Transposition of the Great Arteries Treatment & Management

• Initial treatment consists of maintaining ductal patency with continuous intravenous (IV) prostaglandin E₁ infusion to promote pulmonary blood flow, increase left atrial pressure, and promote left-to-right intercirculatory mixing at the atrial level. This is particularly important in patients with severe left ventricular outflow tract stenosis or atresia. Prostaglandin therapy may or may not benefit the patient with simple transposition of the great arteries (TGA) and an intact ventricular septum without left ventricular outflow tract obstruction.
• Cardiac catheterization, depending on the degree of restriction at the atrial septum and the timing of operative repair, is indicated for a balloon atrial septostomy in severely hypoxemic patients with an inadequate atrial level communication and insufficient mixing. The balloon atrial septostomy is used to increase the atrial level shunt and to improve mixing.
• For the ill neonate, metabolic acidosis should be corrected with fluid replacement and bicarbonate administration.
• Mechanical ventilation may be necessary if pulmonary edema develops in concert with severe hypoxemia.
• Ultimately, the patient requires surgical repair or palliation early in life.

Surgical approach depends on the age of the patient at presentation, the presence of associated congenital cardiac lesions, and the experience of the cardiothoracic surgeon with a given surgical technique. Most full-term neonates with uncomplicated transposition of the great arteries can undergo an arterial switch procedure in one operation, with minimal mortality.

• Transposition of the great arteries with intact ventricular septum: The ideal operation is an arterial switch procedure. It represents an anatomic repair and establishes ventriculoarterial concordance. This procedure should be performed when the infant is younger than 4 weeks, as the left ventricle may not be able to handle systemic pressure postoperatively if left too long in the low-pressure, low-resistance pulmonary circuit. Rarely, however, depending on the particular coronary artery anatomy (eg, intramural coronary artery), coronary artery translocation may not be feasible, and an arterial switch is not recommended. In this subgroup, an atrial level switch (Senning or Mustard procedure) has lower surgical and short-term morbidity and mortality.
• Transposition of the great arteries with ventricular septal defect: The preferred operation is an arterial switch procedure with ventricular septal defect closure. If the ventricular septal defect is large and nonrestrictive and coronary artery anatomy makes an arterial switch operation inadvisable, a Rastelli-type intracardiac repair may be feasible. With the Rastelli-type procedure, waiting until the infant is older and larger may be preferred because of the need for a right ventricle–pulmonary artery conduit in the Rastelli operation. If the infant has excessive congestive heart failure (with growth failure), it may be advisable to either proceed with reparative surgery or, if not feasible, band/ligate the main pulmonary artery and place an aortopulmonary shunt during the newborn period to restrict pulmonary blood flow.
• Transposition of the great arteries with ventricular septal defect and left ventricular outflow tract obstruction: An arterial switch operation may not be feasible due to pulmonary (left ventricular outflow tract) stenosis or atresia. If the ventricular septal defect is nonrestrictive and not too remote from the aorta, a Rastelli intracardiac repair could be possible. Because the Rastelli procedure necessitates a conduit from the right ventricle to the pulmonary artery, delaying repair until the infant is older and larger may be preferable. In this case, placing an aortopulmonary shunt during the newborn period may be necessary to establish adequate pulmonary blood flow while waiting.
• Transposition of the great arteries with ventricular septal defect and pulmonary vascular obstructive disease: These patients might not be appropriate surgical candidates because of the progressive increase in pulmonary vascular resistance. This is a small subgroup of patients whose conditions are not often diagnosed until after a palliative or reparative procedure is performed.

• Pediatric cardiologist
• Pediatric cardiothoracic surgeon

• Patients with transposition of the great arteries and a large ventricular septal defect who have not undergone repair may require increased caloric density during infancy (120-130 kcal/kg/d), particularly if they have significant congestive heart failure and poor weight gain.
• Following definitive repair, most patients do not need a special diet.

• No specific activity requirements are necessary.