Venous Insufficiency


What is chronic venous insufficiency?

Arteries bring oxygen-rich blood from your heart to the rest of your body. Veins return oxygen-poor blood back to your heart. When your leg veins cannot pump enough blood back to your heart, you have chronic venous insufficiency. It is also sometimes called chronic venous disease. You have three kinds of veins, superficial veins, which lie close to the skin, and deep veins, which lie in groups of muscles. Deep veins lead to the vena cava, your body's largest vein, which runs directly to your heart. Perforating veins connect the superficial to the deep veins.

The blood in your leg veins must go against gravity to return to your heart. Your leg muscles squeeze the deep veins of your legs and feet to help move blood back to your heart. One-way flaps called valves in your veins keep blood flowing in the right direction. When your leg muscles relax, the valves inside your veins close. This prevents blood from flowing backward. The entire process of sending blood back to the heart is called the venous pump.

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When you walk and your leg muscles squeeze, the venous pump works well. But when you sit or stand, especially for a long time, the blood in your leg veins can pool and increase blood pressure. Deep veins and perforating veins are usually able to withstand short periods of increased pressures. But sitting or standing for a long time can stretch vein walls because they are flexible. Over time, in susceptible individuals, this can weaken the walls of the veins and damage the vein valves, causing chronic venous insufficiency.

What are the symptoms?

If you have chronic venous insufficiency, your ankles may swell and your calves may feel tight. Your legs may also feel heavy, tired, restless, or achy. You may feel pain while walking or shortly after stopping.

Chronic venous insufficiency may be associated with varicose veins. Varicose veins are swollen veins that you can see through the skin. They often look blue, bulging, and twisted. Large varicose veins can lead to skin changes like rashes, redness, and sores.

Chronic venous insufficiency can also cause problems with leg swelling because of the pressure of the blood pooling in the veins. Your lymphatic system may also produce more of a fluid called lymph to compensate for chronic venous insufficiency. Your leg tissues may then absorb some of this fluid, which can increase the tendency for your legs to swell.

What causes Chronic Venous Insufficiency?

Long-term high blood pressure inside your leg veins causes chronic venous insufficiency. Other causes of chronic venous insufficiency include deep vein thrombosis (DVT) and phlebitis.

Deep vein thrombosis occurs when a blood clot (called a thrombus) blocks blood from flowing out of a deep or perforating vein. Blocked veins can increase vein blood pressure, which overloads your valves. Vein valves that do not work properly are called incompetent, and incompetent valves contribute to chronic venous insufficiency. Deep vein thrombosis is a potentially serious condition that causes leg swelling and requires immediate medical attention because sometimes the blood clots in the veins can break off and travel to the lungs. This condition is called a pulmonary embolus.

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Phlebitis occurs when a superficial vein becomes swollen and inflamed. This causes a blood clot to form (thrombophlebitis), which can also cause deep vein thrombosis.

Factors that can increase your risk for chronic venous insufficiency include a family history of varicose veins, being overweight, being pregnant, not exercising enough, smoking, and standing or sitting for long periods of time. Your age and gender can also increase your risk of developing chronic venous insufficiency; patients older than 50 most often get chronic venous insufficiency.

What tests will I need?

First Dr Weir will ask you questions about your current general health, past medical history, and symptoms. In addition, he will conduct a physical exam. Together these are known as a patient history and exam. Dr Weir may measure the blood pressure in your legs and will examine the varicose veins. To confirm a diagnosis of chronic venous insufficiency, Dr Weir may order a duplex ultrasound test.

Duplex ultrasound uses sound waves higher than human hearing can detect. Duplex ultrasound allows your physician to measure the speed of blood flow and to see the structure of your leg veins.

How is Chronic Venous Insufficiency treated?

Chronic venous insufficiency is not considered a serious health risk. Dr Weir will focus his treatment on decreasing your pain and disability.

Compression Stockings

For all cases of chronic venous insufficiency, Dr Weir will recommend compression stockings. Compression stockings are elastic stockings that squeeze your veins and stop excess blood from flowing backward. In this way, compression stockings can often also help heal skin ulcers and prevent them from returning. You have to wear compression stockings daily for the rest of your life.

You can help avoid leg swelling and other symptoms by occasionally raising your legs and avoiding standing for long periods of time to decrease the pressure in the veins. When you do need to stand for a long period, you can flex your leg muscles occasionally to keep blood flowing.

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Fewer than 5 per cent of people with chronic venous insufficiency require surgery or endovascular intervention to correct the problem. Surgical treatments include vein stripping, bypass surgery, and valve repair.

Vein Stripping

To perform vein stripping, Dr Weir first makes a small incision in the groin area. Then he disconnects and ties off all veins associated with the saphenous vein, the main superficial vein in your leg. He then removes this vein from your leg. A procedure called ambulatory phlebectomy or small incision avulsion can be done alone or together with vein stripping. Small incision avulsion allows Dr Weir to remove varicose veins from the leg through tiny incisions.

Bypass

For more extensive problems, a vascular surgeon can perform bypass surgery to treat chronic venous insufficiency that occurs in the upper thigh. For example, the surgeon can connect an artificial or transplanted vein, called a graft, to a vein affected by chronic venous insufficiency to help blood flow from the affected leg. Most vein surgery can be performed through small incisions. Usually bypass surgery is safe, although there is a risk of deep vein thrombosis and infection at incision points. Dr Weir will only recommend this procedure in the most serious instances, where all conservative measures have failed.

Endovascular Venous Procedures

For patients who suffered extensive iliac deep vein thrombosis, a select few might benefit from catheterisation of the affected veins with venoplasty and stenting of the affected veins in an attempt to reduce the resistance against flow of blood back to the heart.

Valve Repair

In valve repair, a surgeon shortens the valves inside the vein to improve valve function. After making a small incision into the skin, the surgeon cuts into the affected vein. The surgeon then folds or tucks the valve flaps. He may place a fabric sleeve around the outside of the affected vein to help press the walls of the vein together to maintain valve function. Unfortunately this procedure is controversial due to the low success rate.

Vascular and Hyperbaric Unit, Eugene Marais Hospital, Pretoria, South Africa (012) 335 8651