Society for Vascular Surgery Practice guidelines for atherosclerotic occlusive disease of the lower extremities management of asymptomatic disease and claudication. Introduction

Clinical Implications of Low Body Mass Index on Endovascular Lower Extremity Revascularization

BACKGROUND

The epidemic of obesity and associated cardiovascular morbidity continues to grow, attracting public attention and healthcare resources. However, the impact of malnutrition and being underweight continues to be overshadowed by obesity, especially in patients with peripheral arterial disease (PAD). This study assesses the characteristics and outcomes of patients with low body mass index (BMI ≤ 18.5) compared to patients with nonobese BMI undergoing peripheral vascular interventions (PVI).

METHODS

A retrospective analysis of patients undergoing PVI due to PAD registered in the Vascular Quality Initiative database. Patients were categorized into underweight (BMI ≤ 18.5) and nonobese BMI (BMI = 18.5-30). Patients in both groups were matched 3:1 for baseline demographic characteristics, comorbidities, medications, and indications. Kaplan-Meier analysis was done for long-term outcomes.

RESULTS

A total of 337,926 patients underwent PVI, of whom 12,935 (4%) were underweight, 215,728 (64%) were nonobese, and 109,263 (32%) were obese. Underweight patients were more likely to be older, female, smokers, with chronic obstructive pulmonary disorder, and more likely to present with chronic limb-threatening ischemia than nonobese patients. After propensity matching, there were 18,047 nonobese patients and 6,031 underweight patients. There were no significant differences in matched characteristics. Perioperatively, underweight patients were more likely to require a longer hospital length of stay. Underweight patients had statistically significantly higher 30-day mortality compared to patients with nonobese BMI (3% vs. 1.6%, P < 0.001) and a higher rate of thrombotic complications. As for long-term outcomes, underweight patients had a higher rate of reintervention (20% vs. 18%, P < 0.001) and major adverse limb events (27% vs. 22%, P < 0.001). The 4-year rate of amputation-free survival was significantly lower in underweight patients (70% vs. 82%, P < 0.001), and the 2-year freedom from major amputation (90% vs. 94%, P < 0.001) showed similar trends with worse outcomes in patients who were underweight.

CONCLUSIONS

Underweight patients with PAD are disproportionally more likely to be African American, females, and smokers and suffer worse outcomes after PVI than PAD patients with nonobese BMI. When possible, increased scrutiny and optimization of nutrition and other factors contributing to low BMI should be addressed prior to PVI.

Co-Morbidity Differences Associated With Long-Term Amputation and Repeat Revascularization Rates After Femoropopliteal Artery Intervention for Intermittent Claudication by Sex, Race, and Ethnicity

Use of peripheral vascular intervention (PVI) for intermittent claudication (IC) continues to expand, but there is uncertainty whether baseline demographics, procedural techniques and outcomes differ by sex, race, and ethnicity. This study aimed to examine amputation and revascularization rates up to 4 years after femoropopliteal (FP) PVI for IC by sex, race, and ethnicity. Patients who underwent FP PVI for IC between 2016 and 2020 from the PINC AI Healthcare Database were analyzed. The primary outcome was any index limb amputation, assessed by Kaplan-Meier estimate. Secondary outcomes included index limb major amputation, repeat revascularization, and index limb repeat revascularization. Unadjusted and adjusted hazard ratios (HRs) were estimated using Cox proportional hazard regression models. This study included 19,324 patients with IC who underwent FP PVI, with 41.2% women, 15.6% Black patients, and 4.7% Hispanic patients. Women were less likely than men to be treated with atherectomy (45.1% vs 47.8%, p = 0.0003); Black patients were more likely than White patients to receive atherectomy (50.7% vs 44.9%, p <0.001), and Hispanic patients were less likely than non-Hispanic patients to receive atherectomy (41% vs 47%, p = 0.0004). Unadjusted rates of any amputation were similar in men and women (6.4% for each group, log-rank p = 0.842), higher in Black patients than in White patients (7.8% vs 6.1%, log-rank p = 0.007), and higher in Hispanic patients than in non-Hispanic patients (8.8% vs 6.3%, log-rank p = 0.031). After adjustment for baseline characteristics, Black race was associated with higher rates of repeat revascularization (adjusted HR 1.13, 95% confidence interval 1.04 to 1.22) and any FP revascularization (adjusted HR 1.10, 95% confidence interval 1.01 to 1.20). No statistical difference in amputation rate was observed among comparison groups. Women and men with IC had similar crude and adjusted amputation and revascularization outcomes after FP PVI. Black patients had higher repeat revascularization and any FP revascularization rates than did White patients. Black and Hispanic patients had higher crude amputation rates, but these differences were attenuated by adjustment for baseline characteristics. Black patients were more likely to receive atherectomy and had higher rates of any repeat revascularization and specifically FP revascularization. Further study is necessary to determine whether these patterns are related to disease-specific issues or practice-pattern differences among different populations.

Innovative nomogram for predicting 1-year clinically driven revascularization outcomes in endovascular femoropopliteal disease

Purpose

Femoropopliteal artery disease (FPAD) is a common vascular disease that usually requires surgical treatment. The aim of this study was to apply predictive modeling to develop predictive models for predicting clinically driven target revascularization (CD-TLR) events 1 year after intervention in patients with FPAD.

Materials and methods

In this study, clinical data were collected from a total of 484 patients who underwent FPAD endovascular intervention from 2014 to 2019. According to the inclusion and exclusion criteria, 400 patients will be finally included and assigned to the training cohort and test cohort in the ratio of 7:3. By analyzing these data through statistical methods, we will explore the effects of different factors on target revascularization events 1 year after intervention in FPAD patients, and build the corresponding prediction model of the column line graph.

Results

The final nomogram model consisted of 5 independent predictors: history of cerebrovascular disease, lesion length >15 cm, no atherectomy device used, no medicated balloon used and procedure time. The C-index of the model was 0.766 and 0.726 for the training cohort and validation cohort, respectively. The calibration curves also showed that the model had satisfactory agreement in both cohorts.

Conclusions

The newly developed prediction model can accurately predict clinically driven target revascularization events at 1 year in patients with FPAD, providing valuable information for the development of individualized treatment plans.

DETOUR2 trial outcomes demonstrate clinical utility of percutaneous transmural bypass for the treatment of long segment, complex femoropopliteal disease

OBJECTIVE

Percutaneous transmural arterial bypass (PTAB) using the DETOUR system aims to create a percutaneous, endovascular femoropopliteal bypass for the treatment of long segment, complex superficial femoral and proximal popliteal artery disease. The goal of the DETOUR2 study is to investigate the safety and effectiveness of the therapy in comparison with pre-established performance goals.

METHODS

The DETOUR2 investigational device exemption study is a prospective, single-arm, multicenter, international trial of symptomatic peripheral arterial disease patients (Rutherford classes 3-5) undergoing the DETOUR procedure for long segment (>20 cm) superficial femoral artery disease. Prespecified end points included primary safety (composite of major adverse events) at 30 days, and effectiveness (primary patency defined as freedom from restenosis or clinically driven target lesion revascularization) at 1 year.

RESULTS

We enrolled 202 patients at 32 sites with 200 treated with the DETOUR system. The mean lesion length was 32.7 cm, of which 96% were chronic total occlusions (CTO) and 70% were severely calcified. Technical success was achieved in 100% of treated patients. The primary safety end point was met with a 30-day freedom from major adverse event rate of 93.0%. The 1-year primary effectiveness end point was met with 72.1% primary patency at 12 months. Primary-assisted and secondary patency were 77.7% and 89.0%, respectively, at 12 months. The 12 month deep venous thrombosis incidence was 4.1% with no pulmonary emboli reported. Venous quality-of-life scores showed no significant changes from baseline. There was a Rutherford improvement of at least one class through 12 months in 97.2% of patients. The mean ankle-brachial index also improved from 0.61 to 0.95 during this period. There were marked improvements in quality-of-life and functional status measures.

CONCLUSIONS

The DETOUR2 study met both the primary safety and effectiveness end points, demonstrating clinical usefulness of this novel therapeutic strategy in long femoropopliteal lesions.

The effects of CYP2C19 genotype polymorphism and clopidogrel resistance on ischemic event occurrence in patients with peripheral arterial disease undergoing revascularization: A prospective cohort study

INTRODUCTION

Peripheral arterial disease (PAD) affects approximately 236 million people worldwide. Therefore, this study aimed to investigate the relationship between CYP2C19 genotype polymorphisms and clopidogrel resistance (CR) following revascularization in patients with PAD.

MATERIALS AND METHODS

In total, 345 patients who underwent PAD revascularization were monitored for five years and risk factors for ischemic events were identified. Platelet reactivity and CYP2C19 genotypes were measured, and patients were classified as normal, intermediate, or poor metabolizers based on their genotypes. The study endpoint was defined as an ischemic event, that encompassed major adverse cardiovascular or limb events, or all-cause death.

RESULTS

In this study, ischemic events following PAD revascularization were associated with patient age, prior minor amputation, the Rutherford category before revascularization, indications for revascularization, index ankle-branchial index before revascularization, CYP2C19 phenotypes, and CR. Intermediate and poor metabolism, the Rutherford category before revascularization, and CR were independent risk factors for ischemic events in patients after PAD revascularization. Similarly, intermediate and poor metabolism, the Rutherford category before revascularization, and CR were independent risk factors for ischemic events in patients with PAD after revascularization within five years. Intermediate and poor metabolizers had a higher platelet reactivity and risk of CR than normal metabolizers. However, poor metabolizers had a higher platelet reactivity and risk of CR than intermediate metabolizers. Furthermore, the hazard ratio for ischemic events increased with platelet reactivity. This effect was more prevalent in intermediate and poor metabolizers than in normal metabolizers.

CONCLUSIONS

Ischemic events in patients after PAD revascularization were affected by independent risk factors. Decreased clopidogrel metabolism increased the platelet reactivity and CR in patients after PAD revascularization. Furthermore, high platelet reactivity was associated with an increased risk of ischemic events in patients with intermediate and poor metabolism.

A Cost-Consequence Analysis Comparing Balloon-Expandable Covered Stents for the Management of Aortoiliac Occlusive Disease

PURPOSE

To compare procedural and long-term costs associated with the use of Balloon-Expandable Covered Stents (BECS) in the management of Aortoiliac Occlusive Disease (AIOD).

MATERIALS AND METHODS

A cost-consequence model was developed to simulate the intra- and post-operative management of patients with AIOD from the perspective of private health-payers. The study assessed the costs of the LifeStream (BD, Franklin Lakes, New Jersey), iCAST/Advanta V12 (Getinge, Goteborg, Sweden), BeGraft Peripheral (Bentley, Hechingen, Germany), and Viabahn Balloon Expandable (VBX) (W.L. Gore, Flagstaff, Arizona) BECS devices. Device costs were identified from the Australian Prosthesis List, whereas clinical outcomes of BECS were estimated from a systematic review of the literature. Costs were calculated over 24 and 36 month time horizons and reported in US dollars.

RESULTS

Long-term, per-patient cost of each device at 24 and 36 months was $6253/$6634 for the LifeStream; $6359/$6869 for the iCAST/Advanta V12; $4806 (data available to 24 months) for the BeGraft Peripheral; and $4839/$5046 for the Viabahn VBX, respectively. Most of the cost difference was attributed to the number of stents required per treated limb and frequency of clinically-driven target lesion revascularization events.

CONCLUSIONS

Best-available clinical evidence and economic modeling demonstrates that the BeGraft Peripheral and Viabahn VBX were of similar cost and the least costly options at 24 months, whereas at 36 months, the lowest cost BECS option for the treatment of AIOD was the Viabahn VBX.

CLINICAL IMPACT

This analysis supports economically informed decision-making for health-payers managing systems that care for patients with AIOD. Stent length and avoiding reintervention were identified as key areas of cost-saving for future BECS development.

Mid-term Results of Endovascular Reconstruction of Aortic Bifurcation Using COVERA Stent Graft

INTRODUCTION

This article aims to evaluate the short-term and mid-term performance of a self-expanding covered stent (COVERA Plus, Bard Tempe, Arizona) during the treatment of Trans-Atlantic Inter-Society Consensus (TASC) C/D aortoiliac obstructive lesions involving the aortic bifurcation.

METHODS

A single-center retrospective review of all patients who underwent endovascular reconstruction of the aortoiliac bifurcation for obstructive disease, with the use of Covera, from January 2018 to March 2023. All patients received a postoperative CTA (computed tomography angiography) scan within 1 month from the intervention. Precision of deployment, stent conformation, and stent symmetry were evaluated at the arterial phase of the CTA. Early outcomes were technical success and freedom from open aortic reintervention and/or mortality. Late outcomes were primary and assisted primary patency rates and freedom from reintervention.

RESULTS

During the study period, 35 patients underwent primary endovascular treatment of obstructive lesions involving the aortic bifurcation with parallel COVERA stents. Aortoiliac lesions were classified as TASC-IIC in 23 (65.7%) patients and TASC D in 12 (34.2%). Median follow-up was 49 months (interquartile [IQR]: 18-60). Overall survival was 97.1% (95% confidence interval [CI]=91-100) at 60 months. During follow-up, there were one early stent stenosis, treated with an angioplasty and stent relining with an estimated primary patency at 60 months of 97.1% (95% CI=94-100) and a primary-assisted patency of 100%. Estimated freedom from all types of reinterventions at 60 months was 94.3% (95% CI=89-99.3).

CONCLUSIONS

The new self-expanding covered Bard COVERA Plus stent used for endovascular treatment of TASC C/D aorto iliac disease proved to be safe and feasible with high technical procedural success rates. Comparison with other types of stents is necessary to further assess the role of the COVERA Plus stent in aortic bifurcation repair.

CLINICAL IMPACT

This study investigates the safety and feasibility of the new self-expanding covered Bard Covera Plus stent used for endovascular treatment of TASC C/D aorto iliac disease. The retrospective analysis of 35 patients highlights high technical success and primary patency rate at 60 months. The geometric analysis also helped to underline how this stent can be used precisely in particular conditions. These findings suggest the need for further research to compare COVERA with other types of stents in aortic bifurcation repair.

Therapeutic anticoagulation after index peripheral endovascular intervention in patients with claudication

OBJECTIVE

Antiplatelet agents are commonly used after peripheral endovascular intervention (PVI). However, the effect of full-dose anticoagulation on outcomes after PVI is not well-established. We sought to investigate whether full-dose anticoagulation after PVI is associated with adverse events.

METHODS

We utilized the Vascular Quality Initiative to study patients undergoing index PVI for claudication (2010-2019), stratified by the presence or absence of an anticoagulant on discharge. The primary outcomes were 2-year patency, major adverse limb events (MALE), and mortality. We built a propensity score adjusting for comorbidities and employed inverse probability weighting to estimate the association of anticoagulation with outcomes.

RESULTS

We identified 26,240 patients; 9.1% were discharged on an anticoagulant. Patients receiving any anticoagulation had a significantly higher risk of mortality (adjusted hazard ratio [aHR], 1.61; 95% confidence interval [CI], 1.35-1.92), but not MALE, or patency loss. Patients receiving a vitamin K antagonist had a significantly higher risk of patency loss (aHR, 1.32; 95% CI, 1.09-1.60), MALE (aHR, 1.33; 95% CI, 1.13-1.57), and mortality (aHR, 1.46; 95% CI, 1.27-1.69). Patients on an oral Factor Xa inhibitors had a significantly lower risk of patency loss (aHR, 0.61; 95% CI, 0.41-0.93) but increased mortality (aHR, 1.51; 95% CI, 1.19-1.92).

CONCLUSIONS

Therapeutic anticoagulation after PVI is associated with higher risk of all-cause mortality. Although oral Factor Xa inhibitors are associated with decreased risk of patency loss, vitamin K antagonists are associated with higher risk of patency loss, MALE, and death. Further prospective studies are necessary to study the safety and efficacy of full-dose anticoagulation after PVI.

Long-Term Patient Outcomes After Femoropopliteal Peripheral Vascular Intervention in Patients With Intermittent Claudication

BACKGROUND

In patients with intermittent claudication (IC), short-term amputation rates from clinical trial data following lower extremity femoropopliteal (FP) peripheral vascular intervention (PVI) are <1% with unknown longer-term rates.

OBJECTIVES

The aim of this study was to identify revascularization and amputation rates following PVI in the FP segment and to assess 4-year amputation and revascularization rates after FP PVI for IC.

METHODS

From 2016 to 2020, 19,324 patients undergoing FP PVI for IC were included from the PINC AI Healthcare Database and evaluated by treatment level (superficial femoral artery [SFA], popliteal artery [POP], or both). The primary outcome was index limb amputation (ILA) assessed by Kaplan-Meier estimate. The secondary outcomes were index limb major amputation and repeat revascularization. HRs were estimated using Cox proportional hazard regression.

RESULTS

The 4-year index limb amputation rate following FP PVI was 4.3% (95% CI: 4.0-4.7), with a major amputation rate of 3.2% (95% CI: 2.9-3.5). After POP PVI, ILA was significantly higher than SFA alone (7.5% vs 3.4%) or both segment PVI (5.5%). In multivariate analysis, POP PVI was associated with higher ILA rates at 4 years compared with isolated SFA PVI (HR: 2.10; 95% CI: 1.52-2.91) and index limb major amputation (HR: 1.98; 95% CI: 1.32-2.95). Repeat FP revascularization rates were 15.2%; they were highest in patients undergoing both SFA and POP PVI (18.7%; P < 0.0001) compared with SFA (13.9%) and POP (17.1%) only.

CONCLUSIONS

IC patients undergoing FP PVI had 4-year rates of index limb repeat revascularization of 16.7% and ILA rates of 4.3%. Further risk factors for amputation requires further investigation.

A framework for perioperative care for lower extremity vascular bypasses: A Consensus Statement by the Enhanced Recovery after Surgery (ERAS®) Society and Society for Vascular Surgery

The Society for Vascular Surgery and the Enhanced Recovery After Surgery (ERAS) Society formally collaborated and elected an international, multi-disciplinary panel of experts to review the literature and provide evidence-based suggestions for coordinated perioperative care for patients undergoing infrainguinal bypass surgery for peripheral artery disease. Structured around the ERAS core elements, 26 suggestions were made and organized into preadmission, preoperative, intraoperative, and postoperative sections.

Patterns of Care and Outcomes of Ambulatory Endovascular Interventions in Lower Extremity Peripheral Arterial Disease

Lower extremity endovascular intervention (LE-EVI) is gaining popularity as the primary treatment modality for patients with symptomatic peripheral artery disease refractory to noninvasive management. We examined the contemporary patterns of care, regional variation, and outcomes of ambulatory LE-EVI in the United States. The National Ambulatory Surgery Sample was analyzed to identify 266,563 records with peripheral artery disease and LE-EVI between January 1, 2016 and December 31, 2017. The mean age of the study cohort was 68.9 years and 40.5% were women. The majority of the endovascular interventions were performed at large (58.1%), urban teaching (64.1%), private not-for-profit (76.8%) centers, and the southern region accounted for most cases (43%). Periprocedural major adverse renal and cardiovascular events and other complications were 0.5% and 3.3%, respectively. Most patients (97.6%) were discharged home after the procedure. Age, female gender, uncontrolled hypertension, ischemic heart disease, heart failure, arrhythmia, chronic kidney disease, malnutrition, non-Medicare insurance, private for-profit, urban teaching facilities, and southern and midwest regions were associated with higher odds of major adverse renal and cardiovascular events. The mean charges per patient encounter were $56,500, with significant differences across various patient and facility characteristics. In conclusion, our study demonstrates the use, patterns of care, financial aspect, and overall safety of ambulatory LE-EVIs in a real-world setting.

Identifying potentially avoidable femoral to popliteal expanded polytetrafluoroethylene bypass for claudication using cross-site blinded peer review

OBJECTIVE

The surgical treatment of claudication can be associated with significant morbidity and costs. There are growing concerns that some patients proceed to interventions without first attempting evidence-based nonoperative management. We used a direct, cross-site, blinded expert review to evaluate the appropriateness of the surgical treatment of claudication.

METHODS

We enlisted practicing vascular surgeons to perform retrospective clinical assessments of lower extremity bypass procedures in a statewide clinical registry. Cases were limited to elective, open, infrainguinal bypasses performed for claudication using prosthetic grafts. Reviewing surgeons were randomly assigned 10 cases from a sample of 139 anonymized bypass operations and instructed to evaluate procedural appropriateness based on their expert opinion and evidence-based guidelines for preoperative treatment, namely, antiplatelet, statin, cilostazol, exercise, and smoking cessation therapy as documented in the medical record. Ninety-day episode payments were estimated from a distinct but similar cohort of patients undergoing lower extremity bypass for claudication.

RESULTS

Of 325 total reviews, surgeons stated they would not have recommended bypass in 134 reviews (41%) and deemed bypass inappropriate in 122 reviews (38%). The most common reason for inappropriateness was lack of preoperative medical and lifestyle therapy, which was present in 63% of reviews where bypass was deemed appropriate and 39% of reviews where bypass was deemed inappropriate (P < .001). Surgeons stated they would have recommended additional preoperative therapy in 65% of reviews where bypass was deemed inappropriate and 35% of reviews where bypass was deemed appropriate (P < .001). The mean total episode payments in a similar cohort of 1458 patients undergoing elective open lower extremity bypass for claudication were $31,301 ± $21,219. Extrapolating to the 325 reviews, the 134 reviews in which surgeons would not have recommended bypass were associated with potentially avoidable estimated total payments of $4,194,334, and the 122 reviews in which bypass was deemed inappropriate were associated with potentially avoidable estimated total payments of $3,818,722.

CONCLUSIONS

In this cross-site expert peer review study, 40% of lower extremity bypasses were deemed premature and, therefore, potentially avoidable, primarily owing to a lack of medical and lifestyle management before surgery. Reviews deemed inappropriate were associated with approximately $4 million in potentially avoidable costs. This approach could inform performance feedback among surgeons to help align clinical practice with evidence-based recommendations for the treatment of claudication.

A Pilot Study Examining the Effects of Ischemic Conditioning on Walking Capacity and Lower Extremity Muscle Performance in Patients with Claudication

INTRODUCTION

This study investigated whether a novel therapy called ischemic conditioning (IC) improves walking capacity and lower extremity muscle performance in patients with peripheral vascular disease who experience intermittent claudication.

METHODS

Forty-three patients with claudication were enrolled and received either IC or IC Sham for 2 weeks in this randomized, controlled, double-blinded, prospective study. IC sessions involved five cycles of alternating 5-min inflations of a blood pressure cuff to 225 mm Hg (25 mm Hg for IC Sham) and 5-min deflations, around the thigh of the affected lower extremity.

RESULTS

There was no difference in the change in claudication onset time (Δ = 114 ± 212 s IC vs. 104 ± 173 s IC Sham; p = 0.67) or peak walking time (Δ = 42 ± 139 s IC vs. 12 ± 148 s IC Sham; p = 0.35) between the IC and IC Sham groups. At the level of the knee, participants in the IC group performed more work (Δ = 3,029 ± 4,999 J IC vs. 345 ± 2,863 J IC Sham; p = 0.03) and displayed a greater time to muscle fatigue (Δ = 147 ± 221 s IC vs. -27 ± 236 s IC Sham; p = 0.01).

DISCUSSION/CONCLUSION

In patients with claudication, IC improved total work performed and time to fatigue at the knee but did not change walking parameters.

Peripheral Artery Disease Screening in the Community and 1-Year Mortality, Cardiovascular Events, and Adverse Limb Events

Introduction

This study aimed to examine all-cause mortality, 1- and 2-year major cardiovascular events, and major adverse limb events in individuals aged ≥65 years who received an in-home health visit with peripheral artery disease screening. In addition, we compared 1-year healthcare utilization before and after peripheral artery disease screening for those who screened positive.

Setting/Participants

Medicare Advantage beneficiaries aged ≥65 years participating in the Optum HouseCalls program in the U.S. between April 1, 2017 and February 1, 2019 were included.

Intervention

The intervention consisted of a peripheral artery disease screening program using a plethysmography system.

Main outcome measures

One-year all-cause mortality as a landmark analysis, 1- and 2-year major cardiovascular events, and major adverse limb events after screening were compared by peripheral artery disease screen status using claims data. We compared cardiovascular medications and revascularization procedures between the year before and after the peripheral artery disease screening event for those with peripheral artery disease.

Results

Of 192,500 beneficiaries, 27.7% screened positive. One-year all-cause mortality rates for those who screened positive for peripheral artery disease versus those who screened negative were higher (1.51% vs 0.89%; p<0.001; adjusted hazard ratio=1.21; 95% CI=1.08, 1.36) as well as 1-year major cardiovascular events (5.54% vs 3.60%; adjusted hazard ratio= 1.22; 95% CI=1.15, 1.30) and major adverse limb events (0.23% vs 0.04%; adjusted hazard ratio=3.15; 95% CI=2.10, 4.73). Similar risks were observed for 2-year results. Before and after peripheral artery disease screening, medications remained stable for those who screened positive (e.g., statin therapy=54.2% vs 56.6%); rates of peripheral vascular interventions remained stable (0.0% vs 0.1%).

Conclusions

A national peripheral artery disease screening effort is feasible. Detecting previously undiagnosed peripheral artery disease is a way to risk stratify a population that would benefit from further cardiovascular risk management.

Assessment of endothelial colony forming cells delivery routes in a murine model of critical limb threatening ischemia using an optimized cell tracking approach

Background

Endothelial colony forming cells (ECFCs), alone or in combination with mesenchymal stem cells, have been selected as potential therapeutic candidates for critical limb-threatening ischemia (CLTI), mainly for those patients considered as “no-option,” due to their capability to enhance revascularization and perfusion recovery of ischemic tissues. Nevertheless, prior to translating cell therapy to the clinic, biodistribution assays are required by regulatory guidelines to ensure biosafety as well as to discard undesired systemic translocations. Different approaches, from imaging technologies to qPCR-based methods, are currently applied.

Methods

In the current study, we have optimized a cell-tracking assay based on DiR fluorescent cell labeling and near-infrared detection for in vivo and ex vivo assays. Briefly, an improved protocol for DiR staining was set up, by incubation of ECFCs with 6.67 µM DiR and intensive washing steps prior cell administration. The minimal signal detected for the residual DiR, remaining after these washes, was considered as a baseline signal to estimate cell amounts correlated to the DiR intensity values registered in vivo. Besides, several assays were also performed to determine any potential effect of DiR over ECFCs functionality. Furthermore, the optimized protocol was applied in combination with qPCR amplification of specific human Alu sequences to assess the final distribution of ECFCs after intramuscular or intravenous administration to a murine model of CLTI.

Results

The optimized DiR labeling protocol indicated that ECFCs administered intramuscularly remained mainly within the hind limb muscle while cells injected intravenously were found in the spleen, liver and lungs.

Conclusion

Overall, the combination of DiR labeling and qPCR analysis in biodistribution assays constitutes a highly sensitive approach to systemically track cells in vivo. Thereby, human ECFCs administered intramuscularly to CLTI mice remained locally within the ischemic tissues, while intravenously injected cells were found in several organs. Our data corroborate the need to perform biodistribution assays in order to define specific parameters such as the optimal delivery route for ECFCs before their application into the clinic.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02943-8.

Underutilization of Medical Management of Peripheral Artery Disease Among Patients with Claudication Undergoing Lower Extremity Bypass

OBJECTIVE

First-line treatment of peripheral artery disease (PAD) involves medical therapy and lifestyle modification. Multiple professional organizations such as the Society for Vascular Surgery (SVS) and the American Heart Association/American College of Cardiology (AHA/ACC) make Class I recommendations for medical management including antiplatelet, statin, antihypertensive, and cilostazol medications, as well as lifestyle therapy including exercise and smoking cessation. Although evidence supports up-front medical and lifestyle management prior to surgical intervention, it is unclear how well this occurs in contemporary clinical practice. It is also unclear whether variability in first-line treatment prior to revascularization is associated with postoperative outcomes. This study examined the proportion of patients with claudication actively receiving evidence-based therapy prior to surgery in a statewide surgical registry.

METHODS

We conducted a retrospective cohort study of adult patients undergoing elective open lower extremity bypass for claudication from 2012-2021 within a statewide surgical quality registry. The primary exposure was optimal medical therapy defined as an antiplatelet agent, a statin, and an angiotensin-converting enzyme inhibitors (ACEI) or angiotensin II receptor blockers (ARB) (if the patient had hypertension) on the patient's home medication list on admission for surgery, all of which are Class I recommendations. Despite also being Class I recommendations, cilostazol was not included in the primary exposure due to its highly selective use and our inability to capture intolerance and/or contraindications which are common, and lifestyle therapies were not included as they were only recorded at the time of discharge rather than preoperatively. The primary outcomes were mortality, hospital readmission, amputation, wound complication, myocardial infarction (MI), non-patent bypass, and non-independent ambulatory status at 30 days and 1 year after surgery. Multivariable logistic regression was performed to estimate the association of receiving optimal vs. non-optimal medical therapy.

RESULTS

3,829 patients with claudication underwent bypass surgery during the study period, with a mean age of 64.8 (9.8) years, 2,690 (70.3%) males, and 1,873 (48.9%) current smokers. 1,822 (47.6%) patients were on optimal medical therapy prior to surgery. Additionally, at discharge, 66.5% of smokers received referral to smoking cessation therapy and 54.1% of patients received referral to exercise therapy. In a multivariable logistic regression, compared to patients not on optimal medical therapy, patients on optimal medical therapy prior to surgery had lower 30-day odds of mortality (aOR 0.45 [95% CI 0.26-0.78]) and MI (aOR 0.46 [95% CI 0.28-0.76]) and lower 1-year odds of mortality (aOR 0.57 [95% CI 0.39-0.82]), MI (aOR 0.48 [95% CI 0.32-0.74]), and readmission (aOR 0.79 [95% CI 0.64-0.96]).

CONCLUSION

Although medical and lifestyle management is recommended as first-line treatment for patients with PAD, only half of patients were on optimal medical therapy prior to surgery. Patients receiving optimal therapy had a lower risk of postoperative mortality, MI, and readmission. This suggests that not only are there significant opportunities to improve clinical utilization of evidence-based treatment of PAD, but that doing so can benefit patients postoperatively.

A systematic review of racial/ethnic disparities in pharmacotherapy and surgical treatment outcomes in peripheral arterial disease among African American/non-Hispanic Black, non-Hispanic White and Hispanic patients

Background

Lower extremity peripheral arterial disease (PAD) is associated with significant morbidity and mortality in racial/ethnic diverse populations. However, limited data exist on treatment outcome disparities in racial/ethnic diverse populations, particularly in AA/NHB populations.

Objective

The aim of this systematic review is to analyze disparities in the outcomes of PAD treatments, particularly pharmacotherapy and surgery, among racial/ethnic groups in the US.

Methods

A comprehensive search of original investigations pertaining to PAD treatments between 2015 and 2021 was performed. Quality assessment of the studies was also completed.

Results

Fourteen studies were included. Thirteen studies reported differences in treatment outcomes for surgical intervention, and one study reported differences for concurrent surgical and pharmacotherapy. NHB and Hispanic/Latinx ethnicities were associated with decreased overall and perioperative mortality in four studies. Six studies noted increased amputation risk among racial/ethnic diverse populations. Only one study noted significant survival benefit by race/ethnicity. Three studies noted increased risk of major adverse limb events and post-operative complications. One study noted increased limb patency after intervention in racial/ethnic cohorts. Overall, all studies reported high methodological quality with adequate assessment of outcomes and follow-up of cohort.

Conclusion

In this analysis, the predominant intervention reported is surgical. Overall, racial/ethnic populations are less likely to experience PAD-associated mortality but are more likely to experience adverse events. Further studies are necessary to include all racial/ethnic diverse populations in assessing PAD therapeutic intervention outcomes. Moreover, targeted public health efforts are necessary to increase PAD educational awareness, community-driven risk modification, and patient-centered care planning.

Platelet reactivity testing in peripheral artery disease

DISCLAIMER

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PURPOSE

Oral antiplatelet therapy is routinely used to prevent adverse cardiovascular events in patients with peripheral artery disease (PAD). Several laboratory tests are available to quantify the degree of platelet inhibition following antiplatelet therapy. This article aims to provide a review of the literature surrounding platelet functional testing in patients with PAD receiving oral P2Y12 inhibitors and to offer guidance to clinicians for the use and interpretation of these tests.

SUMMARY

A literature search of PubMed and the Web of Science Core Collection database was conducted. All studies that performed platelet function testing and reported clinical outcomes in patients with PAD were included. Evaluation of the data suggests that, among the available testing strategies, the VerifyNow platelet reactivity unit (PRU) test is the most widely used. Despite numerous investigations attempting to define a laboratory threshold indicating suboptimal response to antiplatelet therapy, controversy exists about which PRU value best correlates with cardiovascular outcomes (ie, mortality, stent thrombosis, etc). In the PAD literature, the most commonly used PRU thresholds are 208 or higher and 235 or higher. Nonetheless, adjusting antiplatelet regimens based on suboptimal P2Y12 reactivity values has yet to be proven useful in reducing the incidence of adverse cardiovascular outcomes. This review examines platelet function testing in patients with PAD and discusses the interpretation and application of these tests when monitoring the safety and efficacy of P2Y12 inhibitors.

CONCLUSION

Although platelet functional tests may be simple to use, clinical trials thus far have failed to show benefit from therapy adjustments based on test results. Clinicians should be cautioned against relying on this test result alone and should instead consider a combination of laboratory, clinical, and patient-specific factors when adjusting P2Y12 inhibitor therapy in clinical practice.

Correlation of Serum CysC, IMA, and LP-PLA2 Levels With Type 2 Diabetes Mellitus Patients With Lower Extremity Atherosclerotic Occlusive Disease

Objective

To investigate the serum level of cystatin C (CysC), ischemia-modified albumin (IMA), and lipoprotein-associated phospholipase A2 (LP-PLA2) in patients with type 2 diabetes mellitus (T2DM) and with lower extremity atherosclerotic occlusive disease (LEASOD) and their correlation.

Methods

From March 2017 to December 2019, 110 patients with T2DM with LEASOD, who were treated in our hospital, were selected as the observation group. One hundred ten healthy persons who received medical examination in our hospital during the same period were selected as the control group. Serum CysC, IMA, LP-PLA2, and ankle-brachial index (ABI) were detected in each group. According to the ABI index, the observation group was divided into three subgroups, namely, the mild group (n = 45), the moderate group (n = 42), and the severe group (n = 23). Pearson correlation analysis was used to analyze the relationship between serum CysC, IMA, and LP-PLA2 levels in patients with T2DM with LEASOD and their condition. The receiver operator characteristic (ROC) curve was used to analyze the diagnostic value of serum CysC, IMA, and LP-PLA2 levels in patients with T2DM with LEASOD.

Results

The serum levels of CysC, IMA, and LP-PLA2 in the observation group were higher than those in the control group (p < 0.05). The serum levels of CysC, IMA, and LP-PLA2 in the severe and the moderate group were higher than those in the mild group, and the serum levels of CysC, IMA, and LP-PLA2 in the severe group were higher than those in the moderate group (p < 0.05). Pearson correlation analysis showed that CysC, IMA, and LP-PLA2 levels were all negatively correlated with ABI (r = −0.802, r = −0.757, r = −0.764, p < 0.001). The ROC curve results showed that the area under the curve (AUC) of serum CysC in the diagnosis of T2DM with LEASOD was 0.806, and the best cut-off value was 1.74 mg/L. The AUC of serum IMA for diagnosis of T2DM with LEASOD was 0.772, and the best cut-off value was 92.58 g/L. The AUC of serum LP-PLA2 in the diagnosis of T2DM with LEASOD was 0.781, and the best cut-off value was 544.86 ng/L. The AUC of the three combined diagnoses of T2DM with LEASOD was 0.863.

Conclusion

Serum levels of CysC, IMA, and LP-PLA2 were increased in patients with T2DM with LEASOD. Serum CysC, IMA, and LP-PLA2 are closely related to the severity of the disease. The higher the serum levels of CysC, IMA, and LP-PLA2, the more serious the degree of lower extremity arteriosclerosis occlusion, which can be used as an important serum marker to monitor the severity of T2DM with LEASOD. The combined detection of serum CysC, IMA, and LP-PLA2 has good diagnostic value for patients with T2DM with LEASOD.

Reporting Peripheral Artery Disease in Claudicants: Lessons Learned From the TASC-Ability Study

BACKGROUND

The Trans-Atlantic Inter-Society Consensus Document (TASC II) aims to comprehensively describe the case scenarios of aortoiliac and femoropopliteal lesions to suggest an endovascular or a surgical approach. Over time, it has become a guide for describing the gravity of arterial lesions.

PURPOSE

To assess the revised TASC II system for classifying arterial lesions in a large database of patients presenting with claudication.

MATERIALS AND METHODS

This study was a retrospective review of the arteriograms of patients with intermittent claudication. Aortoiliac and femoropopliteal lesions were classified according to the TASC II. When no consensus was reached, the lesion was rated as unTASCable.

RESULTS

In total, 1454 patients were included (male: 62.1%, 66.8±9.3 years). There were 39% aortoiliac lesions (n=960/2462) and 61% femoropopliteal lesions (n=1502/2462); 33.6% of the patients (n=489/1454) were associated with aortoiliac and femoropopliteal lesions. In addition, 20% of the lesions (n=493/2462) were unTASCable, and 26.7% of the patients (n=388/1454) had at least 1 unTASCable lesion. There were 4 categories of unTASCable lesions: (1) association with a common femoral artery lesion in 53.1% (n=262/493); (2) iliac artery lesions in 23.1% (n=114/493); (3) femoropopliteal lesions whose lengths did not fit into any category in 16.6% (n=82/493); and (4) association with an aortic lesion in 7.1% (n=35/493). The interobserver agreement was 0.97 for anatomically describing the infrarenal arterial tree and 0.85 for TASCing, with the lesions lowering to 0.69 for aortoiliac lesions.

CONCLUSION

Using the revised TASC II case scenario, 26.7% of the patients had at least 1 unTASCable lesion. Reporting peripheral artery disease using a comprehensive anatomical description of the infrarenal arterial tree showed better interobserver reproducibility.

Elevated C-Reactive Protein/Albumin Ratio Is Associated With Lesion Complexity, Multilevel Involvement, and Adverse Outcomes in Patients With Peripheral Artery Disease

Inflammation plays an important role in the progression of peripheral artery disease (PAD). We investigated the predictive value of the C-reactive protein-to-albumin ratio (CAR) on the severity of PAD and outcomes after endovascular therapy (EVT). Patients (n = 307) with PAD who underwent EVT were retrospectively reviewed and categorized according to CAR tertiles. The groups were compared for the prevalence of complex lesions and multilevel involvement as well as the incidence of major adverse cardiovascular events (MACEs) and major adverse limb events (MALEs). The rates of complex lesions and multilevel involvement increased with increasing CAR tertiles (all P < .001). These associations remained significant even after adjustment for other confounders (complex lesion odds ratio, 1.22 [1.03-1.50]; P = .036; multilevel disease odds ratio, 1.20 [1.01-1.44]; P = .041). The third CAR tertile showed a significantly higher incidence of MACEs and MALEs than the second and first tertiles within a year (log-rank P < .001). A higher CAR as a continuous variable was also independently associated with the 4-year rate of MACE (hazard ratio, 1.20 [1.04-1.38]; P = .015). Elevated CAR was a powerful surrogate marker of severe PAD and worse outcomes. Thus, CAR might become a predictor of poor prognosis in patients with PAD.

Modulation of Mesenchymal Stem Cells for Enhanced Therapeutic Utility in Ischemic Vascular Diseases

Mesenchymal stem cells are multipotent stem cells isolated from various tissue sources, including but not limited to bone marrow, adipose, umbilical cord, and Wharton Jelly. Although cell-mediated mechanisms have been reported, the therapeutic effect of MSCs is now recognized to be primarily mediated via paracrine effects through the secretion of bioactive molecules, known as the “secretome”. The regenerative benefit of the secretome has been attributed to trophic factors and cytokines that play neuroprotective, anti-angiogenic/pro-angiogenic, anti-inflammatory, and immune-modulatory roles. The advancement of autologous MSCs therapy can be hindered when introduced back into a hostile/disease environment. Barriers include impaired endogenous MSCs function, limited post-transplantation cell viability, and altered immune-modulatory efficiency. Although secretome-based therapeutics have gained popularity, many translational hurdles, including the heterogeneity of MSCs, limited proliferation potential, and the complex nature of the secretome, have impeded the progress. This review will discuss the experimental and clinical impact of restoring the functional capabilities of MSCs prior to transplantation and the progress in secretome therapies involving extracellular vesicles. Modulation and utilization of MSCs–secretome are most likely to serve as an effective strategy for promoting their ultimate success as therapeutic modulators.

Prescribing of Statins After Lower Extremity Revascularization Procedures in the US

IMPORTANCE

The use of statins in patients with symptomatic peripheral artery disease remains suboptimal despite strong clinical practice guideline recommendations; however, it is unknown whether rates are associated with substantial improvements after lower extremity revascularization.

OBJECTIVE

To report longitudinal trends of statin use in patients with peripheral artery disease undergoing lower extremity revascularization and to identify the clinical and procedural characteristics associated with prescriptions for new statin therapy at discharge.

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective cross-sectional study using data from the Vascular Quality Initiative registry of patients who underwent lower extremity peripheral artery disease revascularization from January 1, 2014, through December 31, 2019. The Vascular Quality Initiative is a multicenter registry database including academic and community-based hospitals throughout the US. Patients aged 18 years or older undergoing lower extremity revascularization with available statin data (preprocedure and postprocedure) were included. Those not receiving statin therapy for medical reasons were excluded from final analyses.

EXPOSURES

Patients undergoing lower extremity revascularization for whom statin therapy is indicated.

MAIN OUTCOMES AND MEASURES

Multivariate logistic regression was used to determine the clinical and procedural characteristics associated with new statin prescription for patients not already taking a statin preprocedure. The overall rates of statin prescription as well as rates of new statin prescription at discharge were determined. In addition, the clinical, demographic, and procedural characteristics associated with new statin prescription were analyzed.

RESULTS

There were 172 025 procedures corresponding to 125 791 patients (mean [SD] age, 67.7 [11.0] years; 107 800 men [62.7%]; and 135 405 White [78.7%]) included in the analysis. Overall rates of statin prescription at discharge improved from 17 299 of 23 093 (75%) in 2014 to 29 804 of 34 231 (87%) in 2019. However, only 12 790 of 42 020 patients (30%) not already taking a statin at the time of revascularization during the study period were newly discharged with a statin medication. New statin prescription rates were substantially lower after endovascular intervention (7745 of 29 581 [26%]) than after lower extremity bypass (5045 of 12 439 [41%]). Body mass index of 30 or greater (odds ratio [OR], 1.13; 95% CI, 1.04-1.24; P < .001), diabetes (diet-controlled vs no diabetes, OR, 1.22; 95% CI, 1.05-1.41; P = .01), smoking (current vs never, OR, 1.32; 95% CI, 1.21-1.45; P < .001), hypertension (OR, 1.19; 95% CI, 1.09-1.29; P < .001), and coronary heart disease (OR, 1.26; 95% CI, 1.17-1.35; P < .001) were associated with an increased likelihood of new statin prescription after endovascular intervention, whereas female sex, older age, antiplatelet use, and prior peripheral revascularization were associated with a decreased likelihood.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, although statin use was associated with a substantial improvement after lower extremity revascularization, more than two-thirds of patients not already taking a statin preprocedure remained not taking a statin at discharge. Further investigations to understand the clinical implications of these findings and develop clinician- and system-based interventions are needed.

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.

Life-style counseling program and supervised exercise improves walking distance and quality of life in patients with intermittent claudication

INTRODUCTION

There are many barriers for patients with intermittent claudication (IC) to complete and maintain the supervised exercise therapy (SET) programs. SET combined with life-style counseling was, therefore, investigated.

OBJECTIVE

This study aimed to report the experience of a single center where SET and life-style counseling targeting the modification of risk factors to treat IC, improved walking distance and quality of life.

METHODS

Thirty-five patients out of 62 referred patients with IC completed the full program of 12 weeks SET and 12 weeks self-training combined with counseling focusing in modifying the risk factors. The pain free walking distance (PFWD) and maximum walking distance (MWD) were measured as primary outcomes. Vascular Quality of Life Questionnaire 6 (VascuQoL-6) and 6-min walk test (6-MWT) were measured as secondary outcomes. Analysis of variance and last value carried forward method was used to compare the outcomes.

RESULTS

Fifteen females and 20 males with mean age of 71.5 years completed the program. PFWD and MWD increased by 116% (P < .001) and 120% (P < .001), respectively, at 24 weeks follow-up. Similarly, there was 14% increase in 6-MWT and VascuQoL-6 overall score increased from 13.1 to 15.9 at 24 week follow-up (P < .001).

CONCLUSION

SET along with life-style counseling can be considered as a package in the treatment of patients with IC.

Trends in Use of Cardioprotective Medication in Peripheral Artery Disease: A Nationwide Study

Background

Guideline‐based cardioprotective medical therapy is intended to reduce the burden of adverse cardiovascular and limb outcomes in patients with peripheral artery disease (PAD). However, contemporary data describing trends in use of medication remains limited. The present study, therefore, aims to investigate changes in use of cardioprotective medication in PAD.

Methods and Results

By using Danish national healthcare registries, we identified all patients with first‐time diagnosis of PAD (1997–2016) and classified them into two groups: (1) PAD+ that includes all patients with PAD with a history of cardiovascular disease, ie, myocardial infarction, atrial fibrillation, and stroke (n=162 627); and (2) PAD (n=87 935) that comprise patients without a history of cardiovascular disease. We determined the use of medication in the first 12 months after the incident diagnosis of PAD and estimated age standardized 1‐year mortality rates. Our results showed increase in use of cardioprotective medication throughout the study period in both groups. However, PAD+ had a higher use of medication (acetylsalicylic acid, 3.5%–48.4%; Clopidogrel, 0%–17.6%; vitamin K antagonists, 0.9%–7.8%; new oral anticoagulants, 0.0%–10.1%; Statins, 1.9%–58.1%; angiotensin‐converting enzyme inhibitors, 1.2%–20.6%), compared with PAD (acetylsalicylic acid, 2.9%–54.4%; Clopidogrel, 0%–11.9%; vitamin K antagonists, 0.9%–2.4%; new oral anticoagulants, 0.0%–3.4%; Statins, 1.5%–56.9%; angiotensin‐converting enzyme, 0.9%–17.2%), respectively. Furthermore, 1‐year mortality rates in PAD declined with increased use of medications during study.

Conclusions

In this nationwide study, use of cardioprotective medication increased considerably with time, but compared to patients with other atherosclerotic diseases, there remains an underuse of guideline‐based medical therapy in patients with PAD.

Long-term results of the Japanese multicenter Viabahn trial of heparin bonded endovascular stent grafts for long and complex lesions in the superficial femoral artery

OBJECTIVE

To assess the long-term safety and efficacy of endovascular stent grafting to treat long, complex lesions in the superficial femoral artery (SFA).

METHODS

This prospective, multicenter study at 15 Japanese hospitals assessed heparin bonded stent grafts for treating long SFA lesions in patients with symptomatic peripheral arterial disease. Inclusion criteria were Rutherford category 2-5 symptoms (grade 5 without active infection), ankle-brachial index (ABI) ≤ 0.9, and SFA lesions ≥ 10 cm with ≥ 50% stenosis. The key efficacy and safety outcomes were primary-assisted patency (PAP) and adverse events through 24 months, respectively. Secondary outcomes included primary patency (PP), secondary patency, freedom from target lesion revascularization (fTLR), and VascuQOL scoring.

RESULTS

Of 103 subjects (mean age 74.2 ± 7.0 years; 82.5% male), 100 (97.1%) had intermittent claudication. Average lesion length was 21.8 ± 5.8 cm; 87 lesions (84.5%) were TASC C/D classification (65.7% chronic total occlusions). Ninety-two subjects and 61 subjects were evaluable through 24 months and 60 months, respectively. At 24 months, the Kaplan-Meier-estimated PAP rate was 85.7% (95% CI: 76.3‒91.5%), PP rate was 78.8% (95% CI: 68.8‒85.9%), and secondary patency rate was 92.0% (95% CI: 82.4-96.5%). Mean ABI was 0.64 ± 0.12 at baseline and 0.94 ± 0.19 at 24 months (P<.0001). At 24 months, fTLR was 87.2% (95% CI: 78.9-92.3%), and at 60 months, fTLR was 79.1% (95% CI: 67.9-86.8%). No device or procedure-related life- or limb-threatening critical events or acute limb ischemia cases were observed through 5 years. No stent fractures were detected in annually scheduled follow-up x-rays. Scores from the VascuQOL and Walking Impairment Questionnaire were significantly increased at 1 month through 24 months versus baseline values (P<.0001 for both). One subject was converted to open bypass through 5 years.

CONCLUSIONS

Stent grafting of long and complex SFA lesions in claudicant patients is safe and effective through long-term follow-up, with 79.1% fTLR and no study leg amputation, acute limb ischemia, or stent fractures through 5 years.

Current Status of Angiogenic Cell Therapy and Related Strategies Applied in Critical Limb Ischemia

Critical limb ischemia (CLI) constitutes the most severe form of peripheral arterial disease (PAD), it is characterized by progressive blockade of arterial vessels, commonly correlated to atherosclerosis. Currently, revascularization strategies (bypass grafting, angioplasty) remain the first option for CLI patients, although less than 45% of them are eligible for surgical intervention mainly due to associated comorbidities. Moreover, patients usually require amputation in the short-term. Angiogenic cell therapy has arisen as a promising alternative for these "no-option" patients, with many studies demonstrating the potential of stem cells to enhance revascularization by promoting vessel formation and blood flow recovery in ischemic tissues. Herein, we provide an overview of studies focused on the use of angiogenic cell therapies in CLI in the last years, from approaches testing different cell types in animal/pre-clinical models of CLI, to the clinical trials currently under evaluation. Furthermore, recent alternatives related to stem cell therapies such as the use of secretomes, exosomes, or even microRNA, will be also described.

REX-001, a BM-MNC Enriched Solution, Induces Revascularization of Ischemic Tissues in a Murine Model of Chronic Limb-Threatening Ischemia

Background: Bone Marrow Mononuclear Cells (BM-MNC) constitute a promising alternative for the treatment of Chronic Limb-Threatening ischemia (CLTI), a disease characterized by extensive blockade of peripheral arteries, clinically presenting as excruciating pain at rest and ischemic ulcers which may lead to gangrene and amputation. BM-MNC implantation has shown to be efficient in promoting angiogenesis and ameliorating ischemic symptoms in CLTI patients. However, the variability seen between clinical trials makes necessary a further understanding of the mechanisms of action of BM-MNC, and moreover, to improve trial characteristics such as endpoints, inclusion/exclusion criteria or drug product compositions, in order to implement their use as stem-cell therapy.

Materials: Herein, the effect of REX-001, a human-BM derived cell suspension enriched for mononuclear cells, granulocytes and CD34+ cells, has been assessed in a murine model of CLTI. In addition, a REX-001 placebo solution containing BM-derived red blood cells (BM-RBCs) was also tested. Thus, 24 h after double ligation of the femoral artery, REX-001 and placebo were administrated intramuscularly to Balb-c nude mice (n:51) and follow-up of ischemic symptoms (blood flow perfusion, motility, ulceration and necrosis) was carried out for 21 days. The number of vessels and vascular diameter sizes were measured within the ischemic tissues to evaluate neovascularization and arteriogenesis. Finally, several cell-tracking assays were performed to evaluate potential biodistribution of these cells.

Results: REX-001 induced a significant recovery of blood flow by increasing vascular density within the ischemic limbs, with no cell translocation to other organs. Moreover, cell tracking assays confirmed a decrease in the number of infused cells after 2 weeks post-injection despite on-going revascularization, suggesting a paracrine mechanism of action.

Conclusion: Overall, our data supported the role of REX-001 product to improve revascularization and ischemic reperfusion in CLTI.

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.

The Society for Vascular Surgery Alternative Payment Model Task Force report on opportunities for value-based reimbursement in care for patients with peripheral artery disease

The Society for Vascular Surgery Alternative Payment Model (APM) Taskforce document explores the drivers and implications for developing objective value-based reimbursement plans for the care of patients with peripheral arterial disease (PAD). The APM is a payment approach that highlights high-quality and cost-efficient care and is a financially incentivized pathway for participation in the Quality Payment Program, which aims to replace the traditional fee-for-service payment method. At present, the participation of vascular specialists in APMs is hampered owing to the absence of dedicated models. The increasing prevalence of PAD diagnosis, technological advances in therapeutic devices, and the increasing cost of care of the affected patients have financial consequences on care delivery models and population health. The document summarizes the existing measurement methods of cost, care processes, and outcomes using payor data, patient-reported outcomes, and registry participation. The document also evaluates the existing challenges in the evaluation of PAD care, including intervention overuse, treatment disparities, varied clinical presentations, and the effects of multiple comorbid conditions on the cost potentially attributable to the vascular interventionalist. Medicare reimbursement data analysis also confirmed the prolonged need for additional healthcare services after vascular interventions. The Society for Vascular Surgery proposes that a PAD APM should provide patients with comprehensive care using a longitudinal approach with integration of multiple key medical and surgical services. It should maintain appropriate access to diagnostic and therapeutic advancements and eliminate unnecessary interventions. It should also decrease the variability in care but must also consider the varying complexity of the presenting PAD conditions. Enhanced quality of care and physician innovation should be rewarded. In addition, provisions should be present within an APM for high-risk patients who carry the risk of exclusion from care because of the naturally associated high costs. Although the document demonstrates clear opportunities for quality improvement and cost savings in PAD care, continued PAD APM development requires the assessment of more granular data for accurate risk adjustment, in addition to largescale testing before public release. Collaboration between payors and physician specialty societies remains key.

Effect of Target Lesion Revascularization on Restenosis Lesions of the Superficial Femoral Artery without Recurred Symptoms after Endovascular Therapy

Aim: This study aims to elucidate the effects of early application of target lesion revascularization (TLR) to restenosis lesions of the superficial femoral artery (SFA) without recurrence of symptoms. Despite recent improvements in endovascular therapy (EVT) for the SFA, restenosis remains to be a problem. However, restenosis is not always associated with the recurrence of limb symptoms. Although early application of TLR is not generally approved for restenosis lesions of the SFA without recurred symptoms, it is expected to contribute to long-term patency and other favorable outcomes. Nonetheless, its effectiveness remains to be determined.

Methods: We retrospectively analyzed 616 patients who developed restenosis after undergoing femoro-popliteal EVT for claudication (Rutherford category 1 to 3) due to de novo femoro-popliteal lesions between January 2010 and December 2016 at 11 centers in Japan. Recurred symptoms were defined as symptoms of the same or higher Rutherford categories than those immediately before the initial EVT.

Results: Of the patients, 291 (47 %) lacked recurred symptoms; 69 (24 %) underwent TLR for restenosis. After propensity matching, the risk of occlusion was determined to be not significantly different between the TLR and observation groups; the 3-year occlusion-free rate was 68 % and 62 %, respectively (P=0.84). The risk of recurring symptoms, critical limb ischemia, and all-cause death was also found to be comparable between groups. The incidence of target vessel revascularization was significantly higher in the TLR than in the observation group (1.55 [95 % confidence interval: 1.25–1.93] vs. 0.59 [0.41–0.85] per 3 person-years).

Conclusions: In patients with SFA restenosis without recurred symptoms, early application of TLR showed no advantages.

Literature review and meta-analysis of the efficacy of cilostazol on limb salvage rates after infrainguinal endovascular and open revascularization

BACKGROUND

Current clinical guidelines recommend the use of cilostazol in the treatment of patients with infrainguinal peripheral artery disease (PAD) who experience intermittent claudication. However, the role of cilostazol therapy in patients with advanced PAD and critical limb ischemia (CLI) remains unclear. To conduct a meta-analysis of randomized controlled trials and cohort studies that evaluated the effect of cilostazol vs standard antiplatelet therapy on limb-related and arterial patency-related outcomes. We also reviewed literature pertinent to the effect of cilostazol on wound healing in patients with advanced PAD.

METHODS

We performed a MEDLINE, EMBASE, COCHRANE (CENTRAL), SCOPUS, and US Clinical Trials database search for all trials and studies since 1999 that compared cilostazol with standard antiplatelet therapy in the setting of infrainguinal PAD revascularization procedures (endovascular or open). Aggregate data was collected from four randomized control trials and six retrospective cohort studies. The end point incidence ratios and treatment effects were generated from each study and reported as hazard ratios (HR) using a random-effect model. We also reviewed 10 studies that evaluated the effect of cilostazol on wound healing in patients with advanced PAD.

RESULTS

From more than 25,000 total patients, 3136 patients met our inclusion criteria. All patients had at least lifestyle-impacting intermittent claudication, and more than 50% met the definition of CLI (Rutherford class ≥4). Patient age range was 53 to 83 years, and the majority were male (66%). The mean follow-up time averaged 2 years across all studies. Meta-analysis revealed that cilostazol treatment favored amputation-free survival (hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.69-0.91), limb salvage rate (HR, 0.42; 95% CI, 0.27-0.66), decreased repeat revascularization (risk ratio [RR], 0.44; 95% CI, 0.37-0.52), and decreased restenosis (RR, 0.68; 95% CI, 0.61-0.76). Cilostazol treatment also increased freedom from target lesion revascularization (RR, 1.35; 95% CI, 1.21-1.53) with no difference in all-cause mortality. Effective wound healing was found to be an inconsistent outcome measure in patients receiving cilostazol therapy.

CONCLUSIONS

We observed that cilostazol therapy has a beneficial impact on all limb-related and arterial patency-related outcomes, but no effect on all-cause mortality in patients with advanced PAD and CLI undergoing revascularization procedures. Additional studies are needed to evaluate the effect of cilostazol therapy on wound healing in patients with advanced PAD.

Immediate postoperative hyperglycemia after peripheral arterial bypass is associated with short-term and long-term poor outcomes

OBJECTIVE

Although the impact of poorly controlled diabetes on surgical outcomes of patients undergoing lower extremity revascularization is well-known, it is not clear if immediate postoperative hyperglycemia (IPH) itself can be used as a surrogate for poor outcomes after peripheral arterial bypass. We sought to examine the effect of IPH in this patient population with its impact on short-term and long-term outcomes.

METHODS

Retrospective review was completed for 505 patients who underwent either suprainguinal bypass surgery or infrainguinal bypass surgery between July 2002 and April 2018 for the treatment of peripheral arterial disease. All patients were undergoing first-time open bypass grafting. Patients were stratified into those who were normoglycemic or hyperglycemic (glucose ≥ 140 mg/dL) within 24 hours after surgery. A comparative analysis was performed on comorbidities and outcomes.

RESULTS

Of 505 patients who underwent bypass grafting, 255 patients (50.5%) were hyperglycemic. The mean age of patients was 63.5 ± 14.1 years. The median follow-up was 5.2 years (range, 0.0-15.2 years). The distribution of procedures was as follows: femoral to popliteal bypasses (29%), femoral to femoral bypasses (17%), femoral to tibial bypasses (12%), aortobifemoral bypasses (10%), iliofemoral bypasses (9%), and axillofemoral bypasses (7%). At 30 days, hyperglycemic patients had an increased incidence of limb loss (8.3% vs 4.0%) and myocardial infarction (4.8% vs 0.8%) and incurred higher costs of hospital stay ($27,701 vs $22,990) (all P < .05). At 10 years, these patients had a higher incidence of needing major amputations (15.4% vs 9.4%; P = .025). Hyperglycemia after infrainguinal bypass was associated with nearly twice the risk of limb loss at 5 years (hazard ratio, 1.91; P = .034). Among the cohort of patients who required major amputations, the time duration between index revascularization and amputation was significantly shorter as compared with normoglycemic patients (P = .003).

CONCLUSIONS

In this single-institution study with long-term follow-up, IPH was associated with increased rates of 30-day amputation and myocardial infarction, as well as an increased cost of hospital stay. In the long term, postoperative hyperglycemia was associated with greater major limb loss. Among the cohort of patients who required major amputations, the time period between revascularization and amputation was shorter for those patients who had IPH. IPH is an independent marker for poor outcomes after lower extremity revascularization procedures.

Fibrosis and Inflammatory Markers and Long-Term Risk of Peripheral Artery Disease: The ARIC Study

OBJECTIVE

Inflammatory markers, such as hs-CRP (high-sensitivity C-reactive protein), have been reported to be related to peripheral artery disease (PAD). Galectin-3, a biomarker of fibrosis, has been linked to vascular remodeling and atherogenesis. However, its prospective association with incident PAD is unknown; as is the influence of inflammation on the association between galectin-3 and PAD. Approach and Results: In 9851 Atherosclerosis Risk in Communities Study participants free of PAD at baseline (1996-1998), we quantified the association of galactin-3 and hs-CRP with incident PAD (hospitalizations with PAD diagnosis [International Classification of Diseases-Ninth Revision: 440.2-440.4] or leg revascularization [eg, International Classification of Diseases-Ninth Revision: 38.18]) as well as its severe form, critical limb ischemia (PAD cases with resting pain, ulcer, gangrene, or leg amputation) using Cox models. Over a median follow-up of 17.4 years, there were 316 cases of PAD including 119 critical limb ischemia cases. Log-transformed galectin-3 was associated with incident PAD (adjusted hazard ratio, 1.17 [1.05-1.31] per 1 SD increment) and critical limb ischemia (1.25 [1.05-1.49] per 1 SD increment). The association was slightly attenuated after further adjusting for hs-CRP (1.14 [1.02-1.27] and 1.22 [1.02-1.45], respectively). Log-transformed hs-CRP demonstrated robust associations with PAD and critical limb ischemia even after adjusting for galectin-3 (adjusted hazard ratio per 1 SD increment 1.34 [1.18-1.52] and 1.34 [1.09-1.65], respectively). The addition of galectin-3 and hs-CRP to traditional atherosclerotic predictors (C statistic of the base model 0.843 [0.815-0.871]) improved the risk prediction of PAD (ΔC statistics, 0.011 [0.002-0.020]).

CONCLUSIONS

Galectin-3 and hs-CRP were independently associated with incident PAD in the general population, supporting the involvement of fibrosis and inflammation in the pathophysiology of PAD.

Quality Indicators in Vascular Surgery: Toward a National Consensus on 20 Quality Indicators in Belgium

BACKGROUND

The aim of the present study is to develop relevant quality indicators (QI) to monitor and improve quality of care in vascular surgery.

METHODS

The Delphi method was used to incorporate expert opinion to reach consensus on a set of QI. A national expert panel consisting of 52 vascular surgeons was installed on a voluntary basis and endorsed by the Belgian Society of Vascular Surgery and the Flemish Hospital Network KU Leuven. A task force team consisting of 12 surgeons was created to serve as a delegation of the expert panel to discuss and filter the obtained data from the different Delphi rounds.

RESULTS

A total of 3 Delphi rounds were needed to reach consensus on a set of 20 QI. Each QI had a content validity index (using a 7-point Likert scale), a feasibility index, and a target level. Twelve outcome indicators and 8 process indicators on several vascular topics were selected: overall for all vascular treatments (n = 1), arterial occlusive disease in general (n = 3), arterial occlusive disease of the lower limbs (n = 4), arterial occlusive disease of the carotid arteries (n = 5), arterial aneurysm disease in general (n = 2), arterial aneurysm disease with endovascular treatment (n = 1), and venous disease (n = 4).

CONCLUSIONS

This resulted in the successful identification of 20 validated and relevant vascular QI, focusing on arterial occlusive disease, arterial aneurysm disease, and venous disease. The next step in this project will be the performance of an implementation study.

Identification of the initial molecular changes in response to circulating angiogenic cells-mediated therapy in critical limb ischemia

Background

Critical limb ischemia (CLI) constitutes the most aggressive form of peripheral arterial occlusive disease, characterized by the blockade of arteries supplying blood to the lower extremities, significantly diminishing oxygen and nutrient supply. CLI patients usually undergo amputation of fingers, feet, or extremities, with a high risk of mortality due to associated comorbidities.

Circulating angiogenic cells (CACs), also known as early endothelial progenitor cells, constitute promising candidates for cell therapy in CLI due to their assigned vascular regenerative properties. Preclinical and clinical assays with CACs have shown promising results. A better understanding of how these cells participate in vascular regeneration would significantly help to potentiate their role in revascularization.

Herein, we analyzed the initial molecular mechanisms triggered by human CACs after being administered to a murine model of CLI, in order to understand how these cells promote angiogenesis within the ischemic tissues.

Methods

Balb-c nude mice (n:24) were distributed in four different groups: healthy controls (C, n:4), shams (SH, n:4), and ischemic mice (after femoral ligation) that received either 50 μl physiological serum (SC, n:8) or 5 × 10⁵ human CACs (SE, n:8). Ischemic mice were sacrificed on days 2 and 4 (n:4/group/day), and immunohistochemistry assays and qPCR amplification of Alu-human-specific sequences were carried out for cell detection and vascular density measurements. Additionally, a label-free MS-based quantitative approach was performed to identify protein changes related.

Results

Administration of CACs induced in the ischemic tissues an increase in the number of blood vessels as well as the diameter size compared to ischemic, non-treated mice, although the number of CACs decreased within time. The initial protein changes taking place in response to ischemia and more importantly, right after administration of CACs to CLI mice, are shown.

Conclusions

Our results indicate that CACs migrate to the injured area; moreover, they trigger protein changes correlated with cell migration, cell death, angiogenesis, and arteriogenesis in the host. These changes indicate that CACs promote from the beginning an increase in the number of vessels as well as the development of an appropriate vascular network.

Graphical abstract

Poor glycemic control is associated with significant increase in major limb amputation and adverse events in the 30-day postoperative period after infrainguinal bypass

OBJECTIVE

Understanding modifiable risk factors to improve surgical outcomes is increasingly important in value-based health care. There is an established association between peripheral artery disease (PAD), diabetes, and limb loss, but less is known about expected outcomes after revascularization relative to the degree of glycemic control. The purpose of this study was to determine the association between hemoglobin A_1c (HbA_1c) management in diabetics and surgical outcomes after open infrainguinal bypass.

METHODS

The Vascular Quality Initiative infrainguinal bypass module was used to identify adult patients (≥18 years) with a history of diabetes who underwent bypass for PAD between 2011 and 2018. Exclusion criteria included missing or illogical HbA_1c values and if the indication for the limb treated was not PAD. Patients were categorized by preoperative HbA_1c levels as low severity/controlled (<7.0%), high severity (7.0%-10.0%), and very high severity (>10.0%). Primary outcomes were 30-day incidence of major adverse cardiac events (MACEs), major adverse limb events (MALEs), ipsilateral amputation, and 1-year all-cause mortality. Thirty-day outcomes were calculated using multivariable regression to compute odds ratios; hazard ratios were calculated for all-cause mortality. All analyses were adjusted for demographics, comorbidities, and clinical characteristics.

RESULTS

The final sample included 30,813 operations (27,988 unique patients): 17,517 (57%) nondiabetic patients, 5194 patients with low-severity/controlled diabetes, and 8102 (26%) patients with poorly controlled diabetes, including 5531 (70%) treated with insulin. There were 6439 (21%) patients with high-severity HbA_1c values and 1663 (5%) patients with very-high-severity HbA_1c values. Those with a very high HbA_1c level were more likely to be nonwhite, insulin dependent, and active smokers. Compared with nondiabetics, patients with very-high-severity HbA_1c had an 81% increase in MACEs and 31% increase in MALEs, whereas patients with high-severity HbA_1c only had a 49% increase in MACEs and a 12% increase in MALEs. Each one-step increase in severity category (eg, low to high to very high) was associated with an average 29% increase in the odds of MACEs and an 8% increase in the odds of MALEs.

CONCLUSIONS

Uncontrolled diabetes with an HbA_1c value >10.0% was associated with significantly worse 30-day surgical outcomes. Patients with incrementally better glycemic control (HbA_1c level of 7.0%-10.0%) did not suffer the same rate of complications, suggesting that preoperative attempts at improving diabetes management even slightly could lead to improved surgical outcomes in open infrainguinal bypass patients.

Intravascular Lithotripsy for Treatment of Calcified, Stenotic Iliac Arteries: A Cohort Analysis From the Disrupt PAD III Study

PURPOSE

The presence of calcification in the iliac arteries is associated with decreased procedural success and increased complication risk during endovascular intervention. The objective of this study was to evaluate the safety and efficacy of peripheral intravascular lithotripsy (IVL) during endovascular treatment of iliac arterial peripheral artery disease (PAD).

METHODS

The Disrupt PAD III Observational Study is a prospective, non-randomized, multi-center single-arm study to assess the 'real-world' safety and effectiveness of the Shockwave Peripheral IVL System for the treatment of de novo calcified lesions in the peripheral arteries, with a goal of treating 1500 patients. This is an analysis of consecutive patients enrolled for treatment of an iliac artery, a specified sub-group, with at least moderate calcification and a minimum length of 20 mm.

RESULTS

Between December 2017 and July 2019, 118 patients with a total of 200 lesions were enrolled across 20 sites. 101 patients were treated primarily for claudication or critical limb ischemia, while 17 patients were treated to optimize the iliac vasculature for large-bore access. All 118 patients had successful IVL catheter delivery. The average reference vessel diameter was 7.3 mm ± 1.9 mm, with an average diameter stenosis of 83.1% ± 13.4% and an average lesion length of 58.3 mm ± 57.6 mm. Severe calcification was present in 82.0% of overall cases. Stent placement was performed in 72.9% of the overall cases. As expected, the access group received less adjunctive therapies including stents (41.2%, p < 0.001). Angiographic complications were minimal with no flow-limiting dissections and a final mean residual stenosis of 12.0% ± 12.1% with no differences between the groups.

CONCLUSIONS

Acute results with IVL in calcified iliac lesions suggest that it is a safe and effective option for calcified, stenotic iliac disease. IVL can be used successfully both for treatment of PAD symptoms and to optimize access for large-bore procedures.

[Do the patients with peripheral atherosclerosis need to a medical therapy before the revascularization?]

In the review article are provided the approaches to the therapy for improvement of prognosis in patients with peripheral and multifocal atherosclerosis which are available now; some limitations and a real situation are designated for the antithrombotic therapy in this category of patients. According to the clinical trial COMPASS the prospects of wide use of a combination of acetylsalicylic acid and a rivaroxsaban of 2.5 mg 2 times a day in the patients with chronic coronary heart disease and/or symptom peripheral atherosclerosis are designated.

Nationwide trends in drug-coated balloon and drug-eluting stent utilization in the femoropopliteal arteries

OBJECTIVE

Drug-coated balloons (DCB) and drug-eluting stents (DES) have significantly altered treatment paradigms for femoropopliteal lesions. We aimed to describe changes in practice patterns as a result of the infusion of these technologies into the treatment of peripheral arterial disease.

METHODS

We queried the Vascular Quality Initiative registry from 2010 to 2017 for all peripheral vascular interventions involving the superficial femoral artery and/or the popliteal artery. Cases were divided into a PRE and a POST era with a cutoff of September 2016, when specific device identity was first recorded in Vascular Quality Initiative. For each artery, a primary treatment was identified as either plain balloon angioplasty, atherectomy, DCB, bare-metal stent, or DES. The relative distribution of primary treatments between the PRE and POST eras was evaluated, as were lesion characteristics associated with DCB and DES use and regional variability in the adoption of these new technologies.

RESULTS

Of 210,666 arteries in the dataset, 91,864 femoropopliteal arteries (across 74,842 procedures in 55,437 patients) were included. Each artery received 1.5 ± 0.6 treatments. Primary treatment use changed from 40% balloon angioplasty, 45% stenting, and 15% atherectomy in the PRE era to 22% plain balloon angioplasty, 26% bare-metal stent, 8% atherectomy, 37% DCB, and 8% DES in the POST era (P < .001). Forty-three percent of arteries received a drug-containing device as a primary or adjunctive therapy and 1.3% received both a DCB and DES in the POST era. DCB use as the primary treatment was highest in lesions with length 10.0 to 19.9 cm (42%), TransAtlantic InterSociety A, B, or C lesions (38%), and lesions with mild to no calcification (38%). DES use was highest in lesions with a length of 20 cm or more (12%), TransAtlantic InterSociety D lesions (13%), and lesions with moderate to severe calcification (9%). The range of use across 18 regions was 125 to 40% for DCB and 1% to 14% for DES. Regional variability was greater for DES (SD 4% vs mean 8%) than for DCB (SD 7% vs mean 29%).

CONCLUSIONS

There has been a rapid dissemination of DCB and DES technology in the femoropopliteal vessels, with nearly one-half of arteries receiving a drug-containing therapy in modern practice. DCBs are most used in medium length, minimally calcified lesions and DESs are most used in longer, more heavily calcified lesions. There is significant regional variability in adoption, especially with DES.

Sirtuin 3 Therapy Attenuates Aging Expression, Oxidative Stress Parameters, and Neointimal Hyperplasia Formation in Vein Grafts

BACKGROUND

Vein graft (VG) failure due to neointimal hyperplasia remains an important and unresolved problem in cardiovascular surgery. Sirtuin3 (SIRT3) is associated with oxidative stress and lifespan. We aimed to measure SIRT3 expression in the veins of humans and rats during aging, explore the inhibitory effects of SIRT3 on vascular smooth muscle cell (VSMC) proliferation and neointimal hyperplasia in VGs, and investigate the underlying mechanisms.

METHODS

SIRT3 mRNA and protein levels in saphenous veins of young and older humans and in veins of young and old rats were measured by quantitative real-time polymerized chain reaction (PCR) and Western blot analysis. Young and old male rats were randomized to the control (control), graft (graft), adenovirus-encoding green fluorescent protein (Ad-GFP), and adenovirus encoding SIRT3 (Ad-SIRT3) groups. At 7 days after operation, the mRNA and protein levels of SIRT3 and endothelial nitric oxide synthase (eNOS) were measured by quantitative real-time PCR and Western blot analysis. The mRNA levels and enzyme activity of manganese superoxide dismutase (MnSOD) and catalase (CAT) were measured by quantitative real-time PCR and enzymatic activity assay kits, and total nitric oxide (NO) levels were measured by biochemical assay kits. Histomorphometric analysis of VGs and immunohistochemical staining for proliferative activity were performed at 4 weeks after operation. The hemodynamic parameters of the VGs were also measured by ultrasonic examination.

RESULTS

SIRT3 mRNA and protein levels were lower in older human and rat veins than in younger human and rat veins. Ad-SIRT3 treatment significantly increased the expression and concentration of SIRT3, MnSOD, CAT, eNOS, and NO in VGs at 7 days after operation. Ad-SIRT3 gene transfer reduced the neointimal thickness and neointimal area/media area ratio in the VGs of the Ad-SIRT3 groups compared with the graft and Ad-GFP groups, especially in old rats. Proliferative activity was lower in the Ad-SIRT3 groups than in the other groups. The hemodynamic parameters of VGs were obviously improved in the Ad-SIRT3 groups.

CONCLUSIONS

SIRT3 expression decreases in the veins of humans and rats during aging. Furthermore, SIRT3 overexpression can significantly reduce VSMC proliferation and neointimal hyperplasia in VGs. Local intravenous delivery of adenovirus encoding SIRT3 may be a promising gene therapy for preventing VG failure.

Clinical validation of smartphone-based activity tracking in peripheral artery disease patients

Peripheral artery disease (PAD) is a vascular disease that leads to reduced blood flow to the limbs, often causing claudication symptoms that impair patients’ ability to walk. The distance walked during a 6-min walk test (6MWT) correlates well with patient claudication symptoms, so we developed the VascTrac iPhone app as a platform for monitoring PAD using a digital 6MWT. In this study, we evaluate the accuracy of the built-in iPhone distance and step-counting algorithms during 6MWTs. One hundred and fourteen (114) participants with PAD performed a supervised 6MWT using the VascTrac app while simultaneously wearing an ActiGraph GT9X Activity Monitor. Steps and distance-walked during the 6MWT were manually measured and used to assess the bias in the iPhone CMPedometer algorithms. The iPhone CMPedometer step algorithm underestimated steps with a bias of −7.2% ± 13.8% (mean ± SD) and had a mean percent difference with the Actigraph (Actigraph-iPhone) of 5.7% ± 20.5%. The iPhone CMPedometer distance algorithm overestimated distance with a bias of 43% ± 42% due to overestimation in stride length. Our correction factor improved distance estimation to 8% ± 32%. The Ankle-Brachial Index (ABI) correlated poorly with steps (R = 0.365) and distance (R = 0.413). Thus, in PAD patients, the iPhone’s built-in distance algorithm is unable to accurately measure distance, suggesting that custom algorithms are necessary for using iPhones as a platform for monitoring distance walked in PAD patients. Although the iPhone accurately measured steps, more research is necessary to establish step counting as a clinically meaningful metric for PAD.

Endovascular treatment of femoro-popliteal lesions

Peripheral artery disease (PAD) is a major health concern affecting more than 200 million people worldwide and studies have shown PAD to be a strong predictor of mortality, morbidity, and disability. The management of PAD is multi-tiered and advancements in technology have given physicians more options for endovascular revascularization if medical therapy does not result in substantial improvement. Many randomized controlled trials have reported efficacy of various therapies including laser atherectomy, stent technology, and drug-coated balloons over standard percutaneous transluminal angioplasty; however, uncertainty regarding the best standard of care remains unclear because of a lack of head to head comparisons between novel therapies. Furthermore, variability in the reported clinical outcomes exists and makes it difficult to evaluate the superiority of any specific treatment modality, especially for functional capacity and quality of life. Recently established consensus definitions for clinical outcomes coupled with investigators incorporating direct comparisons within clinical trials will be crucial to establish consistent care and meaningful gain in treatment for these patients. This review will highlight the treatment modalities, literature supporting each treatment modality, and insight into why they are being used and why variation exists around the United States.