Tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries 2012-04-10T07:43:01Z Major aortopulmonary collateral arteries (MACPAs) are arteries that develop to supply blood to the lungs when native pulmonary circulation is underdeveloped. That is, the blood supply to the lungs derives from the aorta rather than from the pulmonary artery. A type of tetralogy of Fallot with pulmonary atresia in which all pulmonary blood flow is derived from major aortopulmonary collateral arteries (MAPCA). UMLS:C4023234 HP:0011678 Tetralogy of Fallot with pulmonary atresia