Venous return

The venous return is the phenomenon of the increase of the blood of the bottom of the body (impoverished out of oxygen) towards the upper part of the body to be reloaded there. This return is possible by the presence of valves anti return in the veins and the compression of the veins by the muscles involving a way of possible blood only upwards. One calls arterial blood the blood which comes from the Cœur charged out of oxygen, and blood venous the blood which already distributed oxygen to the cells.

The phenomenon of the venous return results physically in a pressure exerted on the venous walls proportional to:

vertical size of the blood system
the Compliance of this system.

The effort of the heart (left Ventricle) is to pump blood in the Aorte to send it has all the body (except the lungs which is fed by the ventricle right via the pulmonary Artère). That explains the more important volume of this ventricle compared to the right.

The venous return is thus facilitated by:

a good muscular tonicity, which will make it possible the veins not to subside under the weight of the blood which goes up because compressed, constant by the muscular structure. (the Varice is a direct consequence of this factor).
a cardiac good health: a heart not weakened will be less tired to provide the pressure necessary to the sending of blood towards the bodies and its return.

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