What is the definition or description of: venous insufficiency?

CVI: Venous insufficiency is described as the reduced ability of the veins to provide an adequate return of blood back to the heart from the lower extremities. The fault typically is with the walls and/or the valves located in the veins of the legs. The failing valves allow a back flow of blood which increase the pressure on the vein walls thus resulting with varying degrees of pedal edema.

Venous insufficiency: Venous insufficiency can be due to malfunctioning of the superficial or deep venous system of valves and is called superficial or deep venous insufficiency depending on the valves involved.There can also be a combination of both systems Varicose veins and DVT cab both lead to venous insufficiency. Signs of venous insufficiency include leg and ankle swelling and brownish discoloration of the legs.