Superior phrenic arteries
Arteriae phrenicae superiores
Small paired branches from the lowest part of the thoracic aorta that feed the back of the diaphragm on its thoracic face.
At a glance
- English
- Superior phrenic arteries
- Latin (TA2)
- Arteriae phrenicae superiores
- System
- Artery
- Region
- Trunk
- Side
- Single, on the midline
About the superior phrenic arteries
The superior phrenic arteries are a pair of slender vessels that leave the thoracic aorta just above the diaphragm. They are the lowest of the small visceral and parietal branches the descending aorta gives off in the posterior mediastinum, and they arise from its front or sides shortly before it passes through the aortic hiatus. Sometimes there are more than two, and they can be very small.
Each vessel runs a short course downwards and outwards onto the thoracic (upper) surface of the diaphragm. They spread over the posterior part of that surface, near the vertebral column and the crura, rather than over the dome as a whole. The rest of the diaphragm draws its blood from several other sources, which explains why these arteries can be modest in size.
On the upper surface their twigs meet branches of two vessels that come from the internal thoracic artery. In front and at the sides they join the musculophrenic artery, which follows the costal margin, and more centrally they connect with the pericardiacophrenic artery, which descends with the phrenic nerve between the pericardium and the pleura. On the abdominal side, the inferior phrenic arteries from the abdominal aorta supply the under surface, and the lower posterior intercostal arteries reach the edges.
This overlapping supply means that the diaphragm is rarely deprived of blood when one source is lost. The superior phrenic arteries matter mainly as landmarks of the very end of the thoracic aorta and as small vessels that may need attention in surgery on the lower oesophagus or the aortic hiatus. Their companion veins drain back into the azygos system.
Course and supply
- Arises from
- The anterior or lateral surface of the lowest part of the thoracic aorta, just above the aortic hiatus.
- Ends in
- Spread over the back of the thoracic face of the diaphragm, where they join twigs of the pericardiacophrenic and musculophrenic arteries.
- Supplies
- Supply the posterior part of the thoracic surface of the diaphragm.
Anthromica
See the superior phrenic arteries where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
