Major aortopulmonary collateral arteries

Major aortopulmonary collateral arteries (MAPCAs) are persistent tortuous fetal arteries that arise from the descending aorta and supply blood to pulmonary arteries in the lungs usually at the posterior aspect of hilum.


Embryologically, the intersegmental arteries regress with the normal development of pulmonary arteries. 

They may persist to supply the pulmonary arteries when there is no flow or very little flow into the pulmonary arteries from the right ventricle. If there is an alternate supply to the pulmonary arteries (e.g. patent ductus arteriosus), then the fetal arteries regress and such patient does not have MAPCAs 1.


They usually arise from the descending aorta. Less commonly, they may arise from ascending aorta or subclavian arteries.

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Article information

rID: 36728
Tag: stub, cases
Synonyms or Alternate Spellings:
  • Major aortopulmonary collateral artery (MAPCA)
  • Major aortopulmonary collateral arteries (MAPCAs)
  • Major aortopulmonary collateral artery

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Cases and figures

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    Case 1
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    Case 2: with heterotaxy syndrome
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