IAA is a neonatal medical emergency. It warrants immediate infusion of prostaglandin E₁ (PGE₁) to maintain ductal patency as well as stabilization of coexisting HF. Due to the discontinuity between the descending aorta and the arch, blood flow to the descending aorta and its tributaries cannot occur unless the ductus arteriosus stays open. After medical stabilization, surgical correction should occur as soon as possible because of the risk of mortality in untreated IAA. Although there is no difference in mortality between patients with isolated TA malformations and TA-IAA, TA-IAA patients undergo surgery earlier and have a longer hospital length of stay.

The cause of death is usually a combination of greatly increased left-to-right shunt with increased pulmonary blood flow (which results in biventricular failure and pulmonary edema), ductal stenosis, the sequelae of renal failure, and metabolic acidosis. Pulse oximetry will reveal normal saturation in the right arm, with a decreased saturation in the lower extremities. If there is inadequate perfusion to the lower body because of ductal closure, death quickly ensues from the combination of increased left-to-right shunt with increased pulmonary blood flow via the VSD, biventricular congestive heart failure (CHF), pulmonary edema, renal insufficiency, severe metabolic acidosis, and shock. Symptoms of ductal closure include tachypnea, lethargy, and poor feeding. Transthoracic echocardiography is diagnostic. Cardiac CT, MRI, and catheterization are also utilized in the diagnosis of IAA.

References

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