Update on the pathophysiology and medical treatment of peripheral artery disease

Comparisons of risk factors and outcomes between abdominal aortic aneurysm and peripheral arterial disease: a case-control study

Background

There is a paucity of data on direct comparison of clinical measures in patients with abdominal aortic aneurysm (AAA) and those with peripheral arterial disease (PAD). Here, we examine the risk factors and outcomes between these 2 conditions.

Methods

Group differences were examined by Fisher's exact tests with Bonferroni correction, postoperative complications (including delirium and pneumonia) and LOS by logistic regression, and mortality by Cox regression, adjusted for age, sex, smoking, co-morbidities and medications.

Results

In total, 160 men and 33 women aged 74.5years (SD = 9.4) were referred for preoperative cardiac assessment for AAA (n = 70) and PAD (n = 123). Vascular surgery was performed in 148 patients (70% of AAA; 80.5% of PAD). Myocardial infarct was more prevalent in AAA, and diabetes more in PAD, whilst atrial fibrillation, stroke, congestive heart failure and hypertension did not differ between groups. Compared to patients with PAD, there were higher proportions of patients with AAA prescribed with cardiovascular medications, and developed post-operative complications in hospital: odds ratio = 7.34 (95% CI, 2.26-23.84, P < .001), and stayed in hospital >1week: odds ratio = 2.60 (95% CI, 1.15-5.85, P = .021). Compared to those with AAA, patients with PAD were at greater risk of death in the entire sample: hazard ratio = 3.34 (95% CI, 1.64-6.79), and in those who underwent vascular surgery: hazard ratio = 4.90 (95% CI, 1.88-12.79). Left ventricular function did not relate to outcomes.

Conclusions

Differences between AAA and PAD in risk profile and management which may have a bearing on higher risk of death associated with PAD. More intensive cardiovascular management may help improve their outcomes.

Muscle tissue oxygenation in individuals with peripheral arterial disease of different walking abilities: An exploratory study

BACKGROUND

Blood flow restriction caused by peripheral arterial disease (PAD) is reflected in reduced walking capacity. The peripheral mechanisms that may affect the walking capacity of individuals with PAD are not yet fully understood. This study aimed to 1) compare tissue oxygenation and muscle metabolism of individuals with PAD with different walking capacities and 2) evaluate which variables have the greatest potential to explain the variability in distance walked between performance levels.

METHODS

The sample composed of adults diagnosed with PAD underwent evaluation of microvascular function in the gastrocnemius muscle through Near-Infrared Spectroscopy (NIRS) at two time points: (1) during the arterial occlusion maneuver; (2) on a treadmill test with constant speed and inclination (3.2 km/h, 10 %). The following NIRS parameters were selected: (1) percentage of peripheral tissue oxygen saturation (StO2); (2) StO2 delta; (3) reoxygenation rate; (4) time to reach lowest StO2; (5) ischemia resistance time; (6) StO2 in reactive hyperemia. Participants were divided into tertiles (T1, T2, and T3) according to the walking distance in the treadmill test. One-way analysis of variance (ANOVA) was used for comparisons between tertiles and multiple linear regression was used for association analyses.

RESULTS

There were no significant differences between tertiles in baseline values or delta StO2. The reoxygenation rate and StO2 in hyperemia of the occlusion maneuver, as well as the time to reach the lowest StO2 and the ischemia resistance time in the treadmill test, were significantly higher in T3 than in T1 and T2 (p < 0.05). Linear regression demonstrated that the ischemia resistance time is the variable that appears to have the greatest influence on the distance walked (adjusted R2 = 0.83).

CONCLUSION

Better walking performance was associated with better dynamic response capacity to ischemia. Factors such as microvascular, endothelial, and muscular dysfunction appear to be decisive in reducing the walking capacity of individuals with PAD.

Identification of potential biomarkers in cardiovascular calcification based on bioinformatics combined with single-cell RNA-seq and multiple machine learning analysis

BACKGROUND

The molecular and genetic mechanisms underlying vascular calcification remain unclear. This study aimed to determine the differences in calcification marker-related gene expression in macrophages.

METHODS

The expression profiling datasets GSE104140 and GSE235995 were analysed to identify differentially expressed genes (DEGs) between fibroatheroma with calcification and diffuse intimal thickening. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, Weighted Gene Co-expression Network Analysis (WGCNA), and Gene Set Enrichment Analysis (GSEA) were performed to assess functional characteristics. Hub genes were identified through a protein-protein interaction (PPI) network and machine learning approaches. Single-cell RNA sequencing data (GSE159677) validated the expression of calcification-related genes in macrophages, while Mendelian randomization analysis explored their potential causal relationship with coronary calcification. Further validation was conducted using enzyme-linked immunosorbent assay (ELISA) on coronary calcification samples and immunohistochemistry in ApoE-/- mice. Intravascular ultrasound was performed to assess coronary calcification severity.

RESULTS AND CONCLUSIONS

Two key biomarkers, ITGAX and MYD88, were identified as diagnostic indicators of cardiovascular calcification. Both biomarkers were significantly upregulated in calcified samples and were strongly associated with immune processes. Single-cell RNA sequencing confirmed their high expression in multiple immune cell types. Additionally, molecular docking analysis revealed that retinoic acid interacted with both biomarkers, suggesting potential therapeutic relevance. Immunohistochemical and ELISA analyses further validated their elevated expression in calcified samples. These findings provide novel insights into the molecular mechanisms of vascular calcification and highlight potential diagnostic and therapeutic targets.

Lipidomic insights on abdominal aortic aneurysm and peripheral arterial disease

Abdominal aortic aneurysm (AAA) and peripheral arterial disease (PAD) are two cardiovascular diseases associated with considerable morbidity, mortality and quality of life impairment. As they are multifactorial diseases, several factors contribute to their pathogenesis, including oxidative stress and lipid peroxidation, and these may have key roles in the development of these pathologies. Alterations of the lipid metabolism and lipid profile have been reported in cardiovascular diseases but to a lesser extent in AAA and PAD. Modifications in the profile of some molecular lipid species, in particular, native phospholipid and triglyceride species were mainly reported for AAA, while alterations in the fatty acid profile were noticed in the case of PAD. Oxidized phospholipids were also reported for AAA. Although AAA and PAD have a common atherosclerotic root, lipidomics demonstrates the existence of distinct lipid. Lipidomic research regarding AAA and PAD is still scarce and should be set in motion to increase the knowledge on the lipid changes that occur in these diseases, contributing not only to the discovery of new biomarkers for diagnosis and prognosis assessment but also to tailor precision medicine in the clinical field.

The Impact of Peripheral Vascular Motion on Acute Drug Retention of Intravascular Devices

PURPOSE

This goal of this study was to determine the impact of vascular motion on acute drug transfer and retention of drug-coated balloons (DCB) or drug-eluting stents (DES).

METHODS

Commercially available paclitaxel DCBs (Lutonix & IN.PACT) and a paclitaxel DES (Zilver) were subjected to physiological flow and vascular motion conditions using a peripheral-simulating benchtop bioreactor system. Each DCB- or DES-treated artery was subjected to three sets of movement parameters including pulsatile flow with no twisting/bending (P1), pulsatile flow with 16.8° twist, 25° bend and 3.2 mm compression (P2), and pulsatile flow with 68° twist, 35° bend, 21 mm compression (P3). After 24 h, the treated segments were removed and paclitaxel concentrations were measured using pharmacokinetic analysis.

RESULTS

In the group of arteries treated with the Lutonix DCB, there was a significant decrease in arterial paclitaxel concentrations between the P1 and both the P2 and P3 moving parameters (P1 = 404 ± 195 ng/mg, P2 = 14.9 ± 9.92 ng/mg, P3 = 19.2 ± 15.4 ng/mg; P1-P2 p = 0.007, P1-P3 p = 0.005). For the IN.PACT DCB group, no differences in the mean arterial paclitaxel concentrations were observed for the various movements (p = 0.55). Lastly, in the Zilver DES group, differences were only measured between the P2 and P3 moving parameters (P2 = 84.8 ± 32.7 ng/mg, P3 = 0.11 ± 0.06 ng/mg; P2-P3 p = 0.01).

CONCLUSION

Acute retention of arterial paclitaxel levels can be adversely impacted by vascular movement in both DES- and DCB- treated arteries.

Biomaterial-based vascularization strategies for enhanced treatment of peripheral arterial disease

Peripheral arterial disease (PAD) poses a global health challenge, particularly in its advanced stages known as critical limb ischemia (CLI). Conventional treatments often fail to achieve satisfactory outcomes. Patients with CLI face high rates of morbidity and mortality, underscoring the urgent need for innovative therapeutic strategies. Recent advancements in biomaterials and biotechnology have positioned biomaterial-based vascularization strategies as promising approaches to improve blood perfusion and ameliorate ischemic conditions in affected tissues. These materials have shown potential to enhance therapeutic outcomes while mitigating toxicity concerns. This work summarizes the current status of PAD and highlights emerging biomaterial-based strategies for its treatment, focusing on functional genes, cells, proteins, and metal ions, as well as their delivery and controlled release systems. Additionally, the limitations associated with these approaches are discussed. This review provides a framework for designing therapeutic biomaterials and offers insights into their potential for clinical translation, contributing to the advancement of PAD treatments.

Developing Trustworthy Artificial Intelligence Models to Predict Vascular Disease Progression: the VASCUL-AID-RETRO Study Protocol

INTRODUCTION

Abdominal aortic aneurysms (AAAs) and peripheral artery disease (PAD) are two vascular diseases with a significant risk of major adverse cardiovascular events and mortality. A challenge in current disease management is the unpredictable disease progression in individual patients. The VASCUL-AID-RETRO study aims to develop trustworthy multimodal predictive artificial intelligence (AI) models for multiple tasks including risk stratification of disease progression and cardiovascular events in patients with AAA and PAD.

METHODS

The VASCUL-AID-RETRO study will collect data from 5000 AAA and 6000 PAD patients across multiple European centers of the VASCUL-AID consortium using electronic health records from 2015 to 2024. This retrospectively-collected data will be enriched with additional data from existing biobanks and registries. Multimodal data, including clinical records, radiological imaging, proteomics, and genomics, will be collected to develop AI models predicting disease progression and cardiovascular risks. This will be done while integrating the international ethics guidelines and legal standards for trustworthy AI, to ensure a socially-responsible data integration and analysis.

PROPOSED ANALYSES

A consensus-based variable list of clinical parameters and core outcome set for both diseases will be developed through meetings with key opinion leaders. Blood, plasma, and tissue samples from existing biobanks will be analyzed for proteomic and genomic variations. AI models will be trained on segmented AAA and PAD artery geometries for estimation of hemodynamic parameters to quantify disease progression. Initially, risk prediction models will be developed for each modality separately, and subsequently, all data will be combined to be used as input to multimodal prediction models. During all processes, data security, data quality, and ethical guidelines and legal standards will be carefully considered. As a next step, the developed models will be further adjusted with prospective data and internally validated in a prospective cohort (VASCUL-AID-PRO study).

CONCLUSION

The VASCUL-AID-RETRO study will utilize advanced AI techniques and integrate clinical, imaging, and multi-omics data to predict AAA and PAD progression and cardiovascular events.

CLINICAL TRIAL REGISTRATION

The VASCUL-AID-RETRO study is registered at www.clinicaltrials.gov under the identification number NCT06206369.

CLINICAL IMPACT

The VASCUL-AID-RETRO study aims to improve clinical practice of vascular surgery by developing artificial intelligence-driven multimodal predictive models for patients with abdominal aortic aneurysms or peripheral artery disease, enhancing personalized medicine. By integrating comprehensive data sets including clinical, imaging, and multi-omics data, these models have the potential to provide accurate risk stratification for disease progression and cardiovascular events. An innovation lies in the extensive European data set in combination with multimodal analyses approaches, which enables the development of advanced models to facilitate better understanding of disease mechanisms and progression. For clinicians, this means that more precise, individualized treatment plans can be established, ultimately aiming to improve patient outcomes.

Editor's Choice - Daily Remote Ischaemic Preconditioning for Intermittent Claudication: A Sham Controlled Randomised Trial

OBJECTIVE

Remote ischaemic preconditioning (RIPC) is a promising non-invasive strategy in which brief episodes of ischaemia and reperfusion can increase skeletal muscle resistance to ischaemia and improve mobility. This study aimed to determine whether 28 consecutive days of RIPC improved intermittent claudication (IC) symptoms compared with sham intervention.

METHODS

This single centre, parallel, randomised, sham controlled, double blind trial was conducted from January 2022 to April 2023 in outpatient settings. Forty two patients with stable IC Fontaine stage IIa or IIb were randomised to RIPC or sham for 28 days. The pre-specified primary outcome was a change in the maximum walking distance (MWD) after 28 days measured with a treadmill test. A > 10% change in MWD was considered clinically significant. Change in intermittent claudication distance (ICD), time to relief from claudication (TRC), and health related quality of life (HRQoL) measured with the VascuQoL-6 questionnaire were the secondary outcomes (ClinicalTrials.gov ID: NCT05084066).

RESULTS

Forty one men (RIPC = 23, sham = 18) aged 64.9 ± 7.4 years were analysed. A change of > 10% in MWD occurred in 14 patients in the RIPC group vs. eight patients in the sham group (relative risk 1.37, 95% confidence interval 0.74 - 2.25; p = .35). Changes in ICD, TRC, and HRQoL between the groups were not statistically significant.

CONCLUSION

In this trial, RIPC did not significantly improve MWD, ICD, or TRC compared with treatment with a sham device.

Association between alcohol consumption and peripheral artery disease: two de novo prospective cohorts and a systematic review with meta-analysis

AIMS

The association between alcohol consumption and risk of peripheral artery disease (PAD) is inconclusive. We conducted this study to examine the association between alcohol consumption and PAD risk in two de novo cohort studies and a meta-analysis of observational studies.

METHODS AND RESULTS

A systematic review was conducted to identify studies on alcohol consumption in relation to PAD risk. We further used data from two cohorts of 70 116 Swedish and 405 406 British adults and performed a meta-analysis of results from previously published studies and current cohort studies. There was a U-shaped association between alcohol consumption and incident PAD risk in the Swedish and British cohorts. The meta-analysis of results of these two cohorts and previously published studies found that compared with non- or never-drinkers, the relative risk of PAD was 0.83 [95% confidence interval (CI) 0.77-0.89], 0.81 (95% CI 0.74-0.90), and 0.94 (95% CI 0.83-1.07) for light, moderate, and high-to-heavy alcohol drinkers, respectively. The nonlinear meta-analysis revealed a possibly U-shaped association between alcohol consumption and PAD risk (P nonlinearity <0.001). The risk of PAD was observed to be the lowest for 2 drinks/week and to be pronounced for ≥10 drinks/week. All these associations persisted in a sensitivity meta-analysis including cohort and other types of observational studies.

CONCLUSION

Alcohol intake ≤2 drinks/week was associated with a reduced risk of PAD, and the risk of PAD became pronounced with intake ≥10 drinkers/week.

Role of C-Reactive Protein as a Predictor of Early Revascularization and Mortality in Advanced Peripheral Arterial Disease

Background: Elevated high-sensitivity C-reactive protein (hsCRP) levels are associated with poor cardiovascular outcomes, particularly in patients with advanced peripheral arterial disease (PAD). This study aimed to assess the impact of hsCRP on clinical characteristics and long-term outcomes in a cohort of PAD patients. Methods: A total of 346 patients with advanced PAD were enrolled and stratified into two groups based on their median hsCRP level (Group 1: <0.32 mg/dL, Group 2: >0.32 mg/dL). The patients were followed for a mean of 102.70 ± 44.13 months. Their clinical characteristics, comorbidities, and long-term cardiovascular events, including myocardial and/or peripheral revascularization, ischemia, and death, were analyzed. This study evaluated two composite endpoints: major adverse cardiovascular events (MACEs) and major adverse peripheral events (MAPEs). MACEs comprised fatal cardiovascular events, cerebral ischemia, cardiac infarction, myocardial revascularization, acute peripheral arterial occlusion, and peripheral reperfusion. MAPEs included carotid reperfusion, acute peripheral arterial occlusion, and lower limb revascularization. Results: The patients in Group 2 had a higher body mass index, waist circumference, and waist-hip ratio compared to those in Group 1 (all p < 0.05). Inflammatory markers, including fibrinogen and the erythrocyte sedimentation rate, were significantly elevated in Group 2 (both p < 0.01). While the overall incidence of peripheral revascularization was similar between groups, these interventions occurred significantly earlier in Group 2 (28.24 ± 38.87 months vs. 67.04 ± 49.97 months, p = 0.004; HR: 2.015, 95% CI: 1.134-3.580, p = 0.017). The MAPEs were comparable in number, but occurred earlier in Group 2 (36.60 ± 37.35 months vs. 66.19 ± 48.18 months, p < 0.01; HR: 1.99, 95% CI: 1.238-3.181, p = 0.004). Similarly, the MACEs had an earlier onset in Group 2 (40.31 ± 38.95 months vs. 55.89 ± 46.33 months, p = 0.04; HR: 1.62, 95% CI: 0.983-1.987, p = 0.062). A total of 169 deaths were recorded during the follow-up. Group 2 exhibited a significantly higher mortality rate (56% vs. 42%, p < 0.01) and an earlier trend in mortality (76.58 ± 43.53 months vs. 84.86 ± 5.18 months), although this difference did not reach statistical significance (p = 0.22). Conclusions: Elevated hsCRP levels (>0.32 mg/dL) are associated with a worse clinical profile and earlier adverse events in patients with advanced PAD. Group 2 experienced significantly earlier peripheral revascularization, MACEs, and MAPEs. The mortality rates were also significantly higher, highlighting the prognostic value of hsCRP in this population.

Clopidogrel combined with rivaroxaban in peripheral artery disease after revascularization

Background

To evaluate the efficacy and safety of clopidogrel-rivaroxaban combination compared to aspirin-rivaroxaban combination in patients with symptomatic peripheral artery disease (PAD).

Methods

Consecutive patients with symptomatic PAD patients were analyzed from January, 2018 to June, 2022 at Nanjing Drum Tower Hospital. Patients were divided into two groups based on the antithrombotic therapy. The primary efficacy outcome was a composite of major adverse cardiovascular events (MACE) and major adverse limb events (MALE), and the primary safety outcome was major bleeding. Patients were followed until the first occurrence of any outcomes or the study end date (30 June 2024).

Results

A total of 695 patients were enrolled into this study. The clopidogrel-rivaroxaban combination significantly reduced the risk of composite outcome (HR: 0.59, 95%CI: 0.41-0.83) without increasing the risk of major bleeding (HR: 0.68, 95%CI: 0.27-1.69). When analyzed separately, clopidogrel-rivaroxaban combination was associated with a reduced risk of MALE (HR: 0.61, 95%CI: 0.41-0.91), although no significant differences were observed in terms of MACE (HR: 0.64, 95%CI: 0.34-1.20) or all bleeding events (HR: 1.00, 95%CI: 0.52-1.93). In the subgroup analysis, there were no significant interactions between the treatment groups and the subgroups of age, diabetes, lesion sites, Rutherford classifications and renal function for composite outcome, MACE and MALE.

Conclusion

The clopidogrel-rivaroxaban combination in PAD patients may offer enhanced cardiovascular protection without increasing the risk of bleeding complications. These findings suggested that clopidogrel could be a superior alternative to aspirin in dual antithrombotic therapy for PAD management.

Cutting-edge progress of intravascular ultrasound in lower-extremity vascular interventions

Lower-extremity vascular disease has a high morbidity rate and often leads to disability and death in its advanced stages. Although angiography-guided endovascular intervention is the primary treatment for peripheral vascular disease, it frequently fails to detect subtle lumen features and falls short of meeting the increasing clinical need for precise management. Intravascular ultrasound (IVUS) merges noninvasive ultrasound imaging with invasive catheterization techniques, providing 360° imaging of the vascular cross-section and delivering accurate information about lesion morphology. IVUS has been crucial in supporting decisionmaking for preoperative assessment, intraoperative monitoring, and postoperative optimization during vascular interventions. This review aims to summarize the latest applications of IVUS in lower-extremity vascular disease, discuss its strengths and limitations, and explore future directions for its use.

Netrin1-Enriched Exosomes From Genetically Modified ADSCs as a Novel Treatment for Diabetic Limb Ischemia

Diabetic limb ischemia (DLI) is a frequent complication of diabetes and the leading cause of non-traumatic amputation. Traditional treatments like stent placement and bypass surgery may not suit all patients. Exosome transplantation has emerged as a promising therapy. Netrin1, a protective cardiovascular factor, has an unclear role in DLI. This study investigates the role of Netrin1 in DLI patients and evaluates the therapeutic potential of exosomes derived from Netrin1-overexpressing adipose-derived stem cells (N-ADSCs). The expression of Netrin1 is significantly decreased in both endothelial cells and serum of DLI patients, highlighting its potential as a biomarker or therapeutic target. In vitro, Netrin1-enriched exosomes (N-Exos) promoted human umbilical vein endothelial cell (HUVEC) proliferation, migration, tube formation, and increased resistance to apoptosis under high glucose conditions. These protective effects are mediated through PI3K/AKT/eNOS and MEK/ERK pathways, and N-Exos further facilitated macrophage polarization from M1 to M2. In vivo, N-Exos demonstrates superior therapeutic effects over ADSC exosomes (Exos), including enhanced angiogenesis, improved collateral artery remodeling, reduced inflammation, and muscle protection. Collectively, these findings identify Netrin1 as a critical factor in DLI and underscore its significance in disease progression and therapeutic strategies. N-Exos offers a promising non-cellular therapeutic approach for the treatment of DLI.

Berbamine Promotes the Repair of Lower Limb Muscle Damage in Chronic Limb-Threatening Ischemia by Inhibiting Local Inflammation and NF-κB Nuclear Translocation

Background/Objectives: Chronic Limb-Threatening Ischemia (CLTI) is a chronic limb ischemic disease caused by vascular lesions, characterized by pain, ulcers, and gangrene, which can be life-threatening in severe cases. The objective of this study is to explore whether Berbamine (BBM) can protect against and repair ischemic muscle tissue in the lower limbs; Methods: Using a mouse hindlimb ischemia (HLI) model, 36 C57BL6 mice were divided into sham, HLI, and HLI+BBM treatment groups. Results: Our findings indicate that BBM can restore motor function and muscle tissue pathology in mice, potentially by inhibiting the nuclear translocation of nuclear factor kappa-B (NF-κB), thereby alleviating tissue inflammation caused by chronic ischemia, reducing muscle cell apoptosis, inhibiting M1 macrophage polarization, and promoting angiogenesis. Conclusions: Our research suggests that BBM has the potential to protect against ischemic damage in lower limb muscle tissue, providing a new approach to the treatment of CLTI.

Counseling Intervention and Cardiovascular Events in People With Peripheral Artery Disease: A Post Hoc Analysis of the BIP Randomized Clinical Trial

Importance

It is unclear whether counseling to promote walking reduces the risk of major adverse cardiovascular events (MACE) in people with peripheral artery disease (PAD).

Objective

To test whether a counseling intervention designed to increase walking reduced the risk of MACE in patients with PAD.

Design, Setting, and Participants

The BIP trial was a randomized clinical trial, with recruitment performed between January 2015 and July 2018 and follow-up concluded in August 2023. Participants with walking impairment due to PAD from vascular departments in the Australian cities of Brisbane, Sydney, and Townsville were randomly allocated 1:1 to the intervention or control group. Data were originally analyzed in March 2024.

Intervention

Four brief counseling sessions aimed to help patients with the challenges of increasing physical activity.

Main Outcomes and Measures

The primary outcome was the between-group difference in risk of MACE, which included myocardial infarction (MI), stroke, and cardiovascular death. The relationship between Intermittent Claudication Questionnaire (ICQ) scores, PAD Quality of Life (PADQOL) scores, and MACE was examined with Cox proportional hazard regression analyses.

Results

A total of 200 participants were included, with 102 allocated to the counseling intervention (51.0%) and 98 to the control group (49.0%).Participants were followed up for a mean (SD) duration of 3.5 (2.6) years. Median (IQR) participant age was 70 (63-76) years, and 56 of 200 participants (28.0%) were female. A total of 31 individuals had a MACE (composed of 19 MIs, 4 strokes, and 8 cardiovascular deaths). Participants allocated to the intervention were significantly less likely to have a MACE than participants in the control group (10 of 102 participants [9.8%] vs 21 of 98 [21.4%]; hazard ratio [HR], 0.43; 95% CI, 0.20-0.91; P = .03). Greater disease-specific quality of life (QOL) scores at 4 months (ICQ: HR per 1-percentage point increase, 0.97; 95% CI, 0.95-0.99; P < .001; PADQOL factor 3 [symptoms and limitations in physical functioning]: HR per 1-unit increase, 0.91; 95% CI, 0.84-0.98; P = .01) and at 12 months (ICQ: HR per 1-percentage point increase, 0.97; 95% CI, 0.95-0.99; P = .003; PADQOL factor 3: HR per 1-unit increase, 0.91; 95% CI, 0.84-0.98; P = .02) were associated with a lower risk of MACE. In analyses adjusted for ICQ or PADQOL factor 3 scores at either 4 or 12 months, allocation to the counseling intervention was no longer significantly associated with a lower risk of MACE.

Conclusions and Relevance

This post hoc exploratory analysis of the BIP randomized clinical trial suggested that the brief counseling intervention designed to increase walking may reduce the risk of MACE, possibly due to improvement in QOL.

Trial Registration

anzctr.org.au Identifier: ACTRN12614000592640.

Toe-brachial index and toe systolic blood pressure for the diagnosis of peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) of the lower limbs is caused by atherosclerotic occlusive disease in which narrowing of arteries reduces blood flow to the lower limbs. PAD is common; it is estimated to affect 236 million individuals worldwide. Advanced age, smoking, hypertension, diabetes and concomitant cardiovascular disease are common factors associated with increased risk of PAD. Complications of PAD can include claudication pain, rest pain, wounds, gangrene, amputation and increased cardiovascular morbidity and mortality. It is therefore clinically important to use diagnostic tests that accurately identify PAD. Accurate and timely detection of PAD allows clinicians to implement appropriate risk management strategies to prevent complications, slow progression or intervene when indicated. Toe-brachial index (TBI) and toe systolic blood pressure (TSBP) are amongst a suite of non-invasive bedside tests used to detect PAD. Both TBI and TSBP are commonly utilised by a variety of clinicians in different settings, therefore a systematic review and meta-analysis of their diagnostic accuracy is warranted and highly relevant to inform clinical practice.

OBJECTIVES

To (1) estimate the accuracy of TSBP and TBI for the diagnosis of PAD in the lower extremities at different cut-off values for test positivity in populations at risk of PAD, and (2) compare the accuracy of TBI and TSBP for the diagnosis of PAD in the lower extremities. Secondary objectives were to investigate several possible sources of heterogeneity in test accuracy, including the following: patient group tested (people with type 1 or type 2 diabetes, people with renal disease and general population), type of equipment used, positivity threshold and type of reference standard.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the MEDLINE, Embase, CINAHL, Web of Science, LILACS, Zetoc and DARE databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 27 February 2024.

SELECTION CRITERIA

We included diagnostic case-control, cross-sectional, prospective and retrospective studies in which all participants had either a TSBP or TBI measurement plus a validated method of vascular diagnostic imaging for PAD. We needed to be able to cross-tabulate (2 x 2 table) results of the index test and the reference standard to include a study. To be included, study populations had to be adults aged 18 years and over. We included studies of symptomatic and asymptomatic participants. Studies had to use TSBP and TBI (also called toe-brachial pressure index (TBPI)), either individually, or in addition to other non-invasive tests as index tests to diagnose PAD in individuals with suspected disease. We included data collected by photoplethysmography, laser Doppler, continuous wave Doppler, sphygmomanometers (both manual and aneroid) and manual or automated digital equipment.

DATA COLLECTION AND ANALYSIS

Two review authors independently completed data extraction using a standardised form. We extracted data to populate 2 x 2 contingency tables when available (true positives, true negatives, false positives, false negatives). Where data were not available to enable statistical analysis, we contacted study authors directly. Two review authors working independently undertook quality assessment using QUADAS-2, with disagreements resolved by a third review author. We incorporated two additional questions into the quality appraisal to aid our understanding of the conduct of studies and make appropriate judgements about risk of bias and applicability.

MAIN RESULTS

Eighteen studies met the inclusion criteria; 13 evaluated TBI only, one evaluated TSBP only and four evaluated both TBI and TSBP. Thirteen of the studies used colour duplex ultrasound (CDU) as a reference standard, two used computed tomography angiography (CTA), one used multi-detector row tomography (MDCT), one used angiography and one used a combination of CDU, CTA and angiography. TBI was investigated in 1927 participants and 2550 limbs. TSBP was investigated in 701 participants, of which 701 limbs had TSBP measured. Studies were generally of low methodological quality, with poor reporting of participant recruitment in regard to consecutive or random sampling, and poor reporting of blinding between index test and reference standard, as well as timing between index test and reference standard. The certainty of evidence according to GRADE for most studies was very low.

AUTHORS' CONCLUSIONS

Whilst a small number of diagnostic test accuracy studies have been completed for TBI and TSBP to identify PAD, the overall methodological quality was low, with most studies providing a very low certainty of evidence. The evidence base to support the use of TBI and TSBP to identify PAD is therefore limited. Whilst both TBI and TSBP are used extensively clinically, the overall diagnostic performance of these tests remains uncertain. Future research using robust methods and clear reporting is warranted to comprehensively determine the diagnostic test accuracy of the TBI and TSBP for identification of PAD with greater certainty. However, conducting such research where some of the reference tests are invasive and only clinically indicated in populations with known PAD is challenging.

Interaction and combined effect of triglyceride-glucose index and hypertension on type 2 diabetes individuals' peripheral arterial disease risk

BACKGROUND

The interaction and combined effect of the triglyceride-glucose (TyG) index, an alternative parameter of insulin resistance, along with hypertension (HT), on the risk of peripheral arterial disease (PAD), a specific type of atherosclerotic cardiovascular disease, in individuals with type 2 diabetes (T2D) seems straightforward. However, specific research on this topic remains scarce.

METHODS

In this cross-sectional study, 2027 adult participants with T2D were devided into four groups based on the mean values of TyG index and various blood pressure parameters along with its category. Binary logistic regression, interaction analysis, combined effect size, and goodness-of-fit of the constructed models were performed.

RESULTS

The TyG index's individual effect and it's combined effect with HT, or higher systolic blood pressure (SBP) or higher mean arterial pressure in patients with T2D correlated with a higher PAD risk respectively (odds ratio [OR], 0.50, [95% confidence interval {CI} 0.28-0.89]; OR, 0.32, [95% CI 0.12-0.90]; OR, 0.35, [95% CI 0.13-0.94]; OR, 0.35, [95% CI 0.12-0.98], respectively). Only an interaction effect exists between the TyG index and SBP (multiplicative interaction{INTM}: 1.02 [1.002, 1.038]). Combining them can significantly improve the accuracy of predicting PAD (area under the receiver operating characteristic curve {AUC}MAX = 0.7, AUCModel3 + TyG index + SBP-AUCModel3 = 0.027). All P values were < 0.05.

CONCLUSION

This study suggested that TyG index and hypertension, as well as their combined and interaction effect were significantly correlated with the risk of PAD in T2D individuals.

Mesenchymal stromal cell therapy (REGENACIP®), a promising treatment option in chronic limb threatening ischemia - a narrative review

Chronic Limb Threatening Ischemia (CLTI) is a challenging clinical problem associated with high morbidity and mortality. Endovascular interventions have been the cornerstone of treatment whenever possible. It is estimated that CLTI represents < 10% of all Peripheral Artery Disease patients, yet 50% of the patients end up either with a major amputation of the lower limbs or die of cardiovascular causes within one year period, especially in those with unsuccessful revascularization or "no-option" CLTI. Cell-based therapeutics, especially bone marrow-derived mesenchymal stromal cells have emerged as a potential, promising, and novel alternate therapeutic modality in the management of CLTI, bolstered with positive results in numerous research, including randomized and nonrandomized trials. REGENACIP® is one such BM-MSC therapy approved by Central Drugs Standard Control Organization in India for the management of "no-option" Atherosclerotic Peripheral Arterial disease / Buerger's disease patients with established critical limb ischemia in Rutherford Grade III-5 or III-6, not eligible for or have failed traditional revascularization treatment, with rest pain and / or ulcers in the affected limb. The current review aims to deliberate upon the various aspects of CLTI and clinical benefits of REGENACIP® therein.

LncRNA H19/miR-107 regulates endothelial progenitor cell pyroptosis and promotes flow recovery of lower extremity ischemia through targeting FADD

BACKGROUND

Peripheral artery disease (PAD) is an ischemic disease with a rising incidence worldwide. The lncRNA H19 (H19) is enriched in endothelial progenitor cells (EPCs), and transplantation of pyroptosis-resistant H19-overexpressed EPCs (oe-H19-EPCs) may promote vasculogenesis and blood flow recovery in PAD, especially with critical limb ischemia (CLI).

METHODS

EPCs isolated from human peripheral blood was characterized using immunofluorescence and flow cytometry. Cell proliferation was determined with CCK8 and EdU assays. Cell migration was assessed by Transwell and wound healing assays. The angiogenic potential was evaluated using tube formation assay. The pyroptosis pathway-related protein in EPCs was detected by western blot. The binding sites of H19 and FADD on miR-107 were analyzed using Luciferase assays. In vivo, oe-H19-EPCs were transplanted into a mouse ischemic limb model, and blood flow was detected by laser Doppler imaging. The transcriptional landscape behind the therapeutic effects of oe-H19-EPCs on ischemic limbs were examined with whole transcriptome sequencing.

RESULTS

Overexpression of H19 in EPCs led to an increase in proliferation, migration, and tube formation abilities. These effects were mediated through pyroptosis pathway, which is regulated by the H19/miR-107/FADD axis. Transplantation of oe-H19-EPCs in a mouse ischemic limb model promoted vasculogenesis and blood flow recovery. Whole transcriptome sequencing indicated significant activation of vasculogenesis pathway in the ischemic limbs following treatment with oe-H19-EPCs.

CONCLUSIONS

Overexpression of H19 increases FADD level by competitively binding to miR-107, leading to enhanced proliferation, migration, vasculogenesis, and inhibition of pyroptosis in EPCs. These effects ultimately promote the recovery of blood flow in CLI.

The Use of Autologous Cell Therapy in Diabetic Patients with Chronic Limb-Threatening Ischemia

Autologous cell therapy (ACT) is primarily used in diabetic patients with chronic limb-threatening ischemia (CLTI) who are not candidates for standard revascularization. According to current research, this therapy has been shown in some studies to be effective in improving ischemia parameters, decreasing the major amputation rate, and in foot ulcer healing. This review critically evaluates the efficacy of ACT in patients with no-option CLTI, discusses the use of mononuclear and mesenchymal stem cells, and compares the route of delivery of ACT. In addition to ACT, we also describe the use of new revascularization strategies, e.g., nanodiscs, microbeads, and epigenetics, that could enhance the therapeutic effect. The main aim is to summarize new findings on subcellular and molecular levels with the clinical aspects of ACT.

Immune and inflammatory insights in atherosclerosis: development of a risk prediction model through single-cell and bulk transcriptomic analyses

Background

Investigation into the immune heterogeneity linked with atherosclerosis remains understudied. This knowledge gap hinders the creation of a robust theoretical framework essential for devising personalized immunotherapies aimed at combating this disease.

Methods

Single-cell RNA sequencing (scRNA-seq) analysis was employed to delineate the immune cell-type landscape within atherosclerotic plaques, followed by assessments of cell-cell interactions and phenotype characteristics using scRNA-seq datasets. Subsequently, pseudotime trajectory analysis was utilized to elucidate the heterogeneity in cell fate and differentiation among macrophages. Through integrated approaches, including single-cell sequencing, Weighted Gene Co-expression Network Analysis (WGCNA), and machine learning techniques, we identified hallmark genes. A risk score model and a corresponding nomogram were developed and validated using these genes, confirmed through Receiver Operating Characteristic (ROC) curve analysis. Additionally, enrichment and immune characteristic analyses were conducted based on the risk score model. The model's applicability was further corroborated by in vitro and in vivo validation of specific genes implicated in atherosclerosis.

Result

This comprehensive scRNA-seq analysis has shed new light on the intricate immune landscape and the role of macrophages in atherosclerotic plaques. The presence of diverse immune cell populations, with a particularly enriched macrophage population, was highlighted by the results. Macrophage heterogeneity was intricately characterized, revealing four distinct subtypes with varying functional attributes that underscore their complex roles in atherosclerotic pathology. Intercellular communication analysis revealed robust macrophage interactions with multiple cell types and detailed pathways differing between proximal adjacent and atherosclerotic core groups. Furthermore, pseudotime trajectories charted the developmental course of macrophage subpopulations, offering insights into their differentiation fates within the plaque microenvironment. The use of machine learning identified potential diagnostic markers, culminating in the identification of RNASE1 and CD14. The risk score model based on these biomarkers exhibited high accuracy in diagnosing atherosclerosis. Immune characteristic analysis validated the risk score model's efficacy in defining patient profiles, distinguishing high-risk individuals with pronounced immune cell activities. Finally, experimental validation affirmed RNASE1's involvement in atherosclerotic progression, suggesting its potential as a therapeutic target.

Conclusion

Our findings have advanced our understanding of atherosclerosis immunopathology and paved the way for novel diagnostic and therapeutic strategies.

MicroRNAs in diabetic macroangiopathy

Diabetic macroangiopathy is a leading cause of diabetes-related mortality worldwide. Both genetic and environmental factors, through a multitude of underlying molecular mechanisms, contribute to the pathogenesis of diabetic macroangiopathy. MicroRNAs (miRNAs), a class of non-coding RNAs known for their functional diversity and expression specificity, are increasingly recognized for their roles in the initiation and progression of diabetes and diabetic macroangiopathy. In this review, we will describe the biogenesis of miRNAs, and summarize their functions in diabetic macroangiopathy, including atherosclerosis, peripheral artery disease, coronary artery disease, and cerebrovascular disease, which are anticipated to provide new insights into future perspectives of miRNAs in basic, translational and clinical research, ultimately advancing the diagnosis, prevention, and treatment of diabetic macroangiopathy.

Vascular Impairment, Muscle Atrophy, and Cognitive Decline: Critical Age-Related Conditions

The triad of vascular impairment, muscle atrophy, and cognitive decline represents critical age-related conditions that significantly impact health. Vascular impairment disrupts blood flow, precipitating the muscle mass reduction seen in sarcopenia and the decline in neuronal function characteristic of neurodegeneration. Our limited understanding of the intricate relationships within this triad hinders accurate diagnosis and effective treatment strategies. This review analyzes the interrelated mechanisms that contribute to these conditions, with a specific focus on oxidative stress, chronic inflammation, and impaired nutrient delivery. The aim is to understand the common pathways involved and to suggest comprehensive therapeutic approaches. Vascular dysfunctions hinder the circulation of blood and the transportation of nutrients, resulting in sarcopenia characterized by muscle atrophy and weakness. Vascular dysfunction and sarcopenia have a negative impact on physical function and quality of life. Neurodegenerative diseases exhibit comparable pathophysiological mechanisms that affect cognitive and motor functions. Preventive and therapeutic approaches encompass lifestyle adjustments, addressing oxidative stress, inflammation, and integrated therapies that focus on improving vascular and muscular well-being. Better understanding of these links can refine therapeutic strategies and yield better patient outcomes. This study emphasizes the complex interplay between vascular dysfunction, muscle degeneration, and cognitive decline, highlighting the necessity for multidisciplinary treatment approaches. Advances in this domain promise improved diagnostic accuracy, more effective therapeutic options, and enhanced preventive measures, all contributing to a higher quality of life for the elderly population.

Management of Pain in People Living With Chronic Limb Threatening Ischemia: Highlights From a Rapid Umbrella Review

Peripheral artery disease is a complex health condition. It is associated with atherosclerotic occlusive lesions in the arteries limiting normal blood flow, mostly involving the lower extremities, leading to chronic limb-threatening ischemia (CLTI). Chronic unrelenting ischemic leg pain can be debilitating and distressing, contributing to poor health-related quality of life. Comprehensive management of pain associated with CLTI requires multimodal approaches that draw on a range of strategies and specialist treatments delivered by an interdisciplinary team across various health care settings. We recognized a significant gap in evidence-based strategies that are accessible, appropriate, acceptable, effective, and safe for the elderly with CLTI-associated pain. We therefore conducted an umbrella review or overview of multiple existing reviews that employ a rigorous and transparent method to comprehensively identify and synthesize relevant literature including systematic, scoping, and narrative reviews. The purpose of this umbrella review was to aggregate and compare various management options to inform best practices and quality indicators for the management of ischemic pain in older patients with peripheral artery disease.

Oxidative stress and vascular dysfunction: Potential therapeutic targets and therapies in peripheral artery disease

Peripheral artery disease (PAD) is the manifestation of atherosclerosis characterized by the accumulation of plaques in the arteries of the lower limbs. Interestingly, growing evidence suggests that the pathology of PAD is multifaceted and encompasses both vascular and skeletal muscle dysfunctions, which contributes to blunted physical capabilities and diminished quality of life. Importantly, it has been suggested that many of these pathological impairments may stem from blunted reduction-oxidation (redox) handling. Of note, in those with PAD, excessive production of reactive oxygen species (ROS) outweighs antioxidant capabilities resulting in oxidative damage, which may have systemic consequences. It has been suggested that antioxidant supplementation may be able to assist in handling ROS. However, the activation of various ROS production sites makes it difficult to determine the efficacy of these antioxidant supplements. Therefore, this review focuses on the common cellular mechanisms that facilitate ROS production and discusses how excessive ROS may impair vascular and skeletal muscle function in PAD. Furthermore, we provide insight for current and potential antioxidant therapies, specifically highlighting activation of the Kelch-like ECH-associated protein 1 (Keap1) - Nuclear Factor Erythroid 2-related factor 2 (Nrf2) pathway as a potential pharmacological therapy to combat ROS accumulation and aid in vascular function, and physical performance in patients with PAD. Altogether, this review provides a better understanding of excessive ROS in the pathophysiology of PAD and enhances our perception of potential therapeutic targets that may improve vascular function, skeletal muscle function, walking capacity, and quality of life in patients with PAD.

Association between dietary fiber intake and peripheral artery disease in hypertensive patients

BACKGROUND

At present, no studies explored whether dietary fiber intake was associated with the risk of peripheral artery disease (PAD) in hypertensive patients. This study assessed the association between dietary fiber intake and PAD in hypertensive patients.

METHODS

This cross-sectional study collected the data of 4628 participants with the measurement of ankle-brachial pressure index in the National Health and Nutrition Examination Surveys database. Univariate logistic regression analysis was applied to identify variables associated with PAD as confounding factors. Univariate and multivariable logistic regression analyses were used to explore the association between dietary fiber intake and PAD in hypertensive patients. Subgroup analysis was stratified by age, cardiovascular disease, dyslipidemia, diabetes, smoking, and physical activity.

RESULTS

After adjusting for confounding factors, decreased risk of PAD was observed in hypertensive patients with dietary fiber intake > 21 g [odds ratio (OR) = 0.67, 95% confidence interval (CI) 0.46-0.99]. Compared with people with dietary fiber intake ≤ 21 g, those with dietary fiber intake > 21 g were associated with decreased risk of PAD in hypertensive patients < 60 years (OR = 0.23, 95%CI 0.08-0.66). In hypertensive patients without dyslipidemia, dietary fiber intake > 21 g were associated with reduced risk of PAD (OR = 0.33, 95%CI 0.12-0.95). Decreased risk of PAD was also found in hypertensive patients without diabetes in dietary fiber intake > 21 g group (OR = 0.50, 95%CI 0.31-0.78). Dietary fiber intake > 21 g was linked with reduced risk of PAD in hypertensive patients in never smoke group (OR = 0.46, 95%CI 0.24-0.86).

CONCLUSION

Higher dietary fiber intake was associated with reduced risk of PAD in hypertensive patients, suggesting the importance of increase the daily dietary quality especially fiber intake in hypertensive people.

Effects of L-Ornithine-L-Aspartate on Angiogenesis and Perfusion in Subacute Hind Limb Ischemia: Preliminary Study

The current treatment options for peripheral arterial disease (PAD) are limited due to a lack of significant high-level evidence to inform clinical decisions and unfavorable outcomes in terms of cost-effectiveness and amputation rates. In order to suggest the use of the commercially available L-Ornithine-L-Aspartate (LOLA) for treating PAD, we induced hind limb ischemia (HLI) by unilaterally ligating the femoral artery in a rat model. The rats were randomly divided into three groups, with seven rats assigned to each group: group 1 (control), group 2 (sorbitol), and group 3 (LOLA). Intraperitoneal injections were administered five times on post-operative days (PODs) 3, 5, 7, 10, and 12. Perfusion imaging was conducted on PODs 7 and 14 and compared to pre-operative perfusion imaging. Immunohistochemistry staining and Western blotting were performed after the final perfusion imaging. Group 3 showed a significant increase in perfusion, high CD31-positive capillary lumen density, and substantial overexpression of VEGF in the ischemic limb during the subacute phase of HLI. In conclusion, this study provides the first documented evidence of angiogenesis and perfusion recovery in the subacute phase of the HLI model following the administration of LOLA. With LOLA readily available on the commercial market, the implementation of LOLA treatment for PAD in humans can be expedited compared to other therapies still in the developmental stage.

Endothelial ELABELA improves post-ischemic angiogenesis by upregulating VEGFR2 expression

BACKGROUND

Post-ischemic angiogenesis is critical for perfusion recovery and tissue repair. ELABELA (ELA) plays an essential role in embryonic heart development and vasculogenesis. However, the mechanism of ELA on post-ischemic angiogenesis is poorly characterized.

METHODS

We first assessed ELA expression after hind limb ischemia (HLI) in mice. We then established a HLI model in tamoxifen-inducible endothelial-ELA-specific knockout mice (ELAECKO) and assessed the rate of perfusion recovery, capillary density, and VEGFR2 pathway. Knockdown of ELA with lentivirus or siRNA and exogenous addition of ELA peptides were employed to analyze the effects of ELA on angiogenic capacity and VEGFR2 pathway in endothelial cells in vitro. The serum levels of ELA in healthy people and patients with type 2 diabetes mellitus (T2DM) and diabetic foot ulcer (DFU) were detected by a commercial ELISA kit.

RESULTS

In murine HLI models, ELA was significantly up-regulated in the ischemic hindlimb. Endothelial-specific deletion of ELA impaired perfusion recovery and angiogenesis. In physiologic conditions, no significant difference in VEGFR2 expression was found between ELAECKO mice and ELAWT mice. After ischemia, the expression of VEGFR2, p-VEGFR2, and p-AKT was significantly lower in ELAECKO mice than in ELAWT mice. In cellular experiments, the knockdown of ELA inhibited endothelial cell proliferation and tube formation, and the addition of ELA peptides promoted proliferation and tube formation. Mechanistically, ELA upregulated the expression of VEGFR2, p-VEGFR2, and p-AKT in endothelial cells under hypoxic conditions. In clinical investigations, DFU patients had significantly lower serum levels of ELA compared to T2DM patients.

CONCLUSION

Our results indicated that endothelial ELA is a positive regulator of post-ischemic angiogenesis via upregulating VEGFR2 expression. Targeting ELA may be a potential therapeutic option for peripheral arterial diseases.

Current Opinion on Diagnosis of Peripheral Artery Disease in Diabetic Patients

Peripheral arterial disease (PAD) prevalence and diabetes mellitus (DM) prevalence are continuously increasing worldwide. The strong relationship between DM and PAD is highlighted by recent evidence. PAD diagnosis in diabetic patients is very important, particularly in patients with diabetic foot disease (DFD); however, it is often made difficult by the characteristics of such diseases. Diagnosing PAD makes it possible to identify patients at a very high cardiovascular risk who require intensive treatment in terms of risk factor modification and medical therapy. The purpose of this review is to discuss the diagnostic methods that allow for a diagnosis of PAD in diabetic patients. Non-invasive tests that address PAD diagnosis will be discussed, such as the ankle-brachial index (ABI), toe pressure (TP), and transcutaneous oxygen pressure (TcPO2). Furthermore, imaging methods, such as duplex ultrasound (DUS), computed tomography angiography (CTA), magnetic resonance angiography (MRA), and digital subtraction angiography (DSA), are described because they allow for diagnosing the anatomical localization and severity of artery stenosis or occlusion in PAD. Non-invasive tests will also be discussed in terms of their ability to assess foot perfusion. Foot perfusion assessment is crucial in the diagnosis of critical limb ischemia (CLI), the most advanced PAD stage, particularly in DFD patients. The impacts of PAD diagnosis and CLI identification in diabetic patients are clinically relevant to prevent amputation and mortality.

Oral Nanoformulations in Cardiovascular Medicine: Advances in Atherosclerosis Treatment

Atherosclerosis (AS) is the formation of atherosclerotic plaques on the walls of the arteries, causing them to narrow. If this occurs in the coronary arteries, the blood vessels may be completely blocked, resulting in myocardial infarction; if it occurs in the blood vessels of the brain, the blood vessels may be blocked, resulting in cerebral infarction, i.e., stroke. Studies have shown that the pathogenesis of atherosclerosis involves the processes of inflammation, lipid infiltration, oxidative stress, and endothelial damage, etc. SIRT, as a key factor regulating the molecular mechanisms of oxidative stress, inflammation, and aging, has an important impact on the pathogenesis of plaque formation, progression, and vulnerability. Statistics show that AS accounts for about 50 per cent of deaths in Western countries. Currently, oral medication is the mainstay of AS treatment, but its development is limited by side effects, low bioavailability and other unfavourable factors. In recent years, with the rapid development of nano-preparations, researchers have combined statins and natural product drugs within nanopreparations to improve their bioavailability. Based on this, this paper summarises the main pathogenesis of AS and also proposes new oral nanoformulations such as liposomes, nanoparticles, nanoemulsions, and nanocapsules to improve their application in the treatment of AS.

Challenges and opportunities in the management of type 2 diabetes in patients with lower extremity peripheral artery disease: a tailored diagnosis and treatment review

Lower extremity peripheral artery disease (PAD) often results from atherosclerosis, and is highly prevalent in patients with type 2 diabetes mellitus (T2DM). Individuals with T2DM exhibit a more severe manifestation and a more distal distribution of PAD compared to those without diabetes, adding complexity to the therapeutic management of PAD in this particular patient population. Indeed, the management of PAD in patients with T2DM requires a multidisciplinary and individualized approach that addresses both the systemic effects of diabetes and the specific vascular complications of PAD. Hence, cardiovascular prevention is of the utmost importance in patients with T2DM and PAD, and encompasses smoking cessation, a healthy diet, structured exercise, careful foot monitoring, and adherence to routine preventive treatments such as statins, antiplatelet agents, and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. It is also recommended to incorporate glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium-glucose cotransporter-2 inhibitors (SGLT2i) in the medical management of patients with T2DM and PAD, due to their demonstrated cardiovascular benefits. However, the specific impact of these novel glucose-lowering agents for individuals with PAD remains obscured within the background of cardiovascular outcome trials (CVOTs). In this review article, we distil evidence, through a comprehensive literature search of CVOTs and clinical guidelines, to offer key directions for the optimal medical management of individuals with T2DM and lower extremity PAD in the era of GLP-1RA and SGLT2i.

Outcomes of Revascularisation for Treating Lifestyle-Limiting Intermittent Claudication in Aboriginal and Torres Strait Islander People and Non-Indigenous Patients from North Queensland: A Retrospective Cohort Study

Background: This retrospective analysis of an ongoing prospective cohort study aimed to assess the outcome of revascularisation for treating lifestyle-limiting intermittent claudication caused by peripheral artery disease (PAD) in Aboriginal and Torres Strait Islander Peoples and non-Indigenous North Queenslanders. Methods: Consenting patients with PAD who underwent endovascular or open revascularisation procedures for treating lifestyle-limiting intermittent claudication were included. The primary outcome measure was major adverse limb events (MALEs), defined as major amputation or the requirement for repeat open or endovascular revascularisation. Results: Of the 378 included patients, 18 (4.8%) identified as Aboriginal and/or Torres Strait Islander Peoples. During a mean follow-up (standard deviation) of 6.0 (3.9) years, the incidence of MALE was similar in the Aboriginal and Torres Strait Islander People and non-Indigenous Australians (absolute percentage: 50.0% vs. 40.6%, log rank p = 0.59). In both unadjusted and adjusted analyses, Aboriginal and Torres Strait Islander Peoples and non-Indigenous Australians had similar risks of MALE (unadjusted hazard ratio, HR, 1.20, 95% confidence interval, CI, 0.61, 2.36; adjusted HR 1.02, 95%CI 0.50, 2.06). Conclusions: This study suggests that Aboriginal and Torres Strait Islander People are under-represented in the population of patients undergoing revascularisation to treat intermittent claudication. Due to small numbers it cannot be reliably concluded that Aboriginal and Torres Strait Islander People and non-Indigenous Australians have similar rates of MALE.

Hypertension in Patients With Peripheral Artery Disease: An Updated Literature Review

Peripheral artery disease (PAD), a condition where there is reduced blood flow due to narrowing or blockage of the arteries of the peripheral vasculature, is an epidemic that currently affects eight million people in the United States alone and is a major risk equivalent to having active coronary artery disease (CAD). However, it is commonly underdiagnosed in the general population. Hypertension is a common cardiovascular condition characterized by elevated blood pressure levels. There are several mitigating risk factors that can reduce the risk of complications of PAD, with hypertension playing a major role. This literature review aims to explore the relationship between hypertension and PAD, including their shared risk factors, pathophysiological mechanisms, and management strategies. In addition, we will analyze how this impacts major cardiovascular outcomes, such as critical limb ischemia, vascular amputation, myocardial infarction (MI), ischemic stroke, and cardiovascular-related death by examining relevant studies, current guidelines, and evidence. This literature review is intended to guide practitioners on ideal blood pressure parameters and evidence-based anti-hypertensives that provide overall cardiovascular benefit in both the primary care and hospital-based setting. By understanding the association between hypertension and PAD and the underlying pathophysiological mechanisms, healthcare professionals can improve diagnosis, treatment, and management strategies for affected individuals.

Quality of Life Outcomes Following Aortofemoral and Iliofemoral Bypass Surgery in Patients With Peripheral Arterial Disease: A Two-Year Follow-Up Study

INTRODUCTION

Peripheral arterial disease is a circulatory disorder characterized by reduced blood flow to the extremities, predominantly affecting the lower limbs. This study aims to evaluate the impact of aortofemoral and iliofemoral bypass surgeries on patients' quality of life two years post operation and identify predictors of quality-of-life improvements.

METHODS

This cross-sectional study included adult patients with aortoiliac disease who underwent bypass surgery (aortofemoral or iliofemoral) at East Jeddah General Hospital from January 2020 to December 2022. Quality of life was assessed using the Arabic version of the Short Form Health Survey 12 (SF-12) preoperatively and two years postoperatively. Data on sociodemographic factors (age, sex, education, income) and medical factors (smoking, BMI, comorbidities) were collected. Statistical analyses included descriptive statistics, t-tests, one-way ANOVA, and regression analyses using IBM SPSS version 25.0 (IBM Corp., Armonk, NY).

RESULTS

The study included 275 patients. Significant improvements in both physical and mental SF-12 scores were observed postoperatively across all patient groups (P < 0.001). Older age, unemployment, and lower income were associated with lower SF-12 scores. Males had higher postoperative mental scores (P = 0.036). Higher BMI and smoking pack-years negatively correlated with SF-12 scores. Patients with comorbidities had significantly lower preoperative and postoperative SF-12 scores (P < 0.05) but showed significant improvements postoperatively (P < 0.001).

CONCLUSION

Aortofemoral and iliofemoral bypass surgeries significantly improve the quality of life in peripheral arterial disease patients two years post operation. Key predictors of lower quality of life include older age, unemployment, lower income, high BMI, smoking, and comorbidities. Targeted interventions, such as smoking cessation programs, weight management, and comprehensive medical care, are essential for optimizing postoperative outcomes and enhancing patients' physical and mental well-being.

Evaluating the between-day reliability and likelihood of change of a test battery incorporating vastus lateralis muscle thickness, ankle-brachial pressure index, maximal voluntary torque, and six-minute walk test in patients with claudication

OBJECTIVE

The study aims to evaluate the between-day reliability of a proposed test battery for patients with claudication that can be used for monitoring the effectiveness of exercise interventions and other therapeutic strategies tailored to this patient population.

METHODS

Twenty-five men with claudication were recruited. The test battery consisted of the Vastus Lateralis muscle thickness (VL-MT), ankle-brachial pressure index (ABI), unilateral isometric knee extension maximal voluntary torque (MVT) and 6-minute walk test (6MWT). A single investigator conducted the tests for each patient on two separate testing sessions (T1 and T2) 5-7 days apart.

RESULTS

Good to excellent reliability was observed for VL-MT (ICC = 0.95, 95% LOA = ±3.10 mm, SEM = 0.81 mm), ABI (ICC = 0.97, 95% LOA = ±0.10, SEM = 0.02), MVT (ICC = 0.97, 95% LOA = ±24.0 N·m, SEM = 6.31 N·m), 6MWT distance (ICC = 0.99, 95% LOA = ±39.6 m, SEM = 11.0 m), 6MWT time to claudication (ICC = 0.99, 95% LOA = ±30.8 s, SEM = 7.8 s), and 6MWT ratings of pain (ICC = 0.87, 95% LOA = ±2.4 CR-10+, SEM = 0.7 CR-10+ ). Analysis derived from reliability data indicates a change of 1.4 mm for VL-MT, 0.14 for ABI, 12 N·m for MVT, 25 m for 6MWT distance, 15 s for 6MWT time to claudication and 1 CR-10+ for 6MWT ratings of pain is required to be interpreted as the minimum 'likely' change (76% chance).

CONCLUSIONS

The test battery provides a reliable assessment of patients with claudication and can be widely used to evaluate the effects of exercise programmes and other therapeutic interventions. For the individual, changes in VL-MT, ABI, MVT, and 6MWT greater than the minimum likely change as a result of an exercise programme or an intervention are likely changes and less influenced by error associated with the test.

Validation of a New Ankle Brachial Index Measurement System Using Pulse Wave Velocity

Peripheral artery disease (PAD) is a common circulatory disorder characterized by the accumulation of fats, cholesterol, and other substances in the arteries that restrict blood flow to the extremities, especially the legs. The ankle brachial index (ABI) is a highly reliable and valid non-invasive test for diagnosing PAD. However, the traditional method has limitations. These include the time required, the need for Doppler equipment, the training of clinical staff, and patient discomfort. PWV refers to the speed at which an arterial pressure wave propagates along the arteries, and this speed is conditioned by arterial elasticity and stiffness. To address these limitations, we have developed a system that uses electrocardiogram (ECG) and photoplethysmography (PPG) signals to calculate pulse wave velocity (PWV). We propose determining the ABI based on this calculation. Validation was performed on 22 diabetic patients, and the results demonstrate the accuracy of the system, maintaining a margin of ±0.1 compared with the traditional method. This confirms the correlation between PWV and ABI and positions this technique as a promising alternative to overcome some of the limitations of the conventional method.

Effects of additional exercise therapy after a successful vascular intervention for people with symptomatic peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) is characterised by obstruction or narrowing of the large arteries of the lower limbs, usually caused by atheromatous plaques. Most people with PAD who experience intermittent leg pain (intermittent claudication) are typically treated with secondary prevention strategies, including medical management and exercise therapy. Lower limb revascularisation may be suitable for people with significant disability and those who do not show satisfactory improvement after conservative treatment. Some studies have suggested that lower limb revascularisation for PAD may not confer significantly more benefits than supervised exercise alone for improved physical function and quality of life. It is proposed that supervised exercise therapy as adjunctive treatment after successful lower limb revascularisation may confer additional benefits, surpassing the effects conferred by either treatment alone.

OBJECTIVES

To assess the effects of a supervised exercise programme versus standard care following successful lower limb revascularisation in people with PAD.

SEARCH METHODS

We searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, two other databases, and two trial registers, most recently on 14 March 2023.

SELECTION CRITERIA

We included randomised controlled trials which compared supervised exercise training following lower limb revascularisation with standard care following lower limb revascularisation in adults (18 years and older) with PAD.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were maximum walking distance or time (MWD/T) on the treadmill, six-minute walk test (6MWT) total distance, and pain-free walking distance or time (PFWD/T) on the treadmill. Our secondary outcomes were changes in the ankle-brachial index, all-cause mortality, changes in health-related quality-of-life scores, reintervention rates, and changes in subjective measures of physical function. We analysed continuous data by determining the mean difference (MD) and 95% confidence interval (CI), and dichotomous data by determining the odds ratio (OR) with corresponding 95% CI. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified seven studies involving 376 participants. All studies involved participants who received either additional supervised exercise or standard care after lower limb revascularisation. The studies' exercise programmes varied, and included supervised treadmill walking, combined exercise, and circuit training. The duration of exercise therapy ranged from six weeks to six months; follow-up time ranged from six weeks to five years. Standard care also varied between studies, including no treatment or advice to stop smoking, lifestyle modifications, or best medical treatment. We classified all studies as having some risk of bias concerns. The certainty of the evidence was very low due to the risk of bias, inconsistency, and imprecision. The meta-analysis included only a subset of studies due to concerns regarding data reporting, heterogeneity, and bias in most published research. The evidence was of very low certainty for all the review outcomes. Meta-analysis comparing changes in maximum walking distance from baseline to end of follow-up showed no improvement (MD 159.47 m, 95% CI -36.43 to 355.38; I2 = 0 %; 2 studies, 89 participants). In contrast, exercise may improve the absolute maximum walking distance at the end of follow-up compared to standard care (MD 301.89 m, 95% CI 138.13 to 465.65; I2 = 0 %; 2 studies, 108 participants). Moreover, we are very uncertain if there are differences in the changes in the six-minute walk test total distance from baseline to treatment end between exercise and standard care (MD 32.6 m, 95% CI -17.7 to 82.3; 1 study, 49 participants), and in the absolute values at the end of follow-up (MD 55.6 m, 95% CI -2.6 to 113.8; 1 study, 49 participants). Regarding pain-free walking distance, we are also very uncertain if there are differences in the mean changes in PFWD from baseline to treatment end between exercise and standard care (MD 167.41 m, 95% CI -11 to 345.83; I2 = 0%; 2 studies, 87 participants). We are very uncertain if there are differences in the absolute values of ankle-brachial index at the end of follow-up between the intervention and standard care (MD 0.01, 95% CI -0.11 to 0.12; I2 = 62%; 2 studies, 110 participants), in mortality rates at the end of follow-up (OR 0.92, 95% CI 0.42 to 2.00; I2 = 0%; 6 studies, 346 participants), health-related quality of life at the end of follow-up for the physical (MD 0.73, 95% CI -5.87 to 7.33; I2 = 64%; 2 studies, 105 participants) and mental component (MD 1.04, 95% CI -6.88 to 8.95; I2 = 70%; 2 studies, 105 participants) of the 36-item Short Form Health Survey. Finally, there may be little to no difference in reintervention rates at the end of follow-up between the intervention and standard care (OR 0.91, 95% CI 0.23 to 3.65; I2 = 65%; 5 studies, 252 participants).

AUTHORS' CONCLUSIONS

There is very uncertain evidence that additional exercise therapy after successful lower limb revascularisation may improve absolute maximal walking distance at the end of follow-up compared to standard care. Evidence is also very uncertain about the effects of exercise on pain-free walking distance, six-minute walk test distance, quality of life, ankle-brachial index, mortality, and reintervention rates. Although it is not possible to confirm the effectiveness of supervised exercise compared to standard care for all outcomes, studies did not report any harm to participants from this intervention after lower limb revascularisation. Overall, the evidence incorporated into this review was very uncertain, and additional evidence is needed from large, well-designed, randomised controlled studies to more conclusively demonstrate the role additional exercise therapy has after lower limb revascularisation in people with PAD.

Pedal medial arterial calcification in diabetic foot ulcers: A significant risk factor of amputation and mortality

AIMS

Pedal medial arterial calcification (MAC) is frequently observed in individuals with diabetic foot ulcers (DFUs). However, the impact of pedal MAC on individuals with DFUs remains uncertain. The main aim of this study was to evaluate the association between pedal MAC with amputation and mortality outcomes.

METHODS

A prospective, observational cohort study was conducted at West China Hospital from January 2012 to December 2021. Logistic regression analyses, Kaplan-Meier survival method, and Cox proportional hazards models were employed to evaluate the relationship between pedal MAC and amputation as well as mortality.

RESULTS

A total of 979 patients were enrolled in the study. Peripheral artery disease (PAD) was observed in 53% of patients with DFUs, and pedal MAC was found in 8%. Over a median follow-up of 46 (23-72) months, foot amputation was performed on 190 patients, and mortality occurred in 246 patients. Pedal MAC showed a significant association with amputation both in unadjusted analysis (odds ratio [OR] = 2.98, 95% confidence interval [CI] = 1.86-4.76, p < .001) and after adjusting sex, age, albumin levels, hemoglobin levels, and diabetic retinopathy status (OR 2.29, 95% CI 1.33-3.93, p = .003). The risk of amputation was found to be twofold higher in individuals with PAD and pedal MAC compared to those with PAD alone (OR 2.05, 95% CI 1.10-3.82, p = .024). Furthermore, the presence of pedal MAC was significantly associated with an increased risk of mortality (p = .005), particularly among individuals with DFUs but without PAD (HR 4.26, 95% CI 1.90-9.52, p < .001), rather than in individuals presenting with both DFUs and PAD.

CONCLUSION

The presence of pedal MAC is significantly associated with both amputation and mortality in individuals with DFUs. Moreover, pedal MAC could provide additional value to predict amputation other than PAD.

Efficacy and Safety of Covered Stents Versus Bare-Metal Stents for Aortoiliac Occlusive Disease: A Systematic Review and Meta-Analysis

PURPOSE

This study aimed to assess the efficacy and safety outcome of covered stents (CSs), as compared with bare-metal stents (BMSs), for the treatment of patients with aortoiliac occlusive disease (AIOD).

MATERIALS AND METHODS

A systematic literature search was conducted in PubMed, Embase, and Cochrane Library up to August 2023 to identify all studies comparing efficacy and safety outcomes of CSs versus BMSs for treating AIOD. Our outcome was primary patency, secondary patency, technical success, ankle-brachial index (ABI) variation, target lesion revascularization (TLR), limb salvage, complications, and long-term survival. Dichotomous outcomes were pooled as relative risks (RR) or hazard ratio with the 95% confidence interval (CI). Continuous outcomes were pooled as weighted mean differences and 95% CI. Model selection was based on the heterogeneity of the included studies.

RESULTS

There were 10 studies (2 randomized controlled trials, 8 retrospective cohort studies), comprising 1676 sample size. Compared with BMSs, CSs use was associated with better primary patency of patients with a Trans-Atlantic Inter-Society Consensus II (TASC) D lesion (RR, 1.15, 95% CI, 1.04 to 1.27, p=0.007), TLR (RR, 0.39, 95% CI, 0.27 to 0.56, p<0.001), technical success (RR, 1.01, 95% CI, 1.00 to 1.02, p=0.010), and long-term survival (RR, 1.06, 95% CI, 1.01 to 1.11, p=0.020). There is no difference between CSs and BMSs regarding primary patency of all patients, secondary patency, variation in ABI, limb salvage, and complications.

CONCLUSIONS

Compared with BMSs, CSs used in AIOD was associated with more favorable primary patency in patients with TASC D lesions, TLR, technical success rates, and patient long-term survival. These results provide evidence of the advantages of using CSs for AIOD treatment. Future studies focusing on long-term variations in ABI, primary patency of different degrees of calcification, vascular segments, and TASC classification are warranted.

CLINICAL IMPACT

Although several studies evaluated the clinical efficacy of CS in the context of AIOD treatment, the significance and consistency of these findings were not determined to date. We found that CS was used in AIOD associated with better technical success rate, long-term patient survival, lower target lesion revascularization, and higher primary patency of patients with a Trans-Atlantic Inter-Society Consensus II D lesion when compared with BMSs. Our study provides evidence supporting the superiority of CSs over BMSs in the treatment of AIOD, and furnishing clinicians with guidance for treatment decisions.

Promoting collateral formation in type 2 diabetes mellitus using ultra-small nanodots with autophagy activation and ROS scavenging

BACKGROUND

Impaired collateral formation is a major factor contributing to poor prognosis in type 2 diabetes mellitus (T2DM) patients with atherosclerotic cardiovascular disease. However, the current pharmacological treatments for improving collateral formation remain unsatisfactory. The induction of endothelial autophagy and the elimination of reactive oxygen species (ROS) represent potential therapeutic targets for enhancing endothelial angiogenesis and facilitating collateral formation. This study investigates the potential of molybdenum disulfide nanodots (MoS2 NDs) for enhancing collateral formation and improving prognosis.

RESULTS

Our study shows that MoS2 NDs significantly enhance collateral formation in ischemic tissues of diabetic mice, improving effective blood resupply. Additionally, MoS2 NDs boost the proliferation, migration, and tube formation of endothelial cells under high glucose/hypoxia conditions in vitro. Mechanistically, the beneficial effects of MoS2 NDs on collateral formation not only depend on their known scavenging properties of ROS (H2O2, •O2-, and •OH) but also primarily involve a molecular pathway, cAMP/PKA-NR4A2, which promotes autophagy and contributes to mitigating damage in diabetic endothelial cells.

CONCLUSIONS

Overall, this study investigated the specific mechanism by which MoS2 NDs mediated autophagy activation and highlighted the synergy between autophagy activation and antioxidation, thus suggesting that an economic and biocompatible nano-agent with dual therapeutic functions is highly preferable for promoting collateral formation in a diabetic context, thus, highlighting their therapeutic potential.

NIR-II fluorescence imaging without intended excitation light

Nowadays, second near-infrared window (NIR-II) dyes are almost excited by laser diodes, but none of the white light (400-700 nm) excited NIR-II imaging has been studied because of the lack of suitable optical probes. Herein, a novel blue-shifted NIR-II dye, TPA-TQT, has been selected for use in multi-wavelength white light emitting diode (LED) excited NIR-II imaging. This white LED barely caused photo-quenching of the dyes, especially indocyanine green (ICG), whereas the ICG's brightness decreased by 90% under continuous 808 nm laser irradiation. Compared to single-wavelength LED, multi-wavelength LED showed a lower background and similar signal-to-background ratios. This system provided high image resolution to identify blood vessels (103 μm), lymphatic capillaries (129.8 μm), and to monitor hindlimb ischemia-reperfusion and lymphatic inflammation. Furthermore, white LED excited NIR-II fluorescence imaging-guided surgery (FIGS) was successfully performed in 4T1 tumor-bearing mice. Impressively, the lighting LED-based NIR-II FIGS was found to clearly delineate small lesions of metastatic tumors of about ∼350 μm diameter and further was able to guide surgical removal. Overall, multi-wavelength LED-based NIR-II imaging is a promising imaging strategy for tumor delineation and other biomedical applications.

The Role of Cilostazol, a Phosphodiesterase-3 Inhibitor, in the Development of Atherosclerosis and Vascular Biology: A Review with Meta-Analysis

Atherosclerotic cardiovascular disease (ASCVD) stands as the leading global cause of mortality. Addressing this vital and pervasive condition requires a multifaceted approach, in which antiplatelet intervention plays a pivotal role, together with antihypertensive, antidiabetic, and lipid-lowering therapies. Among the antiplatelet agents available currently, cilostazol, a phosphodiesterase-3 inhibitor, offers a spectrum of pharmacological effects. These encompass vasodilation, the impediment of platelet activation and aggregation, thrombosis inhibition, limb blood flow augmentation, lipid profile enhancement through triglyceride reduction and high-density lipoprotein cholesterol elevation, and the suppression of vascular smooth muscle cell proliferation. However, the role of cilostazol has not been clearly documented in many guidelines for ASCVD. We comprehensively reviewed the cardiovascular effects of cilostazol within randomized clinical trials that compared it to control or active agents and involved individuals with previous coronary artery disease or stroke, as well as those with no previous history of such conditions. Our approach demonstrated that the administration of cilostazol effectively reduced adverse cardiovascular events, although there was less evidence regarding its impact on myocardial infarction. Most studies have consistently reported its favorable effects in reducing intermittent claudication and enhancing ambulatory capacity in patients with peripheral arterial disease. Furthermore, cilostazol has shown promise in mitigating restenosis following coronary stent implantation in patients with acute coronary syndrome. While research from more diverse regions is still needed, our findings shed light on the broader implications of cilostazol in the context of atherosclerosis and vascular biology, particularly for individuals at high risk of ASCVD.

Primary results of the brazilian registry of atherothrombotic disease (NEAT)

There is limited contemporary prospective real-world evidence of patients with chronic arterial disease in Latin America. The Network to control atherothrombosis (NEAT) registry is a national prospective observational study of patients with known coronary (CAD) and/or peripheral arterial disease (PAD) in Brazil. A total of 2,005 patients were enrolled among 25 sites from September 2020 to March 2022. Patient characteristics, medications and laboratorial data were collected. Primary objective was to assess the proportion of patients who, at the initial visit, were in accordance with good medical practices (domains) for reducing cardiovascular risk in atherothrombotic disease. From the total of patients enrolled, 2 were excluded since they did not meet eligibility criteria. Among the 2,003 subjects included in the analysis, 55.6% had isolated CAD, 28.7% exclusive PAD and 15.7% had both diagnoses. Overall mean age was 66.3 (± 10.5) years and 65.7% were male patients. Regarding evidence-based therapies (EBTs), 4% were not using any antithrombotic drug and only 1.5% were using vascular dose of rivaroxaban (2.5 mg bid). Only 0.3% of the patients satisfied all the domains of secondary prevention, including prescription of EBTs and targets of body-mass index, blood pressure, LDL-cholesterol, and adherence of lifestyle recommendations. The main barrier for prescription of EBTs was medical judgement. Our findings highlight that the contemporary practice does not reflect a comprehensive approach for secondary prevention and had very low incorporation of new therapies in Brazil. Large-scale populational interventions addressing these gaps are warranted to improve the use of evidence-based therapies and reduce the burden of atherothrombotic disease.ClinicalTrials.gov NCT04677725.

Heparin-Mediated Extracorporeal Low-Density Lipoprotein Precipitation Apheresis for Treating Peripheral Arterial Disease in Patients with Chronic Kidney Disease

Patients with chronic kidney disease (CKD), particularly those with end-stage renal disease (ESRD), have a high prevalence of cardiovascular disease and peripheral arterial disease (PAD). Medical treatment is mainly based on risk factor management, and the surgical approach remains the gold standard treatment in specific conditions. Heparin-mediated extracorporeal low-density lipoprotein precipitation (H.E.L.P.) apheresis is effective in reducing circulating lipoprotein, fibrinogen, inflammatory mediators and procoagulant factors, thereby reducing cardiovascular risk in patients with familial hypercholesterolemia and hypertriglyceridemia. These activities may be effective in reducing symptoms and ischemic vascular lesions even in patients with severe PAD. We reported the application of a treatment protocol with H.E.L.P. apheresis in an ESRD patient with severe PAD without clinical improvement after severe revascularization who was not suitable for further surgical approaches, despite normal LDL cholesterol and lipoprotein (a). The H.E.L.P. protocol was characterized by an intensive first phase with weekly treatments followed by a single session every 10-15 days for 6 months of treatment. The overall clinical condition, foot lesions and walking distance improved significantly after the first 2 months of treatment, and foot amputation was avoided. Here, we review the main pathogenetic mechanisms through which LDL apheresis improves microcirculation and clinical outcomes. Its wider application may represent an optimal therapeutic option for patients unresponsive to standard treatment.

Prevalence and Associations of Peripheral Arterial Disease in China: The Beijing Eye Study

PURPOSE

To explore the prevalence and associations of peripheral arterial disease (PAD) in China.

DESIGN

Population-based incidence estimate and cross-sectional study.

METHODS

The participants (n=3468) of the Beijing Eye Study underwent a detailed ophthalmologic and systemic examination including assessment of the ankle-brachial index (ABI). PAD was defined by an ABI of less than 0.9.

RESULTS

Blood pressure measurements of both arms and ankles were available for 1078 (31.1%) individuals. An ABI (mean: 1.09±0.11; median: 1.10; range: 0.25, 1.36) of <0.9 and <0.95 was found in 32 of 1078 participants (3.0%, 95% CI 2.0, 4.0) and 70 of 1078 individuals (6.5%, 95% CI 5.0, 8.0), respectively. Higher PAD prevalence (multivariable analysis) was associated with older age (odds ratio [OR] 1.08, 95% CI 1.02, 1.15; P = .009), lower level of education (OR 0.62, 95% CI 0.43, 0.90; P = .01), lower quality of life (OR 0.67, 95% CI 1.11, 2.32), higher glucose serum concentration (OR 1.36, 95% CI 1.09, 1.58; P = .006), lower estimated glomerular filtration rate (OR 0.98, 95% CI 0.96, 0.99; P = .04), and higher prevalence of retinal vein occlusions (OR 7.30, 95% CI 1.63, 32.6; P = .009). PAD prevalence was not associated with the prevalence of glaucoma (P = .53) (open-angle glaucoma: P = .42; angle-closure glaucoma: P = .57) and age-related macular degeneration (any AMD: P = .39; early AMD: P = .31; intermediate AMD: P = .92; late AMD: P = .99), prevalence (P = .26) and stage (P = .07) of diabetic retinopathy, prevalence (P = .38) and degree (P = .68) of nuclear cataract, prevalence (P = .39) and degree (P = .72) of cortical cataract, prevalence of subcapsular cataract (P = .86), prevalence of pseudoexfoliation (P = .65), intraocular pressure (P = .50), axial length (P = .56), and peripapillary retinal nerve fiber layer thickness (P = .68).

CONCLUSIONS

The PAD prevalence (3.0%, 95% CI 2.0%, 4.0%) was relatively low in this cohort from rural and urban Beijing, with older age, lower educational level, lower quality of life, higher glucose serum concentration, lower estimated glomerular filtration rate, and higher prevalence of retinal vein occlusions as main associated factors.

Translational Relevance of Advanced Age and Atherosclerosis in Preclinical Trials of Biotherapies for Peripheral Artery Disease

Approximately 6% of adults worldwide suffer from peripheral artery disease (PAD), primarily caused by atherosclerosis of lower limb arteries. Despite optimal medical care and revascularization, many PAD patients remain symptomatic and progress to critical limb ischemia (CLI) and risk major amputation. Delivery of pro-angiogenic factors as proteins or DNA, stem, or progenitor cells confers vascular regeneration and functional recovery in animal models of CLI, but the effects are not well replicated in patients and no pro-angiogenic biopharmacological procedures are approved in the US, EU, or China. The reasons are unclear, but animal models that do not represent clinical PAD/CLI are implicated. Consequently, it is unclear whether the obstacles to clinical success lie in the toxic biochemical milieu of human CLI, or in procedures that were optimized on inappropriate models. The question is significant because the former case requires abandonment of current strategies, while the latter encourages continued optimization. These issues are discussed in the context of relevant preclinical and clinical data, and it is concluded that preclinical mouse models that include age and atherosclerosis as the only comorbidities that are consistently present and active in clinical trial patients are necessary to predict clinical success. Of the reviewed materials, no biopharmacological procedure that failed in clinical trials had been tested in animal models that included advanced age and atherosclerosis relevant to PAD/CLI.

Human ESC-derived vascular cells promote vascular regeneration in a HIF-1α dependent manner

Hypoxia-inducible factor (HIF-1α), a core transcription factor responding to changes in cellular oxygen levels, is closely associated with a wide range of physiological and pathological conditions. However, its differential impacts on vascular cell types and molecular programs modulating human vascular homeostasis and regeneration remain largely elusive. Here, we applied CRISPR/Cas9-mediated gene editing of human embryonic stem cells and directed differentiation to generate HIF-1α-deficient human vascular cells including vascular endothelial cells, vascular smooth muscle cells, and mesenchymal stem cells (MSCs), as a platform for discovering cell type-specific hypoxia-induced response mechanisms. Through comparative molecular profiling across cell types under normoxic and hypoxic conditions, we provide insight into the indispensable role of HIF-1α in the promotion of ischemic vascular regeneration. We found human MSCs to be the vascular cell type most susceptible to HIF-1α deficiency, and that transcriptional inactivation of ANKZF1, an effector of HIF-1α, impaired pro-angiogenic processes. Altogether, our findings deepen the understanding of HIF-1α in human angiogenesis and support further explorations of novel therapeutic strategies of vascular regeneration against ischemic damage.

Nanotechnology translation in vascular diseases: From design to the bench

Atherosclerosis is a systemic pathophysiological condition contributing to the development of majority of polyvascular diseases. Nanomedicine is a novel and rapidly developing science. Due to their small size, nanoparticles are freely transported in vasculature, and have been widely employed as tools in analytical imaging techniques. Furthermore, the application of nanoparticles also allows target intervention, such as drug delivery and tissue engineering regenerative methods, in the management of major vascular diseases. Therefore, by summarizing the physical and chemical characteristics of common nanoparticles used in diagnosis and treatment of vascular diseases, we discuss the details of these applications from cellular, molecular, and in vivo perspectives in this review. Furthermore, we also summarize the status and challenges of the application of nanoparticles in clinical translation. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Cardiovascular Disease Implantable Materials and Surgical Technologies > Nanomaterials and Implants Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Anatomical Distribution Patterns of Peripheral Arterial Disease in the Upper Extremities According to Patient Characteristics: A Retrospective Cohort Study

Purpose

Peripheral arterial disease (PAD) greatly affects the patients' quality of life. We aimed to investigate the affected anatomical sites and distribution patterns in upper extremity PAD using computed tomography angiography (CTA). Furthermore, we sought to identify the correlations between patient characteristics and the identified patterns.

Patients and Methods

This was a retrospective chart review of upper limb CTA findings from patients with symptomatic PAD aged >18 years. Significant variables from univariate logistic regression analysis were further tested using multivariate logistic regression analysis. Statistical significance was set at p < 0.05, with confidence intervals of 95%.

Results

The mean age of the 102 included patients with upper extremity PAD was 55.45 years. Laterality analysis revealed that the upper left limb segments were more affected than the upper right limb segments (42 vs 63; left-to-right ratio, 3:2). The forearm was the segment most affected by stenotic PAD (62 segments, 3.37%). The arm was the segment most affected by occlusive PAD (14 segments, 0.76%). Diabetes mellitus (DM) and hypertension (HTN) were significant predictors of PAD (p = 0.046). In patients with DM, the occlusive form of PAD was dominant in the arm (18.18%); however, the stenotic form prevailed in the forearm (72.72%). In patients with HTN, the occlusive form of PAD was predominant in the arm (45.45%); however, the stenotic form tended to occur in the arm and forearm (90.90%).

Conclusion

The distribution patterns of upper extremity PAD are linked to its underlying pathophysiology. HTN and DM are the most frequent comorbidities in patients with upper extremity PAD. Angiographically, PAD in these patients is likely to present as stenosis rather than as occlusion. This is vital for interventionists who deviate from radial arterial access in patients with PAD. Therefore, targeted screening standards are required, and further studies on PAD are warranted.