Intraesophageal aortopulmonary collateral artery occlusion in an infant with Tetralogy of Fallot and flow-dependent major aortopulmonary collateral arteries.

Patients with flow-dependent aortopulmonary collateral arteries often exhibit tenuous clinical statuses. Here we present an infant with Tetralogy of Fallot with pulmonary atresia (TOF-PA) and major aortopulmonary collateral arteries (MAPCAs) who experienced clinically significant oxygen desaturations during feedings. These frequent episodes were attributed to gastroesophageal reflux. In preparation for possible surgical correction of her complex congenital heart condition, she was intubated for a cardiac catheterization to better characterize her anatomy, but terminally decompensated shortly after extubation and restarting feeding. On autopsy, very mild evidence of esophageal reflux was present; instead, one of her four aortopulmonary collateral arteries was unexpectedly discovered traversing through the muscular layer of her esophageal wall. This finding was confirmed microscopically with significant intimal hyperplasia compared to uninvolved collateral arteries. The remainder of the autopsy findings, including her myocardium, lungs, and esophagus, were unremarkable. Given the feeding-associated oxygen desaturations present in life and the aberrant collateral artery's comparative stenosis at death, we speculate that the repetitive trauma of esophageal peristalsis was not only significant enough to temporarily impact oxygenation but, over time, led to near-occlusion of the intraesophageal collateral artery, which may have contributed to the terminal decompensation of this already tenuous patient.