Clinical deterioration following arterial switch surgery due to extensive aortopulmonary collaterals, unusual condition but worth considering: case report.

Although the occurrence of MAPCAs with D-TGA-IVS is infrequent, clinicians should suspect their presence in cases with unexplained heart failure, pulmonary hemorrhage, or cardiovascular compromise after ASO. Catheter closure of MAPCAs is feasible with an acceptable short-term outcome.