The function of veins is to return the deoxygenated blood to the heart and lungs for replenishment with oxygen that in turn is pumped through arteries to the entire body. The oxygen poor blood is carried through thin walled veins in a relatively low-pressure system to the central circulation, the heart and lungs. The flow of blood from the legs and feet would be subject to the pull of gravity in the standing and sitting position if it were not for a series of one-way valves at frequent intervals in the veins of the leg. When these venous valves are working properly, they prevent blood from rushing to the lower legs and feet whenever one’s legs are dependant as in standing or sitting. The valves, although thin and fragile, are capable of withstanding rather high pressure from the weight and volume of blood in the veins of the legs.
When the venous valves of the leg fail to close properly, blood flows away from the central circulation and towards the pull of gravity. This increased flow in the wrong direction, which we term ‘reflux’, causes elevated pressure in the veins. When this occurs in the superficial venous system of the leg, i. e. the veins between the skin and the muscle, the result over time is varicose veins. Put another way, varicose veins are the product of venous hypertension secondary to abnormal function of the venous valves. The thin-walled veins coursing beneath the surface of the skin and suffering from the elevated pressure over time become stretched and elongated and appear as ropy and tortuous bulging veins.
The prominent varicose veins may appear anywhere in the leg, but in most cases they appear in the lower leg or lower thigh. In most instances the failing valves are located well above the visible varicose veins. An ultrasound examination will usually demonstrate where the failing valves are located and therefore the source of the venous high pressure.
Symptoms of Varicose Veins
Symptoms commonly occur secondary to the venous high pressure and the varicose veins. These may include:
Fatigue and heaviness of the leg
Complications of Varicose Veins
Physical findings in addition to the prominent veins may include swelling, skin discoloration or rash, a proliferation of spider veins (telangiectasia) of the skin of the leg, ankle and feet, and the development of a sore that fails to heal and may lead to a chronic non-healing ulceration, usually at the lower leg, ankle or foot. (There are other causes of non-healing ulcers of the lower leg and foot including arterial insufficiency and diabetes. In order to avoid further serious complications a physician should evaluate all leg or foot sores that do not heal promptly.)
Another complication of varicose veins is hemorrhage. The skin overlying a varicosity may become quite thin over time, and bleeding may occur either spontaneously or with minor trauma. This may be frightening to the patient, as the bleeding may be brisk and project in a stream some distance. This appearance is the result of the high venous pressure from the failing venous valves. The bleeding is actually easily stopped by local direct pressure and elevation of the leg well above the level of the heart.
Facts About Varicose Veins:
In many patients there is a strong family history of varicose veins. If one parent has varicose veins, there is a 49% chance that the child will have varicose veins. If both parents have varicose veins, the chance jumps to 90%.
25 million Americans have varicose veins.
Varicose veins occur in both sexes with most population studies showing more women than men with the condition, however the number of men may be under-reported.
The incidence of varicose veins increases with age in men and women.
The prevalence of varicose veins has been found to be higher in industrialized developed countries than in less developed ones.
Risks factors for the development of varicose veins are family history, pregnancy, and lack of mobility, specifically prolonged standing.
Complications of venous reflux in addition to varicose veins include chronic edema, hyperpigmentation (dark discoloration of the skin of the lower leg and ankle), skin changes, bleeding from varicosities, and ulceration.
500,000 Americans suffer from painful varicose veins. Put another way, varicose veins are the product of venous ulcers of the leg, a complication of the venous reflux that causes varicose veins.The annual cost of medical care for venous ulcerations in the United States is estimated to be $1 billion.
The incidence of vascular malformations at birth is reported to be 1.2% of live births and venous malformation is the most common of these. Venous malformations may occur in any part of the body, and when they occur in the arm or leg, large varicosities, chronic swelling, and growth disturbances commonly occur.