Predicting wound complications following lower extremity revascularization

OBJECTIVE

The aim of this study was to create a simple risk score to identify factors associated with wound complications after infrainguinal revascularization.

METHODS

The Veterans Affairs Surgical Quality Improvement Program national data set was queried from 2005 to 2021 to identify 22,114 patients undergoing elective open revascularization for peripheral arterial disease (claudication, rest pain, tissue loss) or peripheral aneurysm. Emergency and trauma cases were excluded. The data set was divided into a two-thirds derivation set and one-third validation set to create a risk prediction model. The primary end point was wound complication (wound dehiscence, superficial/deep wound surgical site infection). Eight independent risk factors for wound complications resulted from the model and were assigned whole number integer risk scores. Summary risk scores were collapsed into categories and defined as low (0-3 points), moderate (4-7 points), high (8-11 points), and very high (>12 points).

RESULTS

The wound complication rate in the derivation data set was 9.7% (n = 1428). Predictors of wound complication included age ≤73 (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.08-1.46), body mass index ≥35 kg/m2 (OR, 1.99; 95% CI, 1.68-2.36), non-Hispanic White (vs others: OR, 1.48; 95% CI, 1.30-1.69), diabetes (OR, 1.23; 95% CI, 1.10-1.37), white blood cell count >9900/mm3 (OR, 1.18; 95% CI, 1.03-1.35), absence of coronary artery disease (OR, 1.27; 95% CI, 1.03-1.35), operative time >6 hours (OR, 1.20; 95% CI, 1.05-1.37), and undergoing a femoral endarterectomy in conjunction with bypass (OR, 1.34; 95% CI, 1.14-1.57). In both the derivation and validation sets, wound complications correlated with risk category. Among the defined categories in the derivation set, wound complication rates were 4.5% for low-risk patients, 8.5% for moderate-risk patients, 13.8% for high-risk patients, and 23.8% for very high-risk patients, with similar results for the internal validation data set. Operative indication did not independently associate with wound complications. Patients with wound complications had higher rates of reoperation and graft failure.

CONCLUSIONS

This risk prediction model uses easily obtainable clinical metrics that allow for informed discussion of wound complication risk for patients undergoing open infrainguinal revascularization.

Venous compression syndromes in females: A descriptive review

Venous compression syndromes have been described, yet the role of sex is poorly understood. Although iliac vein compression has been discussed more often with the advent of newer technologies, research has fallen short on defining epidemiology, best practices for evaluation and treatment, and differences in responses to treatment between men and females. The authors report on iliac vein compression, nonthrombotic renal vein compression, and other venous compression syndromes in females. Literature searches of PubMed were performed using the following keywords: females/females and May Thurner, venous stenting, venous outcomes, deep venous disease, deep venous compression, venous stenting, renal vein compression, renal vein surgery/stent, popliteal vein entrapment, venous thoracic vein entrapment, and popliteal vein entrapment. The articles prompted the authors to research further as the referenced articles were reviewed. Sex representation has not been addressed adequately in the research of venous compression syndromes, making the discussion of best treatment options and long-term outcomes difficult. More specific understanding of epidemiology and response to interventions will only come from research that addresses these issues directly, understanding that some of these syndromes occur rarely.

Effect of a Decision Aid on Agreement Between Patient Preferences and Repair Type for Abdominal Aortic Aneurysm: A Randomized Clinical Trial

Importance

Patients with abdominal aortic aneurysm (AAA) can choose open repair or endovascular repair (EVAR). While EVAR is less invasive, it requires lifelong surveillance and more frequent aneurysm-related reinterventions than open repair. A decision aid may help patients receive their preferred type of AAA repair.

Objective

To determine the effect of a decision aid on agreement between patient preference for AAA repair type and the repair type they receive.

Design, Setting, and Participants

In this cluster randomized trial, 235 patients were randomized at 22 VA vascular surgery clinics. All patients had AAAs greater than 5.0 cm in diameter and were candidates for both open repair and EVAR. Data were collected from August 2017 to December 2020, and data were analyzed from December 2020 to June 2021.

Interventions

Presurgical consultation using a decision aid vs usual care.

Main Outcomes and Measures

The primary outcome was the proportion of patients who had agreement between their preference and their repair type, measured using χ2 analyses, κ statistics, and adjusted odds ratios.

Results

Of 235 included patients, 234 (99.6%) were male, and the mean (SD) age was 73 (5.9) years. A total of 126 patients were enrolled in the decision aid group, and 109 were enrolled in the control group. Within 2 years after enrollment, 192 (81.7%) underwent repair. Patients were similar between the decision aid and control groups by age, sex, aneurysm size, iliac artery involvement, and Charlson Comorbidity Index score. Patients preferred EVAR over open repair in both groups (96 of 122 [79%] in the decision aid group; 81 of 106 [76%] in the control group; P = .60). Patients in the decision aid group were more likely to receive their preferred repair type than patients in the control group (95% agreement [93 of 98] vs 86% agreement [81 of 94]; P = .03), and κ statistics were higher in the decision aid group (κ = 0.78; 95% CI, 0.60-0.95) compared with the control group (κ = 0.53; 95% CI, 0.32-0.74). Adjusted models confirmed this association (odds ratio of agreement in the decision aid group relative to control group, 2.93; 95% CI, 1.10-7.70).

Conclusions and Relevance

Patients exposed to a decision aid were more likely to receive their preferred AAA repair type, suggesting that decision aids can help better align patient preferences and treatments in major cardiovascular procedures.

Trial Registration

ClinicalTrials.gov Identifier: NCT03115346.

The American Venous Forum, American Vein and Lymphatic Society and the Society for Vascular Medicine expert opinion consensus on lymphedema diagnosis and treatment

BACKGROUND

Lymphedema imposes a significant economic and social burden in modern societies. Controversies about its risk factors, diagnosis, and treatment permeate the literature. The goal of this study was to assess experts' opinions on the available literature on lymphedema while following the Delphi methodology.

METHODS

In December of 2019, the American Venous Forum created a working group tasked to develop a consensus statement regarding current practices for the diagnosis and treatment of lymphedema. A panel of experts was identified by the working group. The working group then compiled a list of clinical questions, risk factors, diagnosis and evaluation, and treatment of lymphedema. Fifteen questions that met the criteria for consensus were included in the list. Using a modified Delphi methodology, six questions that received between 60% and 80% of the votes were included in the list for the second round of analysis. Consensus was reached whenever >70% agreement was achieved.

RESULTS

The panel of experts reached consensus that cancer, infection, chronic venous disease, and surgery are risk factors for secondary lymphedema. Consensus was also reached that clinical examination is adequate for diagnosing lymphedema and that all patients with chronic venous insufficiency (C3-C6) should be treated as lymphedema patients. No consensus was reached regarding routine clinical practice use of radionuclide lymphoscintigraphy as a mandatory diagnostic tool. However, the panel came to consensus regarding the importance of quantifying edema in all patients (93.6% in favor). In terms of treatment, consensus was reached favoring the regular use of compression garments to reduce lymphedema progression (89.4% in favor, 10.6% against; mean score of 79), but the use of Velcro devices as the first line of compression therapy did not reach consensus (59.6% in favor vs 40.4% against; total score of 15). There was agreement that sequential pneumatic compression should be considered as adjuvant therapy in the maintenance phase of treatment (91.5% in favor vs. 8.5% against; mean score of 85), but less so in its initial phases (61.7% in favor vs. 38.3% against; mean score of 27). Most of the panel agreed that manual lymphatic drainage should be a mandatory treatment modality (70.2% in favor), but the panel was split in half regarding the proposal that reductive surgery should be considered for patients with failed conservative treatment.

CONCLUSION

This consensus process demonstrated that lymphedema experts agree on the majority of the statements related to risk factors for lymphedema, and the diagnostic workup for lymphedema patients. Less agreement was demonstrated on statements related to treatment of lymphedema. This consensus suggests that variability in lymphedema care is high even among the experts. Developers of future practice guidelines for lymphedema should consider this information, especially in cases of low-level evidence that supports practice patterns with which the majority of experts disagree.

Peri-Procedural Management of Hemodynamic Instability in Patients Undergoing Carotid Revascularization

Acute perioperative changes in arterial pressure occur frequently, particularly in patients with cardiovascular disease or those receiving vasoactive medications, or in relation to certain cardiovascular surgical procedures. Hemodynamic Instability (HI) are common in patients undergoing carotid revascularization because of unique patho-physiological and surgical factors. The operation, by necessity, disrupts the afferent pathway of the baroreflex, which can lead to postendarterectomy HI. Poor arterial pressure control is associated with increased morbidity and mortality after carotid revascularization, but good control of arterial pressure is often difficult to achieve in practice. The incidence, implications, and etiology of HI associated with carotid surgery are reviewed, and some recommendations made for its management. Close monitoring and titration of therapy are probably the most important considerations rather than specific choice of agents.

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

Chronic venous disease (CVD) is a common venous disorder of the lower extremities. CVD can be manifested as varicose veins (VVs), with dilated and tortuous veins, dysfunctional valves and venous reflux. If not adequately treated, VVs could progress to chronic venous insufficiency (CVI) and lead to venous leg ulcer (VLU). Predisposing familial and genetic factors have been implicated in CVD. Additional environmental, behavioral and dietary factors including sedentary lifestyle and obesity may also contribute to CVD. Alterations in the mRNA expression, protein levels and proteolytic activity of matrix metalloproteinases (MMPs) have been detected in VVs and VLU. MMP expression/activity can be modulated by venous hydrostatic pressure, hypoxia, tissue metabolites, and inflammation. MMPs in turn increase proteolysis of different protein substrates in the extracellular matrix particularly collagen and elastin, leading to weakening of the vein wall. MMPs could also promote venous dilation by increasing the release of endothelium-derived vasodilators and activating potassium channels, leading to smooth muscle hyperpolarization and relaxation. Depending on VVs severity, management usually includes compression stockings, sclerotherapy and surgical removal. Venotonics have also been promoted to decrease the progression of VVs. Sulodexide has also shown benefits in VLU and CVI, and recent data suggest that it could improve venous smooth muscle contraction. Other lines of treatment including induction of endogenous tissue inhibitors of metalloproteinases (TIMPs) and administration of exogenous synthetic inhibitors of MMPs are being explored, and could provide alternative strategies in the treatment of CVD.

Sulodexide in the Treatment of Patients with Early Stages of COVID-19: A Randomized Controlled Trial

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may induce several vascular endothelial-dependent systemic complications, and sulodexide has pleiotropic actions on the vascular endothelium, which may prove beneficial. We aimed to assess the effect of sulodexide when used within 3 days of coronavirus disease 2019 (COVID-19) clinical onset. We conducted a randomized placebo-controlled outpatient trial. To be included, patients must have been at high risk for severe clinical progression. Participants received sulodexide (oral 1,000 LRU/d) or placebo for 21 days. The primary endpoint was the need for hospital care. Also assessed were patients' need for supplemental oxygen as well as D-dimer and C-reactive protein (CRP) levels, thromboembolic events, major bleeding, and mortality. A total of 243 patients were included in the per-protocol analysis from June 5 to August 30, 2020. Of these, 124 received sulodexide and 119 received a placebo. Only 17.7% of the patients in the sulodexide group required hospitalization, compared with 29.4% in the placebo group (p = 0.03). This benefit persisted in the intention-to-treat analysis (15% in sulodexide group vs. 24% with placebo [p = 0.04]). With sulodexide, fewer patients required supplemental oxygen (30 vs. 42% [p = 0.05]). After 2 weeks, fewer patients had D-dimer levels >500 ng/dL (22 vs. 47% [p < 0.01]), and patients also had lower mean CRP levels (12.5 vs. 17.8 mg/dL [p < 0.01]). There were no between-group differences in thromboembolic events, major bleeding, or mortality. Treatment of COVID-19 patients with sulodexide, when provided within 3 days of clinical onset, improved their clinical outcomes. Although the results should be confirmed, sulodexide could be valuable in an outpatient setting.

Why Venous Leg Ulcers Have Difficulty Healing: Overview on Pathophysiology, Clinical Consequences, and Treatment

Venous leg ulcers (VLUs) are one of the most common ulcers of the lower extremity. VLU affects many individuals worldwide, could pose a significant socioeconomic burden to the healthcare system, and has major psychological and physical impacts on the affected individual. VLU often occurs in association with post-thrombotic syndrome, advanced chronic venous disease, varicose veins, and venous hypertension. Several demographic, genetic, and environmental factors could trigger chronic venous disease with venous dilation, incompetent valves, venous reflux, and venous hypertension. Endothelial cell injury and changes in the glycocalyx, venous shear-stress, and adhesion molecules could be initiating events in VLU. Increased endothelial cell permeability and leukocyte infiltration, and increases in inflammatory cytokines, matrix metalloproteinases (MMPs), reactive oxygen and nitrogen species, iron deposition, and tissue metabolites also contribute to the pathogenesis of VLU. Treatment of VLU includes compression therapy and endovenous ablation to occlude the axial reflux. Other interventional approaches such as subfascial endoscopic perforator surgery and iliac venous stent have shown mixed results. With good wound care and compression therapy, VLU usually heals within 6 months. VLU healing involves orchestrated processes including hemostasis, inflammation, proliferation, and remodeling and the contribution of different cells including leukocytes, platelets, fibroblasts, vascular smooth muscle cells, endothelial cells, and keratinocytes as well as the release of various biomolecules including transforming growth factor-β, cytokines, chemokines, MMPs, tissue inhibitors of MMPs (TIMPs), elastase, urokinase plasminogen activator, fibrin, collagen, and albumin. Alterations in any of these physiological wound closure processes could delay VLU healing. Also, these histological and soluble biomarkers can be used for VLU diagnosis and assessment of its progression, responsiveness to healing, and prognosis. If not treated adequately, VLU could progress to non-healed or granulating VLU, causing physical immobility, reduced quality of life, cellulitis, severe infections, osteomyelitis, and neoplastic transformation. Recalcitrant VLU shows prolonged healing time with advanced age, obesity, nutritional deficiencies, colder temperature, preexisting venous disease, deep venous thrombosis, and larger wound area. VLU also has a high, 50-70% recurrence rate, likely due to noncompliance with compression therapy, failure of surgical procedures, incorrect ulcer diagnosis, progression of venous disease, and poorly understood pathophysiology. Understanding the molecular pathways underlying VLU has led to new lines of therapy with significant promise including biologics such as bilayer living skin construct, fibroblast derivatives, and extracellular matrices and non-biologic products such as poly-N-acetyl glucosamine, human placental membranes amnion/chorion allografts, ACT1 peptide inhibitor of connexin 43, sulodexide, growth factors, silver dressings, MMP inhibitors, and modulators of reactive oxygen and nitrogen species, the immune response and tissue metabolites. Preventive measures including compression therapy and venotonics could also reduce the risk of progression to chronic venous insufficiency and VLU in susceptible individuals.

Design of the PReferences for Open Versus Endovascular Repair of Abdominal Aortic Aneurysm (PROVE-AAA) Trial

For patients with abdominal aortic aneurysm (AAA), randomized trials have found endovascular AAA repair (EVAR) is associated with lower perioperative morbidity and mortality than open surgical repair (OSR). However, OSR has fewer long-term aneurysm-related complications, such as endoleak or late rupture. Patients treated with EVAR and OSR have similar survival rates within two years after surgery, and OSR does not require intensive surveillance. Few have examined if patient preferences are aligned with the type of treatment they receive for their AAA. Although many assume that patients may universally prefer the less-invasive nature of EVAR, our preliminary work suggests that patients who value the lower risk of late complications may prefer OSR. In this study, called The PReferences for Open Versus Endovascular Repair of Abdominal Aortic Aneurysm (PROVE-AAA) trial, we describe a cluster-randomized trial to test if a decision aid can better align patients' preferences and their treatment type for AAA. Patients enrolled in the study are candidates for either endovascular or open repair and are followed up at VA hospitals by vascular surgery teams who regularly perform both types of repair. In Aim 1, we will determine patients' preferences for endovascular or open repair and identify domains associated with each repair type. In Aim 2, we will assess alignment between patients' preferences and the repair type elected and then compare the impact of a decision aid on this alignment between the intervention and control groups. This study will help us to accomplish two goals. First, we will better understand the factors that affect patient preference when choosing between EVAR and OSR. Second, we will better understand if a decision aid can help patients be more likely to receive the treatment strategy they prefer for their AAA. Study enrollment began on June 1, 2017. Between June 1, 2017 and November 1, 2018, we have enrolled 178 of a total goal of 240 veterans from 20 VA medical centers and their vascular surgery teams across the country. We anticipate completing enrollment in PROVE-AAA in June 2019, and study analyses will be performed thereafter.

Patient information sources when facing repair of abdominal aortic aneurysm

OBJECTIVE

Shared medical decision making is most important when there are competing options for repair such as in treatment of abdominal aortic aneurysm (AAA). We sought to understand the sources of patients' pre-existing knowledge about AAA to better inform treating physicians about patients' needs for preoperative counseling.

METHODS

We performed a multicenter survey of patients facing AAA repair at 20 Veterans Affairs hospitals across the United States as part of the Preferences for Open Versus Endovascular Repair of AAA study. A validated survey instrument was administered to examine the sources of information available and commonly used by patients to learn about their repair options. The survey was administered by study personnel before the patient had any interaction with the vascular surgeon because survey data were collected before the vascular clinic visit.

RESULTS

Preliminary analysis of data from 99 patients showed that our cohort was primarily male (99%) and elderly (mean age 73 years). Patients commonly had a history of hypertension (86%), prior myocardial infarction (32%), diabetes (32%), and were overweight (58%). Patients arrived at their surgeon's office appointment with limited information. A majority of patients (52%) reported that they had not talked to their primary care physician at all about their options for AAA repair, and one-half (50%) reported that their view of the different surgical options had not been influenced by anyone. Slightly less than one-half of patients reported that they did not receive any information about open surgical aneurysm repair and endovascular aortic aneurysm repair (41% and 37%, respectively). Few patients indicated using the internet as their main source of information about open surgical aneurysm repair and endovascular aortic aneurysm repair (10% and 11%, respectively).

CONCLUSIONS

Patients are commonly referred for AAA repair having little to no information regarding AAA pathology or repair options. Fewer than one in five patients searched the internet or had accessed other sources of information on their own. Most vascular surgeons should assume that patients will present to their first vascular surgery appointment with minimal understanding of the treatment options available to them.

Case-control evaluation of the impact of below 20 mmHg elastic compression stockings on lower limb volume serial variations in standardized flights

Background

Graduated compression stocking (GCS) use during flights demonstrated to positively impact leg oedema. Nevertheless, these data were collected in a single flight, mainly at the ankle, and using greater than 20 mmHg GCS. This investigation reports data from 16 flights in which the same passenger’s leg circumferences variation were assessed wearing non-graduated ankle-sock or a below-knee 15–20 mmHg GCS.

Methods

The limb was divided by the circumferences in eight sectors, every 4 cm, labelled from 1 to 8, starting from the ankle up. The assessment was done at the take-off and after a 4-h flight time, for a total of 16 flights. The subject used non-graduated ankle socks (elastic band at 4 cm from B-point) during the outgoing flight and below-knee GCS (15–20 mmHg) during the return flight. Interface pressure was assessed at the ankle point of minimum girth (B) and ascending proximally every 4 cm (B+cm) for the GCS, and at B and at the elastic band level (B + 4 cm) for the sock.

Results

GCS interface pressure was 13.3 ± 2.5 mmHg in B and 18.1 ± 2.4 mmHg in B + 4 cm. The sock interface pressure was 3.1 ± 0.7 mmHg in B and 8.1 ± 0.9 mmHg at the band level (B + 4 cm). Socks led to a significant total volume increase (117.3 ± 25.8 mL; 5.2% ±1.1%; P < 0.0001). GCS led to a non-significant total volume decrease (–3.1 ± 14.4 mL; –0.1 ± 0.6%; P = 0.3964) and did not allow for volume increase. The different sectors showed a heterogeneous volume variation, not following a precisely graduated or progressive compression profile.

Conclusions

Leg oedema following a 4-h flight is controlled by <20 mmHg GCS. Leg fluids, with and without GCS, are mobilized in a non-graduated profile from the ankle to the knee after prolonged sitting on a plane.

Asymptomatic portal vein aneurysms: To treat, or not to treat?

Background Portal vein aneurysms are rare dilations in the portal venous system, for which the etiology and pathophysiological consequences are poorly understood. Method We reviewed the existing literature as well as present a unique anecdotal case of a patient presenting with a very large portal vein aneurysm that was successfully managed conservatively and non-operatively without anticoagulation, with close follow-up and routine surveillance. Result The rising prevalence of abdominal imaging in clinical practice has increased rates of portal vein aneurysm detection. While asymptomatic aneurysms less than 3 cm can be clinically observed, surgical intervention may be necessary in large asymptomatic aneurysms (>3 cm) with or without thrombus, or small aneurysms with evidence of evolving mural thrombus formation on imaging. Conclusion Portal vein aneurysms present a diagnostic challenge for any surgeon, and the goal for surgical therapy is based on repairing the portal vein aneurysm, and if portal hypertension is present decompressing via surgically constructed shunts.

Recommendations for the medical management of chronic venous disease: The role of Micronized Purified Flavanoid Fraction (MPFF)

Scope A systematic review of the clinical literature concerning medical management of chronic venous disease with the venoactive therapy Micronized Purified Flavonoid Fraction was conducted in addition to an investigation of the hemodynamics and mechanism of chronic venous disease. Methods The systematic review of the literature focused on the use of Micronized Purified Flavonoid Fraction (diosmin) which has recently become available in the US, in the management of chronic venous disease. The primary goal was to assess the level of evidence of the role of Micronized Purified Flavonoid Fraction in the healing of ulcers, and secondarily on the improvement of the symptoms of chronic venous disease such as edema. An initial search of Medline, Cochrane Database for Systematic Reviews and Google Scholar databases was conducted. The references of articles obtained in the primary search, including a Cochrane review of phlebotonics for venous insufficiency, were reviewed for additional studies. Studies were included if patients had a diagnosis of chronic venous disease documented with Doppler and Impedance Plethysmography. Studies excluded were those that had patients with arterial insufficiency (Ankle Brachial Index < .6), comorbidity of diabetes, obesity, rheumatological diseases, or if other causes of edema were present (congestive heart failure, renal, hepatic or lymphatic cause), or if the patient population had recent surgery or deep vein thrombosis, or had been using diuretics (in studies of edema). Other elements of the study design were to note specifically the type of compression therapy used in conjunction with Micronized Purified Flavonoid Fraction. Results The literature review yielded 250 abstracts, 65 of which met criteria for further review and 10 papers were selected for consideration in the systematic review. Conclusion In summary, the general level of evidence supports the recommendation that the use of medical therapy with Micronized Purified Flavonoid Fraction has beneficial outcomes without serious adverse events. In the United States, diosmiplex is the only available prescription formulation of Micronized Purified Flavonoid Fraction. It is derived from the rinds of oranges and is categorized as a medical food and not as a drug; and may be a particularly attractive therapy for many chronic venous disease patients because of its favorable safety profile. The Working Group for chronic venous disease concurs with previous guidance by the International European Society for Vascular Surgery in 2015 which recommended the use of Micronized Purified Flavonoid Fraction for the healing of venous ulcers, alone and adjunctive to compression therapy, and for the reduction in symptoms of chronic venous disease such as edema.

Matrix Metalloproteinases in Remodeling of Lower Extremity Veins and Chronic Venous Disease

The veins of the lower extremity are equipped with efficient wall, contractile vascular smooth muscle (VSM), and competent valves in order to withstand the high venous hydrostatic pressure in the lower limb and allow unidirectional movement of deoxygenated blood toward the heart. The vein wall structure and function are in part regulated by matrix metalloproteinases (MMPs). MMPs are zinc-dependent endopeptidases that are secreted as inactive pro-MMPs by different cells in the venous wall including fibroblasts, VSM, and leukocytes. Pro-MMPs are activated by other MMPs, proteinases, and other endogenous and exogenous activators. MMPs degrade various extracellular matrix (ECM) proteins including collagen and elastin, and could affect other cellular processes including endothelium-mediated dilation, VSM cell migration, and proliferation as well as modulation of Ca²⁺ signaling and contraction in VSM. It is thought that increased lower limb venous hydrostatic pressure increases hypoxia-inducible factors and other MMP inducers such as extracellular matrix metalloproteinase inducer, leading to increased MMP expression/activity, ECM protein degradation, vein wall relaxation, and venous dilation. Vein wall inflammation and leukocyte infiltration cause additional increases in MMPs, and further vein wall dilation and valve degradation, that could lead to chronic venous disease and varicose veins (VVs). VVs are often presented as vein wall dilation and tortuosity, incompetent venous valves, and venous reflux. Different regions of VVs show different MMP levels and ECM proteins with atrophic regions showing high MMP levels/activity and little ECM compared to hypertrophic regions with little or inactive MMPs and abundant ECM. Treatment of VVs includes compression stockings, venotonics, sclerotherapy, or surgical removal. However, these approaches do not treat the cause of VVs, and other lines of treatment may be needed. Modulation of endogenous tissue inhibitors of metalloproteinases (TIMPs), and exogenous synthetic MMP inhibitors may provide new approaches in the management of VVs.

Rupture of a True Profunda Femoris Artery Aneurysm: Two Case Reports and Review of the English Language Literature

Profunda femoris artery aneurysms (PFAAs) are very rare and easily overlooked because they are located deeply within thigh muscle. PFAAs have a high rate of rupture in comparison with other peripheral arterial aneurysms, resulting in emergency surgical procedures with significant morbidity. PFAA is diagnosed with color arterial Doppler ultrasound, although computed tomography angiography remains the best imaging method to precisely define the exact site and length of arterial involvement. PFAAs should be treated surgically once diagnosed, even if they are asymptomatic due to the high incidence of complications. Currently, around 28 patients with PFAA rupture, including the 2 cases from this report, have been described in the English language literature. In this report, we describe the diagnosis and treatment of 2 true ruptured aneurysms of the profunda femoris artery with 2 different approaches, and will review the relevant literature.

Vertebral artery dissection following intravascular catheter placement: a case report and review of the literature

Vertebral artery dissections (VAD) are known to occur as a result of mechanical manipulations of the cervical region, traumatic injury, iatrogenic injury and are also known to arise spontaneously. We report a case of vertebral artery dissection following vertebral artery cannulation during a central line placement and review the literature. The patient underwent intravascular catheter placement that subsequently demonstrated arterial blood. Duplex ultrasound and computed tomographic (CT) scan confirmed vertebral artery cannulation. The catheter was removed at the bedside with pressure, and a subsequent duplex ultrasound scan revealed a vertebral artery dissection. There were no neurological sequelae. The patient was successfully anticoagulated with warfarin but died from unrelated complications. This case report describes the rare iatrogenic event of VAD and reviews its etiology, diagnosis, complications, and management.

Noninfectious Saccular Abdominal Aortic Aneurysm

Saccular aortic aneurysms are eccentrically shaped and are commonly thought to be the consequence of infection of the aorta. However, saccular-type aneurysms can be found independent of any clinical or subclinical infection and can be associated with a penetrating aortic ulcer. Moreover, penetrating aortic ulcers have been described in the thoracic aorta, but there is a paucity of any documentation of this clinical and pathologic entity occurring in the abdominal aorta. The authors describe 2 cases of symptomatic, penetrating atherosclerotic ulcers of the abdominal aorta causing saccular, noninfectious abdominal aortic aneurysms.

Prolonged Mechanical Circumferential Stretch Induces Metabolic Changes in Rat Inferior Vena Cava

OBJECTIVE/BACKGROUND

Circumferential stretch on the vein wall has been suggested as a potential etiological factor in the development of varicose veins. However, the influence of vein wall stretch on vein metabolism has not yet been explored. The aim of this study was to investigate the effect of short and prolonged mechanical stretch on vein wall metabolism.

METHODS

Circular segments of inferior vena cava from male Sprague-Dawley rats were exposed to normal 0.5-g (nonstretched) or high 2-g (stretched) tension for short (4 h) or prolonged (18 h) duration (five vein segments per group). Contraction response to phenylephrine (10^-5 M) and KCl (96 mM) was elicited to observe the effect of circumferential stretch on vein function. The polar and organic metabolites in vein tissue were extracted using a bilayer extraction method. Aqueous and organic extracts were analyzed using nuclear magnetic resonance spectroscopy and ultra performance liquid chromatography coupled to mass spectrometry, respectively. Data acquired from both analytical platforms were analyzed using mathematical modeling.

RESULTS

Increased concentrations of valine (p = .02) and choline (p = .03) metabolites and triglyceride moieties (p = .03) were observed in veins stretched for 18 h compared with the nonstretched/18 h group.

DISCUSSION

Increased concentrations of branched chain amino acid valine and cell membrane constituent choline indicate increased muscle breakdown and increased metabolism of membrane phospholipids under stretch in an ex-vivo model. Increased intensities of triglyceride moieties in stretched vein segments for 18 h suggest that high pressure may induce an inflammatory response.

CONCLUSION

This study has shown that prolonged mechanical circumferential stretch (18 h) alters the metabolic profile of rat inferior vena cava.

Mitogen-Activated Protein Kinase Pathway Regulates Cell Proliferation in Venous Ulcer Fibroblasts

Venous ulcer fibroblasts have been demonstrated to have low growth rates in response to platelet-derived growth factor (PDGF). Mitogen-activated protein kinase (MAPK) is an important signal transduction mechanism that regulates growth, differentiation, and apoptosis in eukaryotic cells. PDGF binds PDGF receptors that activate a multitiered signaling cascade involving MAPK. We hypothesize that the growth regulation in venous ulcer fibroblasts is dependent on the MAPK extracellular signal-regulated kinase (ERK) pathway in the presence of PDGF. Fibroblasts (fb) were isolated from 8 patients with venous ulcers (w-fb) and the normal skin (n-fb) of the ipsilateral thigh via punch biopsies. Fb were plated at 1,500 cells/dish and treated with PDGF-AB (10 ng/mL) for 15 days. Growth rates were determined. Immunoblot analysis of MAPK ERK for n-fb and w-fb were analyzed. To determine if PDGF-stimulated w-fb and n-fb utilized the MAPK ERK pathway in a dependent manner, the upstream kinase MAPK kinase 1 (MEK 1) was inhibited by PD 98059. In addition, fb were treated with chronic venous ulcer wound fluid (WF) to study its effect on MAPK ERK. In the presence of PDGF, growth rates were substantially lower in w-fb than in n-fb, and MAPK was activated in 6/8 w-fb and in only 2/8 n-fb. Fibroblasts expressing MAPK had significantly reduced cell proliferation compared to fibroblasts not expressing MAPK (p = 0.023). PD 98059 significantly inhibited wfb and n-fb cell proliferation from basal level, which was reversible with addition of PDGF. In neonatal fibroblasts WF demonstrated inhibition of MAPK ERK over time and addition of PD98059 was not additive. This study suggests that the MAPK ERK pathway is important for cell proliferation in venous ulcer fibroblasts. In the presence of PDGF, fibroblasts with decreased growth rate express MAPK, and proliferation is further abrogated with addition of MEK 1 inhibitor, suggesting the importance of the MAPK ERK pathway regulating w-fb and nfb proliferation. Although the majority of w-fb activated the MAPK ERK pathway in the presence of PDGF, proliferation was significantly attenuated, indicating that other MAPK inhibitory pathways are competing. Venous ulcer wound fluid directly inhibits the MAPK ERK pathway, suggesting that the venous ulcer wound environment has negative trophic factors that effect fibroblasts proliferation and ulcer healing.

Chronic venous disease - Part II: Proteolytic biomarkers in wound healing

Venous leg ulcers (VLU) are characterized by sustained proteolytic microenvironment impairing the healing process. Wound fluid (WF) reflect the biomolecular activities occurring within the wound area; however, it is unclear if WF from different healing phases have different proteolytic profiles and how VLU microenvironment affects the wound healing mechanisms. We investigated the proteolytic network of WF from distinct VLU phases, and in WF- and LPS-stimulated THP-1 monocytes treated with glycosaminoglycan sulodexide, a well known therapeutic approach for VLU healing. WF were collected from patients with VLU during inflammatory (Infl) and granulating (Gran) phases. WF and THP-1 supernatants were analyzed for nine matrix metalloproteinases (MMP) and four tissue inhibitors of metalloproteinases (TIMP) by multiplex immunoassays. Our results demonstrated that: 1) WF from Infl VLU contained significantly increased concentrations of MMP-2, MMP-9, MMP-12, TIMP-1, and TIMP-2 compared to Gran WF; 2) WF from Gran VLU showed significantly increased levels of MMP-1, MMP-7, MMP-13, and TIMP-4 compared to Infl WF; 3) LPS- and WF-stimulation of THP-1 cells significantly increased the expression of several MMP compared to untreated cells; 4) Sulodexide treatment of both LPS- and WF-stimulated THP-1 significantly down-regulated the release of several MMPs. Our study provides evidence-based medicine during treatment of patients with VLU. WF from Infl and Gran VLU have different MMP and TIMP signatures, consistent with their clinical state. The modulation of proteolytic pathways in wound microenvironment by glycosaminoglycan sulodexide, provide insights for translating research into clinical practice during VLU therapy.

Pathophysiology of wound healing and alterations in venous leg ulcers-review

Venous leg ulcer (VLU) is one of the most common lower extremity ulcerated wound, and is a significant healthcare problem with implications that affect social, economic, and the well-being of a patient. VLU can have debilitating related problems which require weekly medical care and may take months to years to heal. The pathophysiology of VLU is complex, and healing is delayed in many patients due to a persistent inflammatory condition. Patient genetic and environmental factors predispose individuals to chronic venous diseases including VLU. Changes in shear stress affecting the glycocalyx are likely initiating events, leading to activation of adhesion molecules on endothelial cells, and leukocyte activation with attachment and migration into vein wall, microcirculation, and in the interstitial space. Multiple chemokines, cytokines, growth factors, proteases and matrix metalloproteinases are produced. The pathology of VLU involves an imbalance of inflammation, inflammatory modulators, oxidative stress, and proteinase activity. Understanding the cellular and biochemical events that lead to the progression of VLU is critical. With further understanding of inflammatory pathways and potential mechanisms, certain biomarkers could be revealed and studied as both involvement in the pathophysiology of VLU but also as therapeutic targets for VLU healing.

Impact of coexisting aneurysms on open revascularization for aortoiliac occlusive disease

OBJECTIVE

National data evaluating outcomes for occlusive abdominal aortic reconstructions are well described. The relative effect of operative indication as well as the presence of concomitant abdominal aortic aneurysm (AAA) on in-hospital mortality is not well defined.

METHODS

The Nationwide Inpatient Sample was queried to identify patients who underwent open aortic surgery (2003-2010). Indication for surgery was classified by International Classification of Diseases, Ninth Revision diagnostic codes to identify isolated occlusive indications as well as combined occlusive disease and AAA. Primary outcome was in-hospital mortality. Secondary outcomes were complications and discharge disposition.

RESULTS

Overall, 56,374 underwent aortic reconstruction, 48,591 for occlusive disease (86.2%) and 7783 for combined occlusive disease with AAA (13.8%). Intermittent claudication was the most common indication for intervention (60.9%), whereas 39.7% underwent intervention for critical limb ischemia (22.2% rest pain, 17.6% gangrene). Patients with intermittent claudication had more concomitant AAAs (17.3%) than did patients with critical limb ischemia (8.4%). The baseline characteristics for those with occlusive disease and combined occlusive with AAA disease were similar in terms of obesity (4.8% vs 4.2%; P = .27) and congestive heart failure (6.6% vs 6.3%; P = .65) but differed by age (62.2 years vs 68.4 years; P < .0001) and hypertension (65.4% vs 69.1%; P = .005). Patients with combined occlusive and AAA disease had higher mortality than those with occlusive disease alone (3.9% vs 2.7%; P = .01). On multivariable regression, factors associated with in-hospital mortality included gangrene with AAA compared with gangrene alone (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.6-4.7; P < .0002), age >65 years age (OR, 3.1; 95% CI, 2.4-4.1; P < .0001), renal failure (OR, 2.7; 95% CI, 1.9-3.8; P < .0001), and concurrent lower extremity revascularization (OR, 1.3; 95% CI, 1.1-1.7; P < .02).

CONCLUSIONS

Intermittent claudication or critical limb ischemia with concomitant AAA carries a higher mortality than intermittent claudication or critical limb ischemia alone, especially in older patients with gangrene requiring revascularization and renal insufficiency. Preoperative risk stratification strategies should focus on the indication for surgery as well as the presence of concomitant AAA.

Practice patterns of adjunctive therapy for venous leg ulcers

Objectives Venous leg ulcers (VLU) are the most severe clinical sequelae of venous reflux and post thrombotic syndrome. There is a consensus that ablation of refluxing vein segments and treatment of significant venous obstruction can heal VLUs. However, there is wide disparity in the use and choice of adjunctive therapies for VLUs. The purpose of this study was to assess these practice patterns among members of the American Venous Forum. Methods The AVF Research Committee conducted an online survey of its own members, which consisted of 16 questions designed to determine the specialty of physicians, location of treatment, treatment practices and reimbursement for treatment of VLUs Results The survey was distributed to 667 practitioners and a response rate of 18.6% was achieved. A majority of respondents (49.5%) were vascular specialists and the remaining were podiatrists, dermatologists, primary care doctors and others. It was found that 85.5% were from within the USA, while physicians from 14 other countries also responded. Most of the physicians (45%) provided adjunctive therapy at a private office setting and 58% treated less than 5 VLU patients per week. All respondents used some form of compression therapy as the primary mode of treatment for VLU. Multilayer compression therapy was the most common form of adjunctive therapy used (58.8%) and over 90% of physicians started additional modalities (biologics, negative pressure, hyperbaric oxygen and others) when VLUs failed compression therapy, with a majority (65%) waiting less than three months to start them. Medicare was the most common source of reimbursement (52.4%). Conclusions Physicians from multiple specialties treat VLU. While most physicians use compression therapy, there is wide variation in the selection and point of initiation for additional therapies once compression fails. There is a need for high-quality data to help establish guidelines for adjunctive treatment of VLUs and to disseminate them to physicians across multiple specialties to ensure standardized high-quality treatment of patients with VLUs.

Venous leg ulceration pathophysiology and evidence based treatment

Venous leg ulceration (VLU) is one of the most predominate medical disorders worldwide and in the western hemisphere it affects around 1.5% of the general population and up to 5% of the elderly population. Unfortunately, this trend will only increase given the growth of an aging population worldwide. Understanding its pathophysiology that begins with venous hemodynamic abnormalities and leads to inflammatory alterations with microcirculatory changes is critical to delivering effective curative therapy. As such, the main component to treatment is reversing the underlying venous hypertension and pro-inflammatory milieu using compression treatment along with various adjuvant therapies. Given its impact, a comprehensive multi-pronged approach to care, treatment and prevention is required to reverse the increasing trend that is observed worldwide.

Glycosaminoglycan sulodexide modulates inflammatory pathways in chronic venous disease

Inflammation represents an important epiphenomenon in the etiopathogenesis of chronic venous disease, a worldwide debilitating condition affecting millions of subjects. The pathophysiology of chronic venous disease (CVD) is based on the hemodynamic abnormalities in conjunction to alterations in cellular and extracellular matrix biocompounds. The endothelial dysfunction results from early perturbation in the endothelium linked to glycocalyx injury and promoted by inflammatory cells and mediators (such as matrix metalloproteinases and interleukins), which lead to progressive dilation of the vein resulting in chronic venous insufficiency. Activated leukocytes during the inflammatory process release enzymes, free radicals, chemokines and inflammatory cytokines in the vessel microenvironment, which are responsible for the changes of the venous wall and venous valve, reflux and venous hypertension, and the development/progression of tissue destruction and skin changes. Sulodexide, a highly purified mixture of glycosaminoglycans composed by 80% fast moving heparin and 20% of dermatan sulphate, exhibits anti-thrombotic and profibrinolytic properties, restoring also the essential endothelial glycocalyx. Glycosaminoglycan sulodexide has been also characterized to reduce the release of inflammatory cytokines/chemokines and to inhibit the matrix metalloproteinases-related proteolytic cascades, counteracting endothelial dysfunctions. The pleiotropic effects of sulodexide set the basis for a very promising agent in treating the spectrum of CVD.

Pathophysiology of chronic venous disease

Chronic venous disease (CVD) is a debilitating condition with a prevalence between 60-70%. The disease pathophysiology is complex and involves genetic susceptibility and environmental factors, with individuals developing visible telengiectasias, reticular veins, and varicose veins. Patient with significant lower extremity symptoms have pain, dermal irritation, swelling, skin changes, and are at risk of developing debilitating venous ulceration. The signature of CVD is an increase in venous pressure referred to as venous hypertension. The various symptoms presenting in CVD and the clinical signs that are observed indicate that there is inflammation, secondary to venous hypertension, and it leads to a number of inflammatory pathways that become activated. The endothelium and glycocalyx via specialized receptors are critical at sensing changes in shear stress, and expression of adhesion molecules allows the activation of leukocytes leading to endothelial attachment, diapedisis, and transmigration into the venous wall/valves resulting in venous wall injury and inflammatory cells in the interstitial tissues. There is a complex of cytokines, chemokines, growth factors, proteases and proteinases, produced by activated leukocytes, that are expressed and unbalanced resulting in an environment of persistent inflammation with the clinical changes that are commonly seen, consisting of varicose veins to more advanced presentations of skin changes and venous ulceration. The structural integrity of protein and the extracellular matrix is altered, enhancing the progressive events of CVD. Work focusing on metabolic changes, miRNA regulation, inflammatory modulation and the glycocalyx will further our knowledge in the pathophysiology of CVD, and provide answers critical to treatment and prevention.

Which dressings reduce inflammation and improve venous leg ulcer healing

Chronic venous leg ulcers (VLU) affect around 1% of the adult population in the Western world. The impact of VLU is both social and economic, with significant expenditures on active venous ulcers to provide medical treatment and eventual healing. At the core of VLU is venous hypertension which affects the venous macrocirculation. The changes incurred in venous hemodynamics leads to microcirculatory changes affecting the postcapillary venule and surrounding tissues. Inflammation by leukocytes affecting the venous endothelium, promotes a complex cascade and activation of adhesion molecules expression, chemokines and cytokines released, altered growth factor responses, and activation of protease (e.g. tPA) and proteinase (e.g. MMPs) activity that causes dysregulation and compromise of tissue integrity with eventual dermal damage and ulcer development. A critical component to treating VLU is correcting the abnormal venous hemodynamics and compression therapy. Unfortunately, VLU recurrence ranges between 30–70%, and other modalities in therapy along with compression are required. The goal for adjuvant products is to restore the balance from an inflammatory chronic wound to that of a reparative wound that will promote provisional matrix and epithelialization. There are many products on the market that can be used as adjuvant to compression therapy, but it must be recognized that there is a paucity of clinical trials that have evaluated the clinical effectiveness of specific products with clearly defined end points, and most importantly a healed VLU with a low recurrence rate. This review will discuss the fundamentals of VLU inflammation, and evaluate the available literature that may have benefit in reducing inflammation and lead to effective VLU healing.

Inflammation in chronic venous ulcers

Chronic venous ulcers (CVUs) occur in approximately 1% of the general population. Risk factors for chronic venous disease (CVD) include heredity, age, female sex and obesity. Although not restricted to the elderly, the prevalence of CVD, especially leg ulcers, increases with age.1 CVD has a considerable impact on health-care resources. It has been estimated that venous ulcers cause the loss of approximately two million working days and incur treatment costs of approximately $3 billion per year in the USA.2 Overall, CVD has been estimated to account for 1–3% of the total health-care budgets in countries with developed health-care systems.1 The pathophysiology of dermal abnormalities in CVU is reflective of a complex interplay that involves sustained venous hypertension, inflammation, changes in microcirculation, cytokine and matrix metalloproteinase (MMP) activation, resulting in altered cellular function and delayed wound healing.3,4