Fig 2. a. A network of small multiple coronary vessels (*) around aorta (AO), being the small initial collaterals between the left and right coronary artery; b. a systo-diastolic jet of flow into the MPA which represents the left-to-right shunt through the abnormal coronary vessel; c. the origin (*) of the RCA from the MPA (ARCAPA) with retrograde inverted «blue» flow inside, running anterior to the aorta. d. CT-scan image showing RCA arising (*) from MPA.