Thermal procedures for the treatment of varicose veins

Minimally invasive endovenous procedures include endovenous laser therapy (EVLT), endovenous radiofrequency ablation, and foam sclerotherapy.
For EVLT and radiofrequency ablation, a catheter is introduced into the varicose vein under ultrasound guidance. The varicose veins are ‘cooked’ or coagulated from the inside using laser light or radio waves. As the vein is occluded by the effect of the heat, these two methods of treatment are designated as thermal procedures. They have become increasingly important in recent years and are now well established in the treatment of trunk varicose veins. As different methods are recommended for all the other types of varicose veins, thermal procedures are usually combined with other methods – when side branch veins are affected as well as the trunk veins, for instance.

Depending on the duration and intensity of exposure, the thermal effects range from slight warmth to carbonisation of the tissue. State-of-the-art devices and the routine protective measures largely prevent unwanted thermal damage and burns. Treatment can be performed as an outpatient (ambulatory) procedure and does not need a general anaesthetic. Instead, tumescent anaesthesia (a special form of local anaesthesia) is used.

One big disadvantage of thermal procedures is their cost: one treatments session costs around 1500 EUR.
The catheters and equipment used for thermal procedures are medical devices and not medicinal products like sclerosants.

Advantages and disadvantages of thermal procedures at a glance

How thermal procedures work

Laser beams are electromagnetic waves; depending on the duration and intensity of exposure, the thermal effects range from slight warmth to carbonisation of the tissue.

When a laser beam is introduced into the vein via a special catheter, the haemoglobin (which gives the blood its red colour) absorbs the laser light and converts this energy into heat. The blood is sort of boiled and clots. The thermal effects damage the inner layer of the vein walls and cause them to stick together. In the ideal case, a connective tissue strand forms over time, which is then resorbed into the body after a few weeks.

Radiofrequency ablation is similar to laser therapy. Here too, a catheter is introduced into the varicose vein, although in this case radio waves are emitted via the tip. This energy is also converted into heat. Compared with laser therapy, radiofrequency ablation is gentler, but here too temperatures around 100 degrees Celsius are reached in order to burn the vein.

Success rate of thermal procedures

Numerous clinical studies have shown that thermal procedures are effective in the treatment of trunk veins and despite the costs many doctors consider them the treatment of choice for varicose veins of this type. As a rule, trunk varicose veins can be occluded in a single treatment session. Laser therapy and radiofrequency ablation compete with surgical procedures and the less invasive foam sclerotherapy in the treatment of trunk varicose veins.

The side branch varicose veins that often accompany trunk vein disease are usually treated with other methods. As it is very difficult to push a catheter along a very tortuous varicose vein (as is often the case with side branch veins) without damaging it, other methods are more suitable in these cases.

A recent analysis of all the studies found in the literature showed that the clinical results of thermal procedures, surgery, and foam sclerotherapy are all comparable. In conclusion, it can be said that all these methods of treatment are similarly effective and safe in treating large varicose veins.

The recently issued National Institute for Health and Care Excellence (NICE) guideline is mainly concerned with the diagnosis and treatment of trunk varicose veins. According to the guidelines, thermal procedures, foam sclerotherapy, and surgical procedures are all therapeutic options. No significant differences have been found between these procedures in the decisive criteria on efficacy. Thermal procedures are in the lead with respect to the reduction in backwards blood flow (reflux) after 3 weeks. Taking the side effect of ‘pain after the procedure’ into account, foam sclerotherapy has the advantage. Overall, the authors’ appraisal of the thermal methods in the treatment of trunk varicose veins is slightly more positive, although sclerotherapy remains the most cost-effective of all the methods.
According to the guideline, surgical procedures should be offered only if foam sclerotherapy is not possible. The higher rate of nerve injury after surgery was considered clinically relevant.

Compression therapy should be used for a few weeks after treatment, irrespective of the method used.

When are thermal procedures not possible?

Thermal procedures must not be used

• if you have severe peripheral arterial occlusive disease (a disorder of the arterial circulation in the legs).
• if you have an acute inflammation of the veins (phlebitis).
• if you have a deep vein thrombosis or pulmonary embolism.
• if you are currently suffering from severe systemic disease (for example, acute leukaemia or acute liver insufficiency).
• if you are allergic to the anaesthetic agent to be used.
• if you have an acute infection in the area of the incision.
• if the varicose veins to be treated are very tortuous.

Special care is also required if you have a high risk of thrombosis. This is, for example, the case if you have an inherited tendency to thrombosis (thrombophilia) or if you have to lie in bed with a plaster cast for a long time after an injury.

Your doctor will discuss with you any other illnesses that have to be considered.

If there is any possibility that you could be pregnant at the present time, you must tell your doctor about this without fail before starting treatment.

How thermal procedures are carried out

You can basically have treatment at any time of the year but, as with other methods of treatment, it is best not to start just before going away on holiday; treatment sessions should be completed not less than 2-3 weeks before going on a longer trip.

After a thorough examination and diagnosis, which is a decisive factor for treatment success, your doctor will draw up a treatment plan for you and explain exactly how treatment will be carried out and provide information on the possible risks and chances of success.

Treatment is usually carried out on an outpatient basis and always with the patient lying down. The area of skin to be treated will be disinfected and a local anaesthetic may be injected before a small incision is made in the skin to allow the insertion of a catheter. The catheter is put into the diseased vein around the ankle or in the lower leg under ultrasound guidance and positioned precisely. Depending on the method to be used, either laser beams are emitted from laser fibres or radio waves are emitted from the catheter tip and the vein is closed off step by step while continuously pulling back the catheter. The heat energy obtained in effect burns the diseased vein.

Before heat is applied to the vein, the surrounding tissues are protected with tumescent anaesthesia. This is a special type of local anaesthesia, in which a large volume of fluid (300 mL) is injected into the subcutaneous tissue under pressure. Tumescent anaesthesia provides a wide area of anaesthesia around the veins to be treated and affords protection from pain. In addition, the large volume of fluid in the tissues acts as a sort of firewall, preventing heat being transmitted into the surrounding tissues and damaging nerves and other tissues. Burns and scarring may occur if the tissues are not adequately protected, as radio waves generate temperatures of 100-120 degrees Celsius and laser beams up to as high as 1000 degrees Celsius.
As with any clinical use of laser energy, safety precautions have to be maintained to protect both the patient and medical staff (e.g. laser protective goggles).

As a rule, 2 follow-up appointments are made – one 1-2 weeks after treatment and another 3-6 months later. After the procedure, patients should wear compression stockings or compression bandages for a few weeks.

After treatment

• As with all endovenous methods, the result cannot be seen immediately after treatment. It may be several weeks before your body has broken down the diseased veins.
• After treatment, you should walk briskly for 20-30 minutes each day to activate the blood flow through the veins.
• You should wear a compression stocking or bandage for a few weeks after treatment.
• You can go back to work fairly soon after the procedure.
• You are advised not to take part in any strenuous sporting activities (intensive jogging, long mountain hikes, or football) for the first 2 two weeks after treatment.
• After treatment, avoid the sauna, long hot baths or showers, solaria, or prolonged sunbathing. It is difficult to give a precise length of time, so you should rely on the experience and recommendations of the doctor treating you.
• Do not plan any long journeys by bus, train, or car in the first 2 weeks after treatment and, in particular, avoid long-haul flights.
• Contact your doctor without delay if you notice anything untoward or the leg is very painful.
• Please be sure to attend the follow-up examinations.

Risks of laser and radiofrequency ablation therapy

Although thermal procedures are safe methods of treatment, they may have unwanted side effects. Both the treatment itself and the injections for the tumescent anaesthesia may cause bruising, haematomas, and temporary discolouration around the site of the treated varicose veins, although these changes usually resolve soon after treatment. The pain experienced after treatment occurs to a greater or lesser extent. Routine administration of a painkiller (analgesic) after treatment is not recommended and medication is only prescribed for use when necessary. In addition, there may be temporary hardening and inflammation around the treated vein.

The risk of nerve damage increases the further down the leg is treated and the risk of burning the skin must always be mentioned. Subsequent bleeding and wound infections are less likely than with surgical procedures, as no large incisions are made in the skin. Deep vein thrombosis occurs in rare cases. Very rare side effects that may also occur are, for example, systemic allergies or circulatory reactions to the local anaesthetic agent used (lidocaine, adrenaline).

Before you start treatment, your doctor will explain the possible side effects to you and answer any questions that you may have.