Clinic Locations
Advertising

varicose vein causes

 

Many theories exist for why varicosities occur in veins, but the general consensus amongst clinicians and researchers is that defective or damaged valves within the veins are to blame.

Varicose veins develop from the superficial system of veins and are usually a result of a problem from the great saphenous vein (running from the groin to the ankle) although it is not uncommon for the small saphenous vein (running from behind the knee to the ankle) to be the problem.

Varicose veins are tortuous, dilated  veins; where the valves have failed, allowing increased flow of blood back down the veins.

Valve failureThe simple leaflet valves with in the vein are designed to prevent backward flow of blood within the vein. They keep blood in the vein moving toward the heart. Why the valves stop working is up for debate.

Some experts think inherited problems cause some people to have too few valves or valves that do not function properly. Some people may be born with abnormalities of the vein wall. The resulting weakness may predispose the valve leaflets to separate and become leaky.

When the muscles surrounding the deep veins contract, emptying the deeper veins, a build-up of pressure occurs. This causes even more blood to go the wrong way from the deep to the superficial veins through faulty valves in the perforator veins.

The result is that when a person with poorly functioning valves stands up, the blood flow actually reverses and flows down the superficial veins, when it should be flowing up, toward the heart.

This increases pressure in the superficial veins results in their enlargement. As the vein becomes bigger the wall of the vein stretches in length and width and becomes tortuous. As the condition progresses and the veins become further dilated large sacs can appear at the bends of the veins and the blood flow at these points becomes turbulent (disturbed) and can become stagnant. This stagnation of flow can result in the vein becoming blocked or thrombosed, called superficial thrombophlebitis.

This does not occur in all cases and often varicose veins can just be unsightly; and indeed some people get no further problems with their veins other than the appearance. Unfortunately there are many that do suffer from further symptoms associated with varicose veins such as aching.
 
Truncal VaricositiesThe symptoms caused by incompetent veins are, in fact, very variable. Small varicosities and dermal flares may cause only cosmetic complaints. However, larger varicosities may cause pain in the legs. Patients who suffer deep vein thrombosis may experience swelling of the limb. Patients with severe venous valvular incompetence my suffer ulceration of the leg.

The pain associated with varicose veins is thought to be as a result of the stretching a muscle coat. Veins and arteries are made of a smooth muscle (muscle coat) which is responsible for keeping the tension in the blood vessel.

While the causes of varicose veins may still not be fully understood, there is general agreement on many of the factors that can aggravate the situation.
Pregnancy is associated with an increase in blood volume. Also, added pressure on the veins in the legs by the weight of the growing uterus and the relaxation effects of the hormones oestrogen and progesterone on the vein walls contribute to the development of varicose veins during pregnancy.
Prolonged standing
Obesity or distended abdomen
Straining: Chronic constipation, urinary retention from an enlarged prostate, chronic cough, or any other conditions that cause you to strain for prolonged periods of time causes an increase in the forces transmitted to the leg veins and may result in varicose veins. These mechanisms also contribute to the formation of haemorrhoids, which are varicosities located in the rectal and anal area.
Prior surgery or trauma to the leg: These conditions interrupt the normal blood flow channels.
Age: Generally, most elderly individuals show some degree of varicose vein occurrence.

 

 

 

 Continue here to read about the Myths surrounding Varicose Veins