This Publication Is Searchable The Merck Manual of Diagnosis and Therapy Section 16. Cardiovascular Disorders Chapter 212. Etiology Varicose veins are associated with valvular dysfunction. A family history is common.
Some experts believe that valve incompetence is the cause of varicose veins.
It is theorized that valve failure at the saphenofemoral junction permits reflux into the saphenous vein, resulting in descending sequential valvular incompetence from the thigh to the calf. The concept of ligation of the long saphenous vein at the groin and stripping of the long saphenous vein, with or without the short saphenous vein, is based on this theory. If valve incompetence were the major factor, new varicose veins should not develop. A contrasting theory is that one or more perforator veins in the lower leg result in high-pressure flow and increased volume from deep to superficial veins during muscular contraction. In time, superficial veins become dilated, separation of the valve cusps prevents their apposition, and flow reverses in the affected veins.