Are varicose veins dangerous?
By Dr. Bahir Hadi — Consultant Surgeon, PhD
Are varicose veins dangerous? The short answer - and when you should be concerned
"Are varicose veins dangerous?" is one of the most common questions we hear in the clinic. The short answer is: varicose veins are rarely life-threatening, but they are a chronic, progressive condition that, if left untreated, can lead to skin changes, ulcers, and in rare cases, bleeding or blood clots. Here is what you need to know - and when to take action.
The short answer
Varicose veins are a sign of chronic venous insufficiency - the valves in the veins do not close properly, causing blood to flow backwards and bulge the vein out of shape. In itself, this is not an acute condition, and most people live with varicose veins without serious consequences.
However, in a large proportion of patients, the condition progresses if left untreated and can, over a number of years, lead to:
- Chronic skin changes (pigmentation, venous eczema)
- Venous leg ulcers
- Superficial blood clots (thrombophlebitis)
- Bleeding from a ruptured varicose vein
When varicose veins require treatment
International guidelines (SVS/AVF/AVLS 2022) recommend treatment for [1]:
- C2 with symptoms: visible varicose veins + heavy legs, swelling, cramps or itching
- C3: swelling around the ankle
- C4: skin changes (pigmentation, eczema, lipodermatosclerosis)
- C5-C6: healed or active venous leg ulcers
In other words: as soon as symptoms or skin changes appear, treatment is indicated - not just for cosmetic reasons, but to prevent the condition from progressing.
The real risks of untreated varicose veins
1. Venous leg ulcers Up to 1% of adults develop venous leg ulcers [2]. These ulcers are slow to heal, recur frequently, and in Denmark cost the health service hundreds of millions. The most important preventive measure is early treatment of the underlying reflux with endovenous laser treatment (EVLT) [3].
2. Superficial thrombophlebitis A tender, red, hard vein can be a sign of phlebitis (thrombophlebitis) - a blood clot in a superficial vein. This is often benign, but in up to 25% of cases, it can develop into a deep vein thrombosis (DVT) [4].
3. Bleeding Ruptured varicose veins can bleed heavily because the pressure inside them is high. The bleeding usually stops with compression and elevation, but this is an emergency situation that requires medical attention.
4. Worsening over time Studies show that around 30% of patients with untreated C2 varicose veins progress to C3-C4 over 5-6 years [5]. Treatment halts this progression.
When are they NOT dangerous?
- Spider veins (telangiectasias) with no other symptoms
- Small varicose veins with no discomfort or skin changes
- Varicose veins during pregnancy that disappear after childbirth (read about varicose veins during pregnancy)
These cases can be monitored and, if desired, treated cosmetically with sclerotherapy.
Red flags - seek medical help immediately
Call 1813 or go to an Accident & Emergency department if you experience:
- Sudden, severe swelling in one leg with pain (suspected DVT)
- Acute shortness of breath or chest pain (possible pulmonary embolism - call 112)
- Heavy bleeding from a varicose vein that does not stop with compression
- An open sore on your leg that will not heal
- A red, warm, tender, and hard vein, accompanied by a general feeling of being unwell
What should you do now?
If you have visible varicose veins with symptoms, skin changes, or swelling, you should be assessed with a duplex ultrasound scan. The scan is painless, takes 20-30 minutes, and determines whether there is underlying reflux that requires treatment.
At Kirurgen.dk, we provide assessment and treatment under the public health service using endovenous laser treatment (EVLT). Read more about treatment of varicose veins and our prices.
References
- Gloviczki P, et al. The 2022 SVS/AVF/AVLS clinical practice guidelines for the management of varicose veins. J Vasc Surg Venous Lymphat Disord 2023;11(2):231-61.
- Nelson EA, Adderley U. Venous leg ulcers. BMJ Clin Evid 2016;2016:1902.
- Gohel MS, et al. A randomized trial of early endovenous ablation in venous ulceration (EVRA). N Engl J Med 2018;378(22):2105-14.
- Decousus H, et al. Superficial venous thrombosis and venous thromboembolism: a large, prospective epidemiologic study. Ann Intern Med 2010;152(4):218-24.
- Lee AJ, et al. Progression of varicose veins and chronic venous insufficiency in the general population in the Edinburgh Vein Study. J Vasc Surg Venous Lymphat Disord 2015;3(1):18-26.