Peripheral arterial disease of the lower extremities

Anatomical Distribution Patterns of Peripheral Arterial Disease According to Patient Characteristics: A Unicentral Cohort Study

Purpose

Peripheral arterial disease (PAD) is a common disease with multiple risk factors and affects patients worldwide. Several international studies have established correlations between anatomical topography/distribution of atherosclerosis and comorbidities in patients with PAD. In this cohort study, we aimed to analyze the patterns of atherosclerosis (site, distribution, and degree) in patients who underwent lower limb computed tomography angiography and arterial angiography by identifying the atherosclerotic plaque(s) that were possibly responsible for thrombi. Additionally, we aimed to determine any relationship between comorbidities and identified patterns.

Patients and Methods

Between January 2015 and January 2021, we retrospectively recruited 140 patients at King Fahd Hospital of the University of Saudi Arabia. Data collected included patient characteristics, risk factors, and metabolic disorders, such as hypertension (HTN), diabetes mellitus (DM), dyslipidemia, and chronic kidney disease. Patients with incomplete records or unavailable radiological images were excluded.

Results

The infrapopliteal territory was the most common segment that was affected. HTN, DM, and dyslipidemia were found in 81.4%, 77.9%, and 62.9% of patients, respectively. Correlation analyses revealed that DM was the only independent metabolic disorder associated with a PAD distribution pattern in the femoropopliteal segment (p=0.039), thus denoting distal involvement. No significant association was found between PAD distribution and the severity of stenosis.

Conclusion

Segmental involvement in PAD varies with the risk factors and metabolic comorbidities present in patients. DM is an independent predictor of the anatomical distribution of PAD. The identification of such an anatomical distribution is paramount for screening procedures, early detection of disease, and prevention of complications, particularly limb amputation.

A novel, microvascular evaluation method and device for early diagnosis of peripheral artery disease and chronic limb-threatening ischemia in individuals with diabetes

Objective

A novel transdermal arterial gasotransmitter sensor (TAGS) has been tested as a diagnostic tool for lower limb microvascular disease in individuals with and without diabetes mellitus (DM).

Methods

The TAGS system noninvasively measures hydrogen sulfide (H₂S) emitted from the skin. Measurements were made on the forearm and lower limbs of individuals from three cohorts, including subjects with DM and chronic limb-threatening ischemia, to evaluate skin microvascular integrity. These measurements were compared with diagnosis of peripheral artery disease (PAD) using the standard approach of the toe brachial index. Other measures of vascular health were made in some subjects including fasting blood glucose, hemoglobin A1c, plasma lipids, blood pressure, estimated glomerular filtration, and body mass index.

Results

The leg:arm ratio of H₂S emissions correlated with risk factors for microvascular disease (ie, high-density lipoprotein levels, estimated glomerular filtration rate, systolic blood pressure, and hemoglobin A1c). The ratios were significantly lower in symptomatic DM subjects being treated for chronic limb-threatening ischemia (n = 8, 0.48 ± 0.21) compared with healthy controls (n = 5, 1.08 ± 0.30; P = .0001) and with asymptomatic DM subjects (n = 4, 0.79 ± 0.08; P = .0086). The asymptomatic DM group ratios were also significantly lower than the healthy controls (P = .0194). Using ratios of leg:arm transdermal H₂S measurement (17 subjects, 34 ratios), the overall accuracy to identify limbs with severe PAD had an area under the curve of the receiver operating curve of 0.93.

Conclusions

Ratios of transdermal H₂S measurements are lower in legs with impaired microvascular function, and the decrease in ratio precedes clinically apparent severe microvascular disease and diabetic ulcers. The TAGS instrument is a novel, sensitive tool that may aid in the early detection and monitoring of PAD complications and efforts for limb salvage.

Moderate dose of dietary nitrate improves skeletal muscle microvascular function in patients with peripheral artery disease

Peripheral artery disease (PAD) is an atherosclerotic disease characterized by compromised lower-extremity blood flow that impairs walking ability. We showed that a moderate dose of dietary nitrate in the form of beetroot juice (BRJ, 0.11 mmol/kg) can improve macrovascular function and maximal walking distance in patients with PAD. However, its impacts on the microcirculation and autonomic nervous system have not been examined. Therefore, we investigated the impacts of this dose of dietary nitrate on skeletal muscle microvascular function and autonomic nervous system function and further related these measurements to 6-min walking distance, pain-free walking distance, and exercise recovery in patients with PAD. Patients with PAD (n = 10) ingested either BRJ or placebo in a randomized crossover design. Heart rate variability, skeletal muscle microvascular function, and 6-min walking distance were performed pre- and post-BRJ and placebo. There were significant group × time interactions (P < 0.05) for skeletal muscle microvascular function, 6-min walking distance, and exercise recovery, but no changes (P > 0.05) in heart rate variability or pain-free walking distance were noted. The BRJ group demonstrated improved skeletal muscle microvascular function (∆ 22.1 ± 7.5 %·min-1), longer 6-min walking distance (Δ 37.5 ± 9.1 m), and faster recovery post-exercise (Δ -15.3 ± 4.2 s). Furthermore, changes in skeletal muscle microvascular function were positively associated with changes in 6-min walking distance (r = 0.5) and pain-free walking distance (r = 0.6). These results suggest that a moderate dose of dietary nitrate may support microvascular function, which is related to improvements in walking distance and claudication in patients with PAD.

APLUS: A Python library for usefulness simulations of machine learning models in healthcare

Despite the creation of thousands of machine learning (ML) models, the promise of improving patient care with ML remains largely unrealized. Adoption into clinical practice is lagging, in large part due to disconnects between how ML practitioners evaluate models and what is required for their successful integration into care delivery. Models are just one component of care delivery workflows whose constraints determine clinicians' abilities to act on models' outputs. However, methods to evaluate the usefulness of models in the context of their corresponding workflows are currently limited. To bridge this gap we developed APLUS, a reusable framework for quantitatively assessing via simulation the utility gained from integrating a model into a clinical workflow. We describe the APLUS simulation engine and workflow specification language, and apply it to evaluate a novel ML-based screening pathway for detecting peripheral artery disease at Stanford Health Care.

Association between Femoral Artery Flow-Mediated Dilation and Muscle Oxygen Saturation Parameters in Healthy, Young Individuals

Flow-mediated dilation (FMD) and muscle oxygen saturation (StO₂) are measurements utilized to assess macro- and microvascular function, respectively. Macro- and microvascular dysfunction may occur differently depending on the clinical condition. Since microvascular responsiveness can influence upstream conduit artery hemodynamics, the present study aimed to investigate whether a correlation between FMD and muscle StO₂ parameters exists. Sixteen healthy, young individuals were enrolled in this study. Femoral artery FMD and tibial anterior muscle StO₂ were evaluated by ultrasound and near-infrared spectroscopy, respectively. The FMD and muscle StO₂ parameters were assessed by employing a vascular occlusion test (VOT). The oxygen resaturation rate was determined by calculating the upslope of StO₂ immediately after occlusion and the magnitude of reperfusion as the difference between the highest and lowest StO₂ value achieved during the reperfusion phase. The oxygen desaturation rate and the magnitude of desaturation during the VOT were also evaluated. A significant correlation between the FMD and oxygen resaturation rate (r = 0.628; p = 0.009), magnitude of reperfusion (r = 0.568; p = 0.022), oxygen desaturation rate (r = -0.509; p = 0.044), and magnitude of desaturation (r = 0.644; p = 0.007) was observed. This study demonstrated a moderate association between the femoral artery FMD and tibial anterior StO₂ parameters in young individuals.

Peripheral Arterial Disease and Prosthetic Joint Infection Resulting in Hip Disarticulation: A Case Report

Introduction

The aim of this study was to report a patient with refractory prosthetic joint infection (PJI) and severe peripheral arterial disease that necessitated hip disarticulation (HD), a rare and aggressive procedure. While this is not the first HD performed due to PJI, this is the first reported incidence that deals with profound infection burden along with immense vascular disease that has failed all other treatment options.

Case Report

We report a case of an elderly patient with a prior history of the left total hip arthroplasty, PJI, and severe peripheral arterial disease who underwent a rare HD procedure and was discharged with minimal complications. Before this major surgery, several surgical revisions and antibiotic regimens were attempted. The patient had also failed a revascularization procedure to treat an occlusion stemming from the peripheral arterial disease and had developed a necrotic wound at the surgical site. Irrigation and debridement of associated necrotic tissue was unsuccessful and due to concerns such as cellulitis, HD was performed with patient consent.

Conclusion

HD is a rare procedure that comprises only 1-3% of all lower limb amputations and is reserved for extremely deleterious indications such as infection, ischemia, and trauma. Complication and 5 year mortality rates have been reported to be as high as 60% and 55%, respectively. Despite these rates, the patient case illustrates a situation, in which early detection of indications for HD prevented further negative outcomes. Based on this case, we believe that HD is a reasonable treatment of choice in patients with severe peripheral arterial disease who fail revascularization and prior moderate treatment options. However, the limited availability of data involving HD and variety of comorbid conditions necessitate further analysis in terms of outcomes.

Natural Activators of Autophagy Increase Maximal Walking Distance and Reduce Oxidative Stress in Patients with Peripheral Artery Disease: A Pilot Study

Trehalose, spermidine, nicotinamide, and polyphenols have been shown to display pro-autophagic and antioxidant properties, eventually reducing cardiovascular and ischemic complications. This study aimed to investigate whether a mixture of these components improves maximal walking distance (MWD) in peripheral artery disease (PAD) patients. Nitrite/nitrate (NOx), endothelin-1, sNOX2-dp, H2O2 production, H2O2 break-down activity (HBA), ATG5 and P62 levels, flow-mediated dilation (FMD), and MWD were evaluated in 20 PAD patients randomly allocated to 10.5 g of mixture or no-treatment in a single-blind study. The above variables were assessed at baseline and 60 days after mixture ingestion. Compared with baseline, mixture intake significantly increased MWD (+91%; p < 0.01) and serum NOx (+96%; p < 0.001), whereas it significantly reduced endothelin-1 levels (−30%, p < 0.01). Moreover, mixture intake led to a remarkable reduction in sNOX2dp (−31%, p < 0.05) and H2O2 (−40%, p < 0.001) and potentiated antioxidant power (+110%, p < 0.001). Finally, mixture ingestion restored autophagy by increasing ATG5 (+43%, p < 0.01) and decreasing P62 (−29%, p < 0.05). No changes in the above-mentioned variables were observed in the no-treatment group. The treatment with a mixture of trehalose, spermidine, nicotinamide, and polyphenols improves MWD in PAD patients, with a mechanism possibly related to NOX2-mediated oxidative stress downregulation and autophagic flux upregulation. Clinical Trial Registration unique identifier: NCT04061070.

Mid-Term Outcomes of Endovascular Therapy for TASC II D Femoropopliteal Lesions with Critical Limb Ischaemia: A Retrospective Analysis

OBJECTIVE

This study evaluated the mid-term results of endovascular therapy (EVT) for Trans-Atlantic Inter-Society (TASC) II D femoropopliteal lesions in patients with critical limb ischaemia (CLI).

METHODS

Fifty-seven limbs of 54 patients with CLI due to TASC II D femoropopliteal lesions who underwent EVT at the First Hospital of Hebei Medical University were retrospectively analysed in single-centre, observational study. The patient characteristics, endovascular procedural details, freedom from target lesion revascularisation (TLR), patency rates, ulcer healing rate, and limb salvage rate were accessed.

RESULTS

The patients' mean age was 68.2 ± 8.2 years. All patients were treated by EVT. The final technical success rate was 98.2% (56/57). There were 23 cases of pain at rest, 18 cases of ulcer, and 15 cases of gangrene. The median length of the treated segment was 286 ± 42 mm (56/56) and the mean number of stents placed per patient was 2.0 ± 0.8 (49/56). The postoperative ankle-brachial index (ABI) was significantly higher than that of the preoperative ABI (P < 0.05). The perioperative complication rate was 10.7% (6/56). The re-stenosis or occlusion rate was 44.6% (25/56). The estimated rates of freedom from TLR at 1 year, 2 years, and 3 years were 86.8%, 67.0%, and 62.5%, respectively. Univariate analysis showed that predictors of freedom from TLR were the number of runoff vessels, length of the lesion, and complexity of the lesion, while predictors for re-stenosis or occlusion were the length and the complexity of the lesion. The ulcer healing rate was 93.8%. The limb salvage rates were 76.4%, 74.4%, and 70.9% at 1, 2, and 3 years after treatment, respectively.

CONCLUSIONS

The mid-term outcomes of EVT for TASC II D femoropopliteal lesions in patients with CLI indicated that this treatment approach is safe and effective, and is clinically applicable.

Prevalence of Peripheral Arterial Disease and Associated Vascular Risk Factors in 65-Years-Old People of Northern Barcelona

Objective: To determine the prevalence and risk factors associated with peripheral arterial disease (PAD) in Northern Barcelona at 65 years of age. Methods: A single-center, cross-sectional study, including males and females 65 years of age, health care cardholders of Barcelona Nord. PAD was defined as an ankle–brachial index (ABI) < 0.9. Attending subjects were evaluated for a history of common cardiovascular risk factors. A REGICOR score was obtained, as well as a physical examination and anthropometric measurements. Results: From November 2017 to December 2018, 1174 subjects were included: 479 (40.8%) female and 695 (59.2%) male. Overall prevalence of PAD was 6.2% (95% CI: 4.8–7.6%), being 7.9% (95% CI: 5.9–9.9%) in males and 3.8% (95% CI: 2.1–5.5%) in females. An independent strong association was seen in male smokers and diabetes, with ORs pf 7.2 (95% CI: 2.8–18.6) and 1.8 (95% CI: 1.0–3.3), respectively, and in female smokers and hypertension, with ORs of 5.2 (95% CI: 1.6–17.3) and 3.3 (95% CI: 1.2–9.0). Male subjects presented with higher REGICOR scores (p < 0.001). Conclusion: Higher-risk groups are seen in male subjects with a history of smoking and diabetes and female smokers and arterial hypertension, becoming important subgroups for our primary healthcare centers and should be considered for ABI screening programs.

High-resolution 3D reconstructions of human vasculatures: creation of educational tools and benchtop models for transcatheter devices

Transcatheter therapies are a common way to treat cardiovascular diseases. These therapies are complicated by significant anatomical patient-to-patient variations that exist in terms of transcatheter vascular pathways. Adding to the complexity of transcatheter procedures, the training tools used for physician education often overlook vast patient-to-patient variations and utilize idealized models of patient anatomy that may be unrealistic. In this study, anatomically accurate models were created from high-resolution images of real patient vasculatures. Using fourteen human cadavers donated for research, we collected high-resolution images to generate 3D computational renderings of various patient anatomies. These models make up the "Transcatheter Pathways Vasculature Database" that can be used for physician education and training, as well as improving transcatheter delivery system design. We performed multiple studies that emphasize the anatomical differences that exist in patient vasculatures. Using 3D printing and virtual reality, we developed educational materials and benchtop models to train physicians using true patient anatomies. These tools can also provide device designers with data to improve their products based on real patient vessels. The "Transcatheter Pathways Vasculature Database" highlights differences between patient vasculatures. By educating and training physicians with patient anatomies that accurately represent significant patient-to-patient variations, learning is more translatable to what is seen in the clinic.

The 100 most cited articles in the diagnosis and management of peripheral artery disease

OBJECTIVE

Peripheral artery disease (PAD) is a highly prevalent disease that places major lifestyle limitations and mortality risk on affected individuals. As the understanding of the disease has grown in the medical community, it is unknown which literature has made the greatest impact on the knowledge of PAD. We performed a bibliometric analysis using the number of citations as an indication of impact to analyze the top 100 most influential articles on PAD management.

METHODS

A retrospective search of the Web of Science (Thomson Reuters, New York, NY) database for English-only publications was conducted in November 2020. We identified initial references from the database using the search terms "Peripheral Arterial Disease," "Peripheral Vascular Disease," "Claudication," "Critical Limb Ischemia," "Chronic Limb Threatening Ischemia," "Rest Pain," "Ischemic Ulcer," "Toe Gangrene," "Ankle Brachial Index," and "Leg Ischemia" in Web of Science Core Collections. Articles were ranked based on the number of citations and then analyzed based on citation count and average number of citations per year. Additional metrics included the overall average number of publications per year, the journals, journal discipline, author (including degree and gender), institution, country, topic area, and the level of evidence.

RESULTS

The most popular articles were published between 1959 and 2017, with 46,716 citations in total (average 27.26 citations/y). The most popular article had 2225 citations in total and was Rutherford's "Recommended standards for reports dealing with lower extremity ischemia: Revised version." Peak years of citations were 2016, 2014, and 2018 (2753, 2674, and 2639 citations, respectively). Top journals for the most cited publications were Circulation, Journal of Vascular Surgery, and the Lancet with 21, 13, and 7 articles, respectively. A majority of articles originated from the United States (58 articles), followed by the United Kingdom (15 articles) and Germany (13 articles). Major topic areas of interest and trends in the progressive understanding of PAD were noted. Top areas of focus included surgical interventions (29%), therapeutic angiogenesis (15%), epidemiological studies in PAD (14%), and diagnosis and evaluation (13%). In the top cited literature, 48% (14/29) of surgical articles investigated endovascular interventions for PAD.

CONCLUSIONS

Overall, PAD research has evolved from basic epidemiological studies to advanced management with continued investigation toward future, improved treatments for PAD.

Association of Inflammatory Markers with Multisite Artery Disease in Patients with Peripheral Arterial Disease

INTRODUCTION

Chronic inflammation plays a considerable role in atherosclerosis and may occur simultaneously in different arteries. This condition is referred to as multisite arterial disease (MSAD). We aimed to investigate the association between inflammatory markers and MSAD.

METHODS

In this cross-sectional study we included 526 patients with peripheral artery disease (PAD). Patients with PAD were evaluated by conventional or computed tomography angiography for the presence of coronary artery disease (CAD) and those with at least 30% stenosis were included in the study. Patients were divided into two groups: either MSAD+(PAD and CAD), Group 1) or MSAD- (only PAD without CAD, Group 2). Inflammatory markers were compared between the two groups.

RESULTS

Among all patients, 293 had MSAD while 233 had only PAD. The MSAD+group had higher neutrophil-to-lymphocyte ratio (NLR) and platelet-to-neutrophil ratio (PLR) (5.08±0.19, 4.67±0.51, and 207.1±6.23, 169.3±10.8, respectively, p<0.001). In multivariate analysis, HT [odds ratio (OR): 2.40 (1.61-3.59)); p<0.002], male gender [OR: 2.03 (1.29-3.17); p=0.002], DM [OR:1.56 (1.03-2.36); P=0.035], NLR [OR: 1,08 (1.02-1.16); p=0.021, and PLR [OR:1.05 (1.03-1.08); p<0.001] were found to be associated with MSAD.

CONCLUSION

NLR and PLR are correlated with MSAD and may indicate the extent of atherosclerosis.

Below-the-Knee Intervention for Ischemic Diabetic Foot in Kurdistan, Iraq: A Case-Control Study

BACKGROUND

Management of the ischemic diabetic foot (DF) due to infrapopliteal arterial disease is challenging and controversial. Observation, bypass surgery, and endovascular intervention are the 3 available options. Outcome of percutaneous transluminal angioplasty (PTA) versus conservative therapy is evaluated in this prospective study from Sulaymaniyah, Iraq.

METHODS

Over 2 years starting at January 2018, 40 patients with ischemic DF underwent PTA and compared with a control group (n = 78) of ischemic DF managed conservatively. Besides clinical assessment, all patients underwent Doppler ultrasonography and computed tomography angiography while conventional angiography was reserved for PTA group. Patients who fulfilled the standard angiographic findings underwent standard PTA, and their outcome was compared with the control group.

RESULTS

Mean age was 64 years; 70% (n = 28) were men with a male: female ratio of 2.3: 1. Renal function was impaired in (n = 11, 27.5%), and 7 (17.5%) patients were smokers. The commonest clinical presentation was nonhealing ulcers (n = 39, 97.5%), and most patients (n = 39, 97.5%) had Fontaine IV and Rutherford V-VI grades. Most lesions were anatomically complex; Trans-Atlantic Inter-Society Consensus C and D types, Graziani class ≥4 (75%), long segment (n = 28, 70%), and chronic total occlusion (n = 26, 65%). Success rate was (n = 38, 95%), and no patient died. Ulcer healing was higher (67.5% vs. 34.6%), and ulcer recurrence was lower (20% vs. 47.4%) in PTA group but amputation rate was not significantly different (12.5% vs. 12.8%) (P < 0.05).

CONCLUSIONS

Although amputation and death rates were not significantly different, endovascular intervention achieved better ulcer healing in ischemic DF compared with the conservative approach.

Effects of Physical Rehabilitation on Spatiotemporal Gait Parameters and Ground Reaction Forces of Patients with Intermittent Claudication

Chronic ischemia of the lower extremities often presents as intermittent claudication characterized by lower limb pain which subsides after a short break. This study aimed to provide an assessment of the spatiotemporal parameters of gait and ground reaction forces in patients with PAD participating in three forms of supervised physical training. A total of 80 subjects completed a three-month supervised physical rehabilitation program with three sessions per week. The subjects were assigned to one of three programs: group 1—standard walking training on a treadmill (TT); group 2—Nordic walking (NW) training; group 3—strength and endurance training comprised of NW with isokinetic resistance training (NW + ISO). Gait biomechanics tests (kinematic and kinetic parameters of gait) and a six-minute walk test were carried out before and after three months of physical training. Nordic walking training led to the greatest improvements in the gait pattern of patients with PAD and a significant increase in the absolute claudication distance and total gait distance. Combined training (NW + ISO) by strengthening the muscles of the lower extremities increased the amplitude of the general center of gravity oscillation to the greatest extent. Treadmill training had little effect on the gait pattern. Nordic walking training should be included in the rehabilitation of patients with PAD as a form of gait training, which can be conducted under supervised or unsupervised conditions.

Interpretation of peripheral arterial and venous Doppler waveforms: A consensus statement from the Society for Vascular Medicine and Society for Vascular Ultrasound

This expert consensus statement on the interpretation of peripheral arterial and venous spectral Doppler waveforms was jointly commissioned by the Society for Vascular Medicine (SVM) and the Society for Vascular Ultrasound (SVU). The consensus statement proposes a standardized nomenclature for arterial and venous spectral Doppler waveforms using a framework of key major descriptors and additional modifier terms. These key major descriptors and additional modifier terms are presented alongside representative Doppler waveforms, and nomenclature tables provide context by listing previous alternate terms to be replaced by the new major descriptors and modifiers. Finally, the document reviews Doppler waveform alterations with physiologic changes and disease states, provides optimization techniques for waveform acquisition and display, and provides practical guidance for incorporating the proposed nomenclature into the final interpretation report.

Systematic Literature Review of Randomized Trials Comparing Antithrombotic Therapy Following Revascularization Procedures in Patients With Peripheral Artery Disease

A systematic literature review was conducted to identify and summarize the clinical efficacy and safety of available antithrombotic therapies after peripheral endovascular or surgical revascularization in patients with peripheral artery disease (PAD). Five databases were searched using free-text and Emtree/Mesh terms for PAD, randomized controlled trials (RCTs), and antithrombotic therapies of interest (ie, single antiplatelet therapy, dual antiplatelet therapy, and vitamin K antagonists). Randomized controlled trials were eligible for inclusion if they assessed the risk of thrombotic events (ie, myocardial infarction, ischemic stroke, cardiovascular death, limb ischemia, or limb amputation) or safety profile (ie, minor, moderate, major, or fatal bleeding events) after revascularization. In total, 16 RCTs were identified. Only a few studies reported on treatment effects of the investigated therapies. Myocardial infarction, ischemic stroke, cardiovascular death, and amputation were reported in up to 2.3%, 2.3%, 5.6%, and 7.3% of patients, respectively. Bleeding events were observed in up to 8.4% (major) and 1.5% (fatal) of patients. Despite available treatments, patients with PAD undergoing revascularization remain at risk of thrombotic events. There is a need for new treatments that will help to optimize care for patients with symptomatic PAD undergoing revascularization.

Factors associated with diabetic polyneuropathy-related sensory symptoms and signs in patients with polyneuropathy: A cross-sectional Japanese study (JDDM 52) using a non-linear model

AIMS/INTRODUCTION

To assess the prevalence of diabetic polyneuropathy (DPN)-related sensory symptoms/signs and associated factors in patients with polyneuropathy, considering non-linear effects for numerical variables.

MATERIALS AND METHODS

A cross-sectional survey of patients with type 2 diabetes mellitus from 17 primary care clinics across Japan was carried out. DPN and DPN-related sensory symptoms/signs were diagnosed according to the Diabetic Neuropathy Study Group in Japan criteria.

RESULTS

Of the 9,914 patients with type 2 diabetes mellitus in this study, 2,745 had DPN and 1,689 had DPN-related sensory symptoms/signs (61.5% of patients with DPN). There were significant correlations between DPN-related sensory symptoms/signs and smoking status (odds ratio 2.04 for current and 1.64 for former; P < 0.001 and P = 0.002, respectively), sex (odds ratio 0.56 for male/female; P < 0.001) and alcohol consumption (odds ratio 2.02 for former/never; P = 0.004). Based on the non-linear logistic regression model, significant correlations were observed between the presence of DPN-related sensory symptoms/signs and higher systolic blood pressure (SBP), longer diabetes duration, and decreasing age. The logarithm of odds for SBP increased until reaching approximately 130 mmHg, then it plateaued.

CONCLUSIONS

Some modifiable factors assessed in the large survey database might be associated with DPN-related sensory symptoms/signs, namely smoking, alcohol consumption and SBP. Maintaining SBP <130 mmHg was associated with lower odds of DPN-related sensory symptoms/signs in patients with DPN.

In experimental peripheral arterial disease, type 2 diabetes alters post-ischemic gene expression

Peripheral arterial disease is characterized by impaired blood flow to tissues outside the heart due to atherosclerosis and it most frequently occurs in the lower extremities. Type 2 diabetes (T2D) is a well-known risk factor that accelerate the course and contributes to poor clinical outcomes of PAD. While there is some evidence that T2D is associated with altered expression of genes involved in regulating PAD severity, our knowledge about the specific genes and pathways involved remains incomplete.

We induced experimental PAD or hind limb ischemia in T2D and non-diabetic mice and subjected the ischemic gastrocnemius muscle tissues to genome-wide mRNA transcriptome analysis. We subsequently performed pathway analysis on the top 500 genes that showed the most significant expression differences between the ischemic diabetic and ischemic non-diabetic muscle tissues. Pathway analysis of the differentially expressed genes identified pathways involved in essential biological processes such as “metabolic pathways,” “phagosomes,” “lysosomes,” and “regulation of actin cytoskeleton”. Overall, our data provides the opportunity to test hypotheses on the potential role of the altered genes/molecular pathways in poor PAD outcomes in diabetes.

Type 1 diabetes alters ischemia-induced gene expression

Peripheral Artery Disease (PAD) is a chronic, activity-limiting disease that is caused by atherosclerotic occlusion of blood vessels outside the heart. Type 1 Diabetes (T1D) not only increases an individual’s likelihood of developing PAD, but also contributes to poor clinical outcomes after PAD manifestation. Although there is some evidence suggesting that hyperglycemia might alter expression of genes involved in regulating PAD severity or outcomes, our knowledge about the specific genes and pathways involved remains incomplete.

We induced experimental PAD or hind limb ischemia in T1D and non-diabetic mice and subjected the ischemic gastrocnemius muscle tissues to genome-wide mRNA transcriptome and pathway analysis. We identified 513 probe sets that represented 443 different genes with highly significant expression differences (p < 0.005) between the ischemic diabetic and ischemic non-diabetic muscle tissues. Moreover, pathway analysis of the differentially expressed genes identified pathways involved in essential biological processes such as “cell cycle,” “DNA replication,” “metabolic pathways,” “focal adhesion,” “regulation of actin cytoskeleton,” and “nucleotide excision repair”. Taken together, our data offer the opportunity to test hypotheses on the roles played by the altered genes/molecular pathways in poor PAD outcomes in diabetes. Such studies may lead to the development of specific therapies to improve PAD outcomes in patients with comorbid diabetes.

[Long-term outcomes of spinal neurostimulation in patients with critical lower limb ischemia]

AIM

To evaluate long-term outcomes of spinal neurostimulation (SNS) in patients with critical lower limb ischemia (CLI).

MATERIAL AND METHODS

Long-term outcomes of SNS were assessed in 52 CLI patients. Changes of clinical status were considered by using of Rutherford R.B. et al. scale. Before and in 12 months after SNS percutaneous oxygen partial pressure (TO₂, mm Hg) was measured at the affected lower limb at rest and in orthostatic test. Ankle-brachial index (ABI) was also determined.

RESULTS

SNS improved clinical status in most cases through following effects: 1) reduced pain syndrome and increased motor activity; 2) skin ulcers healing due to increased TO₂ and improved functional state of microcirculation. No augmentation of TO₂ during orthostatic test at TO₂ <10 mm Hg was associated with negative clinical dynamics after SNS (OR 3.2, CI 2.2-54.1, p=0.002). Coronary artery disease with supra-aortic vessels lesion was associated with reduced ABI after SNS (OR 2.1, CI 1.4-3.8, p=0.001).

Social, demographic and clinical characteristics of patients suffering from peripheral vascular disease treated surgically compared to patients treated with endovascular angioplasty

Introduction

Atherosclerosis is the most common cause of chronic lower limb ischaemia. Many factors that have a crucial influence on the development of the disease, its course and prognosis have been identified. The risk factors seem to be subject to interventions due to their susceptibility to changes. It is important to increase the engagement of doctors and nurses performing the screening oriented on risk factors, medical consultation regarding giving up smoking, changing the diet and undertaking physical activity. Therefore, knowledge of the patients’ health situation allows introduction of optimal treatment in this group of patients.

Material and methods

The study group consisted of 119 patients with peripheral artery atherosclerosis, who underwent surgical and endovascular repair. The diagnostic survey method was used in this study. The socio-demographic and clinical data were collected using an originally developed questionnaire. The statistical analysis was performed using the data analysis software system Statistica, version 10.0, by StatSoft Inc. (2011) and an Excel spreadsheet. The statistical significance was set at p < 0.05 for all calculations.

Results

There were statistically significant differences between the analysed groups with regard to severity of ischaemia (p = 0.0001), intermittent claudication (p = 0.0001), rest pain (p = 0.0001), ulceration (p = 0.0031), smoking (p = 0.0075) and comorbidities (percutaneous coronary interventions p = 0.0299; ischaemic stroke p = 0.0235).

Conclusions

There are significantly more patients with more advanced disease and ex-smokers in the surgically treated group. There are significantly more patients with a history of ischaemic stroke, surgical coronary interventions and current smokers in the endovascular group.

Epicardial fat thickness and oxidative stress parameters in patients with subclinical hypothyroidism

INTRODUCTION

Thyroid disorders are known to be a risk factor for cardiovascular diseases. Epicardial fat thickness (EFT) and oxidative stress are also believed to be major risk factors for cardiovascular events. The aim of this study was to evaluate the possible relationship between oxidative stress parameters and EFT in patients with subclinical hypothyroidism (SCH).

MATERIAL AND METHODS

A total of 60 individuals (30 patients with SCH and 30 healthy controls) were recruited for the study. The EFT and oxidative stress parameters of all participants were analyzed at baseline; the same were analyzed in SCH patients after achievement of a euthyroid state.

RESULTS

Compared to healthy subjects, SCH patients had significantly higher EFT and oxidative stress parameters (p < 0.05 for all). EFT and oxidative stress parameters both decreased after treatment, but only the decrease of EFT levels was statistically significant after thyroid hormone replacement (p < 0.05). Serum EFT levels were not significantly correlated with oxidative stress index (r = 0.141, p = 0.458).

CONCLUSIONS

Previous studies have demonstrated that visceral adipose tissue and oxidative stress are major risk factors for cardiovascular events; our study demonstrated that EFT, a visceral adipose tissue, and oxidative stress parameters were higher, and could be used as an indicator for cardiovascular diseases in patients with SCH.

Impact of betablockers on general and local outcome in patients hospitalized for lower extremity peripheral artery disease: The COPART Registry

Lower extremity peripheral artery disease (PAD) is one manifestation of atherosclerosis. Patients with PAD have an increased rate of mortality due to concurrent coronary artery disease and hypertension. Betablockers (BB) may, therefore, be prescribed, especially in case of heart failure. However, BB safety in PAD is controversial, because of presumed peripheral hemodynamic consequences of BB that could lead to worsening of symptoms in patients with PAD. In this context, we aimed to determine the impact of BB on all-cause and cardiovascular mortality and amputation rate at 1 year after hospitalization for PAD from the COPART Registry population. This is a prospective multicenter observational study collecting data from consecutive patients hospitalized for PAD in vascular medicine departments of 4 academic hospitals in France. Patients with, either claudication, critical limb ischemia or acute lower limb ischemia related to a documented PAD were included. We compared the outcomes of patients with BB versus those without BB in their prescription list at hospital discharge. The mean age of the study population was 70.9 years, predominantly composed of males (71%). Among the 1267 patients at admission, 28% were treated by BB for hypertension, prior myocardial infarction or heart failure. During their hospital stay, 40% underwent revascularization (including bypass surgery 29% and angioplasty 74%), 17% required an amputation, and 5% died. In a multivariate analysis, only prior myocardial infarction was found associated with BB prescription with an odds ratio (OR) of 3.11, P < 0.001. Conversely, chronic obstructive pulmonary disease or PAD with ulcer impeded BB prescription (OR: 0.57 and 0.64, P = 0.007; P = 0.001, respectively). One-year overall mortality of patients with BB did not differ from those without (23% vs. 23%, P = 0.95). The 1-year amputation rate did not differ either (4% vs. 6%, P = 0.14). Patients hospitalized for PAD with a BB in their prescription did not worsen their outcome at 1 year compared to patients without BB. Based on these safety data, prospective study could be conducted to assess the effect of BB on long-term mortality and amputation rate in patients with mild, moderate, and severe PAD.

Limb ischemia and vessel regeneration: Is there a role for VEGF?

Vascular endothelial growth factor (VEGF), as an endothelial cell-specific mitogen, is crucial for new blood vessels formation. Atherosclerosis affecting the cardiovascular system causes ischemia and functio laesa in tissues supplied by the occluded vessels. When such a situation occurs in the lower extremities, it causes critical limb ischemia (CLI) often requiring leg amputation. Low oxygen tension leads to upregulation of hypoxia-regulated genes (i.e. VEGF), that should help to restore the impaired blood flow. In CLI these rescue mechanisms are, however, often inefficient. Moreover, there are many contradictory reports showing either induction, no changes or even down-regulation of VEGF in specimens taken from patients with CLI, as well as in samples collected from animals subjected to hindlimb ischemia. Additionally, taking into account numerous experimental and clinical data demonstrating rather insufficient therapeutic potential of VEGF, we called into question the role of this protein in limb ischemia and vessel regeneration. In this review we are also summarizing several aspects which can influence VEGF expression and its measurement in the ischemic tissues.

Same-day discharge after angioplasty for peripheral vascular disease: is it a safe and feasible option?

Peripheral vascular disease affects 20% of the population >55 years of age. Patients who become symptomatic are managed by a number of technique's including medical management, percutaneous angioplasty, bypass surgery, and in nonreconstructable situations, limb amputation. Clinicians treating patients by means of angioplasty have traditionally carried out these procedures on an inpatient basis. Limited resources and pressure on the availability of inpatient beds has necessitated clinicians to reevaluate how many of these patients are managed. Treating suitable patients as day cases is an attractive option that frees up resources and is financially advantageous. This paper examines the feasibility of same-day discharge after angioplasty, with a particular emphasis on achieving safe patient outcomes. It explores how advances in endovascular technologies and techniques have contributed to making same-day discharge an ever more feasible option. Nurse led pre-admission clinics run by specialist nurses facilitate safe and appropriate patient selection, where patients at risk for postprocedural problems can be identified effectively based on predefined clinical criteria.

Intra-arterial Ultra-low-Dose CT Angiography of Lower Extremity in Diabetic Patients

PURPOSE

To image lower extremity arteries by CT angiography using a very low-dose intra-arterial contrast medium in patients with high risk of developing contrast-induced nephropathy (CIN).

MATERIALS AND METHODS

Three cases with long-standing diabetes mellitus and signs of lower extremity atherosclerotic disease were evaluated by CT angiography using 0.1 ml/kg of the body weight of contrast medium given via 10-cm-long 4F introducer by puncturing the CFA. Images were evaluated by an interventional radiologist and a cardiovascular surgeon. Density values of the lower extremity arteries were also calculated. Findings in two cases were compared with digital subtraction angiography images performed for percutaneous revascularization. Blood creatinine levels were followed for possible CIN.

RESULTS

Intra-arterial CT angiography images were considered diagnostic in all patients and optimal in one patient. No patient developed CIN after intra-arterial CT angiography, while one patient developed CIN after percutaneous intervention.

CONCLUSION

Intra-arterial CT angiography of lower extremity might be performed in selected patients with high risk of developing CIN. Our limited experience suggests that as low as of 0.1 ml/kg of the body weight of contrast medium may result in adequate diagnostic imaging.

Safety and efficacy of cell-based therapy on critical limb ischemia: A meta-analysis

BACKGROUND AIMS

Critical limb ischemia (CLI) is a major health problem worldwide, affecting approximately 500-1000 people per million per annum. Cell-based therapy has given new hope for the treatment of limb ischemia. This study assessed the safety and efficacy of cellular therapy CLI treatment.

METHODS

We searched the PubMed, Embase and Cochrane databases through October 20, 2015, and selected the controlled trials with cell-based therapy for CLI treatment compared with cell-free treatment. We assessed the results by meta-analysis using a variety of outcome measures, as well as the association of mononuclear cell dosage with treatment effect by dose-response meta-analysis.

RESULTS

Twenty-five trials were included. For the primary evaluation index, cell-based therapy significantly reduced the rate of major amputation (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.32-0.60, P = 0.000) and significantly increased the rate of amputation-free survival (OR 2.80, 95% CI 1.70-4.61, P = 0.000). Trial sequence analysis indicated that optimal sample size (n = 3374) is needed to detect a plausible treatment effect in all-cause mortality. Cell-based therapy significantly improves ankle brachial index, increases the rate of ulcer healing, increases the transcutaneous pressure of oxygen, reduces limb pain and improves movement ability. Subgroup analysis indicated heterogeneity is caused by type of control, design bias and transplant route. In the dose-response analysis, there was no significant correlation between cell dosage and the therapeutic effect.

CONCLUSIONS

Cell-based therapy has a significant therapeutic effect on CLI, but randomized double-blind placebo-controlled trials are needed to improve the credibility of this conclusion. Assessment of all-cause mortality also requires a larger sample size to arrive at a strong conclusion. In dose-response analysis, increasing the dosage of cell injections does not significantly improve the therapeutic effects of cell-based therapy.

Comparison of results of endovascular stenting and bypass grafting for TransAtlantic Inter-Society (TASC II) type B, C and D iliac occlusive disease

INTRODUCTION

The priority use of endovascular techniques in the management of aortoiliac occlusive disease has increased in the last decade. The aim of the present article is to report 1- and 2-year results of iliac artery stenting (IAS) and aortoiliac grafting in the management of patients with TASC II type B, C and D iliac lesions and chronic limb ischaemia.

MATERIAL AND METHODS

In this prospective, non-randomised, one-centre clinical study, iliac artery stents and vascular grafts used for the treatment of patients with symptomatic lesions in the iliac artery were evaluated. This study enrolled 2 groups: 54 patients in the stent group and 47 patient in the surgery group.

RESULTS

The primary patency rates at 1 and 2 years were 83% and 79.9% after IAS and 97.1% and 97.1% after surgical reconstruction, respectively (p = 0.015). The assisted primary stent patency at 1 and 2 years was 87.9% and 78.2%, respectively. The complication rate was 7.4% in the stent group and 6.3% in the surgery group. There was no perioperative mortality in either group.

CONCLUSIONS

Our results reveal that patients with severe aortoiliac occlusive disease (TASC II types B, C and D) can be treated with IAS or surgically with satisfactory results. Iliac artery stenting is associated with decreased primary patency compared with the surgery group. Iliac artery stenting should be considered with priority in elderly patients or in patients with severe comorbidities.

Health Effects of the Programmed Physical Activities on Lipid Profile in Peripheral Arterial Disease of the Lower Extremities

AIMS

Determine health effects of programmed physical activities on blood fats in peripheral arterial disease of lower limbs or in examinees on medication therapy and examinees performing programmed physical activities along with the medication therapy.

METHODS

Overall research has been carried out at the Clinic for Vascular Disease CCUS. Before involvement into the study, examinees had to meet the inclusion criteria. Research was carried out as randomized controlled trial including 100 patients with arterial disease of lower limbs, who meet inclusion criteria: control group (CG, n=50) and test group (TG, n=50). Total level of cholesterol was used for effects assessment of 28 weeks of applied programmed activity in patients.

RESULTS

Values of total cholesterol (tCh) and triglycerides before and after treatment in patients of CG and TG showed statistically significant change of its mean values. Significant decrease were marked in tCh and triglycerides levels in TG compared to CG.

CONCLUSION

Adequate programmed physical activities in patients with peripheral vascular disease appeared as very successful in treated patients. Results indicate statistically significant decrease of the cholesterol and triglycerides after the treatment. Physical activity used in the treatment made partial regression of arterial diseases and saved patients for undergoing to surgery. Lower level of total cholesterol represents a ten year period prevention of initial stage in progress of arterial diseases.

A randomized phase II study of Xilonix, a targeted therapy against interleukin 1α, for the prevention of superficial femoral artery restenosis after percutaneous revascularization

OBJECTIVE

The purpose of this study was to evaluate an anti-interleukin 1α antibody for its ability to reduce acute postprocedural inflammation, thereby reducing neointimal hyperplasia and restenosis after superficial femoral artery (SFA) angioplasty. Restenosis of the SFA after endovascular intervention is a common problem leading to 1-year primary patency as low as 40%. These failures are primarily due to the development of neointimal hyperplasia, resulting from arterial wall inflammation.

METHODS

This was a randomized, phase II trial examining SFA restenosis in patients after percutaneous revascularization. Randomization occurred after successful revascularization, and patients were assigned to either the standard of care arm or the Xilonix (XBiotech USA, Inc, Austin, Tex) plus standard of care arm (N = 43). Xilonix was administered immediately after revascularization, every 2 weeks intravenously for four doses, and monthly subcutaneously until month 12. The major efficacy end points were target vessel event-free survival and incidence of major adverse cardiovascular events (MACEs).

RESULTS

At 12 months of follow-up, MACE (43% vs 36%; P = .76) and target vessel restenosis (24% vs 27%; log-rank, P = .79) rates were not significantly different between the groups. At 3-month follow-up, which covers the intravenous dosing period, a trend toward lower incidence of restenosis (0 of 22 [0%] vs 2 of 21 [10%]; P = .14) and MACE (2 of 22 [9%] vs 5 of 21 [24%]; P = .22) was observed in the Xilonix cohort. Adverse events were equally distributed in both arms.

CONCLUSIONS

Xilonix was well tolerated. Observed tendency to improved vessel patency with intravenous dosing suggests Xilonix could potentially represent a safe and effective therapeutic approach to preserving vessel patency.

Combined autologous bone marrow mononuclear cell and gene therapy as the last resort for patients with critical limb ischemia

INTRODUCTION

Our study was designed to investigate the safety and efficacy of combined autologous bone marrow mononuclear cell (MNC) and gene therapy in comparison to conventional drug therapy in patients with critical limb ischemia (CLI).

MATERIAL AND METHODS

Thirty-two patients with CLI persisting for 12-48 months (average time 27.5 months) were randomized into 2 groups, each group consisting of 16 patients. In the first group, administration of autologous bone marrow MNC and vascular endothelial growth factor (VEGF) plasmid was performed. The patients from the second group were treated pharmacologically with pentoxifylline. Ankle-brachial index (ABI) was measured and angiography was performed before and finally 3 months after treatment. The pain was evaluated using the Visual Analog Scale (VAS) before and after 3 months.

RESULTS

Ankle-brachial index improved significantly from 0.29 ±0.21 to 0.52 ±0.23 (p < 0.001) in 12 patients (75.0%) 3 months after the experimental therapy in group 1. In this group angiography showed the development of collateral vessels. Ischemic ulcers healed completely in 11 patients (68.75%). In group 2 the ABI did not improve in any patient; moreover the complete healing of skin ulcers was not found in any of the patients of this group. Amputation was performed in 4 (25.0%) patients in group 1, and in 8 patients (50%) from group 2.

CONCLUSIONS

These data after 3-month follow-up indicate that intramuscular injection of MNC combined with gene therapy in patients with chronic CLI is safe, and a more feasible and effective method of treatment than the conventional therapy. However, both therapies are limited by the degree of microcirculation damage.

Improvement of hepatic bioavailability as a new step for the future of statin

Statins (HMG-CoA reductase inhibitors) are a group of highly efficient pharmacological agents used for reducing blood cholesterol level and prevention/treatment of cardiovascular disease. Adverse reactions during statin treatment affect quite significant numbers of patients (reportedly from 5% to 20%), with more side effects occurring at higher doses. Reduced statin dosing can be achieved by improved bioavailability of statins, which is fairly low due to poor aqueous solubility, low permeability and high molecular weight of some members of the statin family. Moreover, since hepatic cholesterologenesis is a main target of statin action and extrahepatic inhibition of HMG-CoA reductase has no effect on plasma lipids, hepatic bioavailability, in our opinion, becomes a new important modality of statins maximizing their potential effect on the plasma lipid profile and diminishing their extrahepatic toxicity. Therefore efficient delivery systems of statins into hepatocytes need to be developed and introduced. Uses of nano-emulsifying statin delivery systems which may include vectors of intrahepatic transport, in particular lycopene, are discussed. As a proof of concept, some preliminary results revealing the effect of a lycopene-containing nanoformulation of simvastatin (designated as Lyco-Simvastatin) on LDL in mildly hypercholesterolemic patients are shown.

Lipid, blood pressure and kidney update 2013

The year 2013 proved to be very exciting as far as landmark trials and new guidelines in the field of lipid disorders, blood pressure and kidney diseases. Among these are the International Atherosclerosis Society Global Recommendations for the Management of Dyslipidemia, European Society of Cardiology (ESC)/European Society of Hypertension Guidelines for the Management of Arterial Hypertension, American Diabetes Association Clinical Practice Recommendations, the Kidney Disease: Improving Global Outcomes Clinical Practice Guidelines for Managing Dyslipidemias in Chronic Kidney Disease (CKD) Patients, the American College of Cardiology/American Heart Association Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults, the Joint National Committee Expert Panel (JNC 8) Evidence-Based Guideline for the Management of High Blood Pressure in Adults, the American Society of Hypertension/International Society of Hypertension Clinical Practice Guidelines for the Management of Hypertension in the Community, the American College of Physicians Clinical Practice Guideline on Screening, Monitoring, and Treatment of Stage 1-3 CKD and many important trials presented among others during the ESC Annual Congress in Amsterdam and the American Society of Nephrology Annual Meeting--Kidney Week in Atlanta, GA. The paper is an attempt to summarize the most important events and reports in the mentioned areas in the passing year.