Chronic venous insufficiency (CVI): symptoms, diagnosis, and treatment

Chronic venous insufficiency, or CVI, is a progressive vein disease affecting an estimated 6 to 7 million Americans. It develops when the valves inside leg veins fail to close properly, allowing blood to pool in the lower leg rather than returning efficiently to the heart. Left untreated, CVI advances through predictable stages and can ultimately cause painful skin changes, open wounds, and a significant reduction in quality of life.

This guide walks through what CVI is, how it develops, how it is diagnosed, and what treatment can achieve.

What is chronic venous insufficiency?

Chronic venous insufficiency is a condition where damaged vein valves fail to push blood upward effectively, causing blood to pool in the lower leg veins under sustained high pressure. It is not a single event. It is a chronic, progressive process that worsens over time without intervention.

CVI exists on a spectrum. At its mildest, it causes visible varicose veins and leg discomfort. At its most severe, it produces venous ulcers, open wounds near the ankle that can take months to heal and frequently recur without treating the underlying venous disease.

How CVI develops

Understanding the chain of cause and effect helps explain why early treatment matters so much.

1. Valve failure. The small one-way valves inside leg veins weaken or become damaged (from prior clots, genetics, or simply age and pressure). They no longer close completely.
2. Reflux (backward flow). Between heartbeats, blood that should stay in place slides backward down the leg, a process called venous reflux.
3. Blood pooling. Blood accumulates in the lower leg veins, particularly in the great saphenous vein (GSV) and small saphenous vein (SSV) systems.
4. Venous hypertension. The pooling blood creates abnormally high pressure inside the veins.
5. Fluid leakage. The increased pressure forces fluid and blood cells out through vein walls into surrounding tissue. This causes swelling and a brown-red pigment called hemosiderin that stains the skin around the ankle.
6. Tissue damage. Over time, chronically high venous pressure damages the microcirculation in the skin. Tissue becomes oxygen-deprived, prone to inflammation, and increasingly fragile.
7. When skin tissue is fragile enough, even minor trauma (or sometimes nothing at all) can trigger an open wound that the body struggles to heal because the underlying pressure problem persists.

This chain can play out over years. The early stages are very treatable with minimally invasive procedures, but many patients delay until the advanced stages, when management becomes more complex.

Where CVI fits in the bigger picture

CVI corresponds to the higher stages of vein disease, starting with persistent leg swelling and progressing through skin changes and, in advanced cases, venous ulcers. Varicose veins often coexist with CVI and may be the visible trigger that brings patients in, but CVI can also be present without prominent visible varicose veins, particularly after a prior deep vein thrombosis. For the full clinical staging framework (C0 through C6), see our guide to varicose vein stages.

Symptoms of chronic venous insufficiency

CVI symptoms tend to be worst at the end of the day and after long periods of sitting or standing, and they improve with leg elevation. That pattern is a helpful diagnostic clue.

• Heavy, tired, or aching legs, especially after long periods at a desk or on your feet
• Leg swelling that develops during the day and decreases overnight
• Burning, itching, or throbbing sensation in the lower leg
• Visible varicose veins
• Skin discoloration (brownish or reddish staining) around the ankle
• Skin that feels hard, tight, or leathery near the lower leg
• A rash or eczema-like irritation near the ankle
• An open wound near the ankle or lower leg that is slow to heal or keeps returning

How CVI is diagnosed

Diagnosis begins with a physical examination and a thorough history. The gold standard diagnostic test is the duplex ultrasound, a non-invasive exam that visualizes vein anatomy and measures blood flow direction and velocity in real time.

The duplex ultrasound evaluates:

• Which venous segments are affected (great saphenous vein, small saphenous vein, perforating veins, deep system)
• Whether reflux is present, its duration, and its severity
• Whether any deep vein obstruction (post-thrombotic disease) is contributing
• The diameter of affected vessels
• Whether perforating veins (which connect the deep and superficial systems) are incompetent

This information directly determines treatment strategy. Superficial reflux alone is treated differently from combined deep and superficial disease. A thorough ultrasound map is essential before any intervention. The ultrasound is painless and performed in our Connecticut clinics during your evaluation, with results reviewed the same day.

Treatment pathways for CVI

Treatment for CVI is tailored to the CEAP stage, the anatomy identified on ultrasound, and your overall health and goals. The approach follows a progression from conservative to interventional.

Conservative management

Graduated compression stockings (20 to 30 mmHg or 30 to 40 mmHg depending on severity) are the cornerstone of conservative CVI management. They reduce venous hypertension by supporting vein walls and improving venous return. Leg elevation, regular walking, and skin care (moisturizing to prevent breakdown) are also important.

Thermal ablation

For patients with great saphenous vein or small saphenous vein reflux, thermal ablation uses radiofrequency or laser energy delivered through a thin catheter to seal the incompetent vein closed from the inside. The body reroutes blood through healthy veins. This minimally invasive procedure is performed in-office under local anesthesia with no hospital stay required.

Sclerotherapy

After the refluxing saphenous vein is closed, residual varicose veins and feeding branches can be addressed with ultrasound-guided sclerotherapy (injection of a sclerosant solution that closes the vein). These are typically performed in follow-up sessions as part of the overall treatment plan.

Wound care for advanced CVI (C5 to C6)

Active venous ulcers require a two-pronged approach: wound care to promote healing, and vein treatment to address the underlying cause of the wound. Without treating the venous hypertension, even well-managed ulcers tend to recur. Our team is set up to manage this complex population.

Why early intervention matters

CVI progresses at different rates in different patients, but it rarely improves on its own. Each stage of progression brings more tissue damage, harder-to-reverse skin changes, and greater risk of complications. Treating CVI at C3 or C4a is far simpler, and outcomes are far better, than waiting until C6.

If you have been tolerating leg heaviness and swelling for years and attributing the symptoms to getting older or being on your feet too much, a proper evaluation can reveal a treatable underlying cause.

Ready to find out what is going on?

A duplex ultrasound at our Connecticut clinics will give you a clear picture of whether CVI is contributing to your symptoms and what your options are.

Start your evaluation today and take the next step toward healthier legs.

FAQ

Is CVI the same as varicose veins?

Not exactly. Varicose veins are often a visible sign of CVI, but CVI refers to the broader disease process: chronic valve failure leading to venous hypertension and progressive tissue damage. You can have CVI with modest-looking varicose veins, or even without visible varicose veins if the disease is primarily in the deep venous system.

Can CVI be cured?

CVI is a chronic condition. Minimally invasive treatment can close the specific failing veins identified on ultrasound, eliminate the source of reflux, and halt or significantly slow progression. Symptoms typically improve substantially. New vein issues can develop in other vessels over time, which is part of why long-term follow-up matters.

How long does it take for symptoms to improve after treatment?

Many patients notice significant improvement in leg heaviness and swelling within the first few weeks after treatment. Skin changes at C4 may improve more slowly, over months. Venous ulcers require ongoing wound care and may take weeks to months to heal completely after the underlying reflux is addressed.

Is CVI treatment covered by insurance?

CVI at CEAP C3 and above is generally considered medically necessary by most major insurance plans when supported by duplex ultrasound findings showing reflux. See our guide to when vein treatment is medically necessary.

What happens if I do not treat CVI?

Without treatment, CVI typically worsens over time. Skin changes progress, the risk of venous ulcers increases, and once an ulcer develops, it frequently recurs unless the underlying venous disease is treated. Early treatment produces the best long-term outcomes.

Can men get CVI?

Yes. While women are more frequently diagnosed, CVI affects men as well, particularly those with a family history of vein disease, history of DVT, higher body weight, or occupations involving prolonged sitting or standing. CVI in men often presents at more advanced stages because men are less likely to seek evaluation for early symptoms.