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 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Uniform view of chronic venous diseases has been formed in the last 3 decades. Chronic venous insufficiency (CVI) is a functional disorder of the venous system of the lower limb. The basis of the pathology is always the venous hypertension caused by valvular insufficiency and reflux with or without venous outflow obstruction. Epifascial, subfascial and transfascial forms of CVI can be distinguished. In the practice these forms are almost always combined. The consistent venous hypertension is the initiating factor in alterations in the microcirculation which leads to skin changes and venous ulceration. The precise mechanism of the development of venous leg ulcer is still uncertain. A recent hypothesis suggests that leukocytes are trapped in the capillaries and attaching to the endothel they become activated and release proteolytic enzymes, free radicals which have destructive effects on lipid membranes, proteins as well as on many connective tissue compounds. The endothelium plays active role in the complex mechanism. Increased expression of tissue metalloproteinases has been observed in the periulcer skin. The presence of perivascular leukocyte infiltration and fibrin cuff is a reflexion of an inflammatory process. The clinical stages of CVI are likely to be the results of a systemic inflammatory response to a period of venous hypertension.
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PMID:Pathomechanism of chronic venous insufficiency and leg ulcer. 1548 13

Peripheral edema develop as a consequence of imbalance in the processes of filtration, resorption and lymphatic transport in the capillary bed. Venous hypertension and impaired lymphatic function belong to the most important underlying pathomechanisms. Chronic venous insufficiency as a result of valve degeneration as well as venous obstruction in acute deep thrombosis lead to venous hypertension and to an increase of filtration pressure. As venous diseases are frequent, they are one of the most reasons for a swollen leg in clinical everyday life. Primary and secondary disturbances of the lymphatic system are another important reason for interstitial liquid retention. Although there are about 140 millions of people suffering from lymphedema worldwide, the disease is still underdiagnosed.
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PMID:[Venous and lymphatic reasons for edema--the swollen leg from the angiologist's point of view]. 1560 55

Chronic venous insufficiency (CVI) is a pathologic condition caused by valvular incompetence, with or without associated venous outflow obstruction, which may affect both the superficial and the deep venous system, causing venous hypertension and stasis. The most common form of CVI is primary varicose veins due to the insufficiency of the saphenous system. Color-Doppler sonography (CDS) is actually the main diagnostic technique of imaging for CVI. In this article, we describe the anatomy, the technique, and the information necessary to the radiologist to perform CDS in chronic venous insufficiency. The knowledge of the venous anatomy is the cornerstone for an adequate sonographic examination. The venous network in the lower extremities is divided into three systems: superficial, deep, and perforating veins. Deep veins are "comitantes" to the corresponding arteries and run under the muscular fascia. Superficial veins course into the subcutaneous fat, superficially to the deep muscular fascia; the main superficial veins are the greater and lesser saphenous and their tributaries. Connection between the saphenous veins are defined as communicating veins. Superficial and deep veins are connected by perforating veins, with flow directed, under normal circumstances, from the superficial to the deep system. The main perforating are the Hunter in the mid thigh, the Dodd in the lower thigh, the Boyd in the upper calf, and the Cockett's in the middle and lower calf. Sonographic examination must be performed in the upright and supine position. Compression sonography and color and PW Doppler are systematically employed to assess the absence of deep venous thrombosis. Femoro-popliteal veins are evaluated with color and PW Doppler for valvular insufficiency with reflux by performing Valsalva maneuver and calf compression. The sapheno-femoral and sapheno-popliteal junctions are examined to identify type of junction, continence, accessory saphenous, and incompetent collaterals. Perforating veins are usually identified at the medial aspect of the thigh and at the medial, lateral, and posterior aspects of the leg. Outward flow (lasting more than 500 ms) in the perforating veins should be considered a sign of their incompetence. Several surgical and interventional procedures are now available for the treatment of the CVI, as follows: vein ligation and stripping, stab avulsion, endoluminal occlusion of the saphenous trunks, subfascial endoscopic perforator surgery, and valvuloplasty.
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PMID:Color-Doppler sonography in chronic venous insufficiency: what the radiologist should know. 1575 79

This paper deals with essentials of trophic venous ulcer pathogenesis, their criticism as well as with the treatment of some phenomena which should be taken into account when creating any new theory of the pathogenesis and essentials of the treatment of trophic ulcers. Basically, this concerns inflammation as a general biological reaction. Chronic venous insufficiency (CVI) changes capillary permeability. The paravasal space is invaded by red blood cells. On break down they secrete hemosiderin, protein molecules and lipid complexes. All this is denatured to form substances liable to resorption. According to the biological laws resorption may be brought about only by means of inflammatory reaction, more exactly, through its cellular phases--acute (leucocytic) and chronic (macrophagal). It is assumed that the main signal for activation of leucocytes is accumulation of the above-indicated decomposition products rather than hypertension which, in non-occlusive CVI forms, cannot be proven numerically. The basic cause of trophic ulcers lies in the permanent cellular phase of the common defence inflammatory reaction because of the presence of the non-transient injurious factor. The permanently repeated cycles of the inflammatory trio (vascular, cellular and reparative phases), being in different correlation, form in the ulcer itself an unusual system which is not governed by the regularities of wound process. Bacterial contamination and colonization of trophic ulcer occur without fail but this process bears secondary character after impairment of barrier skin function and emergence of skin defects. At the same time different processes may take place in trophic ulcer such as exudation in the form of serous and seropurulent discharge, formation of the fibrinonecrotic deposit, formation of granulation tissue, and appearance of islets of unstable epithelialization. From the conceptual viewpoint such a state can be regarded as a system marked by closed pseudochaotic activity. To start up healing, this self-reproducing system must be destroyed while ulcer must transform to a wound with the linear sequence of processes.
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PMID:[Some aspects of the pathogenesis of trophic venous ulcers]. 1603 24

Chronic venous insufficiency (CVI) with the resultant clinical sequelae significantly reduces quality of life. Most elderly patients with CVI are treated nonoperatively owing to concerns of increased operative risk and therefore suffer more advanced disease. Radiofrequency ablation (RFA) has emerged as a minimally invasive procedure to treat patients with superficial venous insufficiency (SVI) due to great saphenous vein (GSV) incompetence. The purpose of this study was to review our experience using RFA of the GSV to treat CVI due to superficial disease in elderly patients compared to younger patients in terms of procedure-related morbidity and severity of disease at time of treatment. RFA treatment of the GSV was performed in 490 extremities of 421 patients with SVI between March 2001 and December 2002. Indications, medical history, and outcome (operative complications and hospital stay) were compared between 2 groups: Group I:41 extremities of 35 patients, 70 years if age or older (mean 75 +/-4); and Group II:449 limbs of 386 patients younger than 70 years (mean 47 +/-11). The incidence of skin pigmentation and healed/nonhealed ulcers (CEAP 4-6) was significantly higher in the elderly than in the younger group (41% vs 16%, p <0.05). Hypertension, diabetes, and previous myocardial infarction were 2.8, 5.4, and 6.7 times more prevalent in the elderly (p <0.05), respectively. There were no major postoperative complications in either group; 97% of all patients were discharged on the day of operation and there was no difference between the 2 groups in overnight hospital stay. There is a treatment bias against operative management in elderly patients with SVI, as evidenced by their more advanced disease at the time of definitive treatment than their younger cohort. However, operative morbidity is no different compared to the younger subset. RFA is a safe and effective procedure for older patients; therefore, the threshold for operative management of older patients should be lowered.
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PMID:Chronic venous insufficiency due to great saphenous vein incompetence treated with radiofrequency ablation: an effective and safe procedure in the elderly. 1607 43

Chronic venous insufficiency is linked to venous hypertension and forces of shear stress on the endothelium. Venous hypertension depends upon two forces: the weight of a column of blood from the right atrium transmitted through the valveless vena cava and iliac veins to the femoral vein, and pressure generated by contracting skeletal muscles of the leg transmitted through failed perforating veins. When valve failure occurs in superficial axial veins and perforating veins, the venous pressure in the veins and venules of the skin and subcutaneous tissue is raised. The skin changes in chronic venous insufficiency are directly related to the severity of the venous hypertension. Also, pathologic changes in the valves are linked to venous hypertension and leukocyte infiltration and activation. It is hypothesized that acute venous pressure elevations cause a shift in the venous hemodynamics with changes in wall shear stress. This initiates the inflammatory cascade. Daflon 500 mg ameliorates the effects of chronic inflammation. In randomized trials, 60 days of therapy with Daflon at a dosage of 500 mg 2 tablets daily was effective, in addition to elastic compression, in accelerating venous ulcer healing. Because venous insufficiency is linked to venous hypertension and an inflammatory reaction, it appears that Daflon 500 mg 2 tablets daily shows a great potential for accomplishing blockade of the inflammatory cascade.
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PMID:Chronic venous insufficiency and the therapeutic effects of Daflon 500 mg. 1619 22

Chronic venous insufficiency (CVI) causes a well-defined microangiopathy described as venous hypertensive microangiopathy (VHM) leading to venous ulcerations. VHM is mainly observed in the distal part of the leg, in the perimalleolar region. In VHM edema is the consequence of increased capillary pressure and reduced local clearance, and this affects local perfusion. The healing of venous ulcers is usually very slow. Many treatments are available, but there is still no standard. Oral Pycnogenol is effective in venous disease and particularly in controlling edema. The aim of this study was the evaluation of the local effects of Pycnogenol on ulcers healing associated with venous hypertension. The study lasted 6 weeks including 18 patients (16 completed the study) with venous ulcerations. The oral treatment with Pycnogenol was compared with a combination treatment including oral and local treatment. In subjects treated with the combination treatment (oral and local), venous ulcers healed better (there was a faster reduction in ulcerated area) in comparison with oral treatment only. According to this pilot study Pycnogenol appears to have an important role in local treatment of venous ulcers improving healing and signs/symptoms.
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PMID:Venous ulcers: microcirculatory improvement and faster healing with local use of Pycnogenol. 1632 46

Chronic venous insufficiency (CVI) results from venous hypertension secondary to superficial or deep venous valvular reflux. Treatment modalities are aimed at reducing venous valvular reflux, thereby inhibiting the ensuing pathologic inflammatory process. Compression therapy using pumps, bandaging, and/or graded compression stockings is the mainstay of treatment for CVI. Compression therapy has been shown to be effective in reducing venous hypertension retarding the development of inflammation and pathologic skin changes. Pharmacologic agents such as diuretics and topical steroid creams reduce swelling and pain short term but offer no long-term treatment advantage. Herbal supplements may reduce the inflammatory response to venous hypertension, but are not licensed by the US Food and Drug Administration, and vary in their efficacy, quality, and safety. However, several randomized controlled trials using the herbal horse chestnut seed extract containing aescin have shown short-term improvement in signs and symptoms of CVI. Endovascular and surgical techniques aimed at treatment of primary and secondary venous valvular reflux have been shown to improve venous hemodynamics promoting healing of venous ulcers and improving quality of life. The newer endovascular treatments of varicose veins using laser, radiofrequency ablation, and chemical foam sclerotherapy show some promise.
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PMID:Treatment of chronic venous insufficiency. 1748 14

Chronic venous insufficiency (CVI) is a severe disease affecting the venous system of the lower limbs. Compression therapy aims to counteract the venous hypertension caused by CVI. However, in spite of significant advances in compression treatments in recent years, CVI and its associated diseases are frequently characterized by slow healing rates and a need for more aggressive therapies such as surgery. Surface neuromuscular electrical stimulation (SNMES) offers potential benefits when used in conjunction with compression therapy by increasing venous return through muscular compression of the calf muscles. In order to assess the long term feasibility of SNMES with compression hosiery as a treatment modality for CVI, it is necessary to evaluate the effects of such a treatment on subject blood flow and comfort levels. This paper presents the results of a study investigating the effects of long term SNMES and compression hosiery applied to the lower limb, in the comfort and blood flow of healthy subjects.
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PMID:The effect of surface neuromuscular electrical stimulation and compression hosiery applied to the lower limb, on the comfort and blood flow of healthy subjects. 1916 52

Chronic venous insufficiency is a complex disease that can result in severe sequelae including venous ulceration. Though the exact progression from chronic venous insufficiency to venous ulcer remains unclear, the high cost and burden of this disease on patients and society is quite clear. Sustained ambulatory venous pressures or venous hypertension plays an integral role in the development of venous ulceration and involves the failure of the calf muscle pump system. Standard of care involves compression therapy to assist the calf muscle pump. However, several cofactors may contribute to or exacerbate this disease and understanding their impact may provide insight into new treatment modalities. Nerve involvement, which may result in neuropathic pain and muscle dysfunction, alterations in mobility and a decrease in range of motion may lead to gait alterations all affecting calf muscle pump function. In this paper, we analyze these cofactors and discuss possible treatment options to target them. Physicians treating this disease should be aware of the numerous factors involved in its development. Exploring new treatment options may 1 day lessen the burden and suffering caused by venous insufficiency.
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PMID:Venous ulcers: A reappraisal analyzing the effects of neuropathy, muscle involvement, and range of motion upon gait and calf muscle function. 1932 Aug 81


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