Systemic venous system

In human anatomy, the systemic venous system refers to veins that drain into the right atrium without passing through two vascular beds (i.e. they originate from a set of capillaries and do not pass through a second set of capillaries before reaching the right side of the heart).

The term systemic venous system is often used to differentiate veins from veins that drain the pulmonary system (the pulmonary venous system) and veins that drain the digestive tract (the portal venous system).

Large veins that are considered part of the systemic venous system are the:

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