Peripheral arterial disease

Presentation and patterns of reinterventions after revascularization in patients with premature peripheral arterial disease

OBJECTIVE

Premature peripheral arterial disease (PAD) (age ≤50 years) has been shown to negatively impact the outcomes of lower extremity revascularization (LER). Patients with premature PAD have an increased risk of major amputation compared with older patients. The primary goal of this study is to compare the frequency of reinterventions after LER in patients with premature PAD to their older counterparts with common age of presentation (ie, 60-80 years).

METHODS

A retrospective review of consecutive patients undergoing LER for PAD in a single center was performed. Clinical, procedural, and socioeconomic characteristics were compared between patients with premature PAD and the older group. Perioperative and long-term outcomes were captured and compared including mortality, major amputation, reintervention rate and frequency, as well as major adverse limb events.

RESULTS

There were 1274 patients who underwent LER (4.3% premature, 61.8% age 60-80). Patients with premature PAD were more likely to be females of racial minorities. Notably, the mean Distressed Communities Index score was significantly higher in the premature PAD group compared with the older patients. Patients with premature PAD were significantly more likely to have end-stage renal disease but less likely to have hypertension, hyperlipidemia, and coronary artery disease compared with older patients. There was no significant difference in perioperative complications. After a mean follow-up of 5 years, patients with premature PAD were significantly more likely to undergo more frequent reinterventions compared with older patients. Kaplan-Meier curves showed similar overall survival and major adverse limb event-free survival between the two groups.

CONCLUSIONS

Patients with premature PAD are likely to undergo more frequent reinterventions after initial LER and have similar 5-year survival curves compared with patients at least 20 years older. Demographic and socioeconomic differences impacting patients with premature PAD, even in this relatively underpowered institutional experience, are striking and warrant further investigation.

l-thyroxine attenuates extracellular Hsp90α-induced vascular endothelial calcification in diabetes mellitus, as revealed by parallel metabolic profiles

BACKGROUND AND AIMS

Diabetic atherosclerotic vascular disease is characterized by extensive vascular calcification. However, an elevated blood glucose level alone does not explain this pathogenesis. We investigated the metabolic markers underlying diabetic atherosclerosis and whether extracellular Hsp90α (eHsp90α) triggers vascular endothelial calcification in this particular metabolic environment.

METHODS

A parallel human/animal model metabolomics approach was used. We analyzed 40 serum samples collected from 24 patients with atherosclerosis and from the STZ-induced ApoE-/- mouse model. A multivariate statistical analysis of the data was performed, and mouse aortic tissue was collected for the assessment of plaque formation. In vitro, the effects of eHsp90α on endothelial cell calcification were assessed by serum analysis, Western blotting and immunoelectron microscopy.

RESULTS

Diabetic ApoE-/- mice showed more severe plaque lesions and calcification damage. Stearamide, oleamide, l-thyroxine, l-homocitrulline and l-citrulline are biomarkers of diabetic ASVD; l-thyroxine was downregulated in both groups, and the thyroid sensitivity index was correlated with serum Hsp90α concentration. In vitro studies showed that eHsp90α increased Runx2 expression in endothelial cells through the LRP1 receptor. l-thyroxine reduced the increase in Runx2 levels caused by eHsp90α and affected the distribution and expression of LRP1 through hydrogen bonding with glutamine at position 1054 in the extracellular segment of LRP1.

CONCLUSIONS

This study provides a mechanistic link between characteristic serum metabolites and diabetic atherosclerosis and thus offers new insight into the role of extracellular Hsp90α in promoting vascular calcification.

Transcriptomics analysis of long non-coding RNAs in smooth muscle cells from patients with peripheral artery disease and diabetes mellitus

Diabetes mellitus (DM) is a significant risk factor for peripheral arterial disease (PAD), and PAD is an independent predictor of cardiovascular disorders (CVDs). Growing evidence suggests that long non-coding RNAs (lncRNAs) significantly contribute to disease development and underlying complications, particularly affecting smooth muscle cells (SMCs). So far, no study has focused on transcriptome analysis of lncRNAs in PAD patients with and without DM. Tissue samples were obtained from our Vascular Biobank. Due to the sample's heterogeneity, expression analysis of lncRNAs in whole tissue detected only ACTA2-AS1 with a 4.9-fold increase in PAD patients with DM. In contrast, transcriptomics of SMCs revealed 28 lncRNAs significantly differentially expressed between PAD with and without DM (FDR < 0.1). Sixteen lncRNAs were of unknown function, six were described in cancer, one connected with macrophages polarisation, and four were associated with CVDs, mainly with SMC function and phenotypic switch (NEAT1, MIR100HG, HIF1A-AS3, and MRI29B2CHG). The enrichment analysis detected additional lncRNAs H19, CARMN, FTX, and MEG3 linked with DM. Our study revealed several lncRNAs in diabetic PAD patients associated with the physiological function of SMCs. These lncRNAs might serve as potential therapeutic targets to improve the function of SMCs within the diseased tissue and, thus, the clinical outcome.

Effects of sevoflurane and fullerenol C60 on lower limb ischemia-reperfusion injury in streptozocin-induced diabetic mice

BACKGROUND

Ischemia-reperfusion injury (IRI) poses a significant challenge for physicians, necessitating the management of cell damage and the preservation of organ functions. Various surgical procedures, such as vascular surgery on extremities, temporary cross-clamping of the abdominal aorta in aortic surgery, and the use of a tourniquet in extremity surgeries, may induce lower limb IRI. The susceptibility to IRI is heightened in individuals with diabetes. This study aimed to investigate the effects of fullerenol C60 and sevoflurane on mouse muscle tissue in a lower limb IRI model and to assess their potential in preventing complications arising from ischemia-reperfusion in mice with streptozocin-induced diabetes.

METHODS

A total of 36 adult Swiss albino mice were randomly divided into six groups, each consisting of six mice: control group (group C), diabetes group (group D), diabetes-ischemia/reperfusion group (group DIR), diabetes-ischemia/reperfusion-fullerenol C60 group (group DIR-FC60), diabetes-ischemia/reperfusion-sevoflurane group (group DIR-S), and diabetes-ischemia/reperfusion-sevoflurane-fullerenol C60 group (DIR-S-FC60). Streptozocin (55 mg/kg) was intraperitoneally administered to induce diabetes in the relevant groups, with mice displaying blood glucose levels of 250 mg/dL or higher at 72 h were considered diabetic. After 4 weeks, all groups underwent laparotomy under anesthesia. In DIR-FC60 and DIR-S-FC60 groups, fullerenol C60 (100 mg/kg) was intraperitoneally administrated 30 min before the ischemia period. Sevoflurane, delivered in 100% oxygen at a rate of 2.3% and 4 L/min, was administered during the ischemia period in DIR-S and DIR-S-FC60 groups. In the IR groups, a microvascular clamp was placed on the infrarenal abdominal aorta for 120 min during the ischemia period, followed by the removal of the clamp and a 120-min reperfusion period. At the end of the reperfusion, gastrocnemius muscle tissues were removed for histopathological and biochemical parameter examinations.

RESULTS

Histopathological examination revealed a significant reduction in the disorganization and degeneration of muscle cells in the DIR-S-FC60 group compared to the DIR group (p = 0.041). Inflammatory cell infiltration was notably lower in the DIR-S, DIR-FC60, and DIR-S-FC60 groups than in the DIR group (p = 0.031, p = 0.011, and p = 0.013, respectively). The total damage scores in the DIR-FC60 and DIR-S-FC60 groups were significantly lower than in the DIR group (p = 0.018 and p = 0.008, respectively). Furthermore, the levels of malondialdehyde (MDA) in the DIR-S, DIR-FC60, and DIR-S-FC60 groups were significantly lower than in the DIR group (p < 0.001, p < 0.001, and p < 0.001, respectively). Catalase (CAT) enzyme activity in the DIR-S, DIR-FC60, and DIR-S-FC60 groups was higher than in the DIR group (p = 0.001, p = 0.014, and p < 0.001, respectively). Superoxide dismutase (SOD) enzyme activity in the DIR-FC60 and DIR-S-FC60 groups was also higher than in the DIR group (p < 0.001 and p = 0.001, respectively).

CONCLUSION

Our findings indicate that administering fullerenol C60 30 min prior to ischemia in diabetic mice, in combination with sevoflurane, led to a reduction in oxidative stress and the correction of IR-related damage in muscle tissue histopathology. We believe that the administration of fullerenol C60 before IR, coupled with sevoflurane administration during IR, exerts a protective effect in mice.

Duplex ultrasound and pedal acceleration time as tools to evaluate foot perfusion: a literature review

Currently, the standard non-invasive test for diagnosing Peripheral Arterial Disease is the Ankle-Brachial Index. However, this test becomes unfeasible in a certain population. New evidence proposes the pedal acceleration time, an ultrasound index, as an alternative test. An integrative bibliographic review was carried out between June 3, 2022 and January 8, 2023, to investigate this new index as a tool to assess foot perfusion. Papers published in English, Portuguese, or Spanish between 2012 and 2022 were searched on PubMed, Google Scholar, and Scielo, using the keywords "Peripheral Arterial Disease" AND "Acceleration Time" AND (Pedal OR Plantar). Research that didn't assess foot perfusion using the methods of interest or did not present human data and also case series or reports were excluded. Seven out of the sixty-six articles identified in the searches were selected for the review, all of which had notable methodological limitations. Pedal acceleration time seems to be able to diagnose and stratify and may reflect prognosis.

Incoherent optical fluctuation flowmetry for detecting limbs with hemodynamically significant stenoses in patients with type 2 diabetes

INTRODUCTION

The development of new highly accurate, inexpensive and accessible methods for the detection of lower-extremity peripheral artery disease (LE-PAD) in diabetic patients is required. The aim of this study was to evaluate the accuracy of a new incoherent optical fluctuation flowmetry (IOFF) method in detecting legs with hemodynamically significant stenoses compared to ankle brachial index (ABI) and transcutaneous oximetry (TcPO2) in patients with diabetes mellitus (DM).

MATERIALS AND METHODS

Patients were recruited into 2 groups. Group 1 included patients with DM without LE-PAD and/or diabetic foot syndrome; Group 2 included patients with DM and LE-PAD. All patients underwent the following measurements: ultrasound (reference method), ABI, TcPO2, and the new IOFF method.

RESULTS

The new IOFF method showed a sensitivity of 79.5% and a specificity of 89.8% in detecting limbs with hemodynamically significant stenosis (AUC 0.890, CI 0.822-0.957). TcpO2 allows the diagnosis of LE-PAD with 69.2% sensitivity and 86.2% specificity (AUC 0.817, CI 0.723-0.911). Using a standard ABI cut-off of less than 0.9, the sensitivity and specificity for this parameter were 34.5% and 89.7%, respectively. Increasing the diagnostic cut-off of the ABI on the study group to 0.99 improved sensitivity to 84.6% and specificity to 78% (AUC,0.824 CI 0.732-0.915).

CONCLUSIONS

The new IOFF technique has demonstrated high sensitivity and specificity in the detection of LE-PAD in patients with DM. The high accuracy, rapid measurement, and potential availability suggest that the new IOFF method has a high potential for clinical application in the detection of PAD.

Current Medical Therapy and Revascularization in Peripheral Artery Disease of the Lower Limbs: Impacts on Subclinical Chronic Inflammation

Peripheral artery disease (PAD), coronary artery disease (CAD), and cerebrovascular disease (CeVD) are characterized by atherosclerosis and inflammation as their underlying mechanisms. This paper aims to conduct a literature review on pharmacotherapy for PAD, specifically focusing on how different drug classes target pro-inflammatory pathways. The goal is to enhance the choice of therapeutic plans by considering their impact on the chronic subclinical inflammation that is associated with PAD development and progression. We conducted a comprehensive review of currently published original articles, narratives, systematic reviews, and meta-analyses. The aim was to explore the relationship between PAD and inflammation and evaluate the influence of current pharmacological and nonpharmacological interventions on the underlying chronic subclinical inflammation. Our findings indicate that the existing treatments have added anti-inflammatory properties that can potentially delay or prevent PAD progression and improve outcomes, independent of their effects on traditional risk factors. Although inflammation-targeted therapy in PAD shows promising potential, its benefits have not been definitively proven yet. However, it is crucial not to overlook the pleiotropic properties of the currently available treatments, as they may provide valuable insights for therapeutic strategies. Further studies focusing on the anti-inflammatory and immunomodulatory effects of these treatments could enhance our understanding of the mechanisms contributing to the residual risk in PAD and pave the way for the development of novel therapies.

Quantitative hemodynamic assessment of stenotic below-the-knee arteries using spatio-temporal bolus tracking on 4D-CT angiography

BACKGROUND

Peripheral arterial disease (PAD) is a chronic occlusive disease that restricts blood flow in the lower limbs, causing partial or complete blockages of the blood flow. While digital subtraction angiography (DSA) has traditionally been the preferred method for assessing blood flow in the lower limbs, advancements in wide beam Computed Tomography (CT), allowing successive acquisition at high frame rate, might enable hemodynamic measurements.

PURPOSE

To quantify the arterial blood flow in stenotic below-the-knee (BTK) arteries. To this end, we propose a novel method for contrast bolus tracking and assessment of quantitative hemodynamic parameters in stenotic arteries using 4D-CT.

METHODS

Fifty patients with suspected PAD underwent 4D-CT angiography in addition to the clinical run-off computed tomography angiography (CTA). From these dynamic acquisitions, the BTK arteries were segmented and the region of maximum blood flow was extracted. Time attenuation curves (TAC) were estimated using 2D spatio-temporal B-spline regression, enforcing both spatial and temporal smoothness. From these curves, quantitative hemodynamic parameters, describing the shape of the propagating contrast bolus were automatically extracted. We evaluated the robustness of the proposed TAC fitting method with respect to interphase delay and imaging noise and compared it to commonly used approaches. Finally, to illustrate the potential value of 4D-CT, we assessed the correlation between the obtained hemodynamic parameters and the presence of PAD.

RESULTS

280 out of 292 arteries were successfully segmented, with failures mainly due to a delayed contrast arrival. The proposed method led to physiologically plausible hemodynamic parameters and was significantly more robust compared to 1D temporal regression. A significant correlation between the presence of proximal stenoses and several hemodynamic parameters was found.

CONCLUSIONS

The proposed method based on spatio-temporal bolus tracking was shown to lead to stable and physiologically plausible estimation of quantitative hemodynamic parameters, even in the case of stenotic arteries. These parameters may provide valuable information in the evaluation of PAD and contribute to its diagnosis.

Peripheral artery disease: Update on etiology, pathophysiology, diagnosis and treatment

Peripheral artery disease (PAD) is a condition related to atherosclerosis affecting >200 million people worldwide, and it increases cardiovascular morbidity (mainly from myocardial infarction and stroke) and mortality. Indeed, PAD patients are classified as patients at very high cardiovascular risk. The most common manifestation of PAD is intermittent claudication, which is associated with reduced mobility and leg pain. Nevertheless, asymptomatic PAD is the most frequent form of PAD worldwide; therefore, it remains underdiagnosed and undertreated. The major risk factors for PAD are smoking, diabetes mellitus, hyperlipidemia, hypertension, overweight/obesity, age, male sex, and black race. Hence, the first and most relevant approach in PAD treatment is lifestyle management, with measures such as smoking cessation, healthy diet, weight loss, and regular physical exercise. This should also be supported by an optimal pharmacological approach including lipid-lowering drugs, antihypertensive drugs, antidiabetic agents, and antithrombotics.

Combined evaluation of blood flow and tissue perfusion in diabetic feet by intra-arterial dynamic 4DCT imaging

Critical limb ischemia is associated with high mortality and major amputations. Intra-arterial digital subtraction angiography (IADSA) has been the reference standard but has some shortcomings including the two-dimensional projection and the lack of tissue perfusion information. The aim of this exploratory study is to examine four-dimensional computed tomography (4DCT) angiography and perfusion imaging using low-volume intra-arterial contrast injections for an improved anatomic and hemodynamic assessment in patients with foot ulcers. Three patients underwent a low-volume (2 mL) intra-arterial contrast-enhanced 4DCT examination combined with a diagnostic IADSA. An automated assessment of blood flow and tissue perfusion from the 4DCT data was performed. Vascular structures and corresponding blood flows were successfully assessed and correlated well with the IADSA results. Perfusion values of the affected tissue were significantly higher compared to the unaffected tissue. The proposed 4DCT protocol combined with the minimal usage of contrast agent (2 mL) provides superior images compared to IADSA as three phases (arterial, perfusion, and venous) are captured. The obtained parameters could allow for an improved diagnosis of critical limb ischemia as both the proximal vasculature and the extent of the perfusion deficit in the microvasculature can be assessed.Relevance statementIntra-arterial 4DCT allows for assessing three phases (arterial, perfusion and venous) using minimal contrast (2 mL). This method could lead to an improved diagnosis of critical limb ischemia as both proximal vasculature and the extent of the perfusion deficit are assessed.Trial registrationISRCTN, ISRCTN95737449. Registered 14 March 2023-retrospectively registered, https://www.isrctn.com/ISRCTN95737449 Key points• Three phases (arterial, perfusion, and venous) are obtained from 2 mL intra-arterial 4DCT.• The obtained hemodynamic parameters correlated well with the IADSA findings.• 4DCT surpassed IADSA in terms of assessment of venous blood flow and inflammatory hyperperfusion.• The assessment of tissue perfusion could lead to optimizing the revascularization strategy.

D-Dimer Is a Diagnostic Biomarker of Abdominal Aortic Aneurysm in Patients With Peripheral Artery Disease

Background

Etiology and risk factors of peripheral artery disease (PAD) include age, smoking, and hypertension, etc. , which are shared by an abdominal aortic aneurysm (AAA). Concomitance with AAA in patients with PAD is not rare but is easily overlooked in the clinical situation, though management strategies are altered totally. This study aims to investigate diagnostic biomarkers for the prediction of AAA in patients with PAD.

Methods

A total of 684 patients diagnosed with AAA and/or PAD were enrolled and analyzed retrospectively. Each patient with PAD and AAA was gender and age-matched. Demographic data, medical history, and serum laboratory test profiles were obtained. Statistical analysis was performed to determine diagnostic biomarkers of AAA in patients with PAD.

Results

Firstly, 320 patients with PAD-only and 320 patients with AAA-only were compared. Levels of bilirubin and D-Dimer were decreased, while the incidence of diabetes mellitus, levels of fibrinogen, and platelet count were increased significantly in patients with PAD-only compared with those in patients with AAA-only (P &lt; 0.001). Next, 364 patients with PAD (44 patients with AAA) and 364 patients with AAA (44 patients with PAD) were compared. Multivariate logistic regression analysis confirmed the differential distribution of bilirubin, D-dimer, fibrinogen, and platelet count between patients with AAA and patients with PAD (P &lt; 0.05). Receiver operator curves (ROC) showed that the area under the curve (AUC) of total bilirubin, direct bilirubin, D-dimer, fibrinogen, and platelet count was 0.6113, 0.5849, 0.7034, 0.6473, and 0.6785, respectively. Finally, to further validate the predictive efficacy of mentioned markers, a multivariable logistics regression analysis was performed between the PAD only group and the PAD with AAA group. The results suggested increased levels of D-dimer in the PAD with AAA group compared to the PAD only group (OR: 2.630, 95% CI:1.639–4.221; P &lt; 0.001). In particular, the Youden index suggested that the cut-off value of D-dimer for predicting AAA in patients with PAD was 0.675 mg/L with a sensitivity of 76.9% and a specificity of 84.9% (AUC = 0.8673; 95% CI, 0.8106–0.9240, P &lt; 0.001). In all 364 patients with PAD, 41.46% patients were diagnosed AAA when D-dimer is &gt;0.675 mg/L, while only 3.55% patients were diagnosed AAA when D-dimer ≤ 0.675 mg/L.

Conclusions

PAD and AAA exert different clinical and serum profiles; D-dimer (&gt;0.675 mg/L) is a reliable biomarker for the prediction of AAA in patients with PAD.

Nerve branches to the anterior tibial artery: clinical application

INTRODUCTION

Arteries receive vascular branches (VBs) from peripheral nerves. VBs are thought to be involved in arterial constriction. Although the anterior tibial artery (ATA) receives VBs, information on their branching patterns and distribution areas remains limited. The aim of this study was to investigate the anatomical structures of the VBs reaching the ATA.

MATERIALS AND METHODS

Forty cadaver limbs were examined to assess the branching patterns and distribution areas of the VBs reaching the ATA.

RESULTS

The VBs reaching the ATA ramified from the deep fibular nerve (DFN), and the ATA received two or three VBs in each limb. The following mean distances from the head of fibula to the points at which the VBs reached the ATA were measured: all the VBs, 1st VB, 2nd VB and 3rd VB. The measurements were 51.5 ± 23.2 mm, 33.3 ± 3.7 mm, 53.3 ± 18.6 mm, and 72.2 ± 24.5 mm, respectively. In all limbs, the DFN and the ATA converged after the DFN branched into the 1^st VB. The 2^nd VB in 38 of 40 limbs and the 3^rd VB in 20 of 32 limbs were distributed in the ATA proximal to the convergence point of the ATA and the DFN.

CONCLUSIONS

These findings revealed that all VBs reaching the ATA ramified from the DFN in all limbs. The ATA received two or three VBs, and all the 1^st VBs distributed to the ATA proximal to the convergence point. This article is protected by copyright. All rights reserved.

MicroRNAs in peripheral artery disease: potential biomarkers and pathophysiological mechanisms

Peripheral artery disease (PAD) is a disease of atherosclerosis in the lower extremities. PAD carries a massive burden worldwide, while diagnosis and treatment options are often lacking. One of the key points of research in recent years is the involvement of microRNAs (miRNAs), which are short 20-25 nucleotide single-stranded RNAs that can act as negative regulators of post-transcriptional gene expression. Many of these miRNAs have been discovered to be misregulated in PAD patients, suggesting a potential utility as biomarkers for PAD diagnosis. miRNAs have also been shown to play an important role in many different pathophysiological aspects involved in the initiation and progression of the disease including angiogenesis, hypoxia, inflammation, as well as other cellular functions like cell proliferation and migration. The research on miRNAs in PAD has the potential to lead to a whole new class of diagnostic tools and treatments.

Higher Systemic Immune-Inflammation Index is associated with higher likelihood of peripheral arterial disease

PURPOSE

To explore the association between SII (Systemic Immune-Inflammation Index) and PAD (peripheral arterial disease) in American adults.

METHODS

Related data from NHANES (National Health and Nutrition Examination Survey) database (1999-2004) were collected and analyzed. PAD was diagnosed by ankle brachial index assessment. The association between SII and prevalent PAD was assessed using multivariable logistic regression.

RESULTS

A total of 6,576 eligible subjects (including 6117 subjects without PAD and 459 with PAD) were finally enrolled in the study, among which there were 3,187 females and 3,389 males with a mean SII of 585.3± 401.5. The age of the subjects with PAD was larger compared to those without PAD (70.2±11.8 vs. 58.7±12.5), and the incidence of chronic diseases, that's CAD, diabetes and hypertension, was higher in those without PAD (p<0.001). Multivariable logistic regression indicated that a high SII level was an independent risk factor for PAD (OR = 1.51, 95% CI: 1.18- 1.93, p = 0.0012) after adjusting for body mass index, race, sex, age, diabetes mellitus (yes/no), hypertension (yes/no), and cardiovascular disease (yes/no).

CONCLUSION

It is suggested that a higher SII is associated with a higher risk of PAD.

Frequency of recurrence of peripheral artery disease among angioplasty and stenting patients

Background

Peripheral artery disease (PAD) is a cardiovascular disease that is characterized by obstruction of peripheral artery. It is associated with comorbidities, reduced quality of life and mortality. The aim of this study was to determine the frequency of recurrence of PAD among patients who underwent angioplasty or stenting and associated risk factors.

Methods

In this retrospective study, all patients referred to the cardiovascular center of (XXX) with the diagnosis of lower extremity PAD were included. Patients’ demographic information, age, gender, smoking status, history of diabetes, history of hypertension, dyslipidemia, number of vessels, type of stent, recurrence of the disease, and size of the lesion were obtained from the hospital database. Endovascular revascularization therapy was either performed by angioplasty or stenting method. The data were analyzed by SPSS v21.

Results

Of 88 patients included in this study, 12.5% were reported with restenosis. Gender, age, size of the lesion, the status of smoking, history of hypertension, and dyslipidemia were not significantly associated with the recurrence of stenosis, p > 0.05. There was a significant relationship between the vessels involved and the type of revascularization method and the recurrence of the PAD.

Conclusion

Endovascular revascularization technique and type of vessel involved in PAD are significant factors contributing to restenosis in our population of study. However, further studies with a greater sample size are required in this area.

•

Peripheral artery disease is a cardiovascular disease with obstruction of peripheral artery.

•

It is associated with comorbidities, reduced quality of life and even mortality.

•

Endovascular revascularization technique in PAD are significant factor in our study.

•

However, further studies with greater sample size are required in this area.

Single Intraosseous Simvastatin Application Induces Endothelial Progenitor Cell Mobilization and Therapeutic Angiogenesis in a Diabetic Hindlimb Ischemia Rat Model

BACKGROUND

Endothelial progenitor cells have shown the ability to enhance neovascularization. In this study, the authors tested whether intraosseous delivery of simvastatin could mobilize endothelial progenitor cells and enhance recovery in a hindlimb ischemia model.

METHODS

There are eight groups of rats in this study: normal control; type 1 diabetes mellitus control group control without drug intervention; and type 1 diabetes mellitus rats that randomly received intraosseous simvastatin (0, 0.5, or 1 mg) or oral simvastatin administration (0, 20, or 400 mg). All type 1 diabetes mellitus rats had induced hindlimb ischemia. The number of endothelial progenitor cells in peripheral blood, and serum markers, were detected. The recovery of blood flow at 21 days after treatment was used as the main outcome.

RESULTS

The authors demonstrated that endothelial progenitor cell mobilization was increased in the simvastatin 0.5- and 1-mg groups compared with the type 1 diabetes mellitus control and simvastatin 0-mg groups at 1, 2, and 3 weeks. Serum vascular endothelial growth factor levels were significantly increased at 2 weeks in the simvastatin 0.5- and 1-mg groups, in addition to the increase of the blood flow and the gastrocnemius weight at 3 weeks. Similar increase can also been seen in simvastatin 400 mg orally but not in simvastatin 20 mg orally.

CONCLUSION

These findings demonstrate that a single intraosseous administration of simvastatin mobilized endothelial progenitor cells at a dose one-hundredth of the required daily oral dose in rats, and this potent mobilization of endothelial progenitor cells markedly improved diabetic limb ischemia by means of neovascularization.

Endothelial GABBR2 Regulates Post-ischemic Angiogenesis by Inhibiting the Glycolysis Pathway

Purpose: Angiogenesis post-ischemia plays an essential role in preventing ischemic damage to tissue by improving the blood recovery. Determining the regulatory mechanism of ischemic angiogenesis, therefore, could provide effective therapeutics for ischemic injury. Materials and Methods: The RNA sequencing (RNA-seq) database was used to predict the association of gamma-aminobutyric acid type B receptor subunit 2 (GABBR2) with endothelial-specific expression. The role of GABBR2 in angiogenesis was verified in vitro by downregulating GABBR2 in human umbilical vein endothelial cells (HUVECs) with lentiviral vectors. Besides, the in vivo effect of GABBR2 on the blood recovery of an ischemic hindlimb was demonstrated by establishing a hindlimb ischemia model in normal and GABBR2 adenoviral vector-infected mice. Then, the mobilization of endothelial progenitor cells (EPCs) in peripheral blood post-ischemia was determined by flow cytometry. Finally, the XF analyzer and Western blot were used to determine the effect of GABBR2 on endothelial metabolism. Results: The RNA-seq results indicated a strong association between GABBR2 and endothelial revascularization, and the upregulation of GABBR2 was detected in both hypoxia-treated HUVECs and ischemic mouse hindlimb. Hypoxia treatment for 6 h increased the proliferation, migration, and tube formation of HUVECs, which were inhibited by GABBR2 knockdown. Additionally, GABBR2 downregulation significantly decreased the blood flow recovery of mouse ischemic hindlimb. The expressions of the EPC markers CD34⁺ and CD133⁺ significantly decreased in the peripheral blood in hindlimb post-ischemia. Mechanically, glycolysis-dominated metabolism of HUVECs was compromised by GABBR2 knockdown. Evidences of the decreased expressions of HKII, PFKFB3, and PKM1 also supported the compromised glycolysis induced by GABBR2 downregulation. Conclusion: Our study demonstrated that GABBR2 regulated angiogenesis post-ischemia by inhibiting the glycolysis pathway.

Environmental Pollution and Peripheral Artery Disease

Peripheral artery disease (PAD) of the lower limbs represents one of the most important clinical conditions among vascular disease and can negatively impact quality of life of affected patients, representing also an important socioeconomic burden. Several risk factors predispose to PAD and its complications. Nevertheless, the role of pollution in this context has not been fully evaluated and this article explored the most updated information on epidemiology and environmental pollution in order to hypothesize the possible contribution of air pollution in the onset of PAD. Pollution is an important problem for the global community and has harmful effects on human health and cardiovascular system, and, specifically, particulate matter 10 (PM₁₀) was found significantly associated with PAD.

Cardiovascular diseases in people with diabetes mellitus in Spain according to the Primary Care Clinical Database (BDCAP) in 2017

INTRODUCTION AND OBJECTIVES

Atherosclerotic cardiovascular disease and heart failure are the leading cause of morbidity and mortality in patients with diabetes. The objective of this work is to know the prevalence of atherosclerotic cardiovascular diseases and heart failure in people diagnosed with diabetes in Spain during 2017 and compare them with those not diagnosed with diabetes according to age and sex.

METHODS

Data for diagnoses of diabetes mellitus (DM), acute myocardial infarction (AMI), stroke, peripheral artery disease (PAD) or heart failure (HF) for 2017 were obtained from the National Health System's Primary Care Clinical Database (BDCAP).

RESULTS

Comparing people with diabetes and people without diabetes over 35 years of age, the Odds Ratio (OR) for being diagnosed with acute myocardial infarction, stroke, peripheral artery disease or heart failure is about 2 in those over 64 years of age and more than 4 in patients under that age. This OR is superior in females versus males for all diagnoses apart from peripheral artery disease.

CONCLUSIONS

This study shows the high cardiovascular comorbidity of patients with diabetes in Spain, with a greater excess of risk in patients under 65 years of age, more pronounced in women. We should offer more intensive treatment for DM2 in women.

Prevalence of peripheral arterial disease and associated factors in people with type 2 diabetes

Abstract Introduction: The high rate of diabetes mellitus index (DM), along with the increase in cardiovascular compromise that DM favors, and the scarcity of epidemiological data regarding the prevalence of peripheral arterial disease (PAD) in this population, make it important to study risk factors associated with the development of PAD in the population with type 2 diabetes mellitus (DM2). Objective: To estimate the prevalence of PAD together with the associated factors in a sample of patients with DM2, treated in the Family Health Strategies (FHS) program, in the municipality of Pindamonhangaba, SP. Methods: Quantitative research in a cross-sectional study of 38 individuals who were diagnosed with DM2, between 40 and 77 years old, selected by convenience sampling and treated in the family health program in two different districts of the municipality. The method consisted of the evaluation of personal and anthropometric data, anamnesis and physical examination including the ankle-brachial index (ABI). Results: PAD was present in 21.1% (95%CI: 16.9 to 25.8) of the investigated population. Risk factors observed were age range of 51 to 69 years (75%), overweight (50%), systemic arterial hypertension (SAH) (100%), smoking (62.5%) and physical inactivity (87.5%). Conclusion: The prevalence of PAD was more than a fifth of those diagnosed with DM2, and the most prevalent associated risk factors were SAH, physical inactivity, smoking and overweight with and without PAD.

Challenges in recruitment and adherence to a randomized clinical trial in Brazil on the effects of transcutaneous nervous electrical stimulation on individuals with peripheral arterial disease: A feasibility study

OBJECTIVE

Describe the feasibility, barriers during the recruitment and intervention period, recruitment rate (success and efficiency), and the level of participation and adherence in the randomized clinical trial to verify the effects of transcutaneous electrical nerve stimulation (TENS) for the symptoms of intermittent claudication (IC) and its repercussions on functional capacity, cardiorespiratory fitness and cardiovascular autonomic function in individuals with sta II Fontaine classification, residing in Brazil.

DESIGN

Prospective, double-blind, randomized clinical trial.

SETTING

Level secondary.

PARTICIPANTS

A total of 63 participants were screened, of which 12.6% were included. Eight individuals with peripheral arterial disease (PAD) and IC underwent a protocol that lasted 8 weeks.

INTERVENTIONS

The experimental group received 45 minutes TENS 10 Hz, followed by 30 minutes of aerobic exercise, and the control group received a placebo TENS also followed by 30 minutes of exercise. Incremental walking test, gait impairment questionnaire, treadmill test, heart rate variability, and 4-second test were applied, considering adherence, success, and efficiency.

RESULTS

The most efficient recruitment sources were as follows: 1) referral by physician and 2) referral by a physiotherapist. Out of 63 participants, 8 (12.6%) were included in the clinical trial. Participants were excluded due to the following reasons: not meeting the criteria (41 participants (65%)), locomotion (6 participants (9.5%)), transportation (5 participants (7.9%)), work release (1 participant (1.6%)), and interest (2 participants (3.2%)). The overall participation was 99 participants (51.6%) in a total of 192 sessions offered.

CONCLUSION

It was not possible to succeed in recruitment and adherence rates. The results of this clinical trial reinforce that PAD is neglected, and strategies including a multidisciplinary approach with the effective participation of nursing, physiotherapy, medicine, and nutrition professionals, are necessary to optimize care for individuals with PAD need to be strengthened. Brazilian Registry of Clinical Trials (RBR-8RTZFN).

Vitamin D serum levels and peripheral arterial disease among southern Brazilian adults

OBJECTIVE

To investigate the association between low serum vitamin D levels and peripheral arterial disease (PAD).

METHODS

A cross-sectional study with a consecutive sample of 133 individuals from Caxias do Sul, Brasil. We considered PAD patients those with an ankle-brachial index (ABI) ≤ 0.90 or with arterial revascularization. Vitamin D serum level was categorized as sufficient (≥30 ng/mL), insufficient (>20 to 29 ng/mL), and deficient (<20 ng/mL). Prevalence ratios (RP) were calculated through Poisson regression.

RESULTS

The prevalence of PAD was 50.7% (95% CI 42-59). After adjustment for potential PAD risk factors, RP were 1.08 (95% CI 0.66-1.76) for insufficient serum level and 1.57 (95% CI 0.96-2.57) for deficient vitamin D serum level; (p for trend = 0.020).

CONCLUSION

Vitamin D serum levels showed an inverse and significant dose-response relationship with PAD.

Biomarkers of vascular disease in diabetes: the adipose-immune system cross talk

Experimental and clinical studies aimed at investigating the mechanism(s) underlying vascular complications of diabetes indicate that a great number of molecules are involved in the pathogenesis of these complications. Most of these molecules are inflammatory mediators or markers generated by immune or adipose tissue. Some of them, i.e. resistin and sortilin, have been shown to be involved in the cross talk between adipocytes and inflammatory cells. This interaction is an attractive area of research, particularly in type 2 diabetes and obesity. Other proteins, such as adiponectin and visfatin, appear to be more promising as possible vascular markers. In addition, some molecules involved in calcium/phosphorus metabolism, such as klotho and FGF23, have an involvement in the pathogenesis of diabetic vasculopathy, which appears to be dependent on the degree of vascular impairment. Inflammatory markers are a promising tool for treatment decisions while measuring plasma levels of adipokines, sortilin, Klotho and FGF23 in adequately sized longitudinal studies is expected to allow a more precise characterization of diabetic vascular disease and the optimal use of personalized treatment strategies.

VASCULAR-1 and VASCULAR-2 as a New Potential Angiogenesis and Endothelial Dysfunction Markers in Peripheral Arterial Disease

The quotient of concentrations concerning the key proangiogenic factor, that is, the vascular endothelial growth factor (VEGF-A) and the angiogenesis inhibitor, namely, its soluble receptors (sVEGFR-1 or sVEGFR-2), seems to reflect increased hypoxia and intensity of compensation angiogenesis. Therefore, it can be an ischemic and endothelial dysfunction marker reflected in intermittent claudication (IC) or critical limb ischemia (CLI) in patients with symptomatic peripheral arterial disease (PAD). The main objective of this study was to evaluate the levels of VEGF-A/sVEGFR-1 and VEGF-A/sVEGFR-2—presented using a novelty acronym VASCULAR-1 and VASCULAR-2—in patients with IC and CLI, as well as displayed in 4 classes of severity of PAD. VASCULAR-1 and VASCULAR-2 were calculated using the plasma of venous blood sampled from 80 patients with IC (n = 65) and CLI (n = 15) and the control group (n = 30). Patients with CLI were reported to have a slightly higher index of VASCULAR-1 and double VASCULAR-2 levels as compared to patients with IC (P = nonsignificant), and these markers were significantly higher than controls (P < .01 and P < .01, respectively). VASCULAR-2 levels were observed to have an increasing tendency in the subsequent degrees of PAD severity according to the Fontaine classification (P = .02). In view of the need to consider the role of the proangiogenic and antiangiogenic factor in the assessment of the so-called “angiogenic potential,” VASCULAR-1 ratio and VASCULAR-2 ratio may be a new useful biomarker of limb ischemia in patients with IC and CLI. However, this requires further studies and evidence on a very large group of patients with PAD.

An Overview of Peripheral Artery Disease in the Elderly: A Study in a Tertiary Hospital Southern Nigeria

BACKGROUND

The incidence of Peripheral Artery Disease (PAD), one of the manifestations of atherosclerosis, is increasing worldwide with significant effects on the quality of life. The disease is a strong prognostic marker for future cardiovascular events in people over 60 years, but relatively little is known about the condition among the elderly in sub-Saharan Africa.

OBJECTIVE

The objective of this study was to determine the prevalence and pattern of peripheral artery disease in elderly patients. Materials and Methods: A cross-sectional hospital-based study was carried out among elderly patients aged 60 years and above attending the Geriatric Clinic of the Department of Family Medicine of University of Benin Teaching Hospital, Edo State, Nigeria, from September to November 2017. Using systematic random sampling technique, 370 respondents were recruited from a sampling frame of 2160 respondents and a sampling fraction of 6. A structured questionnaire was administered to collect data on sociodemographic characteristics, lifestyle variable, and medical history. The ankle-brachial index (ABI) and toe-brachial index (TBI) were used to assess for PAD. The analysis was done using descriptive statistics.

RESULTS

The mean age was 69.3 ± 7 years comprising 76.5% females, 50% of the respondents were married, while 47% were widowed. The ABI showed 35.4% prevalence of PAD, while TBI for respondents with elevated ABI was 45.0%.

CONCLUSION

The study showed a point prevalence of PAD to be 37.8%. From the total respondents, 45.7% had mild, while 2.9% had severe PAD. Routine screening for PAD is recommended for the early detection and management.

Use and 1-year outcomes with conventional and drug-coated balloon angioplasty in patients with lower extremity peripheral artery disease

BACKGROUND

With the growing use of drug-coated balloons for the treatment of peripheral artery disease, information regarding the safety and effectiveness of drug-coated balloons in current practice is needed. We examined patient, physician, and procedural characteristics as well as cardiovascular and limb events in patients who underwent peripheral vascular intervention with drug-coated balloons.

METHODS

This is a retrospective cohort analysis utilizing Medicare data for 100% of fee-for-service beneficiaries from 2015 to 2016 who had a claim for femoropopliteal intervention. The use of drug-coated balloons was identified via specific transitional pass-through codes. All-cause mortality, all-cause hospitalization, repeat femoropopliteal intervention, and major lower extremity amputation at 1 year were the clinical outcomes of interest.

RESULTS

In total, 83,225 patients underwent femoropopliteal intervention, and drug-coated balloons were utilized in 29% of all procedures. Patients treated with drug-coated balloons had a lower cumulative incidence of all-cause hospitalization, all-cause mortality, and major lower extremity amputation, but were more likely to undergo repeat femoropopliteal intervention when compared with patients treated with conventional balloon angioplasty. After adjustment for measured confounders, patients treated with drug-coated balloons had lower rates of hospitalization (HR 0.91 (0.88, 0.93), P < .001), all-cause mortality (HR 0.89 [0.84, 0.94], P < .001), and major amputation (HR 0.93 [0.88, 0.99], P = .017).

CONCLUSIONS

Patients who underwent femoropopliteal intervention with drug-coated balloons had lower observed rates of all-cause mortality, all-cause hospitalization, and major amputation at 1 year. Interestingly, there was not a reduction in rates of repeat revascularization, and further work is required to understand this finding. Nevertheless, the use of drug-coated balloons appears to be safe in this large study of contemporary patients in the United States.

Anxiety and depression in patients with peripheral arterial disease admitted to a tertiary hospital

Background

Anxiety and depression are highly prevalent neuropsychiatric conditions and are associated with chronic diseases, pain, loss of autonomy, dependence on others to perform routine activities, and loneliness. Depression often has a cause-and-effect relationship with other diseases, such as: acute myocardial infarction (AMI), systemic arterial hypertension (SAH), diabetes mellitus (DM) and peripheral arterial disease (PAD).

Objectives

To estimate the frequency of anxiety and depression in patients of both sexes with PAD admitted to a tertiary hospital.

Methods

This is a descriptive, cross-sectional study, with a non-random sample selected consecutively. The Hospital Anxiety and Depression Scale (HADS) was used to assess anxiety and depression, and the ankle-brachial index (ABI) was used to assess PAD.

Results

The prevalence of anxiety in these patients was 24.4%, with associations between anxiety and monthly family income, smoking, and SAH. The prevalence of depression was 27.6%, with associations between depression and the female gender, being married or in a stable relationship, living on a family income of one minimum wage or less, not being an alcoholic, and having hypertension.

Conclusions

There are high prevalence rates of anxiety and depressive disorders among patients with PAD, which are underdiagnosed and, hence, not properly treated.

Evaluation of Risk Factors for Major Amputation in Patients With Diabetes and Peripheral Artery Disease Receiving Antiplatelet Therapy - Post Hoc Analysis of a Prospective Observational Multicenter Cohort Study (SEASON)

BACKGROUND

Guidelines for peripheral arterial disease (PAD) recommend long-term antiplatelet therapy in symptomatic patients to reduce cardiovascular morbidity and mortality risk. Although diabetes is a known risk factor for PAD, PAD has been undertreated in these patients. This study aimed to evaluate risk factors for major amputation in patients with diabetes undergoing antiplatelet therapy for PAD.Methods and Results:This retrospective analysis of a 2-year observational cohort study (1,745 clinics in Japan, September 2009-2013) evaluated predictors of amputation in patients with diabetes undergoing antiplatelet therapy for PAD. Among 4,016 eligible patients, 52 had an amputation during follow-up. Amputation risk (Cox regression analysis) was predicted at baseline by history of lower extremity revascularization/amputation (hazard ratio [HR]: 2.92; 95% confidence interval [CI]: 1.39, 6.14), chronic kidney disease (HR: 4.19; 95% CI: 1.95, 8.97), and comorbid cerebrovascular and heart disease (HR: 3.32; 95% CI: 1.19, 9.30), and was unaffected by choice of oral antiplatelet therapy. In patients with PAD and diabetes, amputation event rate was highest for those with ankle-brachial pressure index (ABI) <0.40 and progressively decreased at higher ABI cut-offs.

CONCLUSIONS

These findings inform real-world understanding of PAD in diabetic patients receiving antiplatelet therapy in Japan, and showed that ABI <0.4 was the strongest risk factor for amputation.

Neurogenic Claudication: a Review of Current Understanding and Treatment Options

PURPOSE OF REVIEW

With an aging population and increased prevalence of the disease, we set out to evaluate the validity of current diagnostic criteria for neurogenic claudication as well as the efficacy of the treatment options for the main cause, lumbar spinal stenosis (LSS).

RECENT FINDINGS

Epidural steroid injections (ESI) were most efficacious when the injectate is a steroid combined with lidocaine or lidocaine only. There are promising results regarding the efficacy of the minimally invasive lumbar decompression (MILD) procedure as well as interspinous process spacers (IPS) compared to surgical alternatives. Spinal cord stimulators are gaining ground as an effective alternative to surgery in patients with lumbar spinal stenosis that is not responsive to conservative measures or epidural injections. We found that there continues to be a lack of consensus on the diagnostic criteria, management, and treatment options for patients with LSS. The Delphi consensus is the most current recommendation to assist clinicians with making the diagnosis. Physical therapy, NSAIDs, gabapentin, and other conservative therapy measures are unproven in providing long-lasting relief. In patients with radicular symptoms, an ESI may be indicated when a combination of lidocaine with steroids is used or using lidocaine alone. In addition, there is not enough high-quality evidence to make a recommendation regarding the use of MILD versus interspinous spacers for neurogenic claudication. There remains a need for high-quality evidence regarding the efficacy of different conservative treatments, interventional procedures, and surgical outcomes in patients with neurogenic claudication in LSS.

Detection of Endothelial Dysfunction Using Skin Temperature Oscillations Analysis During Local Heating in Patients With Peripheral Arterial Disease

OBJECTIVE

The purpose of this study was to examine correlations between laboratory markers of ED and the degree of endothelium-dependent vasodilation using WAST during a local heating test in patients with PAD.

MATERIALS AND METHODS

The study population consisted of 17 healthy subjects and 38 patients with PAD. The ST on the plantar surface of the first toe was measured during the test, and the inverse wavelet transform was applied to reconstruct the ST signals in three frequency bands corresponding to myogenic, neurogenic, and endothelial mechanisms of vascular tone regulation.

RESULTS

In healthy subjects, a local increase in temperature of up to 42°C caused a greater than threefold increase in the amplitudes of foot ST oscillations. Among patients with PAD, the response to the test was much weaker in all frequency ranges. The level of vasodilation dysfunction correlated with the level of artery stenosis in the lower extremities and with laboratory markers of ED (endothelin, homocysteine, and von Willebrand factor).

CONCLUSION

WAST can be considered as a low cost, portable, and easy to use technique for the noninvasive assessment of ED.

Pathophysiology of peripheral arterial disease in diabetes mellitus

Peripheral arterial disease (PAD) increases the risk of lower extremity amputation. It is also an independent predictor of cardiovascular and cerebrovascular ischemic events, affecting both the quality and expectancy of life. Many studies have demonstrated that the prevalence of PAD in patients with diabetes mellitus (DM) is higher than in non-diabetic patients. In diabetic patients, PAD occurs early with rapid progression, and is frequently asymptomatic. Multiple metabolic aberrations in DM, such as advanced glycation end-products, low-density lipoprotein cholesterol, and abnormal oxidative stress, have been shown to worsen PAD. However, the role of DM in PAD is not completely understood. The purpose of the present article is to review and discuss the pathophysiology of PAD in DM.

The relevance of epigenetics to occlusive cerebral and peripheral arterial disease

Athero-thrombosis of the arteries supplying the brain and lower limb are the main causes of stroke and limb loss. New therapies are needed to improve the outcomes of athero-thrombosis. Recent evidence suggests a role for epigenetic changes in the development and progression of ischaemic injury due to atherosclerotic occlusion of peripheral arteries. DNA hypermethylation have been associated with cardiovascular diseases. Histone post-translational modifications have also been implicated in atherosclerosis. Oxidized low-density lipoprotein regulated pro-inflammatory gene expression within endothelial cells is controlled by phosphorylation/acetylation of histone H3 and acetylation of histone H4 for example. There are a number of challenges in translating the growing evidence implicating epigenetics in atherosclerosis to improved therapies for patients. These include the small therapeutic window in conditions such as acute stroke and critical limb ischaemia, since interventions introduced in such patients need to act rapidly and be safe in elderly patients with many co-morbidities. Pre-clinical animal experiments have also reported conflicting effects of some novel epigenetic drugs, which suggest that further in-depth studies are required to better understand their efficacy in resolving ischaemic injury. Effective ways of dealing with these challenges are needed before epigenetic approaches to therapy can be introduced into practice.