What is the term for an abnormal connection between a high-pressure arterial system and a low-pressure venous system?

An abnormal connection between a high-pressure arterial system and a low-pressure venous system is known as an arterial-venous fistula. This condition involves a direct communication between an artery and a vein, bypassing the capillary network. The high pressure from the arterial side can lead to increased blood flow into the vein, which may not be equipped to handle such pressure, potentially causing the vein to enlarge or become varicosed over time.

Arterial-venous fistulas can occur naturally or may be created surgically for various medical purposes, such as for dialysis access. Understanding this condition is essential in vascular studies, as it represents a significant anatomical and physiological change that can impact blood flow dynamics.

In contrast, a vein graft refers to a surgical procedure in which a vein is used to redirect blood flow, typically in cases of arterial blockage. Collateral circulation involves the development of alternative pathways for blood flow when normal pathways are obstructed. Vein stripping is a surgical procedure to remove varicose veins and does not imply a direct connection between arterial and venous systems.