The potential causes of varicose veins are numerous:
- Heredity: A family history of vein problems.
- Being obese or overweight.
- Routinely standing for long periods of time (at work, for example).
- Multiple pregnancies.
- Frequently engaging in heavy lifting.
Varicose veins are more commonly symptomatic for females. This is due, in part, to hormonal influences (menstruation, menopause and hormone-based drug therapy) and multiple pregnancies.
When the uterus becomes especially enlarged during pregnancy, it can push on the veins on the bones of the pelvis, and increase hydrostatic pressure in the legs. Some believe that this increased pressure, from multiple pregnancies, causes vein valves to weaken and fail.
Why Varicose Veins Develop
Our legs have two systems of veins: the deep venous system (located deep within the leg) and the superficial venous system (which lies just under the skin). Both vein systems have valves that open and close, to force blood back up toward the heart, against gravity.
When treatment for varicose veins is needed:
The valves of a healthy great saphenous vein allow blood to flow upward (above left), and stop blood from flowing to the ankles (center). However, in a diseased saphenous vein (right), these valves stop working properly. Blood flow builds up in veins that drain into the saphenous vein, causing these tributary veins to swell and become varicose veins. Malfunctioning saphenous vein valves also allow blood to pool in the calf and ankles, rather than force blood flow back to the heart.
The deep system has very strong, hearty valves. However, the superficial venous system — particularly the great saphenous vein, located in the inner thigh — is much more prone to chronic venous insufficiency.
Because the great saphenous vein must propel blood upward — against gravity — to the heart, it relies heavily on its valves to prevent the backward flow of blood down the vein. When a valve in the saphenous vein fails, blood is allowed to "leak" toward the ankles. Blood is not sent back to the heart.
In turn, blood pools in the lower legs, in the smaller superficial veins that drain into the saphenous vein. Pressure builds in these superficial veins — they become painful and swollen (resulting in varicose veins). Blood can pool around the ankles and calf, resulting in a swelling, discoloration and a persistent, dull ache that is characterized by leg heaviness.
When treatment is needed, a John C. Lincoln physician will address the great saphenous vein using radiofrequency ablation first. If a "leak" in the saphenous veins is not treated first, varicose veins will continue to develop in other areas of the affected leg.