Chronic Venous Insufficiency and Post-Thrombotic Syndrome

ByJames D. Douketis, MD, McMaster University
Reviewed/Revised Dec 2023
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Chronic venous insufficiency is impaired venous return, sometimes causing lower extremity discomfort, edema, and skin changes. Post-thrombotic (postphlebitic ) syndrome is symptomatic chronic venous insufficiency after deep venous thrombosis (DVT). Causes of chronic venous insufficiency are disorders that result in venous hypertension, usually through venous damage or incompetence of venous valves, as occurs (for example) after DVT. Diagnosis is by history, physical examination, and duplex ultrasonography. Treatment is compression, wound care, and, rarely, surgery. Prevention requires adequate treatment of DVT and compression stockings.

Prevalence estimates of chronic venous insufficiency vary widely, reflecting differences in the study populations (1). Post-thrombotic syndrome may affect up to 50% of patients with deep venous thrombosis (DVT), and can have a substantial effect on quality of life. Post-thrombotic syndrome can range in severity from mild leg swelling to debilitating venous leg ulcers; 20 to 35% of patients will develop moderate to severe disease. Post-thrombotic syndrome is more common in patients with more extensive DVT, such as those with involvement of the common femoral and/or iliofemoral veins (2).

General references

  1. 1. Galanaud JP, Monreal M, Kahn SR. Epidemiology of the post-thrombotic syndrome. Thromb Res 2018;164:100-109. doi:10.1016/j.thromres.2017.07.026

  2. 2. Rabinovich A, Kahn SR. How I treat the postthrombotic syndrome. Blood 2018;131(20):2215-2222. doi:10.1182/blood-2018-01-785956

Etiology of Chronic Venous Insufficiency

Venous return from the lower extremities relies on contraction of calf muscles to push blood from intramuscular (soleal) sinusoids and gastrocnemius veins into and through deep veins. Venous valves direct blood proximally to the heart. Chronic venous insufficiency occurs when venous obstruction (eg, in DVT), venous valvular insufficiency, or decreased contraction of muscles surrounding the veins (eg, due to immobility) decrease forward venous flow and increase venous pressure (venous hypertension).

Fluid accumulation in the lower extremities (eg, in right heart failure) can also contribute by causing venous hypertension. Prolonged venous hypertension causes tissue edema, inflammation, and hypoxia, leading to symptoms. Pressure may be transmitted to superficial veins if valves in perforator veins, which connect deep and superficial veins, are ineffective.

The most common risk factor for chronic venous insufficiency is

  • Deep venous thrombosis

Other risk factors include

  • Trauma

  • Older age

  • Obesity

  • Sitting or standing for long periods

  • Pregnancy

Idiopathic cases are often attributed to a history of occult DVT.

Post-thrombotic syndrome is symptomatic chronic venous insufficiency that follows DVT. Risk factors for post-thrombotic syndrome in patients with DVT include proximal thrombosis, recurrent ipsilateral DVT, and body mass index (BMI) 22 kg/m2. Age, female sex, and estrogen therapy are also associated with the syndrome.

Symptoms and Signs of Chronic Venous Insufficiency

Clinically evident chronic venous insufficiency may not cause any symptoms but always causes signs; post-thrombotic syndrome always causes symptoms. Both disorders are a concern because their symptoms can mimic those of acute DVT and both can lead to substantial reductions in physical activity and quality of life.

Symptoms include a sense of fullness, heaviness, aching, cramps, pain, tiredness, and paresthesias in the legs; these symptoms worsen with standing or walking and are relieved by rest and elevation. Pruritus may accompany skin changes. Signs occur along a continuum: no changes to varicose veins (rare) to edema to stasis dermatitis on the lower legs and at the ankles, with or without ulceration (see table Clinical Classification of Chronic Venous Insufficiency). The calf may be painful when compressed.

Table
Table

Venous stasis dermatitis consists of erythema, hyperpigmentation, induration, venous ectasia, lipodermatosclerosis (fibrosing subcutaneous panniculitis), lichenification, and venous stasis ulcers. Erythema may be difficult to appreciate in dark skin.

Stasis Dermatitis (Chronic Changes)
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Chronic stasis dermatitis may appear as fibrotic skin thickening and hyperpigmentation. The changes are characteristic in both light-skinned (top) and dark-skinned (bottom) people, here appearing more pronounced in the bottom photo.
Images provided by Thomas Habif, MD.

Venous stasis ulcers may develop spontaneously or after affected skin is scratched or injured. They typically occur around the medial malleolus, tend to be shallow and moist, and may be malodorous (especially when poorly cared for) or painful. They do not penetrate the deep fascia. In contrast, ulcers due to peripheral arterial disease eventually expose tendons or bone.

Venous Stasis Ulcer Manifestations
Early Venous Stasis Ulcer
Early Venous Stasis Ulcer

Venous stasis includes lichenification and hyperpigmentation. A shallow ulcer is developing superior to the medial malleolus.

... read more

© Springer Science+Business Media

Large Venous Stasis Ulcer
Large Venous Stasis Ulcer

This large venous stasis ulcer is surrounded by brawny induration.

© Springer Science+Business Media

Stasis Dermatitis (Ulcer)
Stasis Dermatitis (Ulcer)

Venous stasis ulcers develop as a result of inadequately treated stasis dermatitis; they may quickly follow the first signs of stasis dermatitis.

... read more

Image provided by Thomas Habif, MD.

Healed Venous Stasis Ulcer
Healed Venous Stasis Ulcer

Roberto A. Penne-Casanova/SCIENCE PHOTO LIBRARY

Leg edema tends to be unilateral or asymmetric; bilateral symmetric edema is more likely to result from a systemic disorder (eg, heart failure, hypoalbuminemia) or certain medications (eg, calcium channel blockers).

In general, unless the lower extremities are adequately cared for, patients with any manifestation of chronic venous insufficiency or post-thrombotic syndrome are at risk of progression to more advanced forms.

Diagnosis of Chronic Venous Insufficiency

  • Clinical evaluation

  • Ultrasonography to exclude DVT

Diagnosis is usually based on history and physical examination. A clinical scoring system that ranks 5 symptoms (pain, cramps, heaviness, pruritus, paresthesia) and 6 signs (edema, hyperpigmentation, induration, venous ectasia, blanching hyperemia, pain with calf compression) on a scale of 0 (absent or minimal) to 3 (severe) is increasingly recognized as a standard diagnostic tool of disease severity (1). Scores of 5 to 14 on 2 visits separated by 6 months indicate mild-to-moderate disease, and scores of 15 indicate severe disease.

Lower-extremity duplex ultrasonography reliably excludes or confirms DVT. Absence of edema and a reduced ankle-brachial index suggest peripheral arterial disease rather than chronic venous insufficiency and post-thrombotic syndrome.

Diagnosis reference

  1. 1. Kahn SR. Measurement properties of the Villalta scale to define and classify the severity of the post-thrombotic syndrome. J Thromb Haemost 2009;7(5):884-888. doi:10.1111/j.1538-7836.2009.03339.x

Treatment of Chronic Venous Insufficiency

  • Elevation

  • Compression using bandages, stockings, and/or pneumatic devices

  • Topical treatments

  • Treatment of secondary infection, when present

Some experts believe that weight loss, regular exercise, and reduction of dietary sodium may benefit patients with bilateral chronic venous insufficiency. However, all interventions may be difficult to implement.

Elevating the leg above the level of the right atrium decreases venous hypertension and edema, is appropriate for all patients, and should be done a minimum of 3 times a day for 30 minutes. However, most patients cannot reliably adhere to this schedule during the day.

Compression is recommended for treatment and prevention of the effects of chronic venous insufficiency (ie, edema, venous ulcers) and is indicated for all patients. Although the data are mixed as to whether compression stockings prevent post-thrombotic syndrome, they are useful to reduce symptoms of swelling, pain, and tightness that may occur after deep vein thrombosis (1).

Elastic bandages are used initially until edema and ulcers resolve and leg size stabilizes; commercial compression stockings are then used. Stockings that provide 20 to 30 mm Hg of distal circumferential pressure are indicated for smaller varicose veins and mild chronic venous insufficiency; 30 to 40 mm Hg is indicated for larger varicose veins and moderate to severe disease. Infrequently, higher compression pressures (eg, > 40 mm Hg) can be used but may not be tolerated for long-term use.

Stockings should be put on when patients awaken, before leg edema worsens with activity, and should exert maximal pressure at the ankles and gradually less pressure proximally. Adherence to this treatment varies; many patients consider stockings irritating, restricting, or cosmetically undesirable; many patients have difficulty putting them on.

Intermittent pneumatic compression (IPC) uses a pump to cyclically inflate and deflate hollow plastic leggings. IPC provides external compression, squeezing blood and fluid out of the lower legs. It effectively treats severe post-thrombotic syndrome and venous stasis ulcers but may be no more effective than compression stockings alone and is much less practical for patients to adhere to on an ongoing basis.

Topical wound care is important in venous stasis ulcer management

Medications have no role in routine treatment of chronic venous insufficiency, although many patients are given aspirin, topical corticosteroids, diuretics for edema, or antibiotics.

Surgery (eg, venous ligation, stripping, valve reconstruction) is also typically ineffective. Grafting autologous skin or skin created from epidermal keratinocytes or dermal fibroblasts may be an option for patients with stasis ulcers refractory to all other measures (2); however, there is a risk that the graft may reulcerate, especially if there is ongoing venous hypertension.

Treatment references

  1. 1. Kahn SR, Comerota AJ, Cushman M, et al. The postthrombotic syndrome: evidence-based prevention, diagnosis, and treatment strategies: a scientific statement from the American Heart Association [published correction appears in Circulation. 2015 Feb 24;131(8):e359]. Circulation 2014;130(18):1636-1661. doi:10.1161/CIR.0000000000000130

  2. 2. Jones JE, Nelson EA, Al-Hity A. Skin grafting for venous leg ulcers. Cochrane Database Syst Rev 2013;2013(1):CD001737. Published 2013 Jan 31. doi:10.1002/14651858.CD001737.pub4

Prevention of Chronic Venous Insufficiency

Primary prevention of chronic venous insufficiency involves adequate anticoagulation after DVT and use of compression stockings for up to 2 years after DVT or lower extremity venous trauma. However, a meta-analysis of randomized trials comparing compression stockings with placebo (ie, either none or sham-compression stockings) failed to show a significant reduction in post-thrombotic syndrome (1).

Lifestyle changes (eg, weight loss, regular exercise, reduction of dietary sodium) can decrease risk by decreasing lower extremity venous pressure.

Prevention reference

  1. 1. Subbiah R, Aggarwal V, Zhao H, Kolluri R, Chatterjee S, Bashir R. Effect of compression stockings on post thrombotic syndrome in patients with deep vein thrombosis: a meta-analysis of randomised controlled trials. Lancet Haematol 2016;3(6):e293-e300. doi:10.1016/S2352-3026(16)30017-5

Key Points

  • Skin changes range on a continuum from normal skin or mildly ectatic veins to severe stasis dermatitis and ulceration.

  • Symptoms are more common with post-thrombotic syndrome and include heaviness, aching, and paresthesias.

  • Diagnosis is based on inspection, but patients should have ultrasonography to rule out deep venous thrombosis.

  • Treatment is with elevation and compression; medications and surgery are typically ineffective.

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