Overview
The Venous-Pressure Problem
Varicose veins are enlarged, elongated, and twisted superficial veins caused by weakness of the vein wall and failure of venous valves.
Varicose veins are enlarged, elongated, and twisted superficial veins caused by weakness of the vein wall and failure of venous valves. Normally, valves open to let blood move toward the heart and close to prevent backward flow. When they become incompetent, blood refluxes—especially while the patient is standing—and ambulatory venous pressure rises in the lower leg. That sustained pressure stretches superficial veins until they become visibly tortuous. Prolonged standing or sitting worsens symptoms because gravity increases the column of blood below the incompetent valves. Walking activates the calf-muscle pump and helps propel blood upward; elevation reduces the hydrostatic pressure in the leg. Risk increases with age, pregnancy, overweight or obesity, physical inactivity, prolonged standing or sitting, and family history. Varicose veins may begin as an appearance concern, but persistent venous hypertension can produce aching, heaviness, itching, edema, inflammation, skin breakdown, superficial vein thrombosis, and bleeding.