique with coronary artery reimplantation is usually performed within the first 7 to 10 days of life before left ventricular atrophy has developed. Average life expectancy of a child with d-TGA with intact ventricular septum is 6 months without surgical correction. Image provided by University of Iowa Department of radiology Medical Student Teaching Cases.