Vena comitans is Latin for accompanying vein. It refers to a vein that is usually paired, with both veins lying on the sides of an artery. They are found in close proximity to arteries so that the pulsations of the artery aid
venous return
Venous return is the rate of blood flow back to the heart. It normally limits cardiac output.
Superposition of the cardiac function curve and venous return curve is used in one hemodynamic model.
__TOC__ Physiology
Venous return (VR) is the flow o ...
. Because they are generally found in pairs, they are often referred to by their plural form: venae comitantes.
Venae comitantes are usually found with certain smaller arteries, especially those in the extremities. Larger arteries, on the other hand, generally do not have venae comitantes. They usually have a single, similarly sized vein which is not as intimately associated with the artery.
Examples of arteries and their venae comitantes:
*
Radial artery
In human anatomy, the radial artery is the main artery of the lateral aspect of the forearm.
Structure
The radial artery arises from the bifurcation of the brachial artery in the antecubital fossa. It runs distally on the anterior part of the f ...
and
radial veins
Radial is a geometric term of location which may refer to:
Mathematics and Direction
* Vector (geometric), a line
* Radius, adjective form of
* Radial distance, a directional coordinate in a polar coordinate system
* Radial set
* A bearing fr ...
*
Ulnar artery
The ulnar artery is the main blood vessel, with oxygenated blood, of the medial aspects of the forearm. It arises from the brachial artery and terminates in the superficial palmar arch, which joins with the superficial branch of the radial ar ...
and
ulnar veins
In anatomy, the ulnar veins are venae comitantes for the ulnar artery. They mostly drain the medial aspect of the forearm. They arise in the hand and terminate when they join the radial veins to form the brachial veins.
They follow the same ...
*
Brachial artery
The brachial artery is the major blood vessel of the (upper) arm. It is the continuation of the axillary artery beyond the lower margin of teres major muscle. It continues down the ventral surface of the arm until it reaches the cubital fossa ...
and
brachial veins
In human anatomy, the brachial veins are venae comitantes of the brachial artery in the arm proper. Because they are deep to muscle, they are considered deep veins. Their course is that of the brachial artery (in reverse): they begin where r ...
*
Anterior tibial artery
The anterior tibial artery is an artery of the leg. It carries blood to the anterior compartment of the leg and dorsal surface of the foot, from the popliteal artery.
Structure
Course
The anterior tibial artery is a branch of the poplitea ...
and
anterior tibial veins
The anterior tibial vein is a vein in the lower leg.
In human anatomy, there are two anterior tibial veins. They originate and receive blood from the dorsal venous arch, on the back of the foot and empties into the popliteal vein.
The anterior ...
*
Posterior tibial artery
The posterior tibial artery of the lower limb is an artery that carries blood to the posterior compartment of the leg and plantar surface of the foot. It branches from the popliteal artery via the tibial-fibular trunk.
Structure
The poster ...
and
Posterior tibial veins
The posterior tibial veins are veins of the leg in humans. They drain the posterior compartment of the leg and the plantar surface of the foot to the popliteal vein.
Structure
The posterior tibial veins receive blood from the medial and later ...
*
Fibular artery
In anatomy, the fibular artery, also known as the peroneal artery, supplies blood to the lateral compartment of the leg. It arises from the tibial-fibular trunk.
Structure
The fibular artery arises from the bifurcation of tibial-fibular trunk ...
and
Fibular veins
In anatomy, the fibular veins (also known as peroneal veins) are accompanying veins (venae comitantes) of the fibular artery. Structure
The fibular veins are deep veins that help carry blood from the lateral compartment of the leg. They drain int ...
Examples of arteries that do not have venae comitantes (i.e. those that have "regular" veins):
*
Axillary artery
In human anatomy, the axillary artery is a large blood vessel that conveys oxygenated blood to the lateral aspect of the thorax, the axilla (armpit) and the upper limb. Its origin is at the lateral margin of the first rib, before which it is c ...
and the
axillary vein
In human anatomy, the axillary vein is a large blood vessel that conveys blood from the lateral aspect of the thorax, axilla (armpit) and upper limb toward the heart. There is one axillary vein on each side of the body.
Structure
Its origin ...
*
Subclavian artery and the
subclavian vein
External links
*
Photo of Venae comitantes of the brachial artery
{{Authority control
Human anatomy