Varicose veins are veins that have become swollen enough to be seen on the legs. This condition affects the superficial veins, which lie closest to the skin. The affected veins appear as blue bulging, twisted lumps under the skin. Varicose veins are commonly found among people who stand on their feet a lot. It’s a condition that can run in the family and affects as many as 20 million Americans.
Varicose veins appear when excess blood pools in the superficial veins of the leg. Sitting or standing for long periods of time can cause this to happen, increasing the pressure on the vein walls. This pressure stretches the vein itself, weakening the one-way internal valves in the vein that open to let blood flow through and shut to keep blood from flowing backward. When these valves are weakened or damaged, blood can back up and pool in your veins, causing them to swell.
Similar to varicose veins seen with superficial veins, chronic venous insufficiency (CVI) is a condition that occurs when blood pools in the superficial and deep leg veins. CVI can occur with or without the presence of varicose veins. This condition develops when the blood pressure in the veins is abnormally high. CVI can occur after veins have been damaged by injuries or blood clots. People with CVI often have a combination of symptoms.