Chronic venous disease: from symptoms to microcirculation

Reduction of lower-limb edema in patients with chronic venous disease by micronized purified flavonoid fraction: a systematic literature review and meta-analysis

INTRODUCTION

The prevalence of lower limb edema is high among patients with chronic venous disease (CVD). Several clinical studies with various designs have assessed the effect of micronized purified flavonoid fraction (MPFF) on edema. The aim of this work was to provide a comprehensive and accurate evaluation of the reduction in ankle and calf circumference as an indicator of lower limb edema reduction in patients with CVD treated with MPFF by combining studies that use different designs in a single group meta-analysis.

EVIDENCE ACQUISITION

We conducted a systematic literature review in April 2022 based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria to identify prospective studies investigating the effect of oral MPFF treatment 1000 mg/day on ankle and calf circumference in patients with CVD. Studies with population including at least one patient with an ulcer were excluded. All prospective studies irrespectively of design (i.e., interventional and non-interventional studies, randomized controlled trials (RCTs), non-randomized studies, studies without a control or reference treatment) were eligible. The Medline, Embase and Cochrane databases were searched. Endpoints were ankle and calf circumference measurements and their overall mean change from baseline estimated with random-effects meta-analysis methods. The evaluation criterion feeling of swelling was also analyzed as a standardized mean change (SMC) with 95% confidence intervals after combination of quantitative scales.

EVIDENCE SYNTHESIS

Among 861 articles identified, eight studies (five RCTs including one placebo-controlled, three non-comparative studies) met the criteria. The overall population consisted of 1635 patients, predominantly female (89% ranging from 64% to 94%) with a mean age of 47 years ranging from 41 to 48 years. Mean reduction in ankle circumference was 6.0 mm (95%CI: 3.6 to 8.4; P<0.001) and 7.0 mm (95%CI: 0.9 to 13.1; P=0.024) after two and at least six months of treatment respectively. The results were similar when considering the study type RCTs and non-RCTs. Mean reduction in calf circumference was 5.7 mm (95%CI: 2.8 to 8.6; P<0.001) and 6.7 mm (95%CI: 5.2 to 8.1; P<0.001), at two months and at the last post-baseline evaluation respectively. Heterogeneity among studies was statistically significant (degree of consistency I2=93.5%; P<0.001 and I2=81.1%, P<0.01 for ankle and calf circumference, respectively). In the three studies reporting the effect on feeling of swelling a significant standardized mean change (SMC) reduction of 2.2 (95%CI: 0.2 to 4.2; P=0.028) on a quantitative scale was observed after two months of treatment with MPFF.

CONCLUSIONS

MPFF appeared to be effective in reducing ankle and calf circumference as well as feeling of swelling irrespective of study design. The circumference reduction is present at short and long term, suggesting that benefit occurs early and is maintained overtime. Despite the observed heterogeneity among included studies, this meta-analysis supports the significant therapeutic efficacy of MPFF in reducing lower-limb edema in patients with CVD. The complete video presentation of the work is available online at www.minervamedica.it (Supplementary Digital Material 1: Supplementary Video 1, 5 min, 192 MB).

Unraveling the pathophysiology of lower-limb postthrombotic syndrome in adolescents: a proof-of-concept study

A better understanding of the pathophysiology of pediatric postthrombotic syndrome (PTS) is needed to develop strategies to treat this condition. We investigated calf pump function, exercise capacity, balance in power output, and changes in limb muscle oxygen saturation (SmO2) and fluid content during exercise in 10 pediatric patients with unilateral lower-limb PTS, and in age- and sex-matched controls (1:1-1:2 ratio). Outcomes were investigated using bioimpedance spectroscopy, torque-sensing pedals, and near-infrared spectroscopy during incremental- and constant-load cycling tests. The median age at participation was 17 years (25th-75th percentile, 15-18 years); 68% of participants were females. The median CAPTSure score in the affected leg of affected participants was 35 points (25th-75th percentile, 24-46 points), indicating moderate/severe PTS; 20% of patients had a history of central venous catheter-related thrombosis. Increasing PTS severity was associated with higher calf pump venous volume and higher ejection volume, leading to compensated calf pump performance. We found no evidence of PTS impact on exercise capacity. Leg contribution to power output was similar in affected and unaffected legs. However, the PTS-affected legs showed lower SmO2 during active cycling and recovery with increasing PTS severity, indicating impaired microvascular function in the muscle. These findings suggest that PTS severity is associated with impaired blood flow, presumably from elevated venous pressure during and after exercise. The fact that microvascular function is impaired in young patients with PTS underscores the relevance of developing strategies to mitigate the effects of this chronic vascular disease to minimize its deleterious effects as children grow older.

A nationwide study of compliance of venoactive drugs in chronic venous disease patients

Purpose

Venoactive drugs are widely used to improve the symptoms and signs of chronic venous disease. This study aimed to analyze the rate of adverse events after venoactive drug prescription and subsequent compliance and switching rates.

Methods

Using the National Health Insurance Service database, individuals with at least one chronic venous disease code between January 2009 and December 2019 were identified, and 30% (2,216,780 individuals) of these were sampled. Finally, 1,551,212 patients were included, and we analyzed adverse events, compliance, and switching rates with 8 venoactive drugs, including Vitis vinifera extract, naftazone, micronized purified flavonoid fraction, Vitis vinifera leaf extract, diosmin, diobsilate calcium, bilberry fruit dried extract, and sulodexide.

Results

The most commonly prescribed venoactive drug was Vitis vinifera extract (72.2%), followed by sulodexide (9.3%), and Vitis vinifera leaf dry extract (8.2%). Adverse event rates were significantly lower in the naftazone and diosmin groups (P = 0.001 and P = 0.002, respectively) and significantly higher in the Vitis vinifera leaf dry extract group (P = 0.009). Drug adherence to sulodexide was the highest throughout the study period, followed by billberry extract and dobesilate (all P < 0.001). For most drugs, the drug switching rate was low (<5.0%).

Conclusion

Vitis vinifera extract was the most commonly prescribed venoactive drug in Korea, and drug adherence to sulodexide was the highest among all venoactive drugs. The adverse event rates were significantly lower in the naftazone and diosmin groups.

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.

Chronic venous disease and diabetic microangiopathy: pathophysiology and commonalities

Chronic venous disease and diabetes mellitus are highly prevalent and debilitating conditions affecting millions of individuals globally. Although these conditions are typically considered as separate entities, they often co-exist which may be important in both understanding their pathophysiology and determining the best treatment strategy. Diabetes mellitus is twice as common in patients with chronic venous disease compared with the general population. Notably, a large proportion of patients with diabetes mellitus present with venous disorders, although this is often overlooked. The etiology of chronic venous disease is multifactorial, involving hemodynamic, genetic, and environmental factors which result in changes to the venous endothelium and structural wall as well as inflammation. Inflammation, endothelial dysfunction and hyperfiltration or leakage, are commonly observed in diabetes mellitus and cause various diabetic microvascular complications. Both diseases are also influenced by the increased expression of adhesion molecules, chemokines, and cytokines, and are characterized by the presence of vessel hypertension. Consequently, despite differences in etiology, the pathophysiology of both chronic venous disease and diabetic microangiopathy appears to be driven by endothelial dysfunction and inflammation. Treatment strategies should take the co-existence of chronic venous disease and diabetic microangiopathy into account. Compression therapy is recommended in inflammatory conditions that have an edema component as seen in both chronic venous disease and diabetes mellitus. Lifestyle changes like weight loss and exercise, will improve metabolic state and lower inflammation and should be promoted in these patients. Additionally, both patient populations may benefit from venoactive drugs.

Understanding Chronic Venous Disease: A Critical Overview of Its Pathophysiology and Medical Management

Chronic venous disease (CVD) is a multifactorial condition affecting an important percentage of the global population. It ranges from mild clinical signs, such as telangiectasias or reticular veins, to severe manifestations, such as venous ulcerations. However, varicose veins (VVs) are the most common manifestation of CVD. The explicit mechanisms of the disease are not well-understood. It seems that genetics and a plethora of environmental agents play an important role in the development and progression of CVD. The exposure to these factors leads to altered hemodynamics of the venous system, described as ambulatory venous hypertension, therefore promoting microcirculatory changes, inflammatory responses, hypoxia, venous wall remodeling, and epigenetic variations, even with important systemic implications. Thus, a proper clinical management of patients with CVD is essential to prevent potential harms of the disease, which also entails a significant loss of the quality of life in these individuals. Hence, the aim of the present review is to collect the current knowledge of CVD, including its epidemiology, etiology, and risk factors, but emphasizing the pathophysiology and medical care of these patients, including clinical manifestations, diagnosis, and treatments. Furthermore, future directions will also be covered in this work in order to provide potential fields to explore in the context of CVD.

Exposure to acute normobaric hypoxia results in adaptions of both the macro- and microcirculatory system

Although acute hypoxia is of utmost pathophysiologic relevance in health and disease, studies on its effects on both the macro- and microcirculation are scarce. Herein, we provide a comprehensive analysis of the effects of acute normobaric hypoxia on human macro- and microcirculation. 20 healthy participants were enrolled in this study. Hypoxia was induced in a normobaric hypoxia chamber by decreasing the partial pressure of oxygen in inhaled air stepwisely (pO₂; 21.25 kPa (0 k), 16.42 kPa (2 k), 12.63 kPa (4 k) and 9.64 kPa (6 k)). Macrocirculatory effects were assessed by cardiac output measurements, microcirculatory changes were investigated by sidestream dark-field imaging in the sublingual capillary bed and videocapillaroscopy at the nailfold. Exposure to hypoxia resulted in a decrease of systemic vascular resistance (p < 0.0001) and diastolic blood pressure (p = 0.014). Concomitantly, we observed an increase in heart rate (p < 0.0001) and an increase of cardiac output (p < 0.0001). In the sublingual microcirculation, exposure to hypoxia resulted in an increase of total vessel density, proportion of perfused vessels and perfused vessel density. Furthermore, we observed an increase in peripheral capillary density. Exposure to acute hypoxia results in vasodilatation of resistance arteries, as well as recruitment of microvessels of the central and peripheral microcirculation. The observed macro- and microcirculatory effects are most likely a result from compensatory mechanisms to ensure adequate tissue oxygenation.

CEAP clinical classes C0S-C4: differences, similarities and role of Ruscus + HMC + vitamin C in patients with chronic venous disease

Since the publication of the CEAP classification, new research has enriched our knowledge; notably on the heritability of CVD and the genetic and environmental factors involved in this condition, as well as the symptoms apparent within the spectrum of the CEAP clinical classes and the benefits of medical treatment. Using the CEAP classification as a special theme, a symposium with the same title as the present paper was held at the annual meeting of the 2019 European Venous Forum. The lectures presented much valuable information, from which some key points can be extracted. The influence of environmental factors was demonstrated, and the fact that a large amount of information can be obtained from comprehensive history taking. There is robust evidence for heritability. Many candidate genes/loci have been identified, potentially offering new targets for treatment. More research is needed, notably using genome-wide association studies and also on microbiota, which may play a role in CVD through the inflammation pathway. Ruscus + HMC + vitamin C acts by increasing venous and lymphatic tone, protecting microcirculation, and reducing inflammation. It improves quality of life in C0S to C3 CVD patients, while a review of clinical studies and a meta-analysis have confirmed its clinical efficacy across a wide spectrum of CVD clinical classes: C0S, C1S, C2, C3 and C4. It has been awarded a Grade 1A recommendation by the international guidelines.

Expert consensus on the conservative management of patients with chronic venous disease in CEAP clinical classes C0s-C3 in Italy

OBJECTIVES

To define a consensual approach for the conservative treatment of patients C0s-C3.

METHOD

The project was structured into two phases. The first one involved a group of Italian specialists in angiology and/or vascular surgery with the aim to compare their therapeutic choices in the management of patients in CEAP C0s-C3. The second phase used a Delphi consensus in order to elaborate practical statements on the conservative management of these patients.

RESULTS

The first phase involved a group of 166 Italian specialists while the second phase involved a Steering Committee of 6 specialists and a panel of 20 specialists. At the end of the third round, a consensus >80% was reached on seven assertions.

CONCLUSION

Seven statements have been drafted by a group of Italian specialists to provide physicians with practical guidance for the conservative treatment of C0s-C3 patients. Outstanding issues on the management of these patients were identified, confirming the urgent need of further research.