Chronic venous insufficiency: a new concept to understand pathophysiology at the microvascular level - a pilot study

Optical coherence tomography angiography enables visualization of microvascular patterns in chronic venous insufficiency

Chronic venous insufficiency (CVI) is a global health concern with significant public health and individual impact. Currently available diagnostic methods cannot visualize microvenous pathologies that have shown to result in severe forms of CVI and also affect the skin. Optical coherence tomography angiography (OCTA) may close the CVI diagnostic gap by providing a fast, label-free, and non-invasive solution to visualize cutaneous microvasculature. The study enlisted 66 subjects, including 53 CVI patients spanning all clinical-etiology-anatomic-pathophysiologic (CEAP) C stages and 13 healthy controls. The high spatial resolution OCTA system used was specifically designed for skin imaging. Significant microangiographic pattern variations emerged, both in qualitative and quantitative terms. OCTA provided valuable insights into cutaneous microvascular changes among different CVI stages. Thereby, OCTA may enable the selection of patient populations at risk for disease progression in the future.

Pathophysiology and Genetic Associations of Varicose Veins: A Narrative Review

Varicose veins (VVs) have a high prevalence worldwide and have become a major medical burden. Their pathophysiology involves a complex interplay of inflammation and tissue remodeling, and current treatment is limited by its impact on the pathophysiological mechanisms. In addition, despite clear environmental factors, family history is an important risk factor, suggesting a genetic component to the risk of developing VVs. Our understanding of the pathogenesis of these diseases has benefited greatly from the expansion of population genetic studies, from pioneering family studies to large genome-wide association studies; we now find multiple risk loci for each venous disease. This review considers the pathophysiology of VVs, highlighting the current state of genetic knowledge. We also propose future directions for research.

Nursing diagnosis proposal "Impaired Peripheral Venous Return": concept formation

OBJECTIVES

to develop a nursing diagnosis proposal focused on venous return.

METHODS

this is a concept analysis according to the model proposed by Walker and Avant, which is operationalized through an integrative review. The study was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol recommendations.

RESULTS

the analysis of the 131 studies allowed identifying attributes, antecedents and consequences. The most common attribute was decreased venous flow. The antecedents most frequently found were structural and/or functional valve deficiency, advanced age and peripheral venous thrombosis. The most common consequences were peripheral edema, venous ulcer and pain in the extremity.

CONCLUSIONS

the formulated nursing diagnosis was proposed as part of Domain 4, Activity/rest, in Class 4, Cardiovascular/pulmonary responses, with eight defining characteristics, five related factors, six at-risk populations and four associated conditions.

Physical exercise for the treatment of non-ulcerated chronic venous insufficiency

BACKGROUND

Chronic venous insufficiency (CVI) is a condition related to chronic venous disease that may progress to venous leg ulceration and impair quality of life of those affected. Treatments such as physical exercise may be useful to reduce CVI symptoms. This is an update of an earlier Cochrane Review.

OBJECTIVES

To evaluate the benefits and harms of physical exercise programmes for the treatment of individuals with non-ulcerated CVI.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 28 March 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing exercise programmes with no exercise in people with non-ulcerated CVI.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were intensity of disease signs and symptoms, ejection fraction, venous refilling time, and incidence of venous leg ulcer. Our secondary outcomes were quality of life, exercise capacity, muscle strength, incidence of surgical intervention, and ankle joint mobility. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included five RCTs involving 146 participants. The studies compared a physical exercise group with a control group that did not perform a structured exercise programme. The exercise protocols differed between studies. We assessed three studies to be at an overall unclear risk of bias, one study at overall high risk of bias, and one study at overall low risk of bias. We were not able to combine data in meta-analysis as studies did not report all outcomes, and different methods were used to measure and report outcomes. Two studies reported intensity of CVI disease signs and symptoms using a validated scale. There was no clear difference in signs and symptoms between groups in baseline to six months after treatment (Venous Clinical Severity Score mean difference (MD) -0.38, 95% confidence interval (CI) -3.02 to 2.26; 28 participants, 1 study; very low-certainty evidence), and we are uncertain if exercise alters the intensity of signs and symptoms eight weeks after treatment (MD -4.07, 95% CI -6.53 to -1.61; 21 participants, 1 study; very low-certainty evidence). There was no clear difference in ejection fraction between groups from baseline to six months follow-up (MD 4.88, 95% CI -1.82 to 11.58; 28 participants, 1 study; very low-certainty evidence). Three studies reported on venous refilling time. We are uncertain if there is an improvement in venous refilling time between groups for baseline to six-month changes (MD 10.70 seconds, 95% CI 8.86 to 12.54; 23 participants, 1 study; very low-certainty evidence) or baseline to eight-week change (MD 9.15 seconds, 95% CI 5.53 to 12.77 for right side; MD 7.25 seconds, 95% CI 5.23 to 9.27 for left side; 21 participants, 1 study; very low-certainty evidence). There was no clear difference in venous refilling index for baseline to six-month changes (MD 0.57 mL/min, 95% CI -0.96 to 2.10; 28 participants, 1 study; very low-certainty evidence). No included studies reported the incidence of venous leg ulcers. One study reported health-related quality of life using validated instruments (Venous Insufficiency Epidemiological and Economic Study (VEINES) and 36-item Short Form Health Survey (SF-36), physical component score (PCS) and mental component score (MCS)). We are uncertain if exercise alters baseline to six-month changes in health-related quality of life between groups (VEINES-QOL: MD 4.60, 95% CI 0.78 to 8.42; SF-36 PCS: MD 5.40, 95% CI 0.63 to 10.17; SF-36 MCS: MD 0.40, 95% CI -3.85 to 4.65; 40 participants, 1 study; all very low-certainty evidence). Another study used the Chronic Venous Disease Quality of Life Questionnaire (CIVIQ-20), and we are uncertain if exercise alters baseline to eight-week changes in health-related quality of life between groups (MD 39.36, 95% CI 30.18 to 48.54; 21 participants, 1 study; very low-certainty evidence). One study reported no differences between groups without presenting data. There was no clear difference between groups in exercise capacity measured as time on treadmill (baseline to six-month changes) (MD -0.53 minutes, 95% CI -5.25 to 4.19; 35 participants, 1 study; very low-certainty evidence). We are uncertain if exercise improves exercise capacity as assessed by the 6-minute walking test (MD 77.74 metres, 95% CI 58.93 to 96.55; 21 participants, 1 study; very low-certainty evidence). Muscle strength was measured using dynamometry or using heel lifts counts. We are uncertain if exercise increases peak torque/body weight (120 revolutions per minute) (changes from baseline to six months MD 3.10 ft-lb, 95% CI 0.98 to 5.22; 29 participants, 1 study; very low-certainty evidence). There was no clear difference between groups in baseline to eight-week change in strength measured by a hand dynamometer (MD 12.24 lb, 95% CI -7.61 to 32.09 for the right side; MD 11.25, 95% CI -14.10 to 36.60 for the left side; 21 participants, 1 study; very low-certainty evidence). We are uncertain if there is an increase in heel lifts (n) (baseline to six-month changes) between groups (MD 7.70, 95% CI 0.94 to 14.46; 39 participants, 1 study; very low-certainty evidence). There was no clear difference between groups in ankle mobility measured during dynamometry (baseline to six-month change MD -1.40 degrees, 95% CI -4.77 to 1.97; 29 participants, 1 study; very low-certainty evidence). We are uncertain if exercise increases plantar flexion measured by a goniometer (baseline to eight-week change MD 12.13 degrees, 95% CI 8.28 to 15.98 for right leg; MD 10.95 degrees, 95% CI 7.93 to 13.97 for left leg; 21 participants, 1 study; very low-certainty evidence). In all cases, we downgraded the certainty of evidence due to risk of bias and imprecision.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to assess the benefits and harms of physical exercise in people with chronic venous disease. Future research into the effect of physical exercise should consider types of exercise protocols (intensity, frequency, and time), sample size, blinding, and homogeneity according to the severity of disease.

Varicose Veins and Chronic Venous Disease

Chronic venous disease is a worldwide problem associated with significant morbidity and is expected to increase in prevalence as the current population ages. This is a comprehensive review of the anatomy, pathophysiology, genomics, clinical classification, and treatment modalities of chronic venous disease.

A Novel Tool for a Challenging Disease: Stasis Leg Ulcers Assessed Using QFlow in Triggered Angiography Noncontrast Enhanced Magnetic Resonance Imaging

Imaging characteristics of stasis leg ulcers (SLUs) are not easily demonstrated through existing diagnostic tools. Early diagnosis and treatment are crucial. This pilot study was conducted to assess the quantitative flow (QFlow) in triggered angiography noncontrast enhanced (TRANCE) magnetic resonance imaging (MRI) to identify the hemodynamics of victims with stasis leg ulcers (SLUs). This study included 33 patients with SLUs and 14 healthy controls (HC). The 33 patients with SLUs were divided into a reflux (15 patients) and a nonreflux group (18 patients). QFlow was done in the reflux, the nonreflux, and the HC. The stroke volume (SV), forward flow volume (FFV), absolute flow volume (AFV), mean flow (MF), and mean velocity (MV) were higher in the reflux than in the HC group in most segments, namely the external iliac vein (EIV), popliteal vein (PV), and great saphenous vein (GSV) (SV, p = 0.008; FFV, p = 0.008; absolute stroke volume (ASV), p = 0.008; MF, p = 0.002; MV, p = 0.009). No differences in the QFlow patterns were found in the GSV segment between the nonreflux group and the HC. Excellent performance in discriminating SLU with superficial venous reflux was reported for SV in the EIV and the PV (area under the curve (AUC) = 0.851 and 0.872), FFV in the EIV and PV (AUC = 0.854 and 0.869), ASV in the EIV and PV (AUC = 0.848 and 0.881), and MF in the EIV and PV (AUC = 0.866 and 0.868). The cutoff levels of SV/FFV/ASV/MF in the EIV/FV/PV/GSV for discriminating the SLU with superficial venous reflux were identified (p < 0.005). In conclusion, SLUs present different QFlow patterns by different etiology. The QFlow parameters of all vessel segments were higher in the morbid limbs of the reflux group than HC. The GSV segment of the nonreflux group displayed a pattern like the HC.

Nrf2-activating Therapy Accelerates Wound Healing in a Model of Cutaneous Chronic Venous Insufficiency

Supplemental Digital Content is available in the text.

Background

Chronic venous insufficiency (CVI) stems from venous hypertension, extravasation of blood, and iron-rich skin deposits. The latter is central to ulcer development through generating reactive oxygen species (ROS) that drive persistent local inflammation and the development of lipodermatosclerosis. The ability to study CVI cutaneous inflammation is fundamental to advancing therapies. To address this end, a novel protocol was adapted to investigate cutaneous wound healing in iron-induced inflammation.

Methods:

Mice were injected subcutaneously or intraperitoneally with iron-dextran, and excisional wounding was performed. Histologic and biomolecular analysis was performed.

Results:

Iron loading was associated with dense iron deposits similar to those in chronic venous stasis. Subcutaneous but not intraperitoneal loading resulted in dermal collagen expansion. Iron overload was associated with atypical antioxidant expression as compared to vehicle controls (p < 0.0001) as well as delayed wound healing by 3-4 days. A potent activator of Nuclear factor erythroid 2-related factor 2 (Nrf2), a major transcriptional regulator of redox status, was applied to establish therapeutic efficacy. Nrf2 activation in the wound resulted in significant reduction of closure times across all experimental arms. Antioxidant expression following topical treatment was significantly increased for intraperitoneally iron-loaded mice (p < 0.0001) but did not achieve significance for the subcutaneously-loaded animals.

Conclusions:

We have characterized a novel model of cutaneous iron-overload designed to advance our understanding of dysfunctional wound healing in CVI. Cutaneous changes of iron overload coincide with redox imbalance and delayed wound healing. By activating Nrf2, we demonstrate the regenerative potential of pro-antioxidant mediators in treating CVI related wound complications.

Stasis Leg Ulcers: Venous System Revises by Triggered Angiography Non-Contrast-Enhanced Sequence Magnetic Resonance Imaging

Objectives: The distribution of venous pathology in stasis leg ulcers is unclear. The main reason for this uncertainty is the lack of objective diagnostic tools. To fill this gap, we assessed the effectiveness of triggered angiography non-contrast-enhanced (TRANCE)-magnetic resonance imaging (MRI) in determining the venous status of patients with stasis leg ulcers. Methods: This prospective observational study included the data of 23 patients with stasis leg ulcers who underwent TRANCE-MRI between April 2017 and May 2020; the data were retrospectively analyzed. TRANCE MRI utilizes differences in vascular signal intensity during the cardiac cycle for subsequent image subtraction, providing not only a venogram but also an arteriogram without the use of contrast agents or radiation. Results: TRANCE MRI revealed that the stasis leg ulcers of nine of the 23 patients could be attributed to valvular insufficiency and venous occlusion (including deep venous thrombosis [DVT], May–Thurner syndrome, and other external compression). Moreover, TRANCE MRI demonstrated no venous pathology in five patients (21.7%). We analyzed TRANCE MRI hemodynamic parameters, namely stroke volume, forward flow volume, backward flow volume, regurgitant fraction, absolute volume, mean flux, stroke distance, and mean velocity, in the external iliac vein, femoral vein, popliteal vein, and great saphenous vein (GSV) in three of the patients with valvular insufficiency and three of those with venous occlusion. We found that the mean velocity and stroke volume in the GSV was higher than that in the popliteal vein in all patients with venous valvular insufficiency. Conclusions: Stasis leg ulcers may have no underlying venous disease and could be confirmed by TRANCE-MRI. TRANCE MRI has good Interrater reliability between Duplex study in greater saphenous venous insufficiency. It also potentially surpasses existing diagnostic modalities in terms of distinguishable hemodynamic figures. Accordingly, TRANCE-MRI is a safe and useful tool for examining stasis leg ulcers and is extensively applied currently.

A scoping review on Chronic Venous Disease and the development of a Venous Leg Ulcer: The role of obesity and mobility

OBJECTIVE

The risk factors obesity and reduced mobility are not well known in the development of a Venous Leg Ulcer (VLU). The aim of this scoping review is to explore the mechanisms by which obesity and reduced mobility contribute the development of a VLU in patients with Chronic Venous Disease (CVD).

METHODS

For this scoping review a search was performed in May 2019 in the Cochrane Library and Pubmed to identify studies on the working mechanisms of obesity and mobility in developing a VLU. Hand searches were performed to find additional studies explaining the working mechanisms (indirectly related to the VLU). Two reviewers independently reviewed the abstracts and full-text articles.

RESULTS

Twenty-eight studies met our eligibility criteria. Disturbed range of ankle motion and gait can lead to a reduced Calf Muscle Pump (CMP) function which leading to a venous outflow disorder. Increased abdominal pressure due to obesity can lead to a venous outflow obstruction and increased adipose tissue mass results in an increase in adipokine secretion. The venous outflow disorder, outflow obstruction and increased adipokine secretion can all lead to chronic systemic inflammation, increased endothelial permeability and hence microcirculatory dysfunction. This alone can result in a VLU.

CONCLUSION

Obesity and reduced mobility can lead to a reduction of the CMP function, an increase in abdominal pressure and an increase in adipose tissue mass. This can simultaneously lead to haemodynamic changes in the macro- and microcirculation of the lower extremities and eventually in a VLU. In patients with obesity and reduced mobility the microcirculation alone can lead to skin changes and eventually a VLU. Therefore, early recognition of CVD symptoms in patients with obesity and reduced mobility is crucial to diagnose and treat CVD to prevent a VLU.