Supervised exercise versus primary stenting for claudication resulting from aortoiliac peripheral artery disease: six-month outcomes from the claudication: exercise versus endoluminal revascularization (CLEVER) study

Catheter based interventions for lower extremity peripheral artery disease

The field of peripheral arterial intervention has exploded over the past 20 years. Current knowledge includes a growing evidence base for treatment as well as a myriad of new interventional approaches to complex disease. This review seeks to outline the current state of the art for interventional approaches to lower extremity peripheral arterial disease.

Critical appraisal of evidence on bypass surgery versus endovascular treatment for intermittent claudication: a systematic review and meta-analysis

INTRODUCTION

Intermittent claudication (IC) stage of peripheral artery disease (PAD) is associated with significant impairment of quality of life. In the subset of patients with disabling IC refractory to best medical treatment (BMT), revascularization procedures may be considered. However, evidence comparing open revascularization surgery, endovascular treatment and BMT focussing on the impact on quality of life is very sparse. We aim to review clinical, anatomical and hemodynamic outcomes after bypass surgery compared to BMT and/or endovascular treatment in IC patients.

EVIDENCE ACQUISITION

We systematically reviewed controlled trials and comparative cohort studies assessing quality of life, walking performance, clinical/symptomatic improvement, symptom recurrence, patency rates, ankle-brachial index (ABI) improvement and adverse events after bypass surgery versus endovascular treatment/BMT in IC patients.

EVIDENCE SYNTHESIS

Eleven studies involving 16,608 patients were included. Compared to BMT, bypass surgery was associated with a significantly greater improvement on Short-Form 36 (SF-36) physical functioning score (mean difference (MD), -14.0; 95% confidence interval (CI), -21.2 to -6.8), Walking Impairment Questionnaire (WIQ) walking distance score (MD, -0.23; 95% CI, -0.29 to -0.16) and SF-36 bodily pain score (MD, -13.0; 95% CI, -20.2 to -5.8). There were no significant differences between bypass and endovascular treatment regarding the three scores. Bypass surgery presented better primary patency rates at 1 (odds ratio (OR), 0.47; 95% CI, 0.29 to 0.76) and 5 years (OR, 0.44; 95% CI, 0.34 to 0.57) and better ABI improvement (MD, -0.07; 95% CI, -0.12 to -0.03) when compared to endovascular treatment. There were no statistically significant differences between bypass and endovascular patients regarding secondary patency rates, 30-day mortality and major amputation.

CONCLUSIONS

Lower limb revascularization may be beneficial in patients with disabling and refractory IC when the primary goal is to improve quality of life and walking capacity. Bypass surgery is associated to better symptomatic status, long-term primary patency and ABI improvement when compared to endovascular surgery, especially in anatomically extensive disease. Further studies addressing patient-reported outcomes and including a BMT group are paramount for more robust evidence on IC treatment and, consequently, better decision making.

Racial disparities in surgical management and outcomes of acute limb ischemia in the United States

Background

Although significant racial disparities in the surgical management of lower extremity critical limb threatening ischemia have been previously reported, data on disparities in lower extremity acute limb ischemia are lacking.

Methods

The 2012–2018 National Inpatient Sample was queried for all adult hospitalizations for acute limb ischemia (N = 225,180). Hospital-specific observed-to-expected rates of major lower extremity amputation were tabulated. Multivariable logistic and linear models were developed to assess the impact of race on amputation and revascularization.

Results

Nonwhite race was associated with significantly increased odds of overall (adjusted odds ratio: 1.16, 95% confidence interval 1.06–1.28) and primary (adjusted odds ratio: 1.34, 95% confidence interval 1.17–1.53) major amputation, decreased odds of revascularization (adjusted odds ratio 0.79, 95% confidence interval 0.73–0.85), but decreased in-hospital mortality (adjusted odds ratio: 0.86, 95% confidence interval 0.74–0.99). The nonwhite group incurred increased adjusted index hospitalization costs (β: +$4,810, 95% confidence interval 3,280-6,350), length of stay (β: + 1.09 days, 95% confidence interval 0.70–1.48), and nonhome discharge (adjusted odds ratio: 1.15, 95% confidence interval 1.06–1.26).

Conclusion

Significant racial disparities exist in the management of and outcomes of lower extremity acute limb ischemia despite correction for variations in hospital amputation practices and other relevant hospital and patient characteristics. Whether the etiology lies primarily in patient, institution, or healthcare provider–specific factors has not yet been determined. Further studies of race-based disparities in management and outcomes of acute limb ischemia are warranted to provide effective and equitable care to all.

No benefit of vorapaxar on walking performance in patients with intermittent claudication

Background: The effect of pharmacologic agents in improving walking and quality of life measures in patients with intermittent claudication (IC) is variable. The objective of this study was to investigate the effect of the novel antithrombotic vorapaxar on symptom status in patients with IC. Methods: The study was a multicenter, randomized, placebo-controlled trial wherein patients with IC were treated with either vorapaxar or placebo in addition to a home exercise program for 6 months. Walking performance and quality of life were assessed by graded treadmill test (GTT) and 12-Item Short-Form Survey (SF-12), respectively, at baseline and at 6 months. A total of 102 subjects were randomized across 12 centers. Results: Of the subjects randomized, 66 completed all study assessments and comprised the dataset that was analyzed. After 6 months, there was no significant difference between the vorapaxar and placebo groups in walking performance, as reflected by the GTT, or in quality of life, as reflected by the SF-12. There were no severe bleeding events in either group. Conclusion: This study found no benefit of vorapaxar in patients with IC and reiterates the need for future drug therapy studies that expand the benefits of supervised exercise therapy in patients with IC. ClinicalTrials.gov Identifier: NCT02660866.

Lower Extremity Peripheral Artery Disease: Contemporary Epidemiology, Management Gaps, and Future Directions: A Scientific Statement From the American Heart Association

Lower extremity peripheral artery disease (PAD) affects >230 million adults worldwide and is associated with increased risk of various adverse clinical outcomes (other cardiovascular diseases such as coronary heart disease and stroke and leg outcomes such as amputation). Despite its prevalence and clinical importance, PAD has been historically underappreciated by health care professionals and patients. This underappreciation seems multifactorial (eg, limited availability of the first-line diagnostic test, the ankle-brachial index, in clinics; incorrect perceptions that a leg vascular disease is not fatal and that the diagnosis of PAD would not necessarily change clinical practice). In the past several years, a body of evidence has indicated that these perceptions are incorrect. Several studies have consistently demonstrated that many patients with PAD are not receiving evidence-based therapies. Thus, this scientific statement provides an update for health care professionals regarding contemporary epidemiology (eg, prevalence, temporal trends, risk factors, and complications) of PAD, the present status of diagnosis (physiological tests and imaging modalities), and the major gaps in the management of PAD (eg, medications, exercise therapy, and revascularization). The statement also lists key gaps in research, clinical practice, and implementation related to PAD. Orchestrated efforts among different parties (eg, health care providers, researchers, expert organizations, and health care organizations) will be needed to increase the awareness and understanding of PAD and improve the diagnostic approaches, management, and prognosis of PAD.

The Role of Mitochondrial Function in Peripheral Arterial Disease: Insights from Translational Studies

Recent evidence demonstrates an involvement of impaired mitochondrial function in peripheral arterial disease (PAD) development. Specific impairments have been assessed by different methodological in-vivo (near-infrared spectroscopy, ³¹P magnetic resonance spectroscopy), as well as in-vitro approaches (Western blotting of mitochondrial proteins and enzymes, assays of mitochondrial function and content). While effects differ with regard to disease severity, chronic malperfusion impacts subcellular energy homeostasis, and repeating cycles of ischemia and reperfusion contribute to PAD disease progression by increasing mitochondrial reactive oxygen species production and impairing mitochondrial function. With the leading clinical symptom of decreased walking capacity due to intermittent claudication, PAD patients suffer from a subsequent reduction of quality of life. Different treatment modalities, such as physical activity and revascularization procedures, can aid mitochondrial recovery. While the relevance of these modalities for mitochondrial functional recovery is still a matter of debate, recent research indicates the importance of revascularization procedures, with increased physical activity levels being a subordinate contributor, at least during mild stages of PAD. With an additional focus on the role of revascularization procedures on mitochondria and the identification of suitable mitochondrial markers in PAD, this review aims to critically evaluate the relevance of mitochondrial function in PAD development and progression.

Real World Practice Deviation from Nationwide Guidelines in Patients with Intermittent Claudication

OBJECTIVE

Patients with intermittent claudication (IC) are initially treated with supervised exercise therapy (SET), as advised by national and international guidelines. Dutch health insurance companies and the Dutch National Health Care Institute suggested an 87% compliance rate with these guidelines in the Netherlands in 2017 and judged this to be undesirably low. The aim of this study was to evaluate compliance with IC guidelines and to elaborate on the reasons for deviating from them (practice variation) in a large teaching hospital.

METHODS

A retrospective single centre cohort study was conducted at a large teaching hospital in the Netherlands. In total, 420 patients with newly diagnosed IC between 1 January 2017 and 31 December 2018 were analysed. Data included risk profiles and prescribed therapies.

RESULTS

For all 420 included patients, the compliance rate with the guidelines for SET was 80.5%. The rate of adequately motivated and defensible practice variation was 15.7%; the rate of unjustified practice variation was 3.8%. Meaningful care was seen in 96.2% of cases.

CONCLUSION

Deviation from IC guidelines was found in 19.5% of patients. Almost three quarters of this deviation can be explained by the decision to provide personalised, meaningful care.

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.

The effect of revascularization on recovery of mitochondrial respiration in peripheral artery disease: a case control study

Background

Peripheral arterial disease (PAD) is accompanied by myopathy characterized by mitochondrial dysfunction. The aim of this experimental study was to investigate the effect of revascularization procedures on mitochondrial function in ischemic and non-ischemic muscle.

Methods

Muscle biopsies from patients with symptomatic stage IIB/III PAD caused by isolated pathologies of the superficial femoral artery were obtained from muscle regions within the chronic ischemic muscle (gastrocnemius) and from non-ischemic muscle (vastus lateralis) before and 6 weeks after invasive revascularization. High-resolution respirometry was used to investigate mitochondrial function and results were normalized to citrate synthase activity (CSA). Results are given in absolute values and fold over basal (FOB).

Results

Respiratory states (OXPHOS (P) and electron transfer (E) capacity) normalized to CSA decreased while CSA was increased in chronic ischemic muscle after revascularization. There were no changes in in non-ischemic muscle. The FOB of chronic ischemic muscle was significantly higher for CSA (chronic ischemic 1.37 (IQR 1.10–1.64) vs. non-ischemic 0.93 (IQR 0.69–1.16) p = 0.020) and significantly lower for respiratory states normalized to CSA when compared to the non-ischemic muscle (P per CSA chronic ischemic 0.64 (IQR 0.46–0.82) vs non-ischemic 1.16 (IQR 0.77–1.54) p = 0.011; E per CSA chronic ischemic 0.61 (IQR 0.47–0.76) vs. non-ischemic 1.02 (IQR 0.64–1.40) p = 0.010).

Conclusions

Regeneration of mitochondrial content and function following revascularization procedures only occur in muscle regions affected by malperfusion. This indicates that the restoration of blood and oxygen supply are important mediators aiding mitochondrial recovery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02908-0.

Effects of supervised exercise therapy on blood pressure and heart rate during exercise, and associations with improved walking performance in peripheral artery disease: Results of a randomized clinical trial

OBJECTIVE

Supervised exercise therapy (SET) improves walking ability in people with peripheral artery disease (PAD). However, the effects of SET on cardiovascular health in PAD remain unclear. Using data from a randomized clinical trial, this post hoc analyses investigated the effects of a 6-month SET intervention, compared with a control group, on changes in blood pressure (BP) and heart rate (HR) during a graded treadmill exercise test in people with PAD.

METHODS

We randomized 210 participants with PAD to either SET (3× weekly) or control (1× weekly health lectures) for 6 months. A graded treadmill exercise test, 6-minute walk test, and Walking Impairment Questionnaire were completed at baseline and the 6-month follow-up. BP and HR were measured at the end of each 2-minute stage of the graded treadmill exercise test. Mixed effects regression models compared the overall mean 6-month change in systolic BP, diastolic BP, pulse pressure (PP), and HR during the first 5 stages of the graded treadmill exercise test between groups.

RESULTS

Of the 210 randomized participants with PAD, 176 (67 ± 9 years; 72 [41%] female, 115 [65%] Black) completed the graded treadmill exercise test at baseline and the 6-month follow-up. Compared with the control group at the 6-month follow-up, SET significantly decreased overall mean systolic BP (-12 mm Hg; P < .001), PP (-9 mm Hg; P < .001), and HR (-7 b/min; P < .01) during a graded treadmill exercise test but not diastolic BP. Among participants randomized to SET, a greater decrease in systolic BP, PP, and HR during a graded treadmill exercise test was significantly associated with a greater improvement in 6-minute walk distance (systolic BP, r = -0.19 [P = .03] and PP, r = -0.23 [P < .01]; and HR, r = -0.21 [P < .01]) and with maximal treadmill walking distance (systolic BP, r = -0.21 [P < .01] and PP, r = -0.17 [P = .03]) at the 6-month follow-up. A greater decrease in the HR during a graded treadmill exercise test was significantly associated with a better WIQ distance score (r = -0.27; P = .03) at the 6-month follow-up.

CONCLUSIONS

In people with PAD, compared with a control group, SET improved cardiovascular health, measured by changes in BP and HR during exercise. The degree of improvement in cardiovascular health correlated with the degree of improvement in walking performance in people with PAD. NCT: 01408901.

Perceived Versus Objective Change in Walking Ability in Peripheral Artery Disease: Results from 3 Randomized Clinical Trials of Exercise Therapy

Background

In people with lower‐extremity peripheral artery disease, the effects of exercise on patient‐reported outcomes remain unclear.

Methods and Results

Four hundred four people with peripheral artery disease in 3 clinical trials were randomized to exercise (N=205) or a control group (N=199) and completed the 6‐minute walk and the Walking Impairment Questionnaire distance score (score 0–100, 100=best) at baseline and 6‐month follow‐up. Compared with the control group, exercise improved 6‐minute walk distance by +39.8 m (95% CI, 26.8–52.8, P<0.001) and the Walking Impairment Questionnaire distance score by +7.3 (95% CI, 2.4–12.1, P=0.003). In all, 2828 individual Walking Impairment Questionnaire distance score questions were completed at baseline and follow‐up. Among participants who perceived no change in ability to walk 1 or more distances between baseline and follow‐up, 6‐minute walk improved in the exercise group and declined in the control group (+26.8 versus −6.5 m, P<0.001). Among participants who perceived that their walking ability worsened for 1 or more distances between baseline and follow‐up, the 6‐minute walk improved in the exercise group and declined in the control group (+18.4 versus –27.3 m, P<0.001). Among participants who reported worsening calf symptoms at follow‐up, the exercise group improved and the control group declined (+28.9 versus −12.5 m, P<0.01).

Conclusions

In 3 randomized trials, exercise significantly improved the 6‐minute walk distance in people with peripheral artery disease, but many participants randomized to exercise reported no change or decline in walking ability. These findings suggest a significant discrepancy in objectively measured walking improvement relative to perceived walking improvement in people with peripheral artery disease.

Registration Information

clinicaltrials.gov. Identifiers: NCT 00106327, NCT 01408901.

Establishing Thresholds for Minimal Clinically Important Differences for the Peripheral Artery Disease Questionnaire

BACKGROUND

Understanding minimum clinically important differences (MCID) in patient-reported outcomes is essential in interpreting the magnitude of changes in these measures. No MCID from patients' perspectives has ever been published for peripheral artery disease-specific health status assessment tools. The Peripheral Artery Questionnaire (PAQ) is a commonly used, validated peripheral artery disease-specific health status instrument for which we sought to prospectively establish its MCID from patients' perspectives.

METHODS AND RESULTS

Patients presenting to vascular clinics with new or worsened claudication in the US cohort of the PORTRAIT (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) registry who completed baseline and follow-up PAQ assessments along with the Global Assessment of Functioning scale were included. Mean change in PAQ summary scores from 3- to 6-month follow-up was calculated according to Global Assessment of Functioning category. MCID was defined as the mean difference in scores between those with small improvement or deterioration and those with no change. Multivariable linear regression was used to provide an MCID estimate after adjusting for patients' 3-month PAQ score. Of the 483 patients who completed the Global Assessment of Functioning score at 6 months and who had available 3- and 6-month PAQ assessments, the mean age was 69 years, 42% were female, and 71% were White. The MCIDs for PAQ summary scale improvement and worsening were 8.7 (2.9-14.5) and -11.0 (-18.6 to -3.3), respectively. After multivariable adjustment, these were 8.9 (3.0-14.8) and -11.2 (-18.2 to -4.2), respectively. There was no significant interaction between treatment (invasive versus noninvasive) and Global Assessment of Functioning response (P=0.75).

CONCLUSIONS

In patients with new or worsened claudication, a 10-point change in PAQ summary score represents an MCID. This estimate needs external validation and may inform the interpretation of PAQ scores when used as outcomes in clinical trials or in routine clinical care. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01419080.

A systematic review of exercise testing in patients with intermittent claudication: A focus on test standardisation and reporting quality in randomised controlled trials of exercise interventions

A systematic review was conducted to identify the range of terminology used in studies to describe maximum walking distance and the exercise testing protocols, and testing modalities used to measure it in patients with intermittent claudication. A secondary aim was to assess the implementation and reporting of the exercise testing protocols. CINAHL, Medline, EMBASE and Cochrane CENTRAL databases were searched. Randomised controlled trials whereby patients with intermittent claudication were randomised to an exercise intervention were included. The terminology used to describe maximal walking distance was recorded, as was the modality and protocol used to measure it. The implementation and reporting quality was also assessed using pre-specified criteria. Sixty-four trials were included in this review. Maximal walking distance was reported using fourteen different terminologies. Twenty-two different treadmill protocols and three different corridor tests were employed to assess maximal walking distance. No single trial satisfied all the implementation and reporting criteria for an exercise testing protocol. Evidence shows that between-study interpretation is difficult given the heterogenous nature of the exercise testing protocols, test endpoints and terminology used to describe maximal walking distance. This is further compounded by poor test reporting and implementation across studies. Comprehensive guidelines need to be provided to enable a standardised approach to exercise testing in patients with intermittent claudication.

Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2021 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors related to cardiovascular disease.

RESULTS

Each of the 27 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Aorto-iliac peripheral artery disease

Aorto-iliac disease is a common manifestation of atherosclerosis. Individuals with this condition are at heightened cardiovascular risk, and may have limb symptoms ranging from claudication to limb-threatening ischemia. A regimen of medical therapy, risk factor modification, and exercise is first line therapy. Revascularization is reserved for individuals with lifestyle-limiting claudication despite conservative therapy and in those with chronic limb-threatening ischemia. Multiple endovascular therapies are now available that enable even the most complex aorto-iliac lesions to be approached and treated with safe and durable results.

Physical Activity After Treatment for Symptomatic Peripheral Artery Disease

The association of invasive versus noninvasive treatment and physical activity level in patients with claudication remains unclear. Participants with claudication were enrolled from US vascular clinics. Treatment was categorized as invasive (surgical or endovascular treatment <3 months of initial visit) versus noninvasive. Self-reported leisure time (LTPA) and work related physical activity (WRPA) (sedentary, mild, moderate/strenuous), and health status (peripheral artery questionnaire summary score [PAQ SS]) was measured at baseline and 12 months. Change in PA was also categorized as increased, decreased, persistent sedentary [reference] and persistent active based on activity status at baseline and 12 months. Multivariable logistic regression assessed the association of treatment with 12-month LTPA and WRPA. Multivariable linear regression examined the association between 12-month change in PA with a 12-month change in PAQ. A total of 196of 656 patients (29.9%) underwent invasive treatment. There was no association between treatment and 12-month LTPA (p = 0.77) or WRPA (p = 0.26). Compared with being persistently sedentary, increased LTPA was associated with increased PAQ SS (OR 11.1 95% CI [4.4 to 17.7], p <0.01). In conclusion, there was no association between invasive treatment and physical activity at follow up despite a greater health status change in the invasive group. As increased physical activity was associated with more health status gains than remaining sedentary, additional ways to improve physical activity levels could potentially improve PAD outcomes.

Endovascular interventions for claudication do not meet minimum standards for the Society for Vascular Surgery efficacy guidelines

OBJECTIVE

Because the treatment of intermittent claudication (IC) is elective, good short- and long-term outcomes are imperative. The objective of the present study was to examine the outcomes of endovascular management of IC reported in the Vascular Quality Initiative and compare them with the Society for Vascular Surgery guidelines for IC treatment to determine whether real-world results are within the guidelines.

METHODS

Patients undergoing peripheral vascular intervention for IC from 2004 to 2017 with complete data and >9 month follow-up were included. The primary outcome measures were IC recurrence and repeat procedures performed ≤2 years after the initial treatment.

RESULTS

A total of 16,152 patients met the inclusion criteria, with a mean age of 66 years. Of the 16,152 patients, 61% were men, 45% were current smokers, and 28% had been discharged without antiplatelet or statin medication. Adjusted analyses revealed that treatment of more than two arteries was associated with a shorter time to IC recurrence (hazard ratio [HR], 1.19; 95% confidence interval [CI], 1.09-1.31) and a shorter time to repeat procedures (HR, 1.25; 95% CI, 1.09-1.45). The use of atherectomy was also associated with a shorter time to IC recurrence (HR, 1.29; 95% CI, 1.08-1.33) and a shorter time to repeat procedures (HR, 1.31; 95% CI, 1.13-1.52). Discharge with antiplatelet and statin medications was associated with a longer time to IC recurrence (HR, 0.84; 95% CI, 0.78-0.91) and a longer time to repeat procedures (HR, 0.77; 95% CI, 0.69-0.87). Life-table analysis at 2 years revealed that only 32% of patients were free from IC recurrence, although 76% had not undergone repeat procedures. Stratified by anatomic treatment level, 37% of isolated aortoiliac interventions, 22% of aortoiliac and femoropopliteal interventions, 30% of isolated femoropopliteal interventions, and 20% of femoropopliteal and tibial interventions had remained free from IC recurrence at 2 years.

CONCLUSIONS

Most patients treated with an endovascular approach to IC did not meet the Society for Vascular Surgery guidelines for long-term freedom from recurrent symptoms of >50% at 2 years. Many lacked preprocedure optimization of medical management. The use of atherectomy and treatment of more than two arteries were associated with poor outcomes after peripheral vascular intervention for IC, because only 32% of these patients were free from recurrent symptoms at 2 years. Even when risk factor modification is optimized before the procedure, vascular specialists should be aware of the association between atherectomy and multivessel interventions with poorer long-term outcomes and counsel patients appropriately before intervention.

Association of Diabetes Mellitus With Health Status Outcomes in Patients With Peripheral Artery Disease: Insights From the PORTRAIT Registry

Background

Patients with peripheral artery disease (PAD) and coexisting diabetes mellitus (DM) have greater PAD progression and adverse limb events. Our aim was to study whether PAD‐specific health status differs by DM.

Methods and Results

The PORTRAIT (Patient‐Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) trial is a 16‐center international registry that includes patients with recent exacerbations or new‐onset symptomatic PAD presenting to specialty clinics. We assessed PAD‐specific health status initially and at 3, 6, and 12 months (Peripheral Artery Questionnaire [PAQ]). We used hierarchical, multivariable, linear regression, and repeated measures analyses to study the association between DM and baseline health status initially and over 3 to 12 months. Models were adjusted for demographics, socioeconomic factors, PAD severity, comorbidities, and psychosocial characteristics. The interaction of DM with PAD revascularization on 3‐ to 12‐month health status was also tested. Of 1204 patients, 398 (33%) had DM (94% type 2). Patients with versus those without DM had lower unadjusted PAQ summary scores at baseline and 3, 6, and 12 months (46.1 versus 50.8, 63.6 versus 68.2, 65.7 versus 71.7, and 65.4 versus 72.6; P≤0.01). In fully adjusted models, the effect of DM on baseline (mean difference, −0.65; 95% CI, −2.86 to 1.56 [P=0.56]) and over 3‐ to 12‐month PAQ summary scores (mean difference, −1.59; 95% CI, −4.06 to 0.88 [P=0.21]) was no longer significant. Twelve‐month health status gains following revascularization were similar in both groups (P=0.69).

Conclusions

Patients with PAD with coexisting DM have poorer health status, mostly explained by the differences in their psychosocial and other comorbidity burden. Patients with PAD and DM versus those without DM experience similar health status benefits following PAD revascularization.

Incentivizing physical activity through activity monitoring interventions in PAD - a pilot study

Background: There is ample evidence to show that supervised exercise is efficacious and cost effective for improving claudication symptoms in patients with peripheral artery disease (PAD). Home based exercise therapy can be an effective alternative to supervised exercise however, the results of this is variable depending on the level of motivation and engagement of the patient. Patients and methods: We performed a pilot study in 41 patients to determine whether a home based exercise program with the use of an activity tracking device with personalized feedback and financial incentives can increase daily activity, improve walking and sustain engagement in the exercise regimen in patients with PAD. In this randomized pilot study, the patients in the study group were fitted with an activity monitoring device and given behavioral monitoring, motivational updates and feedback regarding their exercise program. This study group was further divided in to two groups. One half of these patients in the study group were also given financial incentives if they reached their set targets. The control group wore the device with no feedback or ability to see their number of steps walked. Results: Results showed that at the end of the 12 week period, patients in the study groups walked more compared to the controls and the financial incentive structure resulted in an additional 38-63% increase in average daily steps. Conclusions: This pilot study revealed that a home-based exercise program with activity monitoring, feedback and financial incentives resulted increased daily steps, 6-minute walking distance and overall compliance with the program in PAD patients with claudication.

A randomized controlled trial of treatment with intermittent negative pressure for intermittent claudication

OBJECTIVE

We investigated the effects of lower extremity intermittent negative pressure (INP) treatment for 1 hour two times daily for 12 weeks on the walking distance of patients with intermittent claudication (IC).

METHODS

Patients with IC were randomized to treatment with -40 mm Hg INP (treatment group) or -10 mm Hg INP (sham control group). Pain-free walking distance (PWD) and maximal walking distance (MWD) on a treadmill, resting and postexercise ankle-brachial index, resting and postischemic blood flow (plethysmography), and quality of life (EQ-5D-5L and Vascuqol-6) were measured at baseline and after 12 weeks of treatment.

RESULTS

A total of 72 patients were randomized, and 63 had data available for the intention-to-treat analyses. The between-group comparisons showed a significant change in the PWD, favoring the treatment group over the sham control group (estimated treatment effect, 50 m; 95% confidence interval [CI], 11-89; P = .014). The PWD had increased by 68 m (P < .001) in the treatment group and 18 m (P = .064) in the sham control group. No significant difference was found in the change in the MWD between the two groups (estimated treatment effect, 42 m; 95% CI, -14 to 97; P = .139). The MWD had increased by 62 m (P = .006) in the treatment group and 20 m (P = .265) in the sham control group. For patients with a baseline PWD of <200 m (n = 56), significant changes had occurred in both PWD and MWD between the two groups, favoring the treatment group (estimated treatment effect, 42 m; 95% CI, 2-83; P = .042; and estimated treatment effect, 62 m; 95% CI, 5-118; P = .032; respectively). Both overall and for the group of patients with a PWD <200 m, no significant differences were found in the changes in the resting and postexercise ankle-brachial index, resting and postischemic blood flow, or quality of life parameters between the two groups.

CONCLUSIONS

Treatment with -40 mm Hg INP increased the PWD compared with sham treatment in patients with IC. For the patients with a baseline PWD of <200 m, an increase was found in both PWD and MWD compared with sham treatment.

Association of Health Status Scores With Cardiovascular and Limb Outcomes in Patients With Symptomatic Peripheral Artery Disease: Insights From the EUCLID (Examining Use of Ticagrelor in Symptomatic Peripheral Artery Disease) Trial

Background There are limited data on health status instruments in patients with peripheral artery disease and cardiovascular and limb events. We evaluated the relationship between health status changes and cardiovascular and limb events. Methods and Results In an analysis of the EUCLID (Examining Use of Ticagrelor in Symptomatic Peripheral Artery Disease) trial, we examined the characteristics of 13 801 patients by tertile of health status instrument scores collected in the trial (EuroQol 5-Dimensions [EQ-5D], EQ visual analog scale [VAS], and peripheral artery questionnaire). We assessed the association between the baseline health status measurements and major adverse cardiovascular events, major adverse limb events, and lower-extremity revascularization procedures during trial follow-up and the association between 12-month health status change scores and subsequent end points during follow-up. There were 13 217 (95%) patients with EQ-5D scores, 13 533 (98%) with VAS scores, and 4431 (32%) with peripheral artery questionnaire scores. Patients in the lowest baseline EQ-5D tertile (0 to <0.69) were more likely to be female with severe claudication compared with the highest tertile (0.79-1.0; P<0.01). Patients in the lowest VAS (0-60) and peripheral artery questionnaire (0-49) tertiles had lower ankle-brachial indices compared with the highest tertiles (80-100 and 76-108, respectively; P<0.01). There was a significant association between baseline EQ-5D, VAS, and peripheral artery questionnaire scores and adjusted major adverse cardiovascular events, major adverse limb events, and lower-extremity revascularization (P<0.05). Improved EQ-5D and VAS scores over 12 months were associated with reduced risk of subsequent major adverse cardiovascular events or lower-extremity revascularization (all P<0.01). Conclusions Although health status instruments are rarely used in clinical practice, these measures are associated with outcomes, including major adverse cardiovascular events, major adverse limb events, and lower-extremity revascularization. Further research is needed to determine the relationship between changes in these instruments, revascularization, and outcomes.

Lower extremity artery disease in patients with type 2 diabetes

Among all peripheral arterial diseases, lower extremity arterial disease is a serious condition in subjects with type 2 diabetes mellitus, associated with important disability, cardiovascular risk, and socio-economic burden. Patients with both conditions generally display poorer prognosis of affected limbs compared with non-diabetic subjects, leading to increased rates of adverse limb events including amputations. Nonetheless, awareness on lower extremity arterial disease remains somehow suboptimal in the diabetic population, partly related to an atypical clinical presentation in several cases. A regular and appropriate screening for lower extremity arterial disease in patients suffering from type 2 diabetes mellitus is therefore recommended. Affected subjects should receive optimal medical treatment including careful management of the different cardiovascular risk factors through a healthy lifestyle, a regular and structured physical activity, the administration of lipid-lowering, antidiabetic drugs, and (when indicated) antihypertensive and antithrombotic drugs. This review aims to outline current evidence about lower extremity arterial disease in patients with type 2 diabetes mellitus, in order to elucidate its epidemiology, pathophysiology, screening and diagnosis, and management options.

Exercise enhances mitochondrial fission and mitophagy to improve myopathy following critical limb ischemia in elderly mice via the PGC1a/FNDC5/irisin pathway

Background

Elderly populations are susceptible to critical limb ischemia (CLI), but conventional treatments cannot significantly decrease amputation and mortality. Although exercise is an effective “non-pharmacological medicine” targeting mitochondria to improve skeletal muscle function, few studies have focused on the application of exercise in CLI.

Methods

Elderly male C57BL/6 mice (14 months old) were used to establish a CLI model to assess the effect of exercise on perfusion, performance recovery, apoptosis, mitochondrial function, and mitochondrial turnover in gastrocnemius muscle. The potential underlying mechanism mediated by PGC1a/FNDC5/irisin was confirmed in hypoxic and nutrient-deprived myotubes undergoing electrical pulse stimuli (EPS).

Results

Exercise significantly accelerated the perfusion recovery and exercise performance in ischemic limbs following CLI. Exercise improved the mitochondrial membrane potential and total ATP production and decreased apoptosis in the ischemic limbs. Exercise increased the formation of mitochondrial derived vesicle-like structures and decreased the mitochondrial length in the ischemic limbs, accompanied by upregulated PGC1a/FNDC5/irisin expression. In vitro, PGC1a/FNDC5/irisin downregulation decreased EPS-elevated PINK1, Parkin, DRP1, and LC3B mRNA levels. The irisin levels in the culture medium were correlated with the expression of mitochondrial fission and mitophagy markers in myotubes.

Conclusion

Exercise enhanced mitochondrial fission and selective autophagy to promote the recovery of myopathy after CLI in elderly mice through the PGC1a/FNDC5/irisin pathway, supporting the efficacy of exercise therapy in elderly individuals with CLI and demonstrating the potential of targeting PGC1a/FNDC5/irisin as a new strategy for the treatment of CLI.

Successful Implementation of the Exercise First Approach for Intermittent Claudication in the Netherlands is Associated with Few Lower Limb Revascularisations

OBJECTIVE

A stepped care model, in which patients are primarily treated with supervised exercise therapy (SET), is recommended as the optimal strategy for intermittent claudication (IC). The aim of this study was to determine the primary treatment (SET, endovascular revascularisation [ER], or open surgery) in relation to secondary lower limb revascularisation and survival in patients with IC.

METHODS

This study was a nationwide retrospective data analysis of health insurance claims of patients newly diagnosed with IC between January 2013 and December 2017. Exclusion criteria were the presence of diagnostic codes for critical limb ischaemia or for a diabetic foot. Study outcomes were distribution of primary treatment modalities, freedom from secondary lower limb revascularisation, and overall five year survival. Analysis included Kaplan-Meier method and Cox proportional hazards regression models with adjustment for multiple confounders (age, gender, socioeconomic status, use of diabetes medication, statins, platelet aggregation inhibitors or anticoagulants, presence of cardiac disease, chronic obstructive pulmonary disease, and pre-dialysis).

RESULTS

The five year cohort included 54 504 patients with IC (primary SET n = 39 476, primary ER n = 11 769, and primary open surgery n = 3 259). SET as primary treatment increased from 63% in 2013 to 87% in 2017. Patients who underwent ER or open surgery as a primary treatment had a higher risk of secondary revascularisations (hazard ratio [HR] 1.44; 95% confidence interval [CI] 1.37-1.51; p < .001 and HR 1.45; 95% CI 1.34-1.57; p < .001, respectively) and a higher mortality risk compared with SET as a primary treatment (HR 1.38; 95% CI 1.29-1.48; p < .001 and HR 1.49; 95% CI 1.34-1.65; p < .001, respectively).

CONCLUSION

Guideline adherence improved to 87% in Dutch patients with IC. Patients receiving primary SET had fewer lower limb revascularisations and demonstrated better survival than patients undergoing primary ER or open surgery.

Skeletal muscle capillary density is related to anaerobic threshold and claudication in peripheral artery disease

Peripheral artery disease (PAD) is characterized by impaired blood flow to the lower extremities, causing claudication and exercise intolerance. Exercise intolerance may result from reduced skeletal muscle capillary density and impaired muscle oxygen delivery. This cross-sectional study tested the hypothesis that capillary density is related to claudication times and anaerobic threshold (AT) in patients with PAD. A total of 37 patients with PAD and 29 control subjects performed cardiopulmonary exercise testing on a treadmill for AT and gastrocnemius muscle biopsies. Skeletal muscle capillary density was measured using immunofluorescence staining. PAD had decreased capillary density (278 ± 87 vs 331 ± 86 endothelial cells/mm², p = 0.05), peak VO₂ (15.7 ± 3.9 vs 24.3 ± 5.2 mL/kg/min, p ⩽ 0.001), and VO₂ at AT (11.5 ± 2.6 vs 16.1 ± 2.8 mL/kg/min, p ⩽ 0.001) compared to control subjects. In patients with PAD, but not control subjects, capillary density was related to VO₂ at AT (r = 0.343; p = 0.038), time to AT (r = 0.381; p = 0.020), and time after AT to test termination (r = 0.610; p ⩽ 0.001). Capillary density was also related to time to claudication (r = 0.332; p = 0.038) and time after claudication to test termination (r = 0.584; p ⩽ 0.001). In conclusion, relationships between capillary density, AT, and claudication symptoms indicate that, in PAD, exercise limitations are likely partially dependent on limited skeletal muscle capillary density and oxidative metabolism.

Effect of conservative treatment in aortoiliac occlusive disease

Objective: To determine the effect of primary conservative treatment without revascularization in patients with proven aortoiliac occlusive disease (AIOD) presenting with intermittent claudication (IC).Background: The initial treatment of IC should focus on supervised exercise therapy (SET) and pharmacotherapy. Nowadays, primary endovascular revascularization (EVR) has become increasingly popular in patients with all types of AIOD. But in daily practice, EVR is often performed without initially extensive exercise.Method: This is a single centre retrospective study from December 2012 to September 2017. Primary outcomes were maximum walking distance (MWD) and patient satisfaction. Secondary outcomes were revascularization rate and mortality.Results: Twenty-four patients were included. Mean age was 64 years (SD: 9). Mean follow-up was 28 months (SD: 17). Nineteen patients (80%) had SET. In 18 (75%) patients, the MWD was improved compared to the initial situation. In five (21%) patients, the MWD stayed the same. The MWD of one (4%) patient decreased. Overall satisfaction rate was 87%. Three patients (13%) were not satisfied with the conservative treatment and eventually got an EVR. There was no disease related death.Conclusions: Conservative treatment, especially with SET, has acceptable subjective symptom outcomes in selected patients with AIOD. It could be a good alternative treatment for certain patients with AIOD and IC.

High INtensity Interval Training In pATiEnts with intermittent claudication (INITIATE): protocol for a multicentre, proof-of-concept, prospective interventional study

INTRODUCTION

The first-line recommended treatment for patients with intermittent claudication (IC) is a supervised exercise programme (SEP), which includes a minimum of 2-hours of exercise per week over a 12-week period. However, provision, uptake and adherence rates for these SEP programmes are poor, with time constraints cited as a common participant barrier. High-intensity interval training (HIIT) is more time-efficient and therefore has the potential to overcome this barrier. However, evidence is lacking for the role of HIIT in those with IC. This proof-of-concept study aims to consider the safety, feasibility, tolerability and acceptability of a HIIT programme for patients with IC.

METHODS AND ANALYSIS

This multicentre, single-group, prospective, interventional feasibility study will recruit 40 patients with IC, who will complete 6 weeks of HIIT, 3 times a week. HIIT will involve a supervised programme of 10×1 min high-intensity cycling intervals at 85%-90% peak power output (PPO), interspaced with 10×1 min low intensity intervals at 20%-25% PPO. PPO will be determined from a baseline cardiopulmonary exercise test (CPET) and it is intended that patients will achieve ≥85% of maximum heart rate from CPET, by the end of the second HIIT interval. Primary outcome measures are safety (occurrence of adverse events directly related to the study), programme feasibility (including participant eligibility, recruitment and completion rates) and HIIT tolerability (ability to achieve and maintain the required intensity). Secondary outcomes include patient acceptability, walking distance, CPET cardiorespiratory fitness measures and quality of life outcomes.

ETHICS AND DISSEMINATION

Ethical approval was obtained via a local National Health Service research ethics committee (Bradford Leeds - 18/YH/0112) and recruitment began in August 2019 and will be completed in October 2020. Results will be published in peer-reviewed journals and presented at international conferences and are expected to inform a future pilot randomised controlled trial of HIIT versus usual-care SEPs.

TRIAL REGISTRATION NUMBER

NCT04042311; Pre-results.

Impact of Kidney Disease on Peripheral Arterial Interventions: A Systematic Review and Meta-Analysis

BACKGROUND

There are limited data on outcomes of patients undergoing peripheral arterial disease (PAD) interventions who have comorbid CKD/ESRD versus those who do not have such comorbid condition. We performed a systematic review and meta-analysis to analyze outcomes in this patient population.

METHODS

Five databases were searched for studies comparing outcomes of lower extremity PAD interventions for claudication and critical limb ischemia (CLI) in patients with CKD/ESRD versus non-CKD/non-ESRD from January 2000 to June 2019.

RESULTS

Our study included 16 observational studies with 44,138 patients. Mean follow-up was 48.9 ± 27.4 months. Major amputation was higher with CKD/ESRD compared with non-CKD/non-ESRD (odds ratio [OR 1.97] [95% confidence interval [CI] 1.39-2.80], p = 0.001). Higher major amputations with CKD/ESRD versus non-CKD/non-ESRD were only observed when indication for procedure was CLI (OR 2.27 [95% CI 1.53-3.36], p < 0.0001) but were similar for claudication (OR 1.15 [95% CI 0.53-2.49], p = 0.72). The risk of early mortality was high with CKD/ESRD patients undergoing PAD interventions compared with non-CKD/non-ESRD (OR 2.55 [95% CI 1.65-3.96], p < 0.0001), which when stratified based on indication, remained higher with CLI (OR 3.14 [95% CI 1.80-5.48], p < 0.0001) but was similar with claudication (OR 1.83 [95% CI 0.90-3.72], p = 0.1). Funnel plot of included studies showed moderate bias.

CONCLUSIONS

Patients undergoing lower extremity PAD interventions for CLI who also have comorbid CKD/ESRD have an increased risk of experiencing major amputations and early mortality. Randomized trials to understand outcomes of PAD interventions in this at-risk population are essential.

Why to evaluate the functional capacity in PAD patients?

Summary: In patients with peripheral arterial disease (PAD), the ability to perform physical exercise is an essential and most important indicator of a patient’s health and quality of life. In many cases, there exists a discrepancy between lower extremity blood flow, the extent of arterial occlusion shown by morphological investigation and functional impairment. Reversal of lower extremity arterial obstruction with revascularization does not always reverse functional impairment of diseased leg. Further, training exercise and drug treatment can improve functional performance although they are not associated with an improvement in arterial obstruction. Therefore, the determination of functional impairment and its recovery after different therapeutic procedures should be determined using objective tests. The most frequently used functional tests are treadmill exercise testing and a 6-minute walk test. The constant load test, in which results are expressed as a walked distance, does not always permit an accurate assessment of the full range of functional impairment of PAD patients. Recently, as a substitute for a constant-load test, the graded treadmill test is used. With this test, it is possible to identify those individuals with exercise limitations who are not caused only by deterioration of the blood flow of lower limbs. The 6-minute walk test is simple to perform and requires minimal equipment. However, the correlation between the 6-minute walk test and the graded treadmill test is relatively weak, indicating that peak performance on a graded treadmill may reflect different pathophysiological mechanisms of limitations. In conclusion: for the determination of limitations of mobility and quality of life in patients with PAD, objective measures of functional impairment are needed. The determination of functional capacity is related to the quality of life and is a useful tool for investigation of the success of revascularization of peripheral arteries and conservative treatment.

Polonsky T, Leeuwenburgh C, Ferrucci L, Peterson CA. Correlations of Calf Muscle Macrophage Content With Muscle Properties and Walking Performance in Peripheral Artery Disease

Background Peripheral artery disease (PAD) is a manifestation of atherosclerosis characterized by reduced blood flow to the lower extremities and mobility loss. Preliminary evidence suggests PAD damages skeletal muscle, resulting in muscle impairments that contribute to functional decline. We sought to determine whether PAD is associated with an altered macrophage profile in gastrocnemius muscles and whether muscle macrophage populations are associated with impaired muscle phenotype and walking performance in patients with PAD. Methods and Results Macrophages, satellite cells, and extracellular matrix in gastrocnemius muscles from 25 patients with PAD and 7 patients without PAD were quantified using immunohistochemistry. Among patients with PAD, both the absolute number and percentage of cluster of differentiation (CD) 11b+CD206+ M2-like macrophages positively correlated to satellite cell number (r=0.461 [P=0.023] and r=0.416 [P=0.042], respectively) but not capillary density or extracellular matrix. The number of CD11b+CD206- macrophages negatively correlated to 4-meter walk tests at normal (r=-0.447, P=0.036) and fast pace (r=-0.510, P=0.014). Extracellular matrix occupied more muscle area in PAD compared with non-PAD (8.72±2.19% versus 5.30±1.03%, P<0.001) and positively correlated with capillary density (r=0.656, P<0.001). Conclusions Among people with PAD, higher CD206+ M2-like macrophage abundance was associated with greater satellite cell numbers and muscle fiber size. Lower CD206- macrophage abundance was associated with better walking performance. Further study is needed to determine whether CD206+ macrophages are associated with ongoing reparative processes enabling skeletal muscle adaptation to damage with PAD. Registration URL: https://www.clini​caltr​ials.gov; Unique identifiers: NCT00693940, NCT01408901, NCT0224660.

A systematic review of lower extremity electrical stimulation for treatment of walking impairment in peripheral artery disease

Lower extremity peripheral artery disease (PAD) induces an ischemic pain in the lower limbs and leads to walking impairment. Electrical stimulation has been used in patients with PAD, but no systematic review has been proposed to address the efficacy of the technique as a treatment for walking impairment in PAD. A systematic search was performed to identify trials focused on electrical stimulation for the treatment of walking impairment in patients with PAD in the Cochrane Central Register, PubMed, Embase, and the Web of Science. Studies were included where the primary outcomes were pain-free walking distance and/or maximal walking distance. When appropriate, eligible studies were independently assessed for quality using the Cochrane Collaboration's tool for assessing risk of bias. Five studies eligible for inclusion were identified, of which only two were randomized controlled studies. Trial heterogeneity prevented the use of the GRADE system and the implementation of a meta-analysis. Three types of electrical stimulation have been used: neuromuscular electrical stimulation (NMES, n = 3), transcutaneous electrical stimulation (n = 1), and functional electrical stimulation (n = 1). The two available randomized controlled studies reported a significant improvement in maximal walking distance (+40 m/+34% and +39 m/+35%, respectively) following a program of NMES. Owing to the low number of eligible studies, small sample size, and the risk of bias, no clear clinical indication can be drawn regarding the efficacy of electrical stimulation for the management of impaired walking function in patients with PAD. Future high-quality studies are required to define objectively the effect of electrical stimulation on walking capacity.

Device Selection in Femoral-Popliteal Arterial Interventions

Endovascular intervention devices for femoral-popliteal arterial disease have evolved in the last decade to more effectively treat patients with symptoms of claudication, improve tissue healing, and prevent amputation in patients with critical limb ischemia. Drug-eluting stents and drug-coated balloon therapies have demonstrated significant improvements in short- and mid-term patency and decreases in future target vessel interventions over uncoated balloon angioplasty. Adjunctive lesion preparation options including atherectomy devices are available to treat more complex and calcified lesions, but comparative data are still required.

Iliac Artery Intervention

Endovascular revascularization for aortoiliac occlusive disease (AIOD) is now considered first-line therapy for patients with claudication and critical limb ischemia and in asymptomatic patients in whom large-bore access is required (eg, mechanical circulatory support or transcatheter aortic valve replacement). The authors review the data supporting endovascular therapy for AIOD, indications and contraindications for AIOD revascularization, as well as the procedural techniques required to safely perform endovascular therapy in this vascular bed. They review prevention and management of the major complications that can occur during these procedures. Finally, they discuss postprocedural management to maintain patency and optimize patient outcomes.

Assessment of behavioral determinants influencing success of supervised exercise therapy in patients with intermittent claudication: A cross sectional survey

BACKGROUND

Supervised exercise therapy is the first step in treatment of intermittent claudication. However, adherence to supervised exercise therapy is low. Limited access and reimbursement issues are known reasons, though lack of motivation is often leading. Behavioral determinants influencing motivation and thus adherence to supervised exercise therapy remain to be investigated. In this study we sought to determine which behavioral determinants would be of influence on the long-term adherence of supervised exercise therapy.

METHODS

200 patients, newly diagnosed with peripheral arterial disease Rutherford classification II-III, were sent a questionnaire to assess motivation and behavior with regard to supervised exercise therapy. The questionnaire was constructed using the I-CHANGE model for explaining motivational and behavioral change. Baseline characteristics were acquired from medical records. Alpha Cronbach's was calculated to test reliability of the questionnaire.

RESULTS

108 (54%) patients returned their questionnaire. A total of 79% patients followed supervised exercise therapy. Patients who increased their walking distance after supervised exercise therapy have significantly greater knowledge (p = 0.05), positive attitude (p = 0.03) and lower negative attitude (p = 0.01). Patients with a higher self-efficacy remained significantly more active after participating in supervised exercise therapy (p = 0.05).

CONCLUSION

Increasing the determinants knowledge, attitude and self-efficacy will improve adherence to supervised exercise therapy and result in delayed claudication onset time.

Quantitative and Dynamic MRI Measures of Peripheral Vascular Function

The endothelium regulates and mediates vascular homeostasis, allowing for dynamic changes of blood flow in response to mechanical and chemical stimuli. Endothelial dysfunction underlies many diseases and is purported to be the earliest pathologic change in the progression of atherosclerotic disease. Peripheral vascular function can be interrogated by measuring the response kinetics following induced ischemia or exercise. In the presence of endothelial dysfunction, there is a blunting and delay of the hyperemic response, which can be measured non-invasively using a variety of quantitative magnetic resonance imaging (MRI) methods. In this review, we summarize recent developments in non-contrast, proton MRI for dynamic quantification of blood flow and oxygenation. Methodologic description is provided for: blood oxygenation-level dependent (BOLD) signal that reflect combined effect of blood flow and capillary bed oxygen content; arterial spin labeling (ASL) for quantification of regional perfusion; phase contrast (PC) to quantify arterial flow waveforms and macrovascular blood flow velocity and rate; high-resolution MRI for luminal flow-mediated dilation; and dynamic MR oximetry to quantify oxygen saturation. Overall, results suggest that these dynamic and quantitative MRI methods can detect endothelial dysfunction both in the presence of overt cardiovascular disease (such as in patients with peripheral artery disease), as well as in sub-clinical settings (i.e., in chronic smokers, non-smokers exposed to e-cigarette aerosol, and as a function of age). Thus far, these tools have been relegated to the realm of research, used as biomarkers of disease progression and therapeutic response. With proper validation, MRI-measures of vascular function may ultimately be used to complement the standard clinical workup, providing additional insight into the optimal treatment strategy and evaluation of treatment efficacy.

Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals.

RESULTS

Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Absence of Long-Term Benefit of Revascularization in Patients With Intermittent Claudication: Five-Year Results From the IRONIC Randomized Controlled Trial

BACKGROUND

The long-term benefit of revascularization for intermittent claudication is poorly understood. The aim of this study was to investigate the long-term effectiveness and cost-effectiveness compared with a noninvasive approach.

METHODS

The IRONIC trial (Invasive Revascularization or Not in Intermittent Claudication) randomized patients with mild-to-severe intermittent claudication to either revascularization + best medical therapy + structured exercise therapy (the revascularization group) or best medical therapy + structured exercise therapy (the nonrevascularization group). The health-related quality of life short form 36 questionnaire was primary outcome and disease-specific health-related quality of life (vascular quality of life questionnaire) and treadmill walking distances were secondary end points. Health-related quality of life has previously been reported superior in the revascularization group at 1- and 2-year follow-up. In this study, the 5-year results were determined. The cost-effectiveness of the treatment options was analyzed from a payer/healthcare standpoint.

RESULTS

Altogether, 158 patients were randomized in a 1:1 ratio. Regarding the primary end point, no intergroup differences were observed for the short form 36 sum or domain scores from baseline to 5 years, except for the short form 36 role emotional domain score, with greater improvement in the nonrevascularization group (n=116, P=0.007). No intergroup differences were observed in the vascular quality of life questionnaire total and domain scores (n=116, NS) or in treadmill walking distances (n=91, NS). A revascularization strategy resulted in almost twice the cost per patient compared with a noninvasive treatment approach ($13 098 versus $6965, P=0.02).

CONCLUSIONS

After 5 years of follow-up, a revascularization strategy had lost its early benefit and did not result in any long-term improvement in health-related quality of life or walking capacity compared to a noninvasive treatment strategy. Revascularization was not a cost-effective treatment option from a payer/healthcare point of view.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01219842.

Durability of Benefits From Supervised Treadmill Exercise in People With Peripheral Artery Disease

Background It is currently unknown whether 6 months of supervised treadmill exercise has a durable benefit on 6-minute walk performance, even after exercise is completed, in people with peripheral artery disease. Methods and Results A total of 156 participants with peripheral artery disease were randomized to 1 of 3 groups: supervised treadmill exercise, supervised resistance training, or attention control. Participants received supervised sessions during months 1 to 6 and telephone contact during months 6 to 12. Primary outcomes were change in 6-minute walk distance and short physical performance battery at 6-month follow-up and have been reported previously. Secondary outcomes were change in 6-minute walk and short physical performance battery at 12-month follow-up and are reported here. A group of 134 participants (86%) completed the 12-month follow-up. At 6-month follow-up, compared with control, 6-minute walk distance improved in the treadmill exercise group (+36.1 m, 95% CI =13.9-58.3, P=0.001). Between 6- and 12-month follow-up, 6-minute walk distance significantly declined (-28.6 m, 95% CI=-52.6 to -4.5, P=0.020) and physical activity declined -272 activity units (95% CI =-546 to +2, P=0.052) in the treadmill exercise group compared with controls. At 12-month follow-up, 6 months after completing supervised treadmill exercise, change in 6-minute walk distance was not different between the treadmill exercise and control groups (+7.5, 95% CI =-17.5 to +32.6, P=0.56). There were no differences in short physical performance battery change between either exercise group and control at 6-month or 12-month follow-up. Conclusions A 6-month supervised treadmill exercise intervention that improved 6-minute walk distance at 6-month follow-up did not have persistent benefit at 12-month follow-up. These results do not support a durable benefit of supervised treadmill exercise in peripheral artery disease. Clinical Trial Registration URL : https://www.clinicaltrials.gov . Identifier: NCT 00106327.

Exercise and Peripheral Arteriosclerosis

Adaptation of a healthy lifestyle including adequate daily physical activity is shown to reduce 80% of cardiovascular mortality and 40% of cancer-related deaths. A large body of evidence exists proving that this relationship is dose dependent, and even half of the recommended normal physical activity yields significant risk reduction. There has been no medical therapy that would provide such high percentages of reduction in mortality to date. The World Health Organization, therefore, has started an initiative to implement exercise into daily life as a primary prevention measure. Herein, we will focus on the effects of exercise on the vasculature, mainly the peripheral vasculature, in the context of atherosclerotic disease. Exercise has a fundamental role in the pathogenesis, diagnosis, and treatment of atherosclerotic vascular disease. It exerts a protective effect against the development of atherosclerosis irrespective of other cardiovascular risk factors. Additionally, exercise induces changes in vascular hemodynamics helping us to elucidate the presence of obscure vascular involvement. Once again, exercise is the main treatment modality in peripheral arterial disease with accumulating evidence to reduce symptoms and improve both exercise capacity and cardiovascular symptoms.