Venous system

The **venous system** is a network of blood vessels—veins—that return deoxygenated blood from the body’s organs and tissues back to the heart. It consists of deep veins, superficial veins, and connecting (perforator) veins. The venous system operates under low pressure compared to arteries and relies on one-way valves as well as muscle contractions (especially in the legs) to prevent backflow and assist blood return against gravity[1][3][4][9]. Besides transporting waste-laden blood for reoxygenation in the lungs, it plays roles in thermoregulation by adjusting skin blood flow, acts as a reservoir for circulating blood volume, supports immune responses by transporting immune cells during injury or infection, and helps regulate fluid balance[3][6]. Dysfunction of this system can lead to various cardiovascular diseases such as chronic venous insufficiency or thrombosis.

Other names

Vein networkSystemic venous systemPulmonary venous systemVeins