Exercise rehabilitation in peripheral artery disease: functional impact and mechanisms of benefits

Managing Cardiovascular Risk in Patients with Autoimmune Diseases: Insights from a Nutritional Perspective

PURPOSE OF REVIEW

Autoimmune diseases manifest as an immune system response directed against endogenous antigens, exerting a significant influence on a substantial portion of the population. Notably, a leading contributor to morbidity and mortality in this context is cardiovascular disease (CVD). Intriguingly, individuals with autoimmune disorders exhibit a heightened prevalence of CVD compared to the general population. The meticulous management of CV risk factors assumes paramount importance, given the current absence of a standardized solution to this perplexity. This review endeavors to address this challenge from a nutritional perspective.

RECENT FINDINGS

Emerging evidence suggests that inflammation, a common thread in autoimmune diseases, also plays a pivotal role in the pathogenesis of CVD. Nutritional interventions aimed at reducing inflammation have shown promise in mitigating cardiovascular risk. The integration of nutritional strategies into the management plans for patients with autoimmune diseases offers a holistic approach to reducing cardiovascular risk. While conventional pharmacological treatments remain foundational, the addition of targeted dietary interventions can provide a complementary pathway to improve cardiovascular outcomes.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Winners do what they fear: exercise and peripheral arterial disease-an umbrella review

AIMS

This systematic review aims to evaluate and summarize findings from published meta-analyses on the effects of regular exercise in patients with peripheral arterial disease (PAD). The review will assess the impact of exercise on functional parameters, health-related quality of life, haemodynamic parameters, physical activity levels, adverse events, and mortality.

METHODS AND RESULTS

A systematic search was performed in PubMed, Web of Science, Scopus, and Cochrane Library databases (up to May 2023) to identify meta-analyses including randomized controlled trials that examined the effects of regular exercise in patients with PAD. Sixteen studies, with a total of 198 meta-analyses, were identified. Results revealed with strong evidence that patients with PAD who exercised improved functional and health-related quality of life parameters. Specifically, supervised aerobic exercise (i.e. walking to moderate-maximum claudication pain) improves maximum walking distance [mean difference (MD): 177.94 m, 95% confidence interval (CI) 142.29-213.60; P < 0.00001; I2: 65%], pain-free walking distance (fixed MD: 68.78 m, 95% CI 54.35-83.21; P < 0.00001; I2: 67%), self-reported walking ability [i.e. distance score (MD: 9.22 points, 95% CI 5.74-12.70; P < 0.00001; I2: 0%), speed score (MD: 8.71 points, 95% CI 5.64-11.77; P < 0.00001, I2: 0%), stair-climbing score (MD: 8.02 points, 95% CI 4.84-11.21; P < 0.00001, I2: 0%), and combined score (MD: 8.76 points, 95% CI 2.78-14.74; P < 0.0001, I2: 0%)], aerobic capacity (fixed MD: 0.62 mL/kg/min, 95% CI 0.47-0.77, P < 0.00001, I2: 64%), and pain score (MD: 7.65, 95% CI 3.15-12.15; P = 0.0009; I2: 0%), while resistance exercise improves lower limb strength (standardized mean difference: 0.71, 95% CI 0.29-1.13, P = 0.0009; I2: 0%]. Regarding other outcomes, such as haemodynamic parameters, no significant evidence was found, while physical activity levels, adverse events, and mortality require further investigation.

CONCLUSION

Synthesis of the currently available meta-analyses suggests that regular exercise may be beneficial for a broad range of functional tasks improving health-related quality of life in patients with PAD. Supervised aerobic exercise is the best type of exercise to improve walking-related outcomes and pain, while resistance exercise is more effective to improve lower limb strength.

Genetic support of the causal association between gut microbiota and peripheral artery disease: a bidirectional Mendelian randomization study

BACKGROUND

The causal relationship between gut microbiota and peripheral artery disease (PAD) is still not clear. In this research, we employed the Mendelian randomization (MR) technique to explore the potential causal connection between 211 gut microbiota species and PAD. We also investigated whether the causal effects operate in both directions.

METHODS

We used Genome-wide Association Studies (GWAS) summary statistics data from the MiBioGen and FinnGen consortia to conduct a two-sample MR analysis to explore the causal link between gut microbiota and PAD. Sensitivity analysis is conducted to assess the robustness of the MR results. In addition to that, reverse MR analysis was performed to examine the inverse causal relationship.

RESULTS

The inverse variance weighted (IVW) method provided evidence supporting a causal relationship between 9 specific gut microbiota taxa and PAD. The study findings indicated that family Family XI (OR=1.11, CI 1.00-1.24, P=0.048), genus Lachnoclostridium (OR=1.24, 1.02-1.50, P=0.033), and genus Lachnospiraceae UCG001 (OR=1.17, 1.01-1.35, P=0.031) are risk factors associated with PAD. class Actinobacteria (OR=0.84, 0.72-0.99, P=0.034), family Acidaminococcaceae (OR=0.80, 0.66-0.98, P=0.029), genus Coprococcus2 (OR=0.79, 0.64-0.98, P=0.029), genus Ruminococcaceae UCG004 (OR=0.84, 0.72-0.99, P=0.032), genus Ruminococcaceae UCG010 (OR=0.74, 0.58-0.96, P=0.022), and order NB1n (OR=0.88, 0.79-0.98, P=0.02) may be associated with the risk factors of PAD. Moreover, our analysis did not uncover any evidence of a reverse causal relationship between PAD and the nine specific gut microbiota taxa investigated.

CONCLUSIONS

Our MR research has confirmed the potential causal relationship between gut microbiota and PAD while also identifying specific gut bacterial communities associated with PAD.

Examining the role of mood in pain-limited treadmill walking duration in young healthy individuals

PURPOSE

The purpose of the study was to examine the effects of acute mood modulation on treadmill walking duration during experimental pain application.

METHODS

This was a repeated measure, within-subject study design. 30 healthy individuals (Males: Females 16:14; age 22.9 ± 2.5 years; height 170.9 ± 9.5 cm; body mass 68.4 ± 14.6 kg) attended a familiarization session and three experimental sessions, whereby they simultaneously viewed emotionally evoking stimulus from the International Affective Picture System (IAPS) and performed two treadmill walking tests (maximum 10 min duration) with a fixed nociceptive input applied to the thigh (pressure cuff). The primary outcome was treadmill walking duration during pain application to achieve a fixed pain score. During walking, mood (Self-Assessment Manikin: SAM 0-9) and pain (numerical rating scale: NRS 0-10) were measured.

RESULTS

Mood valence scores were significantly different in all conditions (p < 0.001), negative (2.4 ± 0.3), neutral (4.9 ± 0.6) and positive (6.6 ± 0.3). There was a significant difference (p = 0.04) in the treadmill walking duration for different mood states. For the primary outcome, post hoc analysis found differences between the negative and positive mood conditions for the treadmill walking durations to reach pain scores of 3 (negative: 224 ± 49 s; positive: 259 ± 60s, effect size [ES]: 0.80), 4 (negative: 262 ± 59 s; positive: 326 ± 90s, ES: 0.92), 5 (negative: 313 ± 86 s; positive: 385 ± 113 s, ES: 0.90), 6 (negative: 367 ± 106 s; positive: 447 ± 113 s, ES: 1.04) and 7 (negative: 423 ± 114 s; positive: 521 ± 110 s, ES: 1.02). There was no significant difference in the treadmill walking duration between the neutral vs negative mood and neutral vs positive mood conditions.

CONCLUSION

These results highlight the potential psychophysiological impacts on the pain experience in healthy individuals and encourages pursuit in strategies to minimize pain-limited exercise, a highly prevalent issue in the chronic pain population.

SIGNIFICANCE

Walking-based rehabilitation, designed to improve physical activity, has been shown to improve pain and disability. However active participation and adherence in walking-based rehabilitation has shown to be jeopardized by pain and pain-related cognitive and behavioural adaptations. This study examined the effect of a shift in mood on pain perception and treadmill walking tolerance. We found that with a worse mood, individuals were less tolerant of pain and walked on the treadmill for a shorter duration. These results suggest that factors which improve mood should be combined with walking-based training to improve tolerance.

The effects of sedentary behaviour on patients with peripheral arterial Disease: A systematic review

Sedentary behavior has recently emerged as a risk factor for cardiometabolic diseases. The objective of this review was to assess the relationship between sedentary behavior and peripheral arterial disease (PAD). Using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, we performed an electronic search across databases including Cochrane Central Register of Controlled Trials, Embase, MEDLINE (Ovid), CINHAL and PubMed to identify studies focusing on sedentary behavior and PAD. A total of 678 records fulfilled eligibility; 166 duplicates were removed, 487 were excluded at the title and abstract level and 15 studies were excluded at the full article level. Thus, our review comprised 10 studies of 20,064 patients with mean age 67.4 years. The average sedentary time was 544.9 min/day. The current review findings indicate that patients with PAD exhibited prolonged periods of sedentary behavior. Furthermore, sedentary behavior among patients with PAD was associated with lower survival rates. The included studies also reported varied outcomes regarding walking distance with some showing an association between reduced sedentary behavior and increased total walking distance. A randomized controlled trial in this review highlighted that reducing sedentary time among patients with PAD improved walking distance. Therefore, the connection between sedentary behavior and PAD seems to be bidirectional. Sedentary time could contribute to PAD development, and PAD-related symptoms may lead to prolonged sedentary behavior. A call for research investigating the link between PAD and sedentary time. Additionally, intervention studies are needed to target the reduction of sedentary time in patients with PAD.

Prognostic Factors for Restenosis of Superficial Femoral Artery after Endovascular Treatment

High incidence of superficial femoral artery (SFA) restenosis after percutaneous transluminal angioplasty (PTA) poses a persistent challenge in peripheral arterial disease (PAD) treatment. We studied how the patients' and lesions' characteristics, thrombin generation, overall haemostatic potential (OHP), and single nucleotide polymorphisms (SNPs) of the NR4A2 and PECAM1 genes affected the likelihood of restenosis. In total, 206 consecutive PAD patients with limiting intermittent claudication due to SFA stenosis who were treated with balloon angioplasty with bailout stenting when necessary were included. Patients' clinical status and patency of the treated arterial segment on ultrasound examination were assessed 1, 6, and 12 months after the procedure. Restenosis occurred in 45% of patients, with less than 20% of all patients experiencing symptoms. In the multivariate analysis, predictors of restenosis proved to be poor infrapopliteal runoff, higher lesion complexity, absence of treated arterial hypertension, delayed lag phase in thrombin generation, and higher contribution of plasma extracellular vesicles to thrombin concentration. Poor infrapopliteal runoff increased the risk of restenosis in the first 6 months, but not later. The negative effect of poor infrapopliteal runoff on SFA patency opens questions about the potential benefits of simultaneous revascularisation of below-knee arteries along with SFA revascularisation.

Exercise Therapy in the Management of Peripheral Arterial Disease

The incidence and prevalence of peripheral artery disease (PAD) are increasing globally and have a marked economic burden in the United States. The American Heart Association/American College of Cardiology guidelines recommend exercise therapy as a Class 1A, but its utilization remains suboptimal. This state-of-the-art review aims to provide a comprehensive review of the most updated information available on PAD, along with its risk factors, management options, outcomes, economic burden, and the role of exercise therapy in managing PAD.

Six-month effects of supervised exercise on walking ability and health-related factors in peripheral arterial disease: a pilot study

BACKGROUND

In peripheral arterial disease (PAD) patients with intermittent claudication (IC), the combination of aerobic and resistance exercises could counteract muscle loss and attenuate disease progression. This study analyzed the effects of six months of a combined exercise program on walking ability, lower limb body composition, cardiovascular risk factors, and Ankle-Brachial Index (ABI).

METHODS

Twenty-three patients (age 63.2±1.5 years and ABI 0.58±0.07) with PAD and IC were allocated to a control group (CG) or a supervised exercise group (SUP). Ten patients underwent six months of treadmill walking combined with resistance exercises, three times a week. The CG (N.=13) received a recommendation for walking. All patients were measured at baseline (M0), after three months (M3), and six months (M6).

RESULTS

During constant treadmill protocol, the claudication onset time/distance (COT/COD), absolute claudication time/distance (ACT/ACD), and number of pauses of overall patients significantly improved at M3 and M6. Between groups were found significant differences in COT and COD at M6 (P=0.005 and P=0.007, respectively); and in ACT and ACD at M3 (P=0.003 for both) and at M6 (P=0.005 and P=0.005, respectively), with major improvements in the SUP. Over the six months, a significant group effect was found in fat-free mass (P=0.041) and predicted muscle mass (P=0.039) of the lower ABI leg, with greater improvements in the SUP.

CONCLUSIONS

A supervised exercise program that combines aerobic and resistance training improves PAD symptoms and has additional benefits for patients. Patients in the program showed improvements in walking ability, lower-limb body composition, perceived exertion, and heart rate during treadmill walking.

Rehabilitation contributes to lower readmission rates for individuals with peripheral arterial disease: A retrospective observational study

BACKGROUND

Non-pharmacological interventions, such as rehabilitation, are crucial for the treatment of people with peripheral arterial disease (PAD). Although several studies have shown rehabilitation is effective in improving the functional prognosis of PAD, there is currently insufficient evidence regarding its effect on readmission rates.

OBJECTIVES

To examine the impact of rehabilitation on readmission rates for people with PAD.

METHODS

A retrospective analysis of the JMDC hospital database was performed on data from two groups of people aged ≥20 years who were hospitalized between 2014 and 2020 with PAD, as based on a previous diagnosis. Participants were divided according to whether they did, or did not, receive any form of rehabilitation as part of their treatment in hospital. The primary outcome was readmission rates at 30, 60, 90, and 180 days after initial admission. A one-to-one propensity score matching was used to compare readmission rates between rehabilitation and non-rehabilitation groups.

RESULTS

We included 13,453 people with PAD, of whom 2701 pairs (5402 subjects) were selected after being matched in the rehabilitation and non-rehabilitation groups. The rehabilitation group participants had significantly lower mortality and readmission rates at 30, 60, 90, and 180 days. The odds ratios (95% confidence interval) for both groups were 0.79 (0.69-0.91; 30 days), 0.81 (0.71-0.91; 60 days), 0.78 (0.69-0.88; 90 days), and 0.79 (0.71-0.88; 180 days).

CONCLUSIONS

This large, nationwide study found that rehabilitation treatment during hospitalization was associated with lower readmission rates and mortality for people following hospitalization with PAD and supports its inclusion as a standard PAD treatment.

Enhanced external counterpulsation treatment regulates blood flow and wall shear stress metrics in femoral artery: An in vivo study in healthy subjects

As a non-invasive assisted circulation therapy, enhanced external counterpulsation (EECP) has demonstrated potential in treatment of lower-extremity arterial disease (LEAD). However, the underlying hemodynamic mechanism remains unclear. This study aimed to conduct the first prospective investigation of the EECP-induced responses of blood flow behavior and wall shear stress (WSS) metrics in the femoral artery. Twelve healthy male volunteers were enrolled. A Doppler ultrasound-basedapproach was introduced for the in vivo determination of blood flow in the common femoral artery (CFA) and superficial femoral artery (SFA) during EECP intervention, with incremental treatment pressures ranging from 10 to 40 kPa. Three-dimensional subject-specific numerical models were developed in 6 subjects to quantitatively assess variations in WSS-derived hemodynamic metrics in the femoral bifurcation. A mesh-independence analysis was performed. Our results indicated that, compared to the pre-EECP condition, both the antegrade and retrograde blood flow volumes in the CFA and SFA were significantly augmented during EECP intervention, while the heart rate remained constant. The time average shear stress (TAWSS) over the entire femoral bifurcation increased by 32.41%, 121.30%, 178.24%, and 214.81% during EECP with treatment pressures of 10 kPa, 20 kPa, 30 kPa, and 40 kPa, respectively. The mean relative resident time (RRT) decreased by 24.53%, 61.01%, 69.81%, and 77.99%, respectively. The percentage of area with low TAWSS in the femoral artery dropped to nearly zero during EECP with a treatment pressure greater than or equal to 30 kPa. We suggest that EECP is an effective and non-invasive approach for regulating blood flow and WSS in lower extremity arteries.

Double-layered blood vessels over 3 mm in diameter extruded by the inverse-gravity technique

One of the most promising techniques for treating severe peripheral artery disease is the use of cellular tissue-engineered vascular grafts (TEVGs). This study proposes an inverse-gravity (IG) extrusion technique for creating long double-layered cellular TEVGs with diameters over 3 mm. A three-layered coaxial laminar hydrogel flow in an 8 mm-diameter pipe was realised simply by changing the extrusion direction of the hydrogel from being aligned with the direction of gravity to against it. This technique produced an extruded mixture of human aortic smooth muscle cells (HASMCs) and type-I collagen as a tubular structure with an inner diameter of 3.5 mm. After a 21 day maturation period, the maximal burst pressure, longitudinal breaking force, and circumferential breaking force of the HASMC TEVG were 416 mmHg, 0.69 N, and 0.89 N, respectively. The HASMC TEVG was endothelialised with human umbilical vein endothelial cells to form a tunica intima that simulated human vessels. Besides subcutaneous implantability on mice, the double-layered blood vessels showed a considerably lower adherence of platelets and red blood cells once exposed to heparinised mouse blood and were considered nonhaemolytic. The proposed IG extrusion technique can be applied in various fields requiring multilayered materials with large diameters.

ASIC3 plays a protective role in delayed-onset muscle soreness (DOMS) through muscle acid sensation during exercise

Immediate exercise-induced pain (IEIP) and DOMS are two types of exercise-induced muscle pain and can act as barriers to exercise. The burning sensation of IEIP occurs during and immediately after intensive exercise, whereas the soreness of DOMS occurs later. Acid-sensing ion channels (ASICs) within muscle afferents are activated by H+ and other chemicals and have been shown to play a role in various chronic muscle pain conditions. Here, we further defined the role of ASICs in IEIP, and also tested if ASIC3 is required for DOMS. After undergoing exhaustive treadmill exercise, exercise-induced muscle pain was assessed in wild-type (WT) and ASIC3-/- mice at baseline via muscle withdrawal threshold (MWT), immediately, and 24 h after exercise. Locomotor movement, grip strength, and repeat exercise performance were tested at baseline and 24 h after exercise to evaluate DOMS. We found that ASIC3-/- had similar baseline muscle pain, locomotor activity, grip strength, and exercise performance as WT mice. WT showed diminished MWT immediately after exercise indicating they developed IEIP, but ASIC3-/- mice did not. At 24 h after baseline exercise, both ASIC3-/- and WT had similarly lower MWT and grip strength, however, ASIC3-/- displayed significantly lower locomotor activity and repeat exercise performance at 24 h time points compared to WT. In addition, ASIC3-/- mice had higher muscle injury as measured by serum lactate dehydrogenase and creatine kinase levels at 24 h after exercise. These results show that ASIC3 is required for IEIP, but not DOMS, and in fact might play a protective role to prevent muscle injury associated with strenuous exercise.

Home-Based Exercise Therapy in the Management of Intermittent Claudication: A Systematic Review and Meta-Analysis

The current literature strongly supports the use of supervised exercise therapy (SET) as the first-line treatment for symptomatic peripheral arterial disease (PAD) such as intermittent claudication (IC). However, this form of treatment remains underutilised in clinical practice. The home-based exercise therapy (HBET), in which patients must conduct themselves unsupervised is generally less effective than SET in terms of improving functional walking capacity. Nevertheless, it may be a useful alternative where SET is unavailable. The objective of this systematic review is to determine the effectiveness of HBET in reducing symptoms of IC in patients with PAD. Studies eligible for inclusion in this systematic review were parallel-group randomised controlled trials (RCTs) published in the English language that compared the effect of HBET to a comparator arm (SET or no exercise/attention control) in adults with PAD and IC. Studies were eligible if outcome measures were available at baseline and at 12 weeks of follow-up or more. The electronic databases PubMed, Google Scholar, and the Cochrane Library were searched from the earliest records up to January 2021. The Cochrane Collaboration risk of bias tool for RCTs (RoB 2) was used to assess the risk of bias in individual studies, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) classification system was used to appraise the quality of evidence for each outcome across all studies. The primary investigator independently collected, pooled, and analysed the data. The data was then entered into the ReviewManager 5 (RevMan 5) software, and a meta-analysis was performed by using a fixed or random effects model depending on the presence or absence of statistical heterogeneity. The review author identified seven RCTs involving a total of 754 patients which were included in this study. Overall, the risk of bias in the included studies was moderate. Even though the results were variable, this analysis supported the ability of HBET to improve functional walking capacity and self-reported quality of life (QoL) to an extent. This review shows that a home-based exercise intervention with regular professional support and encouragement is beneficial in improving functional walking capacity as well as some aspects of QoL in patients with PAD and IC when compared to no exercise. However, when HBET is compared to hospital-based supervised exercise intervention, SET yields greater benefits.

The Role of Neutrophils in Lower Limb Peripheral Artery Disease: State of the Art and Future Perspectives

In recent years, increasing attention has been paid to the role of neutrophils in cardiovascular (CV) disease (CVD) with evidence supporting their role in the initiation, progression, and rupture of atherosclerotic plaque. Although these cells have long been considered as terminally differentiated cells with a relatively limited spectrum of action, recent research has revealed intriguing novel cellular functions, including neutrophil extracellular trap (NET) generation and inflammasome activation, which have been linked to several human diseases, including CVD. While most research to date has focused on the role of neutrophils in coronary artery and cerebrovascular diseases, much less information is available on lower limb peripheral artery disease (PAD). PAD is a widespread condition associated with great morbidity and mortality, though physician and patient awareness of the disease remains low. To date, several studies have produced some evidence on the role of certain biomarkers of neutrophil activation in this clinical setting. However, the etiopathogenetic role of neutrophils, and in particular of some of the newly discovered mechanisms, has yet to be fully elucidated. In the future, complementary assessment of neutrophil activity should improve CV risk stratification and provide personalized treatments to patients with PAD. This review aims to summarize the basic principles and recent advances in the understanding of neutrophil biology, current knowledge about the role of neutrophils in atherosclerosis, as well as available evidence on their role of PAD.

Home-Based Exercise in Elderly Patients with Claudication and Chronic Kidney Disease Is Associated with Lower Progressive Renal Function Worsening: A 5-Year Retrospective Study

This observational study aimed to monitor the 5-year trends of kidney function in patients with peripheral artery disease (PAD) and concomitant chronic kidney disease (CKD) enrolled or not enrolled into a rehabilitative exercise program. Sixty-six patients (aged 72 ± 10, males n = 52) at KDOQI stages III-IV and PAD at Rutherford's stage I-III were included in the study, with a group (Exercise, EX; n = 32) receiving a 6-month structured pain-free home-based walking program and a group (Control, CO; n = 34) receiving walking advice and optimal nephrological care. Outcomes included kidney function measured through serum creatinine (sCr) and clinical outcomes, including the rate of advance of CKD stages and admission to dialysis, revascularizations, and hospitalizations. At baseline, the two groups were comparable for age, nephropathy, medications, comorbidities, and PAD severity. Patients in the EX group safely completed the exercise program. SCr values were slightly increased in EX (baseline: 2.35 ± 0.32; 5-year: 2.71 ± 0.39 mg/dL) and progressively worsened in CO (baseline: 2.30 ± 0.31; 5-year 4.22 ± 0.42 mg/dL), with a significant between-group difference (p = 0.002). The control group also showed a higher number of dialysis admissions (5 vs. 0, p = 0.025) and advancing CKD stage as well a higher risks for lower limb revascularization (hazard ratio: 2.59; 95%CI: 1.11-6.02; p = 0.027) and for all-cause hospitalization (hazard ratio: 1.77; 95%CI: 1.05-2.97; p = 0.031). PAD-CKD patients enrolled in a low-moderate intensity home-exercise program showed more favorable long-term trends in kidney function and clinical outcomes than patients with usual care. These preliminary observations need to be confirmed in randomized trials.

Exaggerated blood pressure response to static exercise in hindlimb ischemia-reperfusion

Peripheral artery disease (PAD) reduces the blood flow supply in the affected limbs as one of the significant cardiovascular concerns. Revascularization surgery in the femoral artery plays a central role in treating PAD. Exercise is also a rehabilitation strategy suggested for PAD patients to improve vascular functions. However, the effects of limb ischemia-reperfusion (IR), one of the most predominant complications in revascularization surgery, on exercise-induced arterial blood pressure (BP) response are poorly understood. In the present study, we determined 1) the blood flow status in the hindlimb muscles of rats (plantar muscle, red and white portions of gastrocnemius) with different time points of the hindlimb IR; and 2) the BP response to static muscle contraction in rats at different time points after the blood flow reperfusion procedure. Results of this study indicated that, compared with the Sham group, the blood flow in the hindlimb muscles evaluated by Evans blue concentration was significantly reduced at 6 h of femoral artery occlusion (FAO 6 h) (vs. sham control, p < 0.05). The decreased blood flow was gradually recovered after the blood flow reperfusion for 18 (IR 18 h), 66 (IR 66 h), and 114 (IR 114 h) hours (p < 0.05 vs. FAO 6 h for all IR groups). The response of mean arterial pressure was 20 ± 4 mmHg in Sham rats (n = 7); 32 ± 10 mmHg in IR 18 h rats (n = 10); 27 ± 7 mmHg in IR 66 h rats (n = 13); 26 ± 4 mmHg in IR 114 h rats (n = 9) (p < 0.05 vs. Sham for all groups). No significant difference was observed in the peak-developed tension during muscle contraction among all the groups (p > 0.05). In conclusion, static exercise-induced BP response is exaggerated following IR. Whereas the BP response is not statistically significant but tends to decrease with a prolonged IR time, the exaggerated BP response remains through time points from post-IR 18 h-114 h.

A Multicenter, Investigator-Blinded, Randomized Controlled Trial to Assess the Efficacy of Calf Neuromuscular Electrical Stimulation Program on Walking Performance in Peripheral Artery Disease: The ELECTRO-PAD Study Protocol

This paper describes a currently on-going multicenter, randomized controlled trial designed to assess the efficacy of calf neuromuscular electrical stimulation (NMES) on changes in maximal walking distance in people with lower extremity peripheral artery disease (PAD), compared with a non-intervention control-group. This study (NCT03795103) encompasses five participating centers in France. PAD participants with a predominant claudication at the calf level and a maximal treadmill walking distance ≤300 m are randomized into one of the two groups: NMES group or Control group. The NMES program consists of a 12-week program of electrical stimulations at the calf-muscle level. The primary outcome of the study is the change in maximal treadmill walking distance at 12 weeks. Main secondary outcomes include changes in the pain-free treadmill walking distance; 6 min total walking distance; global positioning system (GPS)-measured outdoor walking capacity; daily physical activity level by accelerometry; self-reported walking impairment; self-reported quality of life; ankle-brachial index; and skin microvascular function, both at the forearm and calf levels. Recruitment started in September 2019 and data collection is expected to end in November 2022.

Peripheral vascular remodeling during ischemia

About 230 million people worldwide suffer from peripheral arterial disease (PAD), and the prevalence is increasing year by year. Multiple risk factors, including smoking, dyslipidemia, diabetes, and hypertension, can contribute to the development of PAD. PAD is typically characterized by intermittent claudication and resting pain, and there is a risk of severe limb ischemia, leading to major adverse limb events, such as amputation. Currently, a major progress in the research field of the pathogenesis of vascular remodeling, including atherosclerosis and neointima hyperplasia has been made. For example, the molecular mechanisms of endothelial dysfunction and smooth muscle phenotype switching have been described. Interestingly, a series of focused studies on fibroblasts of the vessel wall has demonstrated their impact on smooth muscle proliferation and even endothelial function via cell-cell communications. In this review, we aim to focus on the functional changes of peripheral arterial cells and the mechanisms of the pathogenesis of PAD. At the same time, we summarize the progress of the current clinical treatment and potential therapeutic methods for PAD and shine a light on future perspectives.

Outcomes following supervised exercise and home-based exercise for patients with intermittent claudication

INTRODUCTION

Intermittent claudication (IC) is the most common symptom of peripheral arterial disease (PAD) which presents as a consequence of muscle ischaemia resulting from the atherosclerotic obstruction to arterial flow. High-quality evidence (Lane et al., 2017) shows that exercise programmes provide important benefits compared with usual care in improving pain-free and maximum walking distance in people with IC, but do not improve ankle-brachial pressure index (ABPI).

METHODS

Retrospective data were analysed to examine walking and ABPI outcomes for participants who completed a 12-week course of supervised or home-based exercise. All participants had a history of IC.

RESULTS

46 participants (mean age 69±11 years; 76% male; 29% current smokers) referred for exercise were assessed, completed a 12-week course of exercise (home-based or supervised) and subsequently attended for re-assessment. Claudication onset distance (COD) increased by 363% (mean improvement 344.7 ± 265.1m; p < .001) and peak walking distance (PWD) by 324.4% in the supervised exercise group; COD increased by 30.6% (mean improvement 32.8 ± 57.2 m; p = 0.026) and PWD by 31.5% in the home-based exercise group. Resting ABPI for the total cohort significantly improved from 0.82 ± 0.25 at A1 to 0.88 ± 0.25 at A2 (p = 0.027).

DISCUSSION

A 12-week course of supervised exercise results in significantly greater walking distance outcomes (COD and PWD) than unmonitored home-based exercise. In contrast with previous findings (Lane et al. 2017), this retrospective study demonstrated a significant improvement in resting ABPI with both supervised exercise as well as home-based exercise.

CONCLUSION

A 12-week programme of exercise favourably influenced walking and ABPI outcomes for patients with IC. Both home-based exercise and supervised individualised exercise increased walking distances, but the magnitude of the improvement in walking outcomes was greater in individuals who attended supervised exercise therapy.

Relationship between serum homocysteine, fibrinogen, lipoprotein-a level, and peripheral arterial disease: a dose-response meta-analysis

AIM

At present, the relationship between serum homocysteine (Hcy), fibrinogen (FIB), lipoprotein-a (LPa), and PAD is uncertain, and there has been no meta-analysis to establish the dose-response relationship between their exposure levels and PAD.

METHODS AND RESULTS

Relevant literature published in PubMed, Embase, and Web of Science was retrieved. The robust error meta-regression method was used to assess the linear and non-linear dose-response relationship between exposure level and PAD risk. A total of 68 articles, involving 565,209 participants, were included. Combined with continuous variables, the serum Hcy, FIB, and LPa levels of PAD patients were significantly higher than those of healthy individuals. The odds ratios (ORs) of PAD for individuals with high Hcy, FIB, and LPa levels compared with those with low levels were 1.47, 1.14, and 1.76, respectively. The study also showed that circulating Hcy, FIB, and LPa were significantly elevated in patients with PAD compared with controls. The level of Hcy and the risk of PAD presented a U-shaped distribution. The nonlinear dose-response model showed that each 1 μmol/L increase in serum Hcy increased the risk of PAD by 7%. Similarly, for each 10 mg/dL FIB and 10 mg/dL LPa increases, the risk of PAD increased by 3% and 6%, respectively.

CONCLUSIONS

This meta-analysis provided evidence that elevated Hcy, PIB, and LPa levels may increase the risk of PAD, and the risk of PAD increases with the increase in serum exposure within a certain range. By controlling Hcy level, the incidence of PAD may be reduced to control the PAD growing epidemic.

TRIAL REGISTRATION NUMBER

PROSPERO (CRD42021250501), https://www.crd.york.ac.uk/prospero/.

Modern possibilities and prospects of conservative treatment of patients with peripheral arterial diseases

The most common clinical manifestation of peripheral arterial disease is intermittent claudication due to insufficient blood supply to the affected limb. The article summarizes and systematizes the latest achievements in the field of conservative treatment of patients with intermittent claudication. In accordance with the requirements of evidence-based medicine, an overview of modern promising trends in conservative therapy presented in the latest Russian and foreign consensus documents, is given. The basis of the complex treatment of patients with peripheral arterial diseases is: non-drug and drug treatment to relieve the symptoms of chronic ischemia, pharmacotherapy for the secondary prevention of cardiovascular complications, open or endovascular revascularization to increase the distance of painfree walking. With the development of atherosclerosis, disturbances in the peptide composition of the endothelium occur, which reduce the ability of the vascular wall to resist inflammation and the associated triggering of pathological processes. It has been experimentally proven that the use of a complex of peptides obtained from the vessels of healthy and young animals in this situation restores the endothelial function of the arteries, affecting the main links of pathogenesis. Decrease in oxidative stress, decrease in atherogenic and lipidemic action, normalization of vascular tone and blood coagulation parameters, increase in the microvascular bed – these are the mechanisms that justify the indication of peptides to patients with atherosclerosis obliterans. Angioprotector based on a complex of polypeptides isolated from blood vessels can become an important part of the treatment of patients with obliterating diseases of the arteries of the lower extremities, providing a complex pathogenetic effect. It is necessary to further study in multicenter clinical trials the duration of the therapeutic effect of a drug in a longer period after a course of treatment, its effect on long-term outcomes of the disease, the possibility of using repeated courses, in chronic obliterating diseases of the arteries of the lower extremities III-IV stages according to the Fontaine classification, as well as the use drug for the treatment of systemic atherosclerosis of various arterial basins.

Carnosine as a potential therapeutic for the management of peripheral vascular disease

AIMS

To evaluate the potential role of carnosine in the management of peripheral vascular disease.

DATA SYNTHESIS

Peripheral vascular disease is growing in its burden and impact; however it is currently under researched, and there are a lack of strong, non-invasive therapeutic options for the clinicians. Carnosine is a dipeptide stored particularly in muscle and brain tissue, which exhibits a wide range of physiological activities, which may be beneficial as an adjunct treatment for peripheral vascular disease. Carnosine's strong anti-inflammatory, antioxidant and antiglycating actions may aid in the prevention of plaque formation, through protective actions on the vascular endothelium, and the inhibition of foam cells. Carnosine may also improve angiogenesis, exercise performance and vasodilatory response, while protecting from ischemic tissue injury.

CONCLUSIONS

Carnosine may have a role as an adjunct treatment for peripheral vascular disease alongside typical exercise and surgical interventions, and may be used in high risk individuals to aid in the prevention of atherogenesis.

CLINICAL RECOMMENDATION

This review identifies a beneficial role for carnosine supplementation in the management of patients with peripheral vascular disease, in conjunction with exercise and revascularization. Carnosine as a supplement is safe, and associated with a host of beneficial effects in peripheral vascular disease and its key risk factors.

Sympathetic Nerve Activity and Blood Pressure Response to Exercise in Peripheral Artery Disease: From Molecular Mechanisms, Human Studies, to Intervention Strategy Development

Sympathetic nerve activity (SNA) regulates the contraction of vascular smooth muscle and leads to a change in arterial blood pressure (BP). It was observed that SNA, vascular contractility, and BP are heightened in patients with peripheral artery disease (PAD) during exercise. The exercise pressor reflex (EPR), a neural mechanism responsible for BP response to activation of muscle afferent nerve, is a determinant of the exaggerated exercise-induced BP rise in PAD. Based on recent results obtained from a series of studies in PAD patients and a rat model of PAD, this review will shed light on SNA-driven BP response and the underlying mechanisms by which receptors and molecular mediators in muscle afferent nerves mediate the abnormalities in autonomic activities of PAD. Intervention strategies, particularly non-pharmacological strategies, improving the deleterious exercise-induced SNA and BP in PAD, and enhancing tolerance and performance during exercise will also be discussed.

Impaired functional exercise capacity and greater cardiovascular response to the 6-min walk test in congenital generalized lipodystrophy

BACKGROUND

Congenital Generalized Lipodystrophy (CGL) is an ultra-rare disease characterized by metabolic disorders. However, the evaluation of functional exercise capacity, cardiovascular (CV) response to exercise, and peripheral arterial disease (PAD) in CGL is scarce. Here we evaluated the performance and CV response to exercise and their association with PAD in CGL compared to healthy individuals.

METHODS

Twelve CGL and 12 healthy subjects matched for age and gender were included. Functional exercise capacity, CV response, and PAD were measured using the six-minute walk test (6MWT) and ankle-brachial index (ABI), respectively.

RESULTS

At baseline, CGL subjects showed reduced predicted walked distance (6MWD) (p = 0.009) and increased heart rate (HR), systolic (SBP), and diastolic (DBP) pressures compared to healthy subjects (p < 0.05). Most CGL subjects presented normal ABI values (1.0 ≤ ABI ≤ 1.4). Only 25% (n = 3) had ABI ≤ 0.9. CGL subjects did not present changes in ABI and blood pressure 12 months after metreleptin (MLP) replacement, but they walked a greater 6MWD than baseline (p = 0.04). Further, 6MWD and right ABI measurements were positively correlated in CGL subjects (p = 0.03). Right ABI negatively correlated with glucose, triglycerides, and VLDL-c (p < 0.05).

CONCLUSIONS

We observed that CGL subjects had lower functional exercise capacity and higher cardiovascular effort for similar performance of 6MWT, suggesting that strategies for decreasing exercise effort in this population should be essential. Furthermore, better physical performance was associated with high ABI in CGL. Additional studies are needed to clarify leptin's role in preserving functional exercise capacity in CGL.

Cardiac Rehabilitation in Peripheral Artery Disease in a Tertiary Center-Impact on Arterial Stiffness and Functional Status after 6 Months

Background and Objectives: Cardiac rehabilitation (CR) plays an essential role in peripheral artery disease (PAD), leading to improved functional status, increased quality of life, and reduced arterial stiffness. We aimed to assess factors associated with clinical improvement 6 months after enrolment in a rehabilitation program at an academic medical center in north-eastern Europe. Materials and Methods: We conducted a prospective cohort study on 97 patients with PAD admitted to a single tertiary referral center. At the 6-months follow-up, 75 patients (77.3%) showed improved clinical status. We analyzed demographics and clinical and paraclinical parameters in order to explore factors associated with a favorable outcome. Results: Hypertension (p = 0.002), diabetes mellitus (p = 0.002), dyslipidemia (p = 0.045), and obesity (p = 0.564) were associated with no clinical improvement. Smoking cessation (p < 0.001), changing sedentary lifestyle (p = 0.032), and improvement of lipid and carbohydrate profile as well as functional status parameters and ambulatory arterial stiffness index (p = 0.008) were factors associated with clinical improvement at the 6-months follow-up. Conclusions: PAD patients require an integrative, multidisciplinary management to maintain functional status and increase quality of life. Improving carbohydrate and lipid profile, adopting a healthy lifestyle, quitting smoking and increasing exercise capacity are predictors for clinical improvement 6 months after enrolment in a CR program.

Near infrared spectroscopy to evaluate the effect of a hybrid exercise programme on peripheral muscle metabolism in patients with intermittent claudication: an exploratory PROSECO-IC sub study

Intermittent claudication (IC) is characterized by decreased blood flow and oxygen delivery to the lower-limb muscles, resulting in pain and impaired functional capacity. This study evaluated the effects of a 12-week hybrid walking intervention on muscle oxygenation and functional capacity in 38 patients with IC (Rutherford I-III). Functional capacity was evaluated by means of two different treadmill test protocols and a six-minute walk test (6MWT). Muscle oxygenation was assessed during the treadmill tests using near-infrared spectroscopy. After the intervention, maximal walking distance was significantly increased (p < 0.001) during the progressive maximal treadmill test (mean (SD): +155 (SD 177) metres) and 6MWT (+18 (SD 29) metres) metres, with concomitant improvements in muscle oxygenation measures. Deoxygenation was slower during the progressive maximal test (p < 0.001) and reoxygenation was faster during recovery (p = 0.045). During the more submaximal test, oxygenated haemoglobin was better preserved (p = 0.040). Slower deoxygenation was more pronounced in the high responders of the progressive maximal treadmill test (p = 0.002). The findings suggest that preserved oxygen availability and slower deoxygenation during exercise could partly explain the improvements in functional capacity.

A Fitness-Fatigue Model of Performance in Peripheral Artery Disease: Predicted and Measured Effects of a Pain-Free Exercise Program

Banister impulse-response (IR) model estimates the performance in response to the training impulses (TRIMPs). In 100 patients with peripheral artery disease (PAD), we tested by an IR model the predictability of the effects of a 6-month structured home-based exercise program. The daily TRIMPs obtained from prescribed walking speed, relative intensity and time of exercise determined the fitness-fatigue components of performance. The estimated performance values, calculated from the baseline 6-min and pain-free walking distance (6MWD and PFWD, respectively) were compared with values measured at visits through regression models. Interval pain-free walking at controlled speed prescribed during circa-monthly hospital visits (5 ± 1) was safely performed at home with good adherence (92% of scheduled sessions, 144 ± 25 km walked in 50 ± 8 training hours). The mean TRIMP rose throughout the program from 276 to 601 a.u. The measured 6MWD and PFWD values increased (+33 m and +121 m, respectively) showing a good fit with those estimated by the IR model (6MWD: R² 0.81; PFWD: R² 0.68) and very good correspondence (correlation coefficients: 0.91 to 0.95), without sex differences. The decay of performance without training was estimated at 18 ± 3 weeks. In PAD, an IR model predicted the walking performance following a pain-free exercise program. IR models may contribute to design and verify personalized training programs.

The Effect of Arterial Disease Level on Outcomes of Supervised Exercise Therapy for Intermittent Claudication: A Prospective Cohort Study

OBJECTIVE

To assess whether level of arterial obstruction determines the effectiveness of SET in patients with IC.

BACKGROUND DATA

Guidelines advocate SET before invasive treatment for IC, but early revascularization remains widespread, especially in patients with aortoiliac disease.

METHODS

Patients were recruited from 10 Dutch centers between October 2017 and October 2018. Participants received SET first, followed by endovascular or open revascularization in case of insufficient effect. They were grouped according to level of stenosis (aortoiliac, femoropopliteal, multilevel, or rest group with no significant stenosis). Changes from baseline walking performance (maximal and functional walking distance on a treadmill test, 6-minute walk test) and vascular quality of life questionnaire-6 at 3 and 6 months were compared, after multivariate adjustment for possible confounders. Freedom from revascularization was estimated with Kaplan-Meier analysis.

RESULTS

Some 267 patients were eligible for analysis (aortoiliac n = 70, 26%; femoropopliteal n = 115, 43%; multilevel n = 69, 26%; rest n = 13, 5%). No between group differences in walking performance or vascular quality of life questionnaire-6 were found. Mean improvement in maximal walking distance after 6 months was 439 m [99% confidence interval (CI) 297-581], 466 m (99% CI 359-574), 353 m (99% CI 210-496), and 403 m (99% CI 58-749), respectively (P = 0.40). Freedom from intervention was 73.9% for aortoiliac disease and 88.6% for femoropopliteal disease (hazard ratio 2.46, 99% CI 0.96 - 6.30, P = 0.013).

CONCLUSIONS

Short-term effectiveness of SET for IC is not determined by the location of stenosis. Although aortoiliac disease patients improved walking performance and health-related quality of life similarly compared to other arterial disease level groups, they underwent revascularization more often.

Supervised exercise therapy for patients with peripheral artery disease: Clinical update and pathways forward

Peripheral artery disease (PAD) is an atherosclerotic vascular disease resulting in widespread morbidity and mortality, particularly among older adults. One first-line therapy to improve symptoms, function, and clinical outcomes in PAD is supervised exercise therapy (SET), which is based primarily on a structured, start-and-stop walking protocol and is implemented in cardiac rehabilitation programs. SET is supported by a Class IA guideline for patients with symptomatic PAD; however, despite the effectiveness of SET and the 2017 CMS decision to cover SET for PAD, challenges of awareness, access, and implementation of SET persist. Recent efforts to address these challenges include digital health and hybrid approaches to SET that may minimize barriers to care by delivering SET in more innovative, flexible formats. Further study is needed to understand barriers, improve awareness, and implement SET in more equitable and accessible ways.

Cardiac Rehabilitation in Patients with Peripheral Artery Disease-A Literature Review in COVID-19 Era

Cardiac rehabilitation (CR) is an integral part of the management of various cardiovascular disease such as coronary artery disease (CAD), peripheral artery disease (PAD), or chronic heart failure (CHF), with proven morbidity and mortality benefits. This article aims to review and summarize the scientific literature related to cardiac rehabilitation programs for patients with PAD and how they were adapted during the COVID-19 pandemic. The implementation of CR programs has been problematic since the COVID-19 pandemic due to social distancing and work-related restrictions. One of the main challenges for physicians and health systems alike has been the management of PAD patients. COVID-19 predisposes to coagulation disorders that can lead to severe thrombotic events. Home-based walking exercises are more accessible and easier to accept than supervised exercise programs. Cycling or other forms of exercise are more entertaining or challenging alternatives to exercise therapy. Besides treadmill exercises, upper- and lower-extremity ergometry also has great functional benefits, especially regarding walking endurance. Supervised exercise therapy has a positive impact on both functional capacity and also on the quality of life of such patients. The most effective manner to acquire this seems to be by combining revascularization therapy and supervised exercise. Rehabilitation programs proved to be a mandatory part of the integrative approach in these cases, increasing quality of life, and decreasing stress levels, depression, and anxiety.

Trends in the Use of Cardiac Rehabilitation in Japan Between 2010 and 2017 - An Epidemiological Survey

Background: Despite the prognostic effectiveness of cardiac rehabilitation (CR) in patients with cardiovascular disease (CVD), it has been underutilized. Understanding the trend of dissemination of CR over the years would help provide a perspective of CR in Japan. Methods and Results: A retrospective epidemiological survey between fiscal years 2010 and 2017 was conducted using the diagnosis procedure combination database (a Japanese administrative database). Data on 2,046,302 patients with CVD from 1,632 hospitals were extracted. The proportion of CR-certified hospitals among hospitals treating patients with CVD increased from 31.6% in 2010 to 56.6% in 2017. Over the same period, the participation rate in inpatient CR (ICR) increased from 18.3% to 39.0%, but the participation rate in outpatient CR (OCR) remained low (from 1.4% to 2.5%). The CR participation rates varied widely according to the main disease group. Approximately 95% of ICR participants did not continue CR after discharge. Conclusions: The number of CR-certified hospitals increased from 2010 to 2017, leading to increased ICR participation across patients with CVD; however, OCR has remained extremely underutilized. Immediate action is urgently required to increase the use of OCR.

Rehabilitation of patients with peripheral arterial disease

Vascular rehabilitation is an essential and effective treatment of peripheral arterial obstructive disease (PAOD). It is recommended in the first line by the European and American scientific societies. The rehabilitation to the walk remains the basic treatment of the arteriopathy of the lower limbs. Different walking protocols can be proposed. For similar effectiveness, vascular rehabilitation consists of an outpatient or specialized institution management program based on a comprehensive approach involving all or many of the following techniques: relaxation, active analytical exercises, gait rehabilitation, exercise re-entry, physical activities adapted to the patient's daily life and illness, respiratory physiotherapy, therapeutic education of the patient, smoking cessation aid. Vascular rehabilitation of arteritis requires a variety of skills but still faces a clear lack of suitable structures; it remains poorly prescribed and poorly known by usual prescribers (general practitioner, vascular surgeon).

A Systematic Review of Exercise Prescription in Patients with Intermittent Claudication: Does Pain Matter?

BACKGROUND

Current guidelines for intermittent claudication advocate exercise at moderate to maximal claudication pain. However, adherence rates to supervised exercise programmes (SEP) remain poor and claudication pain is a contributing factor. Limited evidence suggests that moderate or pain-free exercise may be just as beneficial and may be better tolerated. However, it remains unclear what 'level' of claudication pain is optimal for improving functional outcomes. We therefore conducted a systematic review to synthesise the evidence for exercise prescribed at different levels of claudication pain.

METHODS

The CENTRAL, MEDLINE, Embase and CINAHL databases were searched up to October 2020. Randomized controlled trials (RCTs) that directly compared at least 2 different intensities of claudication pain were included. Outcome measures included walking performance, adherence, quality of life and vascular function.

RESULTS

Of 1,543 search results, 2 studies were included. Maximal walking distance improved by 100-128% in the moderate-pain SEP groups, and by 77-90% in the pain-free SEP groups. Importantly, there were no significant differences between the moderate-pain and pain-free SEP groups in either study for improvements in walking performance, though comparison to a maximal-pain SEP group was not made.

CONCLUSIONS

The efficacy of SEPs for patients with intermittent claudication is irrefutable, though there is no consensus on the optimal level of pain. Therefore, adequately powered RCTs are required to compare the effect of pain-free SEPs, moderate-pain SEPs and maximal-pain SEPs on functional outcomes. (PROSPERO ID: CRD42020213684).

Are Vascular Parameters Associated with Walking Impairment in Patients with Claudication?

BACKGROUND

The mechanisms underlying functional impairments in symptomatic PAD patients are controversial and poorly understood. Endothelial dysfunction and arterial stiffness have been proposed as potential mechanisms related to functional impairment in symptomatic PAD patients, however, more studies are needed to confirm these associations.

OBJECTIVE

To analyze the association between vascular function and walking impairment in patients with peripheral arterial disease (PAD) and symptoms of claudication.

METHODS

This was a cross-sectional study that included 68 patients with symptomatic PAD. All patients underwent an objective (Six-minute walk test [6MWT], 4-meter walk test) and a subjective (Walking Impairment Questionnaire [WIQ]) measurement of walking impairment. Vascular parameters measured were pulse-wave velocity (PWV) and flow-mediated dilation (FMD). Multiple linear regression was performed to investigate the association among walking impairment variables with vascular function parameters.

RESULTS

No significant associations between the claudication onset distance (PWV: b=.060, P = 0.842; FMD: b=-.192, P = 0.456), 6MWT (PWV: b=.007, P = 0..975; FMD: b=.090, P = 0.725), WIQ distance (PWV: b=.337, P = 0.117; FMD: b=-.025, P = 0.895) WIQ speed (PWV: b=.320, P = 0.181; FMD: b=-.028, P = 0.497), WIQ stairs (PWV: b=.256, P = 0.204; FMD: b=-.228, P = 0.230), 4-meter usual walk (PWV: b=-.421, P = 0.107; FMD: b=-.338, P = 0.112), 4-meter fast walk (PWV: b=-.496, P = 0.063; FMD: b=-.371, P = 0.086) and vascular function were found.

CONCLUSIONS

In symptomatic PAD patients, vascular function is not associated to walking impairment, even when adjusting for comorbid conditions and diabetes.

Pharmacological management of obstructive peripheral arterial disease: two case reports

INTRODUCTION

Peripheral artery disease (PAD), also abbreviated as LEAD or lower extremity artery disease, is an important predictor of cardiovascular morbidity and mortality. Rivaroxaban, a selective direct factor Xa inhibitor, is proposed as an additional pharmacologic option for managing this disease.

CASES

Two patients presented with PAD and high-risk comorbidities. The first case showed how the evaluation of the cardiovascular risk guided the therapeutic management of the patient. The second case was about a patient diagnosed with LEAD who experienced worsening from exertional ischemia towards critical ischemia requiring amputation despite distal revascularization, and parenteral vasodilator therapy to relieve pain. This case suggested a comprehensive care management approach, adapted to PAD progression stages.

CONCLUSION

The PAD management consists nowadays of optimizing the management of cardiovascular risk factors and disease progression. Diagnosis, treatment, monitoring and patient education should be handled by a vascular specialist in a specialized care unit.

Effects of bradykinin on voltage-gated KV 4 channels in muscle dorsal root ganglion neurons of rats with experimental peripheral artery disease

KEY POINTS

During exercise, bradykinin (BK), a muscle metabolite in ischaemic muscles, exaggerates autonomic responses to activation of muscle afferent nerves in peripheral artery disease (PAD). We examined whether BK inhibits activity of KV 4 channels in muscle afferent neurons of PAD rats induced by femoral artery occlusion. We demonstrated that: 1) femoral occlusion attenuates KV 4 currents in dorsal root ganglion (DRG) neurons innervating the hindlimb muscles and decreases the threshold of action potential firing; 2) BK has a greater inhibitory effect on KV 4 currents in muscle DRG neurons of PAD rats; and 3) expression of KV 4.3 is downregulated in DRGs of PAD rats and inhibition of KV 4.3 significantly decreases activity of KV 4 currents in muscle DRG neurons. Femoral artery occlusion-induced limb ischaemia and/or ischaemia-induced metabolites (i.e. BK) inhibit activity of KV 4 channels in muscle afferent neurons and this is likely involved in the exaggerated exercise pressor reflex in PAD.

ABSTRACT

Muscle afferent nerve-activated reflex sympathetic nervous and blood pressure responses are exaggerated during exercise in patients with peripheral artery diseases (PAD) and in PAD rats induced by femoral artery occlusion. However, the precise signalling pathways and molecular mediators responsible for these abnormal autonomic responses in PAD are poorly understood. A-type voltage-gated K+ (KV ) channels are quintessential regulators of cellular excitability in the various tissues. Among KV channels, KV 4 (i.e. KV 4.1 and KV 4.3) in primary sensory neurons mainly participate in physiological functions in regulation of mechanical and chemical sensation. However, little is known about the role of KV 4 in regulating neuronal activity in muscle afferent neurons of PAD. In addition, bradykinin (BK) is considered as a muscle metabolite contributing to the exaggerated exercise pressor reflex in PAD rats with femoral artery occlusion. Our data demonstrated that: 1) KV 4 currents are attenuated in dorsal root ganglion (DRG) neurons innervating the hindlimb muscles of PAD rats, along with a decreasing threshold of action potential firing; 2) KV 4 currents are inhibited by application of BK onto muscle DRG neurons of PAD rats to a greater degree; and 3) expression of KV 4.3 is downregulated in the DRGs of PAD rats and KV 4.3 channel is a major contributor to the activity of KV 4 currents in muscle DRG neurons. In conclusion, data suggest that femoral artery occlusion-induced limb ischaemia and/or ischaemia-induced metabolites (i.e. BK) inhibit the activity of KV 4 channels in muscle afferent neurons likely leading to the exaggerated exercise pressor reflex observed in PAD.

Phytochemicals as Therapeutic Interventions in Peripheral Artery Disease

Peripheral artery disease (PAD) affects over 200 million people worldwide, resulting in significant morbidity and mortality, yet treatment options remain limited. Among the manifestations of PAD is a severe functional disability and decline, which is thought to be the result of different pathophysiological mechanisms including oxidative stress, skeletal muscle pathology, and reduced nitric oxide bioavailability. Thus, compounds that target these mechanisms may have a therapeutic effect on walking performance in PAD patients. Phytochemicals produced by plants have been widely studied for their potential health effects and role in various diseases including cardiovascular disease and cancer. In this review, we focus on PAD and discuss the evidence related to the clinical utility of different phytochemicals. We discuss phytochemical research in preclinical models of PAD, and we highlight the results of the available clinical trials that have assessed the effects of these compounds on PAD patient functional outcomes.

Re-amputation and survival following toe amputation: outcome data from a tertiary referral centre

PURPOSE

Toe amputation is a commonly performed procedure for irreversible foot sepsis. However, outcome and predictors of outcome are poorly understood. Our aim was to determine survival and rate of progression to further amputation following index toe amputation.

METHODS

Consecutive patients between 2010 and 2015 were included. Progression to further minor amputation, major amputation or death was recorded. Multivariable Cox regression analyses were undertaken to determine independent predictors of outcome and survival.

RESULTS

One hundred forty-six patients were included, with mean age of 65 years. Fifty-five (37.7%) patients underwent hallux amputation, while 91 (62.3%) underwent amputation of non-hallux digit(s). Following index toe amputation, 63 (43.2%) patients progressed to further minor or major ipsilateral amputation, median time to which was 36 months. Twenty-one patients (14.4%) progressed to major ipsilateral amputation. Patients undergoing index non-hallux amputation were significantly more likely to require further minor amputation (P = 0.050); however, the rate of major amputation between hallux (14.5%) and non-hallux (14.3%) groups was similar. Overall, 5-year ipsilateral amputation-free (iAFS) was 39.6 ± 4.1%, ipsilateral major amputation-free (iMAFS) was 55.9 ± 4.1% and overall survival (OS) was 64.3 ± 4.0% and did not differ between index amputation sites.

CONCLUSION

Almost half of patients undergoing toe amputation required further digital amputation. However, limb preservation rates are high, and a majority of patients are alive at 5-year follow-up. There was no significant difference in outcome between patients undergoing hallux and non-hallux primary procedures. Overall, increasing age remains the only independent predictor of iMAFS and OS.

Contemporary Medical Management of Peripheral Artery Disease

Peripheral artery disease (PAD) is a manifestation of systemic atherosclerosis. Modifiable risk factors including cigarette smoking, dyslipidemia, diabetes, poor diet quality, obesity, and physical inactivity, along with underlying genetic factors contribute to lower extremity atherosclerosis. Patients with PAD often have coexistent coronary or cerebrovascular disease, and increased likelihood of major adverse cardiovascular events, including myocardial infarction, stroke and cardiovascular death. Patients with PAD often have reduced walking capacity and are at risk of acute and chronic critical limb ischemia leading to major adverse limb events, such as peripheral revascularization or amputation. The presence of polyvascular disease identifies the highest risk patient group for major adverse cardiovascular events, and patients with prior critical limb ischemia, prior lower extremity revascularization, or amputation have a heightened risk of major adverse limb events. Medical therapies have demonstrated efficacy in reducing the risk of major adverse cardiovascular events and major adverse limb events, and improving function in patients with PAD by modulating key disease determining pathways including inflammation, vascular dysfunction, and metabolic disturbances. Treatment with guideline-recommended therapies, including smoking cessation, lipid lowering drugs, optimal glucose control, and antithrombotic medications lowers the incidence of major adverse cardiovascular events and major adverse limb events. Exercise training and cilostazol improve walking capacity. The heterogeneity of risk profile in patients with PAD supports a personalized approach, with consideration of treatment intensification in those at high risk of adverse events. This review highlights the medical therapies currently available to improve outcomes in patients with PAD.

"Should I stay or should I go now?" Recovery time effect on walking capacity in symptomatic peripheral artery disease

The objective of the study was to investigate the effect of recovery time on walking capacity (WC) throughout repeated maximal walking bouts in symptomatic lower-extremity peripheral artery disease (PAD). The effect of recovery time on WC (maximal walking time) was determined in 21 participants with PAD in three experimental conditions [recovery time from 0.5 to 9.5 min + a self-selected recovery time (SSRT)]: 1) 11 repeated sequences of two treadmill walking bouts (TW-ISO); 2) a single sequence of seven treadmill walking bouts (TW-CONS); 3) a single sequence of seven outdoor walking bouts (OW-CONS). Exercise transcutaneous oxygen pressure changes were continuously recorded as an indirect measure of ischemia. An individual recovery time (IRT) beyond which WC did not substantially increased was determined in participants with a logarithmic fit. At the group level, mixed models showed a significant effect (P < 0.001) of recovery time on WC restoration. At the participant level, strong logarithmic relationships were found (median significant R² ≥ 0.78). The median SSRT corresponded to a median work-to-rest ratio >1:1 (i.e., a lower recovery time in view of the corresponding previous walking time) and was related to unrecovered ischemia and a WC restoration level of <80%. A median work-to-rest ratio of ≤1:2 allowed full recovery of ischemia and full restoration of WC. The IRT ratio was between 1:1 and 1:2 and corresponded to the start of recovery from ischemia. Recovery time affects the restoration level of WC during repeated maximal walking bouts in symptomatic PAD. Meaningful variations in WC restoration were related to specific levels of work-to-rest ratios.NEW & NOTEWORTHY This study demonstrated that there is a significant and mostly logarithmic effect of recovery time on walking capacity in people with symptomatic PAD. This study revealed that a median work-to-rest ratio >1:1 leads to the resumption of walking with unrecovered ischemia and precludes the restoration of full walking capacity, whereas a work-to-rest ratio ≤1:2 allowed walking capacity to fully be restored.

Patients with Diabetes Complicated by Peripheral Artery Disease: the Current State of Knowledge on Physiotherapy Interventions

Diabetes mellitus (DM) is one of the major public health problems that account for morbidity, mortality, and disability worldwide. The presence of DM increases the risk of peripheral artery disease (PAD), as well as accelerates its course, making these patients more susceptible to ischemic events and impaired functional status. Unfortunately, alternative treatments for vascular complications in diabetes are poorly researched. Physiotherapy (kinesitherapy combined with different physical therapy agents) in individuals with DM and coexisting PAD may offer an important complementary therapy alternative. Early therapeutic measures can significantly improve patient outcomes, reduce cardiovascular risk, and improve daily life quality. The article provides an update on the current state of knowledge on physiotherapy interventions in the course of DM in patients with coexisting PAD.

Avoiding revascularization strategy versus revascularization with drug-coated balloon for the treatment of superficial femoral artery occlusive disease

OBJECTIVE

The aim of this study was to compare the efficacy, safety and treatment costs of superficial femoral artery revascularization (SFA) with drug-coated balloon(DCB) versus avoiding revascularization strategy for the treatment of symptomatic SFA disease.

METHODS

This retrospective single-center study reviewed 96 patients (113 limbs) with severe stenosis and occlusive SFA disease. All patients underwent either DCB(Group 1: n ​= ​55 limbs) or nonrevascularization (Group 2: n ​= ​58 limbs) between March 2015 and June 2019. The improvement of Rutherford class, walking impairment questionnaire score(WIQ), target limb reintervention, perioperative major adverse events, the catheterization laboratory cost and length of hospital stay were compared. The limb salvage and survival rates were calculated using the Kaplan-Meier method. Univariate and multivariate logistic regression analysis were performed to assess the association between factors and the improvement of Rutherford category at 12 months.

RESULTS

The median follow-up time of Groups 1 and 2 was 17 and 33 months, respectively. At 12 months, the Rutherford category significantly decreased in both groups (P ​< ​0.001), with no significant difference (79.7% vs. 64.3%, P ​= ​0.074). Furthermore, multivariate analysis showed that the selected therapeutic method was not an influential factor for the improvement of Rutherford class at 12 months. The WIQ overall score as well as three subscales scores (distance, speed and stair-climbing), the survival rate, limb salvage rate and the length of stay between the two groups were comparable. The perioperative adverse events rate and catheterization laboratory cost in Group 2 was significantly lower compared to Group 1 [(34253.69 ​± ​28172.87) yuan vs. (56936.76 ​± ​41278.36) yuan, P ​= ​0.001].

CONCLUSIONS

This study suggests that avoiding superficial femoral artery revascularization strategy has favorable efficacy and safety outcomes compared to combining revascularization with DCB in selected patients.

Sympathetic Nerve Control of Blood Pressure Response during Exercise in Peripheral Artery Disease and Current Application of Experimental Disease Models

In patients with peripheral artery disease (PAD), the blood supply directed to the lower limbs is reduced. This results in severe limb ischemia and thereby intermittent claudicating which is characterized by pain in lower limbs that occurs with walking and is relieved by rest. Of note, PAD can extremely affect the quality of living of patients and increase high risk of coronary and cerebral vascular accidents. However, effective treatments of PAD are still challenging in clinics. A number of reports have demonstrated the beneficial effects of supervised exercise on symptoms of PAD patients. This review will summarize results obtained from recent human and animal studies, which include the abnormalities in sympathetic control of blood pressure response during exercise in PAD, and rationality of animal models used for study human PAD. Nonetheless, additional in-depth studies are necessary to better explore the underlying mechanisms of the exaggerated responses of sympathetic nerve and blood pressure in PAD at molecular and cellular levels.

Effects of Postoperative Percutaneous Coronary Intervention, Pharmacologic Treatment, and Predisposing Factors on Clinical Outcomes in Patients With and Without Type 2 Diabetes Along With Critical Limb Ischemia

PURPOSE

Critical limb ischemia (CLI) has been identified as being connected to rates of cardiovascular mortality and lower extremity amputation (LEA). This prospective study investigated the effects of percutaneous coronary intervention (PCI), pharmacologic treatment, and predisposing factors on clinical outcomes in patients with and without type 2 diabetes mellitus (DM) along with CLI after endovascular intervention.

METHODS

249 consecutive patients with CLI (Fontaine stages III-IV) received pharmacologic treatment after successful endovascular intervention. Their primary patency rates of infrapopliteal lesions and cardiovascular and amputation events during a 36-month follow-up period were assessed.

FINDINGS

Patients with DM were more likely to be younger (P = 0.026); 50% (n = 63), 42.9% (n = 54), 52.4% (n = 66), and 77% (n = 97) of DM patients had arterial calcification, end-stage renal disease, diabetic neuropathy, and Fontaine stage IV (P < 0.001, P < 0.001, P < 0.001, and P = 0.019, respectively). The primary patency rates were 61%, 48.8%, and 42.3% at 12, 24, and 36 months, in the patients without DM (P = 0.034, P = 0.013, and P = 0.005). Patients with DM had higher risks of 36-month coronary artery disease, cerebrovascular accident, mortality, and LEA (P = 0.005, P = 0.042, P = 0.042, and P < 0.001). Patients with CLI receiving long-term cilostazol treatment had a better primary patency and amputation-free survival, and a lower risk of mortality at 36 months (P < 0.001, P < 0.001, and P = 0.001). Statin use was associated with 36-month amputation-free survival but not with primary patency (P = 0.032 and P = 0.088). Subgroup multivariate Cox analyses showed that primary patency was independently associated with long-term cilostazol treatment, PCI in the first postoperative year, and direct revascularization in the DM group, whereas in the control group, long-term cilostazol treatment was the main independent factor. The risk of amputation was independently associated with a high high-sensitivity chronic reactive protein level, diabetic neuropathy, sole use of an oral hypoglycemic agent, and lack of supervised exercise.

IMPLICATIONS

Long-term cilostazol treatment, aggressive management of dyslipidemia, and meticulous assessment and prevention of postoperative unstable coronary artery disease should be considered in CLI patients with and without DM to maximize clinical outcomes. PCI in the first postoperative year may be a predisposing factor for patency failure in patients with CLI, especially those with DM. A large-scale prospective randomized trial should be conducted to confirm these findings (TVGH IRB No. 2013-08-020B).

Peripheral Artery Disease in Diabetes Mellitus: Focus on Novel Treatment Options

Diabetes mellitus (DM) and peripheral artery disease (PAD) are two clinical entities closely associated. They share many pathophysiological pathways such as inflammation, endothelial dysfunction, oxidative stress and pro-coagulative unbalance. Emerging data focusing on agents targeting these pathways may be promising. Moreover, due to the increased cardiovascular risk, there is a growing interest in cardiovascular and "pleiotropic" effects of novel glucose lowering drugs. This review summarizes the main clinical features of PAD in patients, the diagnostic process and current medical/interventional approaches, ranging from "classical treatment" to novel agents.

Effects of REDOX in Regulating and Treatment of Metabolic and Inflammatory Cardiovascular Diseases

Reduction oxidation (REDOX) reaction is crucial in life activities, and its dynamic balance is regulated by ROS. Reactive oxygen species (ROS) is associated with a variety of metabolic diseases involving in multiple cellular signalling in pathologic and physiological signal transduction. ROS are the by-products of numerous enzymatic reactions in various cell compartments, including the cytoplasm, cell membrane, endoplasmic reticulum (ER), mitochondria, and peroxisome. ROS signalling is not only involved in normal physiological processes but also causes metabolic dysfunction and maladaptive responses to inflammatory signals, which depends on the cell type or tissue environment. Excess oxidants are able to alter the normal structure and function of DNA, lipids, and proteins, leading to mutations or oxidative damage. Therefore, excessive oxidative stress is usually regarded as the cause of various pathological conditions, such as cancer, neurodegeneration, cardiovascular diseases (CVDs), diabetes, and kidney diseases. Currently, it has been possible to detect diabetes and other cardiac diseases by detecting derivatives accompanied by oxidative stress in vivo as biomarkers, but there is no effective method to treat these diseases. In consequence, it is essential for us to seek new therapy targeting these diseases through understanding the role of ROS signalling in regulating metabolic activity, inflammatory activation, and cardiac diseases related to metabolic dysfunction. In this review, we summarize the current literature on REDOX and its role in the regulation of cardiac metabolism and inflammation, focusing on ROS, local REDOX signalling pathways, and other mechanisms.

Differences in Physical Activity between Patients with Peripheral Artery Disease and Healthy Subjects

Objectives

Peripheral artery disease (PAD) is a significant prognostic marker of poor long-term survival due to limited physical activity associated with various functional problems, such as intermittent claudication. A physically active lifestyle has the potential to modify peripheral artery risk factors and promote general health. While low daily physical activity levels have been recognized in the population of PAD, the exact level has yet to be quantified due to lack of research. The aim of the present study was to compare physical activity level (PAL) and time spent at activities of different intensity levels between patients with PAD and healthy individuals. The study subjects were 10 patients with PAD and 10 age-matched healthy control subjects. We measured the time spent at light, moderate, or vigorous physical activity using triaxial accelerometer and calculated PAL. Intermittent claudication onset distance and maximum walking distance were defined as the distance walked at which the subject first reported leg pain and the distance at which the subject was unable to continue walking because of leg pain, respectively.

Results

Our results showed (i) lower PAL in patients with PAD compared with the controls; (ii) while there was no significant difference in the high-intensity activity between the two groups, the light- and moderate-intensity activities of the PAD group were significantly lower than the controls, the time spent at moderate-intensity activity was approximately 50% less; and (iii) among patients with PAD, low PAL did not correlate directly with intermittent claudication.

Conclusions

PAD patients limit the amount of their physical activity, especially light and moderate intensities. Our study highlights the importance of spending more time walking in daily life.

Exercise training for intermittent claudication: a narrative review and summary of guidelines for practitioners

Peripheral artery disease (PAD) is caused by atherosclerotic narrowing of the arteries supplying the lower limbs often resulting in intermittent claudication, evident as pain or cramping while walking. Supervised exercise training elicits clinically meaningful benefits in walking ability and quality of life. Walking is the modality of exercise with the strongest evidence and is recommended in several national and international guidelines. Alternate forms of exercise such as upper- or lower-body cycling may be used, if required by certain patients, although there is less evidence for these types of programmes. The evidence for progressive resistance training is growing and patients can also engage in strength-based training alongside a walking programme. For those unable to attend a supervised class (strongest evidence), home-based or 'self-facilitated' exercise programmes are known to improve walking distance when compared to simple advice. All exercise programmes, independent of the mode of delivery, should be progressive and individually prescribed where possible, considering disease severity, comorbidities and initial exercise capacity. All patients should aim to accumulate at least 30 min of aerobic activity, at least three times a week, for at least 3 months, ideally in the form of walking exercise to near-maximal claudication pain.