Pathophysiology of Peripheral Arterial Disease (PAD): A Review on Oxidative Disorders

The m7G methylation modification: An emerging player of cardiovascular diseases

Cardiovascular diseases severely endanger human health and are closely associated with epigenetic dysregulation. N7-methylguanosine (m7G), one of the common epigenetic modifications, is present in many different types of RNA molecules and has attracted significant attention due to its impact on various physiological and pathological processes. Recent studies have demonstrated that m7G methylation plays an important role in the occurrence and development of multiple cardiovascular diseases. Application of small molecule inhibitors to target m7G modification mediated by methyltransferase-like protein 1 (METTL1) has shown potentiality in the treatment of cardiovascular diseases. In this review, we summarize the basic knowledge about m7G modification and discuss its role and therapeutic potential in diverse cardiovascular diseases, aiming to provide a theoretical foundation for future research and therapeutic intervention.

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.

Latest Advancements in Transcutaneous Electrical Nerve Stimulation (TENS) and Electronic Muscle Stimulation (EMS): Revisiting an Established Therapy with New Possibilities

Transcutaneous Electrical Nerve Stimulation (TENS) and Electronic Muscle Stimulation (EMS) are non-invasive therapies widely used for pain relief and neuromuscular adaptation. However, the clinical research supporting the efficacy of TENS in chronic pain management is limited by significant methodological flaws, including small sample sizes and inconsistent reporting of stimulation parameters. TENS modulates pain perception through various techniques, targeting specific nerve fibers and pain pathways. High-frequency TENS is effective for segmental pain control, while low-frequency TENS, reliant on endogenous opioid pathways, may be less effective in opioid-tolerant patients. Additionally, TENS may influence autonomic functions, such as micro-perfusion and sympathetic tone, further broadening its therapeutic potential. EMS, on the other hand, enhances muscle strength and neuromuscular function, particularly in rehabilitation settings, by recruiting additional muscle fibers and improving neuromuscular efficiency. To address the limitations in existing clinical applications, future advancements in TENS and EMS technologies should focus on real-time optimization of stimulation parameters, consistent therapy delivery, and improved accessibility. Integrating automated and personalized adjustments can help streamline treatment, enhance patient compliance, and overcome traditional barriers to the effective implementation of these modalities. Additionally, developing systems that enable remote monitoring and customization of therapy protocols will expand the usability of TENS and EMS in diverse care settings. Future research must focus on rigorous study designs, standardized protocols, and meaningful patient-centered outcomes to fully realize the therapeutic potential of these modalities. Innovations like NXTSTIM EcoAI™ represent a significant advancement in delivering tailored, effective, and patient-friendly pain management and rehabilitation strategies.

Contrast-Enhanced Ultrasound of Mouse Models of Hindlimb Ischemia Reveals Persistent Perfusion Deficits and Distinctive Muscle Perfusion Patterns

OBJECTIVE

Mouse models of hindlimb ischemia (HLI) are used to study peripheral arterial disease and evaluate novel therapies. Contrast-enhanced ultrasound (CEUS) is a noninvasive perfusion measurement technique that is increasingly being employed in these models. The objective of this study was to evaluate two models of severe HLI by CEUS to characterize perfusion recovery and muscle perfusion patterns.

METHODS

Mice undergoing double femoral artery ligation were measured by CEUS and laser Doppler perfusion imaging (LDPI) at baseline and 1-150 d postsurgery. A second group undergoing femoral artery ligation and excision was measured 1-28 d postsurgery.

RESULTS

By LDPI, both surgeries showed robust perfusion recovery by 14 d postsurgery. However, by CEUS only a ∼40% perfusion recovery plateau was reached in either group. These results are consistent with our previous work, employing a less severe single femoral artery ligation, that showed perfusion in the ischemic limb does not return to normal by 150 d postsurgery. Cluster analysis of muscle perfusion patterns indicated 3-5 different patterns at day 1 postsurgery. The double ligation model yielded significantly less variable perfusion patterns, suggesting that it can provide more reproducible results.

CONCLUSION

Contrary to LDPI, perfusion as measured by CEUS never fully recovers after hindlimb surgery, even when followed 28-150 d postsurgery. Individual mice can manifest different patterns of muscle perfusion to the same surgery, but these patterns are conserved within and between different surgical techniques. These results may have significant implications for the evaluation of novel therapeutics to treat PAD in mice.

Lipoprotein Apheresis Alleviates Treatment-Resistant Peripheral Artery Disease Despite the Normal Range of Atherogenic Lipoproteins: The LETS-PAD Study

AIM

Peripheral artery disease (PAD) severely impairs patient prognosis and quality of life (QOL). Although lipoprotein apheresis (LA) has been applied to patients with PAD and elevated serum atherogenic lipoproteins, we hypothesized that LA can be effective for treating PAD even in patients with controlled serum lipoproteins through pleiotropic anti-atherosclerotic effects beyond lipoprotein removal. This study aimed to evaluate the efficacy of LA in patients with treatment-resistant PAD and controlled serum lipoproteins focusing on QOL.

METHODS

In a single-arm prospective study, 30 patients with refractory PAD who had controlled serum lipoproteins underwent sequential LA sessions using dextran sulfate adsorption columns, aiming to complete 10 sessions. The ankle-brachial pressure index (ABI) and vascular QOL (VascuQOL) score were evaluated as the primary outcomes. Secondary outcomes included reactive hyperemia index (RHI) and biological antioxidant potential (BAP) as an endothelial function test and serum antioxidative-capacity evaluation, respectively.

RESULTS

ABI significantly increased after LA sessions (pre-treatment 0.60±0.09 vs. post-treatment 0.65±0.13, p=0.023). Total VascuQOL score (3.7±1.1 vs 4.6±1.1, p＜0.001) and RHI (1.70±0.74 vs 2.34±1.76, p=0.023) significantly improved after the LA sessions. BAP tended to increase after the LA sessions, and the change reached statistical significance 3 months after treatment.

CONCLUSION

ABI and QOL improved after a series of LA sessions in conventional treatment-resistant PAD patients with controlled serum lipoprotein levels. Increased antioxidative capacity and ameliorated endothelial function were observed after the LA treatment.

Outcomes of Patients with Critical Limb Ischemia and Chronic Kidney Disease: A National Perspective

INTRODUCTION

Studies exploring the relationship between peripheral arterial disease (PAD), critical limb ischemia (CLI), and chronic kidney disease (CKD) and its effect on in-hospital outcomes are limited. We aimed to analyze the outcomes of patients with CKD and PAD who are admitted for CLI.

METHODS

We utilized the National Inpatient Sample (NIS) to capture hospitalizations for CLI from 2012 to 2020 and then identified cases with concomitant CKD. The primary outcome was mortality, and secondary outcomes were cerebrovascular accident, major bleeding, vasopressor requirement, percutaneous coronary intervention, cardiac arrest, acute respiratory failure, transfusion, length of stay, and total hospital charges. Multivariable logistic regression was performed to adjust for covariates.

RESULTS

A total of 441,245 patients with CLI were identified, of which 122,370 (27.7%) reported concomitant CKD. Patients with CKD had higher in-patient mortality (odds ratio [OR] 1.68, 95% confidence interval [CI], 1.17-1.68, p < 0.001), vascular complications (OR 1.31, 95% CI, 1.17-1.48, p < 0.001), acute kidney injury requiring hemodialysis (OR 3.17, 95% CI, 2.64-3.80, p < 0.001), and major bleeding (OR 1.12, 95% CI, 1.05-1.19, p < 0.001). Patients with CKD underwent minimally invasive endovascular therapy (31.08% vs. 36.73%, p < 0.0001) and invasive procedures (14.73% vs. 23.55%, p < 0.0001) less often. PAD-CLI with CKD was associated with major (20.54% vs. 16.17%, OR 1.04; p < 0.0001) and minor (26.87% vs. 19.53%, OR 1.2, p < 0.0001) amputations more often.

CONCLUSION

Patients admitted for PAD-CLI with concomitant CKD have significantly higher in-hospital mortality as compared to patients without CKD. Moreover, patients with CKD and PAD-CLI are less likely to receive revascularization and more likely to undergo amputation.

Integrating Toe Brachial Index and longitudinal strain echocardiography for detecting coronary artery disease in patients with diabetic foot syndrome

Coronary artery disease (CAD) is a common problem amongst diabetic foot syndrome (DFS) patients, associated with peripheral arterial disease. This analytic cross-sectional study investigates the diagnostic efficacy of the Toe Brachial Index (TBI) in the detection of CAD in 62 DFS patients. The presence of CAD was assessed by longitudinal strain echocardiography, a sensitive method that provides a more accurate measure of intrinsic left ventricular contractility than left ventricular ejection fraction, especially in diabetic patients. Univariate and multivariate logistic regression identified CAD-associated factors. Receiver operating characteristic curve evaluated TBI and toe pressure's diagnostic performance for CAD. p-Values < 0.05 were considered significant. There was a significant association between TBI and CAD, with each 0.01 increase in TBI associated with a 15% decrease in the odds of CAD development (odds ratio = 0.85, 95% CI: 0.72-0.99, p = 0.039). TBI demonstrated an area under the curve of 0.854, a sensitivity of 80.0% and a specificity of 66.7% at a cut-off of 0.69. Additionally, toe pressure exhibited an area under the curve of 0.845, sensitivity of 74.0% and specificity of 75.0% at a cut-off of 68.0 mmHg. Overall accuracy for TBI and toe pressure was 77.4% and 74.2%, respectively, indicating their potential for CAD risk stratification in the DFS population. This study highlights a significant association between low TBI and the presence of CAD in DFS patients. Consequently, TBI emerges as a valuable screening tool for identifying CAD within this population.

Gene therapy by virus-like self-spooling toroidal DNA condensates for revascularization of hindlimb ischemia

Peripheral arterial diseases (PAD) have been reported to be the leading cause for limb amputations, and the current therapeutic strategies including antiplatelet medication or intervene surgery are reported to not clinically benefit the patients with high-grade PAD. To this respect, revascularization based on angiogenetic vascular endothelial growth factor (VEGF) gene therapy was attempted for the potential treatment of critical PAD. Aiming for transcellular delivery of VEGF-encoding plasmid DNA (pDNA), we proposed to elaborate intriguing virus-like DNA condensates, wherein the supercoiled rigid micrometer-scaled plasmid DNA (pDNA) could be regulated in an orderly fashion into well-defined nano-toroids by following a self-spooling process with the aid of cationic block copolymer poly(ethylene glycol)-polylysine at an extraordinary ionic strength (NaCl: 600 mM). Moreover, reversible disulfide crosslinking was proposed between the polylysine segments with the aim of stabilizing these intriguing toroidal condensates. Pertaining to the critical hindlimb ischemia, our proposed toroidal VEGF-encoding pDNA condensates demonstrated high levels of VEGF expression at the dosage sites, which consequently contributed to the neo-vasculature (the particularly abundant formation of micro-vessels in the injected hindlimb), preventing the hindlimb ischemia from causing necrosis at the extremities. Moreover, excellent safety profiles have been demonstrated by our proposed toroidal condensates, as opposed to the apparent immunogenicity of the naked pDNA. Hence, our proposed virus-like DNA condensates herald potentials as gene therapy platform in persistent expressions of the therapeutic proteins, and might consequently be highlighted in the management of a variety of intractable diseases.

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.

New insight of the efficacy trimetazidine in patients with peripheral arterial disease: a meta-analysis

BACKGROUND

This review aims to examine the impact of trimetazidine on skeletal muscle function in patients suffering from peripheral artery disease (PAD).

METHODS

We searched for studies, both experimental and observational research, concerning the comparison of trimetazidine administration to placebo/standard of care in patients with PAD in PubMed, ScienceDirect, and Cochrane. Meta-analyses of the included studies were performed using Review Manager v5.4. Clinical parameters [ankle-brachial index (ABI) and maximum walking distance (MWD)] were analyzed.

RESULTS

Three observational studies involving 378 participants with PAD satisfied predefined criteria. There was no substantial difference between the examined groups' on ABI (pre- and post-intervention) (MD = - 0.06 [- 0.19 to 0.07], p = 0.38, I2 = 90%). Meanwhile, MWD improvement was significantly higher (MD = 14.15 [6.05-22.25], p = 0.0006, I2 = 37%) in trimetazidine group than in the control group.

CONCLUSIONS

Current evidence from our meta-analysis suggests the beneficial role of trimetazidine's anti-ischemic effect in PAD patients by improving MWD, while it has an insignificant influence on ABI.

Hypertension Related Co-Morbidities and Complications in Women of Sub-Saharan Africa: A Brief Review

Hypertension is the leading cause of cardiovascular disease in women, and sub-Saharan African (SSA) countries have some of the highest rates of hypertension in the world. Expanding knowledge of causes, management, and awareness of hypertension and its co-morbidities worldwide is an effective strategy to mitigate its harms, decrease morbidities and mortality, and improve individual quality of life. Hypertensive disorders of pregnancy (HDPs) are a particularly important subset of hypertension, as pregnancy is a major stress test of the cardiovascular system and can be the first instance in which cardiovascular disease is clinically apparent. In SSA, women experience a higher incidence of HDP compared with other African regions. However, the region has yet to adopt treatment and preventative strategies for HDP. This delay stems from insufficient awareness, lack of clinical screening for hypertension, and lack of prevention programs. In this brief literature review, we will address the long-term consequences of hypertension and HDP in women. We evaluate the effects of uncontrolled hypertension in SSA by including research on heart disease, stroke, kidney disease, peripheral arterial disease, and HDP. Limitations exist in the number of studies from SSA; therefore, we will use data from countries across the globe, comparing and contrasting approaches in similar and dissimilar populations. Our review highlights an urgent need to prioritize public health, clinical, and bench research to discover cost-effective preventative and treatment strategies that will improve the lives of women living with hypertension in SSA.

Inflammation Is a Histological Characteristic of Skeletal Muscle in Chronic Limb Threatening Ischemia

BACKGROUND

The loss of skeletal muscle is a prognostic factor in several diseases including in patients with chronic limb threatening ischemia (CLTI). Patients with CLTI also have a lower skeletal mass and area when compared to those with claudication. However, there are no currently available data regarding the histological characteristics of core muscles in patients with CLTI. This study aims to determine the differences in core skeletal muscles between patients with claudication and those with CLTI. The second aim is to evaluate the differences in myokines, which are molecules secreted by skeletal muscle, between patients with claudication and those with CLTI.

METHODS

An observational, prospective study was conducted from January 2018 to July 2022 involving consecutive patients with peripheral arterial disease (PAD). The clinical characteristics were registered. In PAD patients with surgical indication for common femoral artery approach, samples of sartorius skeletal muscle (and not from the limb muscles directly involved in the ischemic process) were collected. The samples were submitted to histological characterization on hematoxylin-eosin and to immunohistochemical analysis to detect CD45+ leukocytes and CD163+ macrophages. The extent of the inflammatory cells (leukocytes and macrophages) was semiquantitatively assessed using a 0-to-4 grade scale as follows: absent (0†), mild (†), moderate (††), severe (†††), and very severe (††††). Serum levels of myokines: irisin, myostatin, IL-8, and lL-6 were determined with multiplex bead-based immunoassay.

RESULTS

119 patients (mean age: 67.58 ± 9.60 years old, 79.80% males) 64 with claudication and 54 with CLTI were enrolled in the study. No differences were registered between patients with claudication and those with CLTI on age, gender, cardiovascular risk factors, and medication, except on smoking habits. There was a significantly higher prevalence of smokers and a higher smoking load in the claudication group. Samples of sartorius skeletal muscle from 40 patients (14 with claudication and 26 with CLTI) were submitted to histological analysis. No differences were found in skeletal muscle fibers preservation, trauma, or hemorrhage (on hematoxylin-eosin staining). However, in the immunohistochemistry study, we found more inflammatory cells CD45+ leukocytes in patients with CLTI when compared to those with claudication [CD45+ ≥ moderate (††): claudication (n = 14): 4; 28.57%; CLTI (n = 25): 16; 64.00%; P = 0.034]. Patients with CLTI also had higher tissue levels of CD163+ macrophages, but this difference was not significant [CD163+ ≥ moderate (††): claudication (n = 13): 7; 53.85%; CLTI (n = 27): 21; 77.78%; P = 0.122]. The serum levels of the myokines, irisin, and myostatin were below the lower limit of detection, in the majority of patients, so no valid results were obtained. However, patients with CLTI had a higher serum level of Interleukin (IL)-6 and IL-8.

CONCLUSIONS

CLTI patients exhibit increased quantities of leukocytes in their sartorius muscle, as well as elevated serum levels of myokines IL-8 and IL-6. Inflamed skeletal muscle can contribute to the loss of muscle mass and account for the lower density of skeletal muscle observed in CLTI. Additionally, inflamed skeletal muscle may contribute to the development of systemic inflammation through the secretion of pro-inflammatory cytokines into the systemic circulation. Halting the inflammatory process could eventually improve the prognosis of CLTI patients.

Atherosclerosis and Its Related Laboratory Biomarkers

Atherosclerosis constitutes a persistent inflammatory ailment, serving as the predominant underlying condition for coronary artery disease (CAD), peripheral artery disease (PAD), and cerebrovascular disease. The progressive buildup of plaques within the walls of medium- and large-caliber arteries characterizes the atherosclerotic process. This accumulation results in significant narrowing that impedes blood flow, leading to critical tissue oxygen deficiency. Spontaneous blockage of thrombotic vessels can precipitate stroke and myocardial infarction, which are complications representing the primary global causes of mortality. Present-day models for predicting cardiovascular risk incorporate conventional risk factors to gauge the likelihood of cardiovascular events over a ten-year span. In recent times, researchers have identified serum biomarkers associated with an elevated risk of atherosclerotic events. Many of these biomarkers, whether used individually or in combination, have been integrated into risk prediction models to assess whether their inclusion enhances predictive accuracy. In this review, we have conducted a comprehensive analysis of the most recently published literature concerning serum biomarkers associated with atherosclerosis. We have explored the potential utility of incorporating these markers in guiding clinical decisions.

Enhancing Functional Efficiency and Quality of Life through Revascularization Surgery in Peripheral Arterial Disease: A Comparative Analysis of Objective and Subjective Indicators

BACKGROUND This study aimed to compare the ankle-brachial index (ABI), maximal claudication distance (MCD), pain-free walking distance (PFWD), claudication pain, and quality of life (intermittent claudication questionnaire [ICQ]) before and 3 months after revascularization surgery in 98 patients diagnosed with peripheral arterial disease (PAD) at a single center in Poland. MATERIAL AND METHODS Ninety-eight patients were examined (77% men, 23% women, 65.65±7.27 years old), diagnosed with PAD, and qualified for revascularization. The diagnosis of PAD was made on the basis of ABI ≤0.9 and medical records. The patients underwent a noninvasive examination, including measurement of ABI (by Doppler with the EZ8 probe), assessment of the quality of life by ICQ, distance of intermittent claudication on a treadmill using the Gardner-Skinner protocol (including PFWD and MCD), and pain intensity during walking (numeric rating scale [NRS11]). The assessment was carried out twice: 1 to 5 days before surgery and 3 months after surgery. RESULTS There was an increase of ABI (0.4 vs 0.62, P<0.001), PFWD (26.64 vs 80.21, P<0.001), MCD (60.08 vs 181.85, P<0.001), and ICQ (79.92 vs 60.23, P<0.001) and reduction of PFWD pain (7.26 vs 6.05, P<0.001) and MCD pain (9.24 vs 8.11, P<0.001). CONCLUSIONS Revascularization surgery improved the ABI and patients functional efficiency expressed in the improvement of subjective indicators PFWD, MCD, NRS11, and ICQ. Patients who had a longer duration of disease had worse outcomes after revascularization. More attention should be paid to increasing access to preventive examinations aimed at early detection of PAD and the possibility of implementing conservative treatment.

Markers of Restenosis after Percutaneous Transluminal Balloon Angioplasty in Patients with Critical Limb Ischemia

Among cardiovascular diseases, chronic obliterating lesions of the arteries of lower extremities, which are one of the important problems of modern healthcare, are distinguished. In most cases, the cause of damage to the arteries of lower extremities is atherosclerosis. The most severe form is chronic ischemia, characterized by pain at rest and ischemic ulcers, ultimately increasing the risk of limb loss and cardiovascular mortality. Therefore, patients with critical limb ischemia need limb revascularization. Percutaneous transluminal balloon angioplasty is one of the least invasive and safe approaches, with advantages for patients with comorbidities. However, after this procedure, restenosis is still possible. Early detection of changes in the composition of some molecules as markers of restenosis will help screen patients at the risk of restenosis, as well as find ways to apply efforts for further directions of inhibition of this process. The purpose of this review is to provide the most important and up-to-date information on the mechanisms of restenosis development, as well as possible predictors of their occurrence. The information collected in this publication may be useful in predicting outcomes after surgical treatment and will also find new ways for the target implication to the mechanisms of development of restenosis and atherosclerosis.

Incidence and Prevalence of Peripheral Arterial Disease in South Korea: Retrospective Analysis of National Claims Data

BACKGROUND

Peripheral arterial disease (PAD) causes blood vessel narrowing that decreases blood flow to the lower extremities, with symptoms such as leg pain, discomfort, and intermittent claudication. PAD increases risks for amputation, poor health-related quality of life, and mortality. It is estimated that more than 200 million people worldwide have PAD, although the paucity of PAD research in the East detracts from knowledge on global PAD epidemiology. There are few national data-based analyses or health care utilization investigations. Thus, a national data analysis of PAD incidence and prevalence would provide baseline data to enable health promotion strategies for patients with PAD.

OBJECTIVE

This study aims to identify South Korean trends in the incidence and prevalence of PAD and PAD treatment, in-hospital deaths, and health care utilization.

METHODS

This was a retrospective analysis of South Korean national claims data from 2009 to 2018. The incidence of PAD was determined by setting the years 2010 and 2011 as a washout period to exclude previously diagnosed patients with PAD. The study included adults aged ≥20 and <90 years who received a primary diagnosis of PAD between 2011 and 2018; patients were stratified according to age, sex, and insurance status for the incidence and prevalence analyses. Descriptive statistics were used to assess incidence, prevalence, endovascular revascularization (EVR) events, amputations, in-hospital deaths, and the health care utilization characteristics of patients with PAD.

RESULTS

Based on data from 2011 to 2018, there were an average of 124,682 and 993,048 incident and prevalent PAD cases, respectively, in 2018. PAD incidence (per 1000 persons) ranged from 2.68 to 3.09 during the study period. From 2012 to 2018, the incidence rate in both sexes showed an increasing trend. PAD incidence continued to increase with age. PAD prevalence (per 1000 persons) increased steadily, from 3.93 in 2011 to 23.55 in 2018. The number of EVR events varied between 933 and 1422 during the study period, and both major and minor amputations showed a decreasing trend. Health care utilization characteristics showed that women visited clinics more frequently than men, whereas men used tertiary and general hospitals more often than women.

CONCLUSIONS

The number of incident and prevalent PAD cases generally showed an increasing trend. Visits to tertiary and general hospitals were higher among men than women. These results indicate the need for attention not only to Western and male patients, but also to Eastern and female patients with PAD. The results are generalizable, as they are based on national claims data from the entire South Korean population, and they can promote preventive care and management strategies for patients with PAD in clinical and public health settings.

Joint Angle Variability Is Altered in Patients with Peripheral Artery Disease after Six Months of Exercise Intervention

Supervised exercise therapy (SET) is a conservative non-operative treatment strategy for improving walking performance in patients with peripheral artery disease (PAD). Gait variability is altered in patients with PAD, but the effect of SET on gait variability is unknown. Forty-three claudicating patients with PAD underwent gait analysis before and immediately after a 6-month SET program. Nonlinear gait variability was assessed using sample entropy, and the largest Lyapunov exponent of the ankle, knee, and hip joint angle time series. Linear mean and variability of the range of motion time series for these three joint angles were also calculated. Two-factor repeated measure analysis of variance determined the effect of the intervention and joint location on linear and nonlinear dependent variables. After SET, walking regularity decreased, while the stability remained unaffected. Ankle nonlinear variability had increased values compared with the knee and hip joints. Linear measures did not change following SET, except for knee angle, in which the magnitude of variations increased after the intervention. A six-month SET program produced changes in gait variability toward the direction of healthy controls, which indicates that in general, SET improved walking performance in individuals with PAD.

The non-canonical effects of heme oxygenase-1, a classical fighter against oxidative stress

The role of heme oxygenase-1 in resisting oxidative stress and cell protection has always been a hot research topic. With the continuous deepening of research, in addition to directly regulating redox by catalyzing the degradation of heme, HO-1 protein also participates in the gene expression level in a great diversity of methods, thereby initiating cell defense. Particularly the non-canonical nuclear-localized HO-1 and HO-1 protein interactions play the role of a warrior against oxidative stress. Besides, HO-1 may be a promising marker for disease prediction and detection in many clinical trials. Especially for malignant diseases, there may be new advances in the treatment of HO-1 by regulating abnormal ROS and metabolic signaling. The purpose of this review is to systematically sort out and describe several aspects of research to facilitate further detailed mechanism research and clinical application promotion in the future.

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The different subcellular localizations ofHO-1 implies that it has special functions.

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Nuclear HO-1 plays an indispensable role in gene regulation and other aspects.

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The interactions between HO-1 and others provide the possibility to participate in vital physiological processes.

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HO-1 may become a potential disease assessment marker.

Importance of physical detraining in functional capacity of individuals with chronic peripheral arterial occlusive disease: a cross-sectional pilot study

BACKGROUND

Physical training is a well-established strategy for rehabilitation of the functional capacity of individuals with chronic peripheral arterial occlusive disease (PAOD). However, some individuals quit training after participating in a physical training program, undergoing detraining. There is scant literature on the effects of physical detraining in individuals with PAOD and it is therefore important to investigate the effects of this phenomenon.

OBJECTIVES

The objective of this article was to evaluate the effects of physical detraining on functional capacity in individuals with PAOD.

METHODS

Cross-sectional study with 22 individuals. Participants were divided into two groups: a detraining group (DG) and a control group (CG). The distance covered in the 6-minute walk test (6MWTD) and the pain-free walking distance (PFWD) were evaluated. The PFWD is the distance covered until claudication begins, i.e., the distance covered without pain.

RESULTS

Mean age was 66 ± 8 in the DG and 67 ± 7 in the CG. There were no differences between the groups in either the 6MWTD or the PFWD (p = 0.428; p = 0.537, respectively).

CONCLUSIONS

The present pilot study allows us to conclude that the functional capacity of individuals with PAOD who participated in a physical training program and subsequently underwent detraining was not superior in relation to individuals who did not participate in a physical training program. The results of the present study serve to encourage maintenance of physical exercise, since physical training is no longer effective if detraining occurs.

Molecular Mechanisms Associated with ROS-Dependent Angiogenesis in Lower Extremity Artery Disease

Currently, atherosclerosis, which affects the vascular bed of all vital organs and tissues, is considered as a leading cause of death. Most commonly, atherosclerosis involves coronary and peripheral arteries, which results in acute (e.g., myocardial infarction, lower extremities ischemia) or chronic (persistent ischemia leading to severe heart failure) consequences. All of them have a marked unfavorable impact on the quality of life and are associated with increased mortality and morbidity in human populations. Lower extremity artery disease (LEAD, also defined as peripheral artery disease, PAD) refers to atherosclerotic occlusive disease of the lower extremities, where partial or complete obstruction of peripheral arteries is observed. Decreased perfusion can result in ischemic pain, non-healing wounds, and ischemic ulcers, and significantly reduce the quality of life. However, the progressive atherosclerotic changes cause stimulation of tissue response processes, like vessel wall remodeling and neovascularization. These mechanisms of adapting the vascular network to pathological conditions seem to play a key role in reducing the impact of the changes limiting the flow of blood. Neovascularization as a response to ischemia induces sprouting and expansion of the endothelium to repair and grow the vessels of the circulatory system. Neovascularization consists of three different biological processes: vasculogenesis, angiogenesis, and arteriogenesis. Both molecular and environmental factors that may affect the process of development and growth of blood vessels were analyzed. Particular attention was paid to the changes taking place during LEAD. It is important to consider the molecular mechanisms underpinning vessel growth. These mechanisms will also be examined in the context of diseases commonly affecting blood vessel function, or those treatable in part by manipulation of angiogenesis. Furthermore, it may be possible to induce the process of blood vessel development and growth to treat peripheral vascular disease and wound healing. Reactive oxygen species (ROS) play an important role in regulation of essential cellular signaling pathways such as cell differentiation, proliferation, migration and apoptosis. With regard to the repair processes taking place during diseases such as LEAD, prospective therapeutic methods have been described that could significantly improve the treatment of vessel diseases in the future. Summarizing, regenerative medicine holds the potential to transform the therapeutic methods in heart and vessel diseases treatment.