Right superior phrenic vein

At a glance

English

Right superior phrenic vein

Latin (TA2)

Vena phrenica superior dextra

System

Vein

Region

Trunk

Side

Single, on the midline

About the right superior phrenic vein

The superior phrenic veins are small vessels that drain the posterior part of the upper, thoracic surface of the diaphragm. On the right side the superior phrenic vein accompanies the right superior phrenic artery, one of the small branches that the lower thoracic aorta sends forward onto the diaphragm just above the aortic hiatus.

The vein gathers blood from the muscle of the posterior diaphragm close to the vertebral column and runs back with its artery towards the spine. On the right it drains into the azygos vein, which lies on the right side of the lower thoracic vertebral bodies; the left superior phrenic vein drains correspondingly into the hemiazygos.

The superior phrenic veins are only part of the venous drainage of the diaphragm. Much of the upper surface drains forward and laterally through the pericardiacophrenic and musculophrenic veins into the internal thoracic veins, while the undersurface is drained by the inferior phrenic veins, which on the right enter the inferior vena cava.

The vein has little clinical importance on its own. It is one of many small connections between the systemic veins of the thoracic wall and the azygos system, and these connections can enlarge to carry collateral blood when a vena cava is obstructed.

Course and drainage

Begins at

Begins in the posterior part of the upper surface of the right half of the diaphragm.

Drains into

Drains into the azygos vein beside the lower thoracic vertebrae.

Drains

Drains the posterior part of the thoracic surface of the diaphragm on the right.