Varicose veins. The facts.
A lot of inaccurate information on websites has led to confusion about veins among doctors and patients. This is a useful summary of proven facts. If you would like more detailed information then we suggest you visit the College of Phlebology website.
1. How do veins work?
Two types of blood vessels
Arteries carry blood containing oxygen from the heart ( and lungs ) to all parts of the body. They are under higher pressure and they pulsate.
Veins are the vessels that bring blood back to the heart and lungs. They are under lower pressure, but have to overcome gravity.
How does blood flow against gravity?
Blood in the legs has to overcome gravity to rise to the heart, particularly when standing. Inside veins there are one-way / non-return valves, which open with forward flow to allow blood back to the heart. Backward pressure will close the valves to prevent reversed flow ( reflux ). When your leg muscles contract during active movement blood is pumped upwards in your leg veins. This is followed by closure of the vein valves during muscle relaxation which prevents reversal of flow of the blood ( venous reflux ). These non-return one-way valves ensure that the blood will only flow towards your heart and against the effect of gravity.
Deep and superficial veins of the legs
There are two parallel routes for blood to flow up. Blood in deep veins inside muscles is squeezed forward by muscular activity, drawing in blood from more superficial veins just under the skin. Both sets of veins are connected by perforator veins at points going up the leg. There are two main superficial veins, one draining to the back of the knee ( small saphenous vein ), the other reaching the groin and connecting to the deep vein here ( great saphenous vein ).
2. What causes varicose veins?
Superficial veins have multiple valves along their course. The most important are located just before their connections with the deep veins at the groin and behind the knee. Valves can become damaged and go floppy. Normal flow ceases and reversed flow ( venous reflux ) occurs back along the vein. Then blood will pool under pressure lower down. This causes the superficial vein to enlarge and become twisted ( varicose ). This causes a state of venous insufficiency and the veins are said to be incompetent.
- Valve failure: this is often hereditary, but the genetics is unclear as only some offspring get varicose veins and often only one leg is affected
- Muscle pump failure : e.g in immobile people e.g. after a stroke, but is commonly associated with prolonged standing although this does not cause varicose veins
- Deep vein thrombosis can cause deep vein blockage , but may also cause permanent damage to both deep and superficial vein valves
- Multiple pregnancies, obesity and older age are all contributing factors to pre-existing vein valve failure but they do not cause varicose veins.
Up to 40% of the adult population get superficial valve failure. Reflux of blood in the incompetent vein may show up only as thread veins or spider veins. The concept of venous incompetence acting as “hidden varicose veins” is a useful one. Only with accurate Doppler ultrasound scanning can this be diagnosed. When varicose veins become visible there will be an on-going process over time for these to enlarge and progress. The unpreventable reversed blood flow will cause inflammation in the vein walls and local leakage of fluid causing aching and swollen ankles. The inflammation may progress further with more fluid leaking into the surrounding soft tissues causing skin changes that become varicose eczema. And in some cases this will progress to venous leg ulcers at the ankle.
It is our policy to do a detailed Doppler ultrasound scan on all new patients at their first assessment. This will diagnose any hidden varicose vein reflux which is essential to know before planning vein treatment, even if it is only an unsightly thread vein.
3. Common myths about varicose veins
- Excess weight does not cause varicose veins: Again any pelvic pressure effect is tolerated with normal valves. Over-weight people are less active and inactivity actually increases the risk of deep vein thrombosis ( DVT ). Taking more exercise will however improve the muscle pump efficiency of the legs.
- Crossing your legs does not cause varicose veins !
- Constipation and straining does not cause varicose veins : it may be responsible for haemorrhoids, but these are in a completely separate part of your blood circulation.
- Hot baths and hotter climates do not cause varicose veins : veins normally dilate with heat as a normal cooling mechanism and contract on cooling. There is no difference in prevalence of varicose veins between different countries.
- Varicose veins are only cosmetic : Untrue. This is a common statement by uninformed doctors ( and Insurance companies ) to put people off having anything done. GP’s know that varicose vein surgery has had poor results and high rates of recurrence. What they may not know is that modern non-surgical varicose vein treatments by a vein specialist are highly effective at curing the patients symptoms.
- Varicose veins should only be treated when they are painful : The majority of people with even small varicose veins will have tired legs or some ankle swelling at some point. Hidden varicose vein reflux will cause aching without visible veins and pain may occur only if the veins become inflamed. The NHS has very strict criteria to decide who will be operated on; this includes bleeding veins, active/recurrent inflammation ( thrombophlebitis ) and leg ulcers. The vast majority of sufferers will not fit these criteria and are therefore consistently refused any treatment at all.
- Stockings will cure varicose veins : Untrue. Specially fitted graduated compression hosiery will help to heal leg vein ulcers. In uncomplicated varicose veins they only flatten the distended veins and cannot repair the faulty valves. They are very useful to reduce ankle swelling and bruising especially for a few weeks after non-surgical vein treatments.
- After varicose vein surgery or key-hole treatment there is more strain on the deep veins : Untrue. There is actually improved muscle pump efficiency, with less stagnation of blood in superficial veins and improved flow to the deep veins via perforators veins.
- Herbal medicine can cure varicose veins: Untrue. There are claims that butchers broom, St John’s wort, witch hazel and lavender can “tighten” varicose veins. They may have a mild local anti-inflammatory effect on phlebitic veins ( less than ibuprofen ointment ) but like everything else they cannot repair faulty vein valves. Extract of horse chestnut seed has some claim to alleviating symptoms of varicose veins.
- Varicose veins are more common in women : Untrue. Both sexes are equally susceptible to have vein valve malfunction. Women present earlier because they are more health and body conscious. Their pre-existing hidden tendency to develop weak vein valves is tested during pregnancy. With multiple births the progression of venous incompetence is accelerated ( see below; varicose veins in pregnancy) By the time both sexes reach 65 years, there are equal numbers of complicated varicose vein sufferers. Men actually have a higher incidence of venous ulcers as they get older, possibly due to neglect to get treatment at an earlier age.
4. Varicose veins in pregnancy
“DON’T BLAME YOUR CHILDREN, BLAME YOUR PARENTS !”
There is a very common misconception that pregnancy causes varicose veins. If you have read any information above, you will know that both men and women are at equal genetic risk of developing hidden faulty valve venous reflux. If there was a direct pressure effect of the baby in the womb on the pelvic veins, then there would be a lot more deep vein thrombosis seen in pregnant women. During the last third of pregnancy the total blood volume in the woman’s body has increased by 40%, which causes significant distension of the leg veins. There are also high levels of the natural pregnancy hormone progesterone which causes loosening of the soft tissues and changes in collagen in preparation for delivery. If a lady has already got hidden vein reflux, possibly passed on from her parents, then varicose veins may appear for the first time. Quite often they will almost completely disappear a few months after birth. With more children comes an accumulating effect on the vein valves and the varicose veins then stay permanently. For this reason we never ever do vein treatments of any type during pregnancy.
Because old-fashioned traditional vein surgery has had such a bad reputation for recurrence many doctors advise ladies to wait until they have had all their family before considering surgery. Non-surgical heat ablation varicose vein closure techniques have consistently low long-term recurrence rates, so we can now completely knock this argument on the head.
If you already have even mild varicose veins, then consider having non-surgical vein treatment by a trained specialist BEFORE YOU START YOUR FAMILY.
By adopting this strategy, you will save yourself a lot of discomfort and immobility during your first and all subsequent pregnancies. Varicose veins of the vulva may become very uncomfortable during late pregnancy, but will usually resolve. They are caused by incompetent vein valves too, but these are inside the abdomen in the veins draining the two ovaries. This is exacerbated by some pressure effect from the womb. If vulval varices persist after pregnancy then we would advise that you have them investigated by Doppler ultrasound and possibly other scan tests e.g. MRI. Ovarian vein incompetence is very treatable by interventional radiological techniques called embolization, which blocks both veins with small metal coils. This treatment is available in the NHS if you see a specialist for diagnosis. Not all obstetricians are aware of how easy and effective ovarian vein embolization can be. Dr McBride is an experienced Interventional Radiologist and has much experience and a special interest in this condition. He feels that not enough women are being sent for investigation and are missing out on this effective treatment. This condition is also responsible for a significant proportion of patients having recurrence of their previously treated leg varicose veins.
5. Why do varicose veins recur ?
“Traditional” varicose vein surgery involves cutting at the groin and cutting below the knee before pulling the entire length of the superficial vein out of the thigh under general anaesthetic. This is usually accompanied by multiple small 1cm cuts below the knee to pull out fragments of twisted vein. Obvious complications include wound infection, nerve damage, haematoma and deep vein thrombosis. Minor and major complications can occur in up to 30% of operations.
Subsequent recover is usually good, but the patient is left with multiple scars, some of which become more unsightly with time as spider veins develop around them. The BIG PROBLEM with surgery is the very high recurrence rate. At 3 years this is 30% and at 5 years this is 50% !
The most obvious reason for veins coming back is that they were not taken away in the first place ! All vein surgeons should now have a policy of mandatory Doppler ultrasound to fully diagnose the reflux problem before attempting vein removal.
There is now very good scientific evidence to show that the veins at the groin and along the inner thigh can grow back, even commencing within 12 months of the operation, in up to 1 in 4 cases. It seems that the cutting of the vein with exposure of the raw stump and side branches which sit within haematoma are stimulated immediately to produce new veins. Therefore surgery stimulates recurrence.
The new “inside-the-vein” endovenous techniques which use heat ( thermal ablation ) to shrink down the varicose vein and close it are now showing very low recurrence rates at 5 and 7 years. There appears to be very little new vein growth particularly at the groin. This is borne out by the experience at the Scottish Vein Centre, where we have treated over 300 incompetent veins by endovenous laser ablation ( EVLA ) over the past 6 years and we have yet to see any recurrent cases.
Some of our patients will return for more local treatment of varicose vein tributaries on their calves which respond well to injection sclerotherapy. This is not recurrence but new incompetent vein formation. The genetic tendency to develop faulty vein valves continues through life, albeit these are usually minor problems and are easily treated. We have had excellent proven patient satisfaction for long term results.
Patients who are still suffering from varicose veins after they have had vein surgery will definitely benefit from having a detailed Doppler ultrasound scan to determine why their varicose veins have returned. We have had brilliant results using either a combination of EVLA and ultrasound-guided foam sclerotherapy ( UGFS ) or with UGFS alone to treat recurrent varicose veins at the Scottish Vein Centre. In the last 30 patients with recurrent varicose veins we have had complete clinical success with no evidence of re-growth in those we re-scanned This compares with a dismal 70% re-recurrence rate for repeat vein surgery.