Mechanisms of Lower Extremity Vein Dysfunction in Chronic Venous Disease and Implications in Management of Varicose Veins

The Effect of Standardized Doses of Hesperidin and Diosmin on Venous Wall Remodeling in Patients with Primary Varicose Veins: a Prospective Controlled Study “STANDARD”

Objective. To study the effect of fixed doses combination of hesperidin and diosmin on venous wall remodeling in patients with primary varicose veins after therapy and endovenous laser ablation (EVLA). Material and methods. A single-center parallel-group prospective controlled study (ClinicalTrials.gov ID: NCT06367166) included 83 patients with varicose veins C2—C3 and 20 healthy volunteers (83 women and 20 men). Subjects were divided depending on treatment strategy: group A — 20 patients received hesperidin (100 mg) and diosmin (900 mg) once a day for 6 months; group B — 20 patients without therapy and invasive treatment; group C — 21 patients received hesperidin (100 mg) and diosmin (900 mg) once a day for 6 months after EVLA; group D — 22 patients underwent EVLA; group E — 20 healthy volunteers. Compression stockings class 2 were prescribed in groups A, B, C and D. We assessed vascular wall remodeling markers using ELISA: von Willebrand factor (vWF), PECAM-1 (CD31), fibronectin (FN), vimentin (VIM), plasminogen activation inhibitor type 1 (PAI-1). Additionally, we studied severity of symptoms using VAS and VCSS scales, as well as quality of life using CIVIQ-20 questionnaire. Results. After 6-month therapy with fixed doses combination of bioflavonoids: hesperidin 100 mg and diosmin 900 mg (VENARUS), we observed more than 6-fold decrease in PAI-1 (p<0.001), more than 22-fold decrease in FN (p<0.001), 2-fold decrease in VIM (p=0.042), 3-fold decrease in vWF (p=0.001) and 1.5-fold decrease in PECAM-1 (p<0.001). EVLA combined with fixed doses combination of bioflavonoids was characterized by more than 9.5-fold decrease in serum PAI-1 (p<0.001), 4.5-fold decrease in FN (p<0.001), 2.5-fold decrease in VIM (p<0.001), 1.8-fold decrease in vWF (p=0.008) and 25% decrease in PECAM-1 (p<0.001) after 6-month therapy. Similar changes were not observed in other groups. The best results regarding severity of symptoms and quality of life were observed after EVLA including postoperative therapy with fixed doses combinations of bioflavonoids. Conclusion. Fixed doses combination of bioflavonoids (hesperidin 100 mg and diosmin 900 mg) contribute to significant changes of venous wall remodeling markers, relief of symptoms and QoL improvement in patients with varicose veins.

The Roles of Oxidative Stress and Red Blood Cells in the Pathology of the Varicose Vein

This review discusses sources of reactive oxygen species, enzymatic antioxidant systems, and low molecular weight antioxidants. We present the pathology of varicose veins (VVs), including factors such as hypoxia, inflammation, dysfunctional endothelial cells, risk factors in varicose veins, the role of RBCs in venous thrombus formation, the influence of reactive oxygen species (ROS) and RBCs on VV pathology, and the role of hemoglobin in the damage of particles and macromolecules in VVs. This review discusses the production of ROS, enzymatic and nonenzymatic antioxidants, the pathogenesis of varicose veins as a pathology based on hypoxia, inflammation, and oxidative stress, as well as the participation of red blood cells in the pathology of varicose veins.

Glycocalyx disruption, endothelial dysfunction and vascular remodeling as underlying mechanisms and treatment targets of chronic venous disease

The glycocalyx is an essential structural and functional component of endothelial cells. Extensive hemodynamic changes cause endothelial glycocalyx disruption and vascular dysfunction, leading to multiple arterial and venous disorders. Chronic venous disease (CVD) is a common disorder of the lower extremities with major health and socio-economic implications, but complex pathophysiology. Genetic aberrations accentuated by environmental factors, behavioral tendencies, and hormonal disturbances promote venous reflux, valve incompetence, and venous blood stasis. Increased venous hydrostatic pressure and changes in shear-stress cause glycocalyx injury, endothelial dysfunction, secretion of adhesion molecules, leukocyte recruitment/activation, and release of cytokines, chemokines, and hypoxia-inducible factor, causing smooth muscle cell switch from contractile to synthetic proliferative phenotype, imbalance in matrix metalloproteinases (MMPs), degradation of collagen and elastin, and venous tissue remodeling, leading to venous dilation and varicose veins. In the advanced stages of CVD, leukocyte infiltration of the vein wall causes progressive inflammation, fibrosis, disruption of junctional proteins, accumulation of tissue metabolites and reactive oxygen and nitrogen species, and iron deposition, leading to skin changes and venous leg ulcer (VLU). CVD management includes compression stockings, venotonics, and surgical intervention. In addition to its antithrombotic and fibrinolytic properties, literature suggests sulodexide benefits in reducing inflammation, promoting VLU healing, improving endothelial function, exhibiting venotonic properties, and inhibiting MMP-9. Understanding the role of glycocalyx, endothelial dysfunction, and vascular remodeling should help delineate the underlying mechanisms and develop improved biomarkers and targeted therapy for CVD and VLU.

Personalized compression therapeutic textiles: digital design, development, and biomechanical evaluation

Physical-based external compression medical modalities could provide sustainable interfacial pressure dosages for daily healthcare prophylaxis and clinic treatment of chronic venous disease (CVD). However, conventional ready-made compression therapeutic textiles (CTs) with improper morphologies and ill-fitting of pressure exertions frequently limit patient compliance in practical application. Therefore, the present study fabricated the personalized CTs for various subjects through the proposed comprehensive manufacturing system. The individual geometric dimensions and morphologic profiles of lower extremities were characterized according to three-dimensional (3D) body scanning and reverse engineering technologies. Through body anthropometric analysis and pressure optimization, the knitting yarn and machinery variables were determined as the digital design strategies for 3D seamless fabrication of CTs. Next, to visually simulate the generated pressure mappings of developed CTs, the subject-specific 3D finite element (FE) CT-leg modelings with high accuracy and acceptability (pressure prediction error ratio: 11.00% ± 7.78%) were established based on the constructed lower limb models and determined tissue stiffness. Moreover, through the actual in vivo trials, the prepared customized CTs efficiently (Sig. <0.05; ρ = 0.97) distributed the expected pressure requirements referring to the prescribed compression magnitudes (pressure error ratio: 10.08% ± 7.75%). Furthermore, the movement abilities and comfortable perceptions were evaluated subjectively for the ergonomic wearing comfort (EWC) assessments. Thus, this study promotes the precise pressure management and clinical efficacy for targeted users and leads an operable development approach for related medical biomaterials in compression therapy.

Relationship between internal diameter and vasoconstriction in human varicose veins

Varicose veins are common lower extremity venous disorders characterized by dilated veins and incompetent valves. Although maintaining the required vein wall tone for adaptive responses depends on a proper contractile function of the human saphenous smooth muscle, the contractile properties of varicose veins are mostly unknown. We investigated the relationship between contractile responses and the internal diameter of human saphenous varicose veins. The absolute contractile forces induced by potassium chloride (KCl, 60 mmol/l), serotonin (5-hydroxytryptamine [5-HT], 10 µmol/l), and noradrenaline (NAd, 10 µmol/l) were similar between normal saphenous veins (control) and varicose veins. When the contractile forces were normalized to the internal diameter in each preparation, the contractile responses to these stimuli were significantly lower in varicose veins than in the control veins. Furthermore, varicose veins were divided into three groups according to their internal diameter (group 1, 3-4.5 mm; group 2, 4.5-6 mm; group 3, >6 mm). The contractile responses induced by KCl, 5-HT, and NAd did not differ between groups 1 and 2 and the control group, while the contractile responses in group 3 were significantly lower than those in the control group. Moreover, the contractions induced by KCl and NAd in Group 3 were smaller than those in group 1 or group 2. This trend was also observed in 5-HT-induced contractions, although the results were not statistically significant. In conclusion, contractile responses in varicose veins may be altered by an increase in internal diameter, although adequate contractile responses are preserved in some diameters.

Interleukin-13: association with inflammation and cysteine proteolysis in varicose transformation of the vascular wall

The present review considers current data on the structure, functions and role of interleukin-13 in the pathogenesis of vascular wall varicose transformation in terms of proteolysis and inflammatory response. It is known that interleukin-13 is able to interact with transforming growth factor-1 in diseases associated with fibrosis. The latter activates fibroblasts and excessive formation of the extracellular matrix, thereby inducing fibrosis of the vascular wall, which is one of the links in the pathogenesis of varicose veins. Also, to date, there is evidence of the interleukin-13 participation in the induction of certain proteolytic enzymes synthesis, such as matrix metalloproteinases. For the latter, participation in the transformation of the venous wall has been proven to date. The remodeling of the venous wall itself can lead to an increase in the expression of proteinases, providing a proteolytic mechanism for changing the structural organization of the venous wall in varicose veins of the lower extremities. At the same time, the involvement of lysosomal cysteine proteinases remains poorly understood. The expression and production of individual cathepsins are regulated by biologically active molecules: interleukin-1, interleukin-6, tumor necrosis factor , which are directly involved in inflammatory reactions in the wall of varicose veins. In particular, venous pathology develops in a vicious circle of inflammation with the formation of abnormal venous blood flow, chronic venous hypertension and dilation, and the recruitment of leukocytes. This leads to a further, deeper, remodeling of the walls and valves of the veins, an increase in blood pressure and the release of pro-inflammatory mediators chemokines and cytokines. In connection with the above, in order to understand the mechanisms of proteolysis in the vascular wall in varicose veins of the lower extremities, it is important to have an idea about the possible interactions of interleukin-13 with transforming growth factor-1, inflammatory cytokines, and cathepsins.

Effect of umbilical cord mesenchymal stem cells on hypoxia-inducible factor-1 alpha (HIF-1α) production in arteriovenous fistula (AVF) animal model: A preliminary study

Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor that plays a crucial role in cellular responses to hypoxia, such as in the development of intimal hyperplasia, a common complication in arteriovenous fistula (AVF) creation. While the application of umbilical cord mesenchymal stem cells (UC-MSCs) has shown promise in various regenerative medicine applications, including tissue repair and angiogenesis, the effect of UC-MSCs on HIF-1α level in the AVF has not been tested. Therefore, the aim of this study was to evaluate the effect of UC-MSCs administration on HIF-1α levels in the AVF animal model. An experimental study was conducted on 28 local male rabbits (Lepus domestica) using a post-test-only design. The rabbits were divided randomly into four groups: normal rabbit group (negative control), placebo-treated AVF rabbit group (positive control), AVF rabbits treated with in-situ UC-MSCs injection (one dose, 106 UC-MSCs/kg body weight), and AVF rabbits treated with intravenous UC-MSCs (one dose, 106 UC-MSCs/kg body weight (BW). HIF-1α level was measured using ELISA method after 28 days post-treatment. All data were analyzed using the one-way analysis of variance (ANOVA) and continued with the Duncan's post-hoc test. The data indicated that the levels of HIF-1α were different among all four groups (p<0.001). The post-hoc analysis revealed that the HIF-1α levels in both UC-MSC treated groups were significantly lower compared to untreated AVF rabbits (p<0.05). This study suggests that UC-MSCs could be a promising therapy to prevent and reduce intimal hyperplasia in AVF.

May thermal imaging be useful in early diagnosis of lower extremities chronic venous disease?

Introduction: World statistics confirmed that about 40-50% of men and 50-55% of women suffer from chronic venous disease. Currently, the Duplex ultrasound is the leading diagnostic method for chronic venous disease (CVD), but it has some limitations. Therefore, it is important to find a new diagnostic technique that will provide additional parameters, describing not only structural but also early metabolic and functional changes.

Materials and Methods: This study aimed to demonstrate the usefulness of the thermal imaging technique in the diagnosis of chronic venous disease. Results were obtained for two groups: 61 patients suffering from the primary chronic venous disease (CVD group) and 30 healthy people (control group). The obtained results compared the thermal imaging parameters to data obtained from the ultrasound examination. Parameters such as the reflux duration and extent of the CEAP classification were correlated with the mean temperature of the limb, the mean temperature of the lesion (determined using two methods), and the thermal range. Based on data obtained during the study, correlation coefficients were calculated for individual parameters.

Results: The results obtained show that the mean limb temperature, and especially the mean temperature of a proposed isothermal area, is significantly correlated with the range of reflux. The conducted tests showed the correlation between some thermal and ultrasonic parameters determined by Spearman's coefficient is 0.4 (p < 0.05).

Conclusions: Thus, parameters such as the isothermal area and the thermal range may be used as a preliminary quantitative diagnosis, similarly to those derived from the Duplex ultrasound.

INFLUENCE OF THE AMOUNT OF COMPRESSION ON VENOUS AND ARTERIAL BLOOD FLOW VELOCITY AND SKIN MICROCIRCULATION OF THE LOWER EXTREMITY

OBJECTIVE

The aim: To determine the effect of compression on the venous and arterial velocity of the main blood flow of the lower limb and the skin microcirculation of the rear part of the foot.

PATIENTS AND METHODS

Materials and methods: 20 healthy subjects participated in this study: 11 men 11 (55%) men and 9 (45%) girls. The ankle brachial index (ABI), femoropop¬liteal index, femoral arterial blood flow velocity (AFV), venous blood flow velocity (VFV), transcutaneous oxygen pressure (tcPO2) and carbon dioxide pressure (tcPCO2) were measured. After the general measurements were taken, the tire was inflated to 10 mm Hg under general basic conditions and kept for three minutes. The experiment ended when no decrease in tcPO2 was observed between two consecutive pressure levels.

RESULTS

Results: The average tire pressure to reach physiological zero was 80 mm Hg. for all participants. At 10 mmHg significant changes in indicators were found by 19% (p=0.0001). tcPCO2 values increased significantly at 10 mmHg (p=0.0319) and continued to increase until the end of the study. It was established that its values increased by 14% compared to the input data (p=0.0005).

CONCLUSION

Conclusions: At the maximum compression of 60 mmHg the arterial blood flow rate decreased by 5.5 times (p=0.0001). TcPCO2 increases significantly when compressed by 10 mm Hg also in parallel with the decrease in the regional perfusion index, which begins at an external compression of 40 mm Hg, which is evidence of the deterioration of the perfusion of the skin of the anterior part of the foot in healthy subjects.

Impact of compression on velocity of venous and arterial main blood flow and cutaneous microcirculation of the lower extremity

Objective. To study the impact of compression on velocity of venous and arterial main blood flow of the lower extremity, as well as cutaneous microcirculation in the back part of the foot in healthy individuals and patients with decompensated forms of varicose disease and postthrombophlebitis syndrome. Materials and methods. In the investigation 56 individuals took part and divided into three groups: Group I – 20 healthy persons; Group II – 15 patients with varicose disease in decompensated stage; Group III– 21 patients with decompensated stage of postthrombophlebitis syndrome. In all participants of the investigation the index of ankle–brachial pressure, deep–femoro–popliteal index, the regional perfusion index, transcutaneous partial pressure of oxygen and partial pressure of carbon dioxide, the arterial blood flow velocity in femoral artery and of venous blood flow distally from sapheno–femoral junction were measured before and after application of elastic medical knitwear of various Class of compression or the cuff pressure. Results. In the Class III compression in patients of Group III the transcutaneously registered indices crossing have occurred between partial pressure of oxygen and carbon dioxide, accompanied by domination of the carbon dioxide partial pressure over the oxygen partial pressure while further enhancement of the compression Class. In patients of Group II this tendency was observed while application of Class IV compression only. At the investigation beginning the values of partial pressure of carbon dioxide registered were higher in the Group III patients, than in the patients of Group II (p=0.0001). Conclusion. While application of the Class III compression the velocity of the hip venous blood flow, comparing with its initial values, have lowered at average by 78% in patients of Group II and at average in 7.4 times in the patients of |Group III (p=0.0001). It is affordable in patients, suffering decompensated postthrombophlebitic syndrome, to apply the elastic compression of Classes I–II, while in those, having varicose disease in decompensated stage, – the elastic compression of Classes III and iV as well.

Monocyte chemoattractant protein 1 plasma concentration in blood from varicose veins decreases under venoactive drug treatment

BACKGROUND

Vein-specific inflammation leads to vascular smooth muscle cells proliferation and extracellular matrix degradation of vein wall. This process is known as remodeling and is promoted by "trapped" leukocytes. Monocyte chemoattractant protein 1 (MCP-1) is a chemokine responsible for trafficking of leukocytes from blood to vein wall. The aim of this study was to measure the MCP-1 concentration in varicose veins blood before and after venoactive drug therapy and to compare it with a concentration of blood from varicose veins of subjects who did not receive drug treatment.

METHODS

Non-randomized comparative study was conducted on 30 patients with primary varicose veins. 20 patients of the study group received diosmin 900 mg/hesperidin 100 mg once daily. 10 controls received no treatment. MCP-1 level was measured (pg/mL) in the blood from varicose veins twice, at the day of inclusion and after 60 days. Legs discomfort related to chronic venous disease (CVD) symptoms was measured with 10-cm Visual Analogue Scale (VAS) at inclusion and at completion of the study.

RESULTS

Median (interquartile range, IQR) MCP-1 concentrations in treatment and control groups at inclusion were 171.9 (124.4-216.0) and 157.0 (120.1-163.1), resp., P=0.285. After 60 days of treatment MCP-1 level decreased, but non-significantly to 152.3 (124.1-178.3). In patients who did not receive treatment chemokine level slightly increased to 163.0 (134.0-172.9). Median changes over time were -6.6 (-30.9-7.4) and 10.6 (-3.7-19.2) in the study and control groups, resp. (P=0.048). After 60 days in 12 of 19 and 2 of 9 patients of treatments and control groups MCP-1 decreased (P=0.103). Odds ratio for MCP-1 decreasing was 9.5 (95% CI 1.1-81.5, P=0.043) for those who received venoactive drug. Mean (± standard deviation [SD]) legs discomfort significantly dropped in the study group from 5.7 (±2.5) to 1.9 (±2.2) (P=0.0003), while in controls no changes were registered: 3.4 (±1.3) and 3.5 (± 1.4), resp., P=0.28). Mean difference of VAS at baseline and at follow-up was -3.5 (±2.6) and 0.9 (±2.1), resp. (P<0.0001).

CONCLUSIONS

Plasma concentration of MCP-1 in varicose veins blood demonstrates a tendency to decrease under two months treatment with a venoactive drug. Future studies are needed to reveal a possible role of MCP-1 as a target considering its role in varicose veins pathogenesis.

Clinical Efficacy of Endovenous Radiofrequency Ablation (RFA) for Superficial Varicose Veins of the Lower Extremities

Objective

To investigate the clinical efficacy of intravenous radiofrequency ablation (RFA) in the treatment of patients with superficial varicose veins of lower extremities.

Methods

From January 1, 2021, to January 1, 2022, 62 patients with superficial lower extremity varicose veins were selected and divided into two groups according to the treatment plan. 31 patients underwent high saphenous vein ligation and dissection as control. Thirty-one patients received RFA treatment as the experimental group. The operation-related indicators, clinical efficacy, and postoperative complications were compared.

Results

The intraoperative blood loss in the experimental group was significantly less than that in the control group. The clinical efficacy of the experimental group was significantly better than that of the control group. The incidence of postoperative complications in the experimental group was lower than that in the control group.

Conclusion

RFA has a good clinical effect in the treatment of patients with superficial lower extremity varicose veins, with less postoperative complications, and has a high therapeutic value.

Vein morphometry in end-stage kidney disease: Teasing out the contribution of age, comorbidities, and vintage to chronic wall remodeling

Background

Chronic kidney disease (CKD) is a highly comorbid condition with significant effects on vascular health and remodeling. Upper extremity veins are important in end-stage kidney disease (ESKD) due to their potential use to create vascular accesses. However, unlike arteries, the contribution of CKD-associated factors to the chronic remodeling of veins has been barely studied.

Methods

We measured morphometric parameters in 315 upper extremity veins, 131 (85% basilic) from stage 5 CKD/ESKD patients and 184 (89% basilic) from non-CKD organ donors. Associations of demographic and clinical characteristics with intimal hyperplasia (IH) and medial fibrosis were evaluated using multivariate regression models.

Results

The study cohort included 33% females, 30% blacks, 32% Hispanics, and 37% whites. Over 60% had hypertension, and 25% had diabetes independent of CKD status. Among kidney disease participants, 26% had stage 5 CKD, while 22 and 52% had ESKD with and without history of a previous arteriovenous fistula/graft (AVF/AVG), respectively. Intimal hyperplasia was associated with older age (β = 0.13 per year, confidence interval [CI] = 0.002-0.26), dialysis vintage > 12 months (β = 0.22, CI = 0.09-0.35), and previous AVF/AVG creation (β = 0.19, CI = 0.06-0.32). Upper quartile values of IH were significantly associated with diabetes (odds ratio [OR] = 2.02, CI = 1.08-3.80), which demonstrated an additive effect with previous AVF/AVG history and longer vintage in exacerbating IH. Medial fibrosis also increased as a function of age (β = 0.17, CI = 0.04-0.30) and among patients with diabetes (β = 0.15, CI = 0.03-0.28). Age was the predominant factor predicting upper quartile values of fibrosis (OR = 1.03 per year, CI = 1.01-1.05) independent of other comorbidities.

Conclusion

Age and diabetes are the most important risk factors for chronic development of venous IH and fibrosis independent of CKD status. Among kidney disease patients, longer dialysis vintage, and history of a previous AVF/AVG are strong predictors of IH.

Is There a Difference in the Clinical Efficacy of Diosmin and Micronized Purified Flavonoid Fraction for the Treatment of Chronic Venous Disorders? Review of Available Evidence

Flavonoids are oral venoactive drugs frequently prescribed to relieve the symptoms of chronic venous disorders (CVD). Among venoactive drugs, diosmin is a naturally occurring flavonoid glycoside that can be isolated from various plant sources; it can also be obtained after conversion of hesperidin extracted from citrus rinds. Micronized purified flavonoid fraction (MPFF) is a preparation that contains mainly diosmin and a small fraction of hesperidin. We performed a state-of-the-art literature review to collect and analyze well-conducted randomized clinical studies comparing diosmin - also called non-micronized or hemisynthetic diosmin - 600 mg a day and MPFF, 1000 mg a day. Three clinical studies met the criteria and were included for this literature review. These clinical studies showed a significant decrease of CVD symptom intensity (up to approximately 50%) and global patient satisfaction after one-to-six-month treatment with diosmin or MPFF, without statistical differences between these two forms of diosmin. Both treatments were well tolerated with few mild adverse drug reactions reported. Overall, based on this literature review, there is no clinical benefit to increase the dose of diosmin beyond 600 mg per day, to use the micronized form, or to add hesperidin, since clinical efficacy on venous symptomatology is achieved with 600 mg per day of pure non-micronized diosmin. This challenges the status of diosmin - 600 mg a day - in guidelines for the management of CVD, which is currently categorized 2C (weak recommendations for use and poor quality of evidence), while the most widely used and assessed preparation MPFF is rated 1B (strong recommendation for use and moderate quality of evidence).