What is endovenous thermal ablation (EVTA)?
EVTA is a minimally invasive surgical procedure performed to treat varicose veins. It involves destruction of the affected vein from within using heat energy. One of the two sources of heat may be used: radiofrequency (RF) heat or laser energy. When a laser is used for EVTA, it is termed as endovenous laser ablation (EVLA) or EVLT (endovenous laser therapy).
When is EVTA indicated?
EVTA is indicated as an interventional treatment for longer varicose veins with larger diameter veins. EVTA is considered to be safe for most patients. However, NICE guidelines suggest that it is contraindicated in pregnant women.
How does this procedure treat varicose veins?
EVTA treats the root cause of varicosity, which is the incompetent vein that has a backflow of venous blood. The entire vein is therefore destroyed by using laser energy/RF heat. This procedure is called ‘closure procedure’. The laser energy burns the inner layer of the vein from the inside such that it shrinks and becomes thin and loses its patency. The old method involved stripping of the whole vein, which leaves behind a scar, creating cosmetic concerns. EVTA does not leave a scar as it involves entering the sheath though a tiny hole in the skin.
Picture source: http://venacure-evlt.com/varicose-veins/treatments/RF-ablation/
How is EVTA performed?
- A catheter is threaded into the affected vein through a tiny hole near the knee or ankle under ultrasound guidance.
- A long sheath is passed into the vein tracing it up to the saphenous junction. This sheath is a thin tube that envelops the superfine laser fibre in position.
- Duplex ultrasound is used to visualise and position the end of the sheath exactly at the junction.
- ‘Tumescent anaesthesia’ is administered guided by ultrasound to ensure that the fluid is in the right place.
- The vein is now swollen, firm, and partially straightened out.
- Once the tumescent anaesthesia has been infiltrated, the laser fibre is passed inside the sheath until it exits from the top. The fibre is fixed to the sheath and the laser/RF heat is switched on.
- The vein is destroyed while the sheath and the laser fibre are pulled back at a controlled rate.
- Tumescent anaesthesia ensures that the surrounding tissue is not burnt; at the same time, the vein that has to be ablated is destroyed completely.
There may be minor variations to the technique mentioned above, but fundamentals remain the same.
Is the procedure painful?
While everyone experiences pain differently and there is no perfect answer to this question, we can say that the procedure by itself is not painful. After the vein shrinks in size and shuts, a sensation of tightness might be experienced that might last up to 1-2 months. Some patients might also experience a numbness or tingling sensation. This is temporary and resolves on its own in a few weeks.