Vena comitans (Latin for accompanying vein, also known as a satellite vein) refers to a

vein Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and feta ...

that is usually paired, with both veins lying on the sides of an

artery An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...

. 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.

Function

As the vein is found in close proximity to an artery 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 ...

Claude Bernard Claude Bernard (; 12 July 1813 – 10 February 1878) was a French physiologist. I. Bernard Cohen of Harvard University called Bernard "one of the greatest of all men of science". He originated the term ''milieu intérieur'' and the associated c ...

suggested the interchange of heat between the arteries and adjacent veins might moderate cooling of the arterial blood, for which there is experimental evidence.

Examples

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 ...

and radial veins *

Ulnar artery The ulnar artery is the main blood vessel, with oxygenated blood, of the Human Anatomical Terms#Anatomical directions, medial aspects of the forearm. It arises from the brachial artery and terminates in the superficial palmar arch, which joins ...

and ulnar veins *

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 *

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 popliteal ...

and anterior tibial veins *

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 posteri ...

and posterior tibial veins * Fibular artery and fibular veins 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 * Subclavian artery and the

subclavian vein The subclavian vein is a paired large vein, one on either side of the body, that is responsible for draining blood from the upper extremities, allowing this blood to return to the heart. The left subclavian vein plays a key role in the absorption ...

References

External links

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Photo of Venae comitantes of the brachial artery
{{Authority control Human anatomy