Chronic Venous Insufficiency and Venous Stasis Explained

Chronic venous insufficiency is what happens when the valves in the leg veins stop closing properly. Blood falls back down between muscle contractions, pressure in the lower leg stays high, and over years that sustained pressure changes the tissue.

How the damage happens

Standing upright puts a long column of blood above the ankle. The leg manages it with valves and the calf pump. When valves leak, that column is no longer broken into segments, and the pressure at the ankle stays high even while you are walking. Fluid is pushed out into the tissue; red blood cells leak out too, and the iron they leave behind stains the skin brown. Inflammation follows, and eventually the skin and underlying tissue become thickened and fragile.

That is why venous disease is a slow story with a visible sequence, rather than a single event.

The usual sequence

  1. Symptoms without signs. Heaviness, aching, tiredness and restlessness in the legs, worse the longer you are upright, better after a night lying flat.
  2. Visible veins. Thread veins and varicose veins, often at the ankle first.
  3. Swelling. Soft, around the ankle, present in the evening, largely gone by morning.
  4. Skin changes. Dryness, itching, eczema-like patches, then brown or rust staining above the ankle.
  5. Hardening. The lower calf becomes firm and tight, sometimes narrowing into an inverted-champagne-bottle shape.
  6. Ulceration. A shallow, often weeping break in the skin, typically on the inner ankle, that does not close on its own.

Not everyone travels the whole sequence, and it can take decades. But the early stages are where treatment is easiest, which is the argument for taking aching legs and evening swelling seriously rather than waiting for something to break.

What causes the valves to fail

  • A previous DVT. A clot damages the valves it sits against — the resulting picture is called post-thrombotic syndrome.
  • Inherited vein wall weakness. A strong family history is common.
  • Pregnancy, through hormonal effects and increased pressure.
  • Prolonged standing, which is why certain occupations feature heavily.
  • Age and weight, both of which increase the load on the system.
  • Reduced calf pump function — a stiff ankle or limited walking means the pump does less work.

Assessment

A venous duplex ultrasound maps which veins are refluxing, how badly, and whether there is any clot. Alongside it, the arterial circulation is checked — usually with an ABI — because the answer determines whether compression is safe. That second step is not optional and is the reason this site keeps repeating it.

Treatment

Approach What it does Notes
Graduated compression Supports the veins, reduces swelling, slows skin change The backbone of management. Requires arterial assessment and correct fitting
Elevation Reduces venous pressure directly Above heart level; a footstool is not enough
Walking and ankle movement Engages the calf pump Standing still is worse than walking or sitting
Skin care Keeps fragile skin intact Emollients; prompt attention to any break
Endovenous ablation Closes a refluxing vein from the inside using heat or glue Common first-line procedure for suitable veins
Sclerotherapy Injected agent closes smaller veins Often for residual or smaller vessels
Surgery Removal or ligation of veins Less common now than endovenous options
Ulcer care Compression bandaging plus wound management Clinician-applied; not a self-management task

Closing a refluxing vein does not remove the underlying tendency, so compression and the daily habits usually continue afterwards.

Compression is not a matter of buying the strongest ones

Higher pressure is not better; it is different, and it is chosen. Too much pressure is uncomfortable enough that people stop wearing them, which is worse than a lower pressure worn every day — and in a leg with impaired arterial supply it can cause harm. Compression safety → · Fit and pressure labels →

Common questions

Is venous insufficiency the same as venous stasis?

Effectively yes. “Venous stasis” describes blood pooling in the lower leg; “chronic venous insufficiency” names the underlying valve failure. The skin changes it produces are called stasis dermatitis. They are three names circling one process.

Will it keep getting worse?

Untreated, it tends to progress slowly. Consistent compression, elevation, walking and skin care meaningfully slow that, and procedures can address the reflux driving it. The variable that predicts most is whether the compression is actually worn, which is why fit and comfort are clinical issues rather than conveniences.

Do I need my varicose veins treated?

If they are visible and causing nothing, treatment is largely cosmetic. If they come with aching, swelling, skin changes or a previous ulcer, treating the reflux has a clinical purpose. The duplex ultrasound and your symptoms together decide, not the appearance alone.

Can exercise fix it?

Exercise cannot repair a leaky valve, but the calf pump is a major part of how the leg copes, so walking and ankle exercises genuinely help symptoms and swelling. Combined with compression they do more than either alone.

Sources

  1. Society for Vascular Surgery. Chronic Venous Insufficiency.
  2. NHS. Varicose veins.
  3. NHS. Leg ulcer, and its treatment page.
  4. National Heart, Lung, and Blood Institute. Venous Thromboembolism.

Written by Tom Biernacki, DPM, FACFAS. Published 20 September 2026. General education, not medical advice.