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Clinical deterioration of patients with chronic venous disease (CVD) has been well described and a standardized classification has been proposed. The progressive hemodynamic deterioration producing these clinical findings is less well appreciated. This study examines and correlates venous hemodynamics with clinical severity in patients with CVD. Two hundred seventy-four extremities from 149 patients with varying degrees of CVD and 56 extremities from 28 symptom-free volunteers were evaluated clinically and hemodynamically. Each limb was assessed for functional venous volume, degree of valvular insufficiency, efficiency of the calf muscle pump, and noninvasive estimate of ambulatory venous pressure. In addition, exercise venous pressures were recorded in 56 extremities from 36 patients and 9 extremities from 6 volunteers. As CVD progresses from class 0 to class 2, venous volume expands, valvular function deteriorates, the calf muscle pump becomes inefficient, and ambulatory venous hypertension develops. However, once extremities develop brawny edema or hyperpigmentation, further deterioration of limb hemodynamics does not occur. Patients with deep venous obstruction have more severe valvular insufficiency, calf muscle pump dysfunction, and ambulatory venous hypertension than have patients without evidence of obstruction. Residual volume fraction offers a reliable noninvasive estimate of ambulatory venous pressure (r = 0.76), although its correlation was significantly better for patients without venous obstruction (r = 0.86) than for those with obstruction (r = 0.40; p < 0.05). Deterioration in venous hemodynamics parallels clinical severity through class 2. Once brawny edema and hyperpigmentation occur, ulceration develops without additional deterioration of venous hemodynamics.
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PMID:Hemodynamic deterioration in chronic venous disease. 143 61

Venous ulceration is the result of progressive chronic venous insufficiency, the pathophysiology of which is complex and incompletely understood. Ambulatory venous hypertension in this disease has been well-documented; however, relatively little attention has been directed toward other parameters of venous function. This study evaluates a spectrum of hemodynamic variables and the degree to which they are altered in patients with venous ulceration, and correlates ambulatory venous pressure (AVP) with the noninvasive estimate of this parameter. Air-plethysmography was used to evaluate 36 ulcerated extremities from 30 patients with chronic venous disease and 80 asymptomatic extremities from 54 patients. This technique measures the functional venous volume (VV), assesses valvular function [Venous Filling Index (VFI)], evaluates the efficiency of the calf muscle-pump [Ejection Fraction (EF)], and provides an estimation of ambulatory venous pressure [Residual Volume Fraction (RVF)]. In addition, AVP's were recorded in 13 asymptomatic extremities from 10 patients and 16 ulcerated extremities from 14 patients with chronic venous disease. Significant differences existed between the two groups for all of the hemodynamic parameters. Ulcerated extremities had greater venous volumes, displayed marked deterioration in valvular competence and calf muscle-pump function, and showed significant ambulatory venous hypertension compared to the asymptomatic group. Additionally, the relationship between RVF and AVP appeared linear, with a correlation coefficient of 0.87. Air-plethysmography currently provides the most complete evaluation of venous hemodynamics and should improve our understanding of the pathophysiology of chronic-venous disease.
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PMID:The hemodynamics of venous ulceration. 154 69

The value of the vascular examination cannot be over-estimated. Symptoms of vascular disease present in the foot and lower extremity may actually be manifestations of severe life-threatening disease. Symptoms, their location, and the frequency and quality of the patient's pain often provide valuable clues for the clinician's diagnosis. Central nervous system symptoms, ocular disturbances, cardiac symptoms, impotence, or constitutional disturbances may all indicate systemic arterial disease. Risk factors for this disease include smoking, hypertension, hyperlipidemia, genetic predisposition, diabetes, emotional stress, and physical inactivity. Those factors attributable to hypercoagulability and venous disease are birth control pill use, estrogen chemotherapy, obesity, prolonged immobilization, paralysis, previous thrombotic episodes, venous stasis disease, and varicose veins. An accurate bilateral assessment of blood pressure, pulses, and capillary perfusion is of critical importance. Careful inspection of the extremity for trophic changes, skin color, texture, temperature, edema, ulceration, atrophy, or paresis, will provide clues of vasculopathy. A relatively accurate assessment of circulatory status may be obtained without the use of exotic instruments. Simple tests such as the elevation and dependency tests, capillary bed return test, venous filling time test, along with blood pressure, pulse, and possibly oscillometry data are valuable in arterial evaluation. Such venous tests as inspection, percussion, Homan's sign, Trendelenburg, and Perthes' tourniquet are useful in the determination of the presence of venous disease. Fortunately, over the past few years tremendous advances have been made in the technology of the vascular laboratory. If symptoms are discovered during the vascular history and physical examination, the complete noninvasive study will provide impressive data to quantitate and specifically establish the diagnosis.
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PMID:The vascular history and physical examination. 173 54

Partial or complete obstruction of the superior vena cava and its major tributaries occassionally results in incapacitating venous hypertension of the upper extremities and/or head and neck. Factors intrinsic and extrinsic to the central veins play a role in the pathogenesis. The more common causes include mechanically and chemically induced intimal injury with resultant fibrosis, sclerosis, or thrombosis and neoplastic masses with external compression or direct extension in the central venous structures. Medical therapy is indicated in the acute situation and generally allows the time necessary for development of collateral drainage routes. Persistent or progressive symptomatic venous hypertension develops in 5% to 40% of these patients, and approximately 10% of the patients will remain incapacitated. Presented here is a series of 10 patients who underwent reconstruction of the superior vena cava or central veins for incapacitating venous hypertension of the upper extremities and/or head and neck. Reconstruction was accomplished by venous transposition (three patients), externally reinforced ePTFE (six patients), and reversed saphenous vein graft (one patient). No perioperative deaths occurred; however, two late deaths occurred at 3 and 9 months after reconstruction from causes unrelated to the operative procedure. One patient experienced early postoperative graft thrombosis requiring thrombectomy, after which the graft remained patent. All patients had patent grafts and were asymptomatic with respect to their venous disease at the time of preparation of this manuscript, with a mean follow-up period of 30 months. Specific details concerning these 10 cases are discussed and integrated with a focused review of the literature and the historic development of the intraoperative techniques and postoperative care that facilitate the successful management of patients with symptomatic central venous occlusion.
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PMID:Superior vena cava and central venous reconstruction. 186 92

Duplex ultrasound combines B-mode imaging and pulsed Doppler flow analysis and is rapidly becoming the most useful and widely applied method for the evaluation of atherosclerotic arterial disease. Recent technical improvements including color flow Doppler allow its application to practically all vascular beds in the body. Duplex is noninvasive and in many areas its accuracy in the detection of arterial stenosis and occlusion rivals angiography. Duplex ultrasound has become the preferred method of evaluation of patients with cerebrovascular disease. It provides information about the degree of stenosis, location of disease, and plaque characterization, and in many cases replaces standard cerebral arteriography. Duplex ultrasound has been used to detect renal artery stenosis in patients suspected of having renovascular hypertension with an accuracy of 93% in the diagnosis of hemodynamically significant stenosis. It also has important applications in the assessment of mesenteric artery stenosis, peripheral vascular disease, and venous disease. Because it is accurate, reasonably inexpensive, and noninvasive, duplex ultrasound can be used to follow the progression of untreated atherosclerotic lesions throughout the body. Used in this fashion, it provides important information about the natural history of atherosclerotic lesions, their clinical prognosis, and the effect of interventions, either medical or surgical, on lesions.
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PMID:Duplex ultrasound in the assessment of vascular disease in clinical hypertension. 187 8

Factors contributing to deep vein thrombosis (DVT) were studied in 51 patients (62 knees) who had a cementless total knee arthroplasty (TKA) and in 51 patients (69 knees) who had a cemented TKA. All patients were treated with a primary TKA using a porous-coated anatomic prosthesis with a porous-coated central tibial stem. Deep vein thrombosis was diagnosed by roentgenographic venography, and pulmonary embolism was diagnosed by perfusion lung scanning. Incidence of DVT was 32%, and there was no pulmonary embolism. The factors that do not seem to have much relevancy to DVT were advanced age, orthopedic disease, one- or two-staged bilateral TKA, venous anatomic variations, number of venous valves, coagulation assay data, hypertension, tourniquet time, choice of cementless or cemented TKA, severity or duration of operation, amount of blood loss, and amount of blood transfused. Conversely, more immediate relevant factors were obesity, postoperative prolonged immobilization, earlier venous disease, and hyperlipidemia.
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PMID:Factors leading to low incidence of deep vein thrombosis after cementless and cemented total knee arthroplasty. 195 58

The purpose of this study was to examine the effects on the skin microcirculation of a short period of venous hypertension. 34 subjects (17 patients with lipodermatosclerosis and 17 controls) were studied. Laser-Doppler flowmetry was used to assess the hyperaemic responsiveness of the skin following three minutes of ischaemia. This was done by measuring the ratio of peak to basal flow, and the time taken to reach 95% of peak flow. The limb was then subjected to 30 minutes of venous hypertension, following which the hyperaemic responses were repeated. Normal controls demonstrated a significant reduction in hyperaemic response after venous hypertension. Liposclerotic skin had a much less pronounced response to ischaemia which was not significantly affected by 30 minutes of venous hypertension. The clinically normal skin in venous patients showed intermediate values. The results suggest that a short period of venous hypertension causes an immediate deficit in microcirculatory function. This short time scale is consistent with the white cell activation theory of skin damage in venous disease. The loss of vasodilatory capacity by liposclerotic skin may reflect either the constricting effect of pericapillary fibrin cuffs or a fixed degree of capillary occlusion.
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PMID:Skin microcirculatory responses in chronic venous insufficiency: the effect of short-term venous hypertension. 203 3

Lipodermatosclerosis of the lower extremity, with or without ulceration, is a common manifestation of severe venous disease and the result of sustained venous hypertension. The latter is generally a sequela of deep vein thrombosis. Factors that enhance clot formation or impair fibrinolysis contribute to the pathogenesis of venous disease. It is already established that faulty fibrinolysis may play a pathogenic role in patients with venous disease. We examined the possibility that patients with venous disease have abnormally low plasma levels of proteins C and S, two proteins whose deficiencies have been reported to cause an increased frequency of thromboembolic disease. Using immunologic and functional assays for plasma proteins C and S, we found that 4 (21%) of 19 patients with lipodermatosclerosis and leg ulcers had abnormally low levels of protein C or protein S. One of 7 patients with lipodermatosclerosis without ulceration had a profoundly depressed level of protein C and a history of cerebral stroke at a young age. Plasma levels of protein C were normal in five patients with arterial insufficiency severe enough to cause leg ulceration. We conclude that abnormally low plasma levels of proteins C and S may be found in patients with lipodermatosclerosis and venous ulceration. As with the abnormally low fibrinolytic activity in these patients, our findings indicate a possible propensity for increased thrombotic disease.
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PMID:Protein C and protein S plasma levels in patients with lipodermatosclerosis and venous ulceration. 203 43

It has been demonstrated that skin blood flow of postphlebitic limbs is increased. Also the venoarteriolar response (VAR), i.e. precapillary vasoconstriction present in normal limbs on standing up, is reduced in limbs with venous insufficiency, resulting in capillary hypertension. The supine skin resting flow (SF) and the skin flow on standing (SF) have been measured with laser-Doppler in 30 normal lower limbs and 70 postphlebitic limbs with ambulatory venous pressure greater than 65 mmHg; also, the rate of ankle swelling (RAS) has been measured with strain-gauge plethysmography. The VAR was derived from VAR = 100* (RF-SF)/RF. The reduction of VAR and the increase in SF, which has been demonstrated in the postphlebitic limbs, correlated well with the rate of ankle swelling (RAS). The measurements of SF, VAR and RAS evaluate objectively the degree of impairment of the microcirculation because of severe venous disease. They offer the possibility to study the natural history and the effect of treatment of venous hypertensive microangiopathy.
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PMID:Skin flow and swelling in post-phlebitic limbs. 266 73

Graded high-compression support hosiery have long been recognized as a physiologically significant mode of therapy for chronic venous disease because of their effects on the hemodynamics of venous return. Photoplethysmography (PPG) in the noninvasive vascular laboratory is now recognized as a quick, simple, and noninvasive measurement technique, which correlates well with ambulatory venous pressure in the postphlebitic limb with chronic venous insufficiency. The purpose of this study was to evaluate the hemodynamic effects, as measured by PPG, of 40 mm Hg graded compression support hosiery in the treatment of patients with a documented history of hospital-treated thrombophlebitis. Fifty lower extremities among 38 patients with a documented history of deep vein thrombosis and chronic venous insufficiency were matched against 50 control extremities among patients without disease. All 50 lower extremities in the study group had abnormal noninvasive venous studies, including Doppler ultrasound examination, phleborheography, and PPG (mean, 5.9. seconds). Thus these patients were ascertained to have incompetent deep venous systems, but with normal arterial flow as documented by ankle:brachial ratios. After application of 40 mm Hg gradient compression stockings to the study group, PPG measurements in all 50 limbs initially converted to normal (20.6 seconds). Abnormal PPG measurements were converted to normal in postphlebitic limbs with the application of graded compression stockings in the 29 patients who wore the prescribed hosiery; 21 patients did not wear the gradient stockings after the initial evaluation(s) and were not found to have improved PPG measurements. It can be concluded that such gradient stockings should be associated with a reduction in ambulatory venous pressure, which may, in turn, lead to clinical prevention or improvement of the various sequelae associated with chronic venous hypertension.
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PMID:Hemodynamic assessment of high-compression hosiery in chronic venous disease. 331 77


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