A systematic review of treatment of intermittent claudication in the lower extremities

Rivaroxaban for Patients with Intermittent Claudication

BACKGROUND

The combination of rivaroxaban plus aspirin compared with aspirin alone reduces the risk of major adverse cardiovascular and limb events for high-risk patients with peripheral artery disease. It is unknown whether rivaroxaban plus aspirin improves intermittent claudication for adults with lower-risk peripheral arterial disease.

METHODS

In this randomized, open-label, multicenter, 24-week clinical trial, we randomly assigned patients with peripheral artery disease and intermittent claudication to receive either 2.5 mg of rivaroxaban twice daily plus 100 mg of aspirin once daily or 100 mg of aspirin once daily. The primary outcome was a 24-week change in total walking distance, measured by the 6-minute walking test. The primary safety outcome was the incidence of major bleeding or clinically relevant nonmajor bleeding.

RESULTS

Eighty-eight patients were randomly assigned to either rivaroxaban plus aspirin (n=46) or aspirin alone (n=42). The mean age was 67 years, and 54% were female. The total walking distance measured by 6-minute walk test improved by 89 ± 18 m (mean±standard error) in the rivaroxaban-plus-aspirin group versus 21 ± 16 m in the aspirin-alone group. This corresponded to an absolute difference of 68 ± 24 m (95% confidence interval [CI], 19 to 116 m; P=0.007) and a relative improvement over the aspirin-alone group of 327% (95% CI, 94 to 560%). No major bleeding events were observed in either group.

CONCLUSIONS

In patients with peripheral artery disease and intermittent claudication, 2.5 mg of rivaroxaban twice daily plus 100 mg of aspirin daily improved the total walking distance by a 6-minute walking test compared with 100 mg of aspirin daily alone. (Funded by Bayer S.A.; Clinicaltrials.gov number, NCT04853719.).

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia).

METHODS

A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate.

STRUCTURE

Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia).

METHODS

A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate.

STRUCTURE

Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

Clinical impact of fluoropolymer-based drug-eluting stent thrombosis in femoropopliteal artery occlusive lesions

BACKGROUND

Endovascular treatment (EVT) is recommended for superficial femoral artery (SFA) lesions, and good results have been reported after implantation of drug-eluting stents (DES) for SFA. However, the major concern after implantation is acute thrombosis during the follow-up period, resulting in major amputation and major adverse limb events. In this study, we examined the incidence and outcome of acute thrombosis after DES implantation in the SFA.

OBJECTIVES AND METHODS

DES implantation for a femoropopliteal lesion was performed in 288 patients at multiple centers in Japan from 2019 to 2021. A total of 25 patients (8.6%) with DES acute occlusion were analyzed retrospectively. The primary endpoint was amputation-free survival (AFS) after acute occlusion.

RESULTS

The median patient age was 77 years, with 48% having diabetes, 40% undergoing maintenance dialysis, and 66% having chronic limb-threatening ischemia (CLTI). The mean time from initial DES implantation to acute occlusion was 153.5 ± 177.6 days, with a median of 104 days. EVT was performed in 18 patients (72%), surgical revascularization in 3 (12%), and conservative treatment in 4 (16%). Two deaths within 30 days were both due to sepsis. No major amputation or major adverse cardiovascular events occurred within 30 days. The 1-year rates of patency and freedom from target lesion revascularization after DES thrombosis were 22.9% and 48.8%, respectively. AFS at 1 year was 55.1%.

CONCLUSION

Acute DES occlusion is relatively frequent, and the outcome is poor. Therefore, the indication of DES implantation for a complex SFA lesion may require careful consideration. Further investigation may be needed in DES implantation for a complex SFA lesion.

Outcomes of Omniflow® II prosthesis used for revascularization in the femoral tract both in infected and non-infected setting

BACKGROUND

Evidence regarding the outcomes of Omniflow® II prosthesis in peripheral arterial revascularization at different anatomical sites and for different indications is scarce. Therefore, the aim of this study was to evaluate the outcomes of the Omniflow® II used at various positions within the femoral tract both in infected and non-infected setting.

METHODS

Patients who underwent reconstructive lower leg vascular surgery with implantation of an Omniflow® II from 2014 until 2021 at five medical centers were retrospectively included (N.=142). Patients were subdivided into the following categories: femoro-femoral crossover (N.=19), femoral interposition (N.=18), femoro-popliteal (above-the-knee [N.=25; AK] or below-the-knee [N.=47; BK]), and femoro-crural bypass grafts (N.=33). Primary outcome was primary patency and secondary outcomes included primary assisted patency, secondary patency, major amputation, vascular graft infection, and mortality. Outcomes were compared according to different subgroups and the surgical setting (infected versus non-infected).

RESULTS

The median follow-up was 35.0 (17.5-54.3) months. Three years primary patency of 58% was observed for femoro-femoral crossover bypass, 75% for femoral interposition graft, 44% for femoro-popliteal above-the-knee bypass, 42% for femoro-popliteal below-the-knee bypass, and 27% in the femoro-crural position (P=0.006). Freedom from major amputation at three years were 84% for femoro-femoral crossover bypass, 88% for femoral interposition bypass, 90% for femoro-popliteal AK bypass, 83% for femoro-popliteal BK bypass, and 50% for femoro-crural bypass (P<0.001).

CONCLUSIONS

This study demonstrates the safety and feasibility of the use of Omniflow® II for femoro-femoral crossover-, femoral interposition-, and femoro-popliteal (AK and BK) bypass. Omniflow® II seems to be less suitable for femoro-crural bypass with a significantly lower patency compared to other positions.

Expression level and clinical significance of LncRNA PVT1 in the serum of patients with LEASO

Objective

Our study aims to investigate the long non-coding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) in lower extremity arteriosclerosis obliterans (LEASO) patient serum and its clinical significance in LEASO.

Patients and Methods

From July 2021 to April 2022, 133 LEASO patients diagnosed at the Qingdao Municipal Hospital were included. Among them, 44 complicated with coronary artery disease (CAD) were classified as the LEASO with CAD group. The remaining 89 were marked as the LEASO group, which was classified into single (n = 48) and double (n = 41) lower limb groups, with the former being subclassified into the left (n = 28) and right (n = 20) lower limb groups based on the affected sites. Fifty healthy individuals who came to our hospital for physical examination during the same period were randomly included and defined as the Healthy Control group. PVT1 expression was detected in serum samples from each group using a quantitative reverse transcriptase-polymerase chain reaction , and differences in expression levels were calculated. The ankle-brachial index (ABI) of patients in the LEASO group was measured using a sphygmomanometer, and its correlation with PVT1 was analyzed. Clinical data and laboratory test results (including blood routine, liver and renal function, and blood lipids) were collected for all patients upon admission. Logistic regression analyses were performed to determine the influence of PVT1 and laboratory test results on LEASO. The diagnosis and prediction of LEASO were obtained by combing PVT1 with laboratory test indicators.

Results

It was found that lncRNA PVT1 expression was the highest in the serum of the LEASO with CAD group, followed by the LEASO and control groups (P < 0.05). Within the LEASO group, no significant difference in PVT1 expression was seen between the left and right limbs (P > 0.05), nor between the single and double lower limb groups. Furthermore, the PVT1 expression increased with the Rutherford grades, indicating a negative correlation between PVT1 and ABI. Logistic regression analysis revealed that triglycerides (OR = 2.972, 95% CI [1.159-7.618]), cholesterol (OR = 6.655, 95% CI [1.490-29.723]), C-reactive protein (OR = 1.686, 95% CI [1.218-2.335]), and PVT1 (OR = 2.885, 95% CI [1.350-6.167]) were independent risk factors for LEASO. Finally, strong sensitivity was observed in the receiver operating characteristic curve when combining PVT1 with meaningful laboratory indicators to diagnose and predict LEASO.

Conclusion

lncRNA PVT1 promotes LEASO occurrence and progression and is related to atherosclerosis severity. The expression of PVT1 was negatively correlated with ABI. Logistic regression analysis suggested that blood lipid levels and inflammatory reactions might be related to LEASO occurrence. PVT1 was incorporated into laboratory indicators to predict LEASO. The subject's working curve area was large, and the prediction results were highly sensitive.

iMPI: portable human-sized magnetic particle imaging scanner for real-time endovascular interventions

Minimally invasive endovascular interventions have become an important tool for the treatment of cardiovascular diseases such as ischemic heart disease, peripheral artery disease, and stroke. X-ray fluoroscopy and digital subtraction angiography are used to precisely guide these procedures, but they are associated with radiation exposure for patients and clinical staff. Magnetic Particle Imaging (MPI) is an emerging imaging technology using time-varying magnetic fields combined with magnetic nanoparticle tracers for fast and highly sensitive imaging. In recent years, basic experiments have shown that MPI has great potential for cardiovascular applications. However, commercially available MPI scanners were too large and expensive and had a small field of view (FOV) designed for rodents, which limited further translational research. The first human-sized MPI scanner designed specifically for brain imaging showed promising results but had limitations in gradient strength, acquisition time and portability. Here, we present a portable interventional MPI (iMPI) system dedicated for real-time endovascular interventions free of ionizing radiation. It uses a novel field generator approach with a very large FOV and an application-oriented open design enabling hybrid approaches with conventional X-ray-based angiography. The feasibility of a real-time iMPI-guided percutaneous transluminal angioplasty (PTA) is shown in a realistic dynamic human-sized leg model.

Clonal Hematopoiesis Mutations Are Present in Atherosclerotic Lesions in Peripheral Artery Disease

Clonal hematopoiesis (CH)-associated mutations increase the risk of atherosclerotic cardiovascular diseases. However, it is unclear whether the mutations detected in circulating blood cells can also be detected in tissues associated with atherosclerosis, where they could affect physiology locally. To address this, the presence of CH mutations in peripheral blood, atherosclerotic lesions and associated tissues was assessed in a pilot study of 31 consecutive patients with peripheral vascular disease (PAD) who underwent open surgical procedures. Next-generation sequencing was used to screen the most commonly mutated loci (DNMT3A, TET2, ASXL1 and JAK2). Twenty CH mutations were detected in peripheral blood of 14 (45%) patients, 5 of whom had more than one mutation. TET2 (11 mutations, 55%) and DNMT3A (8 mutations, 40%) were the most frequently affected genes. Altogether, 88% of the mutations detectable in peripheral blood were also present in the atherosclerotic lesions. Twelve patients also had mutations in perivascular fat or subcutaneous tissue. The presence of CH mutations in PAD-associated tissues as well as in blood suggests that CH mutations may make a previously unknown contribution to PAD disease biology.

Differential expression pattern, bioinformatics analysis, and validation of circRNA and mRNA in patients with arteriosclerosis

Background

Lower limb arteriosclerosis obliterans (ASO) is the formation of atherosclerotic plaques in lower limb arteries, leading to vascular stenosis and occlusion, and is a major factor leading to lower limb amputation. The ASO seriously endangers the physical and mental health of patients. As living standards improve, the disease tends to occur in younger patients, and the incidence keeps increasing year by year. The circular RNAs (circRNAs) have been found to be tissue-specific, and they play an important role in a variety of diseases, but there are few studies on the pathogenic role and expression of circRNAs in ASOs.

Method

Three diseased arteries from patients with ASO and three healthy arteries from healthy donors were collected for second-generation sequencing, and the pathogenic pathways and possible pathogenic circRNAs related to ASO were screened through bioinformatics analysis. PCR and agarose gel electrophoresis were used to validate the sequencing results. The expression of circRNA-0008706 in human arterial smooth muscle cells (HASMCs) was knocked down using siRNA technology to explore its function.

Result

We identified 480 differentially expressed (DE) circRNAs and 2,997 DEmRNAs. Functional analysis revealed that epithelial-to-mesenchymal transition (EMT), lipid transport, regulation of extracellular matrix disassembly, regulation of cardiac muscle cell proliferation, branched-chain amino acid biosynthetic process, and positive regulation of cell growth and migration were enriched. Based on our previous microRNA array results, we constructed an ASO disease-specific competing endogenous (ceRNA) network. After validation, circRNA-0008706 was selected for functional analysis. Knockdown of circRNA-0008706 significantly suppressed the proliferation and migration phenotype of HASMCs and decreased the BCAT1 expression, which may be due to the specific binding of circRNA-0008706 to microRNA-125b-5p.

Conclusion

This study is the first to compare the circRNA and mRNA expression profiles of ASOs and healthy arterial specimens and to construct a disease-specific ceRNA network for ASOs. This study may provide a new therapeutic target for ASO.

A Description of Outcomes Experienced by Patients Whose Orders for Peripheral Artery Revascularization Were Reviewed by a Nondenial Prior Authorization Program

Objective

After a nondenial prior authorization program evaluates orders for peripheral artery revascularization (PAR), ordering physicians sometimes withdraw their orders based upon program recommendations. Some patients with withdrawn orders receive PAR if claudication does not resolve. To characterize patient outcomes under this program, we evaluated whether associations existed between the withdrawal of patients’ initial PAR orders and the presence of claims for PAR and claims mentioning intermittent claudication (IC) in the following 16 weeks.

Methods

Orders for PAR placed from 1/1/19 to 9/30/19 for patients with Medicare Advantage health plans were extracted from a national healthcare organization’s database. Claims data from 0 to 16 weeks following the order were reviewed to determine if patients had downstream PAR claims, or if they had emergency department or hospital claims mentioning IC. Chi-square tests were used to assess the association between order withdrawal and downstream PAR, as well as claims mentioning IC. Multivariate logistic regressions were run to assess the same, controlling for patient age, sex, urbanicity, local median income, state obesity rate, type of PAR, ordering physician specialty, and whether PAR was ordered in a hospital setting.

Results

Of 1588 orders meeting inclusion criteria, 71.9% (1038/1444) of authorized orders and 61.1% (88/144) of withdrawn orders were followed by PAR within 16 weeks, a significant difference ( P < .01). Relatedly, 69.8% (1008/1444) of authorized orders and 70.8% (102/144) of withdrawn orders were followed by IC claims, an insignificant difference. Multivariate logistic regressions showed patients with withdrawn PAR orders had significantly lower adjusted odds of PAR (OR: 0.63; 95% CI: 0.44–0.91), but an insignificant difference in their adjusted odds of IC (OR: 1.10; CI: 0.76–1.64).

Conclusions

Although patients with withdrawn PAR orders were significantly less likely to receive PAR in the subsequent 16 weeks, no association was found between withdrawn PAR orders and subsequent claims mentioning IC.

Rivaroxaban with Aspirin Versus Aspirin for Peripheral Arterial Disease and Intermittent Claudication. Rationale and Design of the COMPASS CLAUDICATION Trial

BACKGROUND

The COMPASS trial demonstrated that in patients with peripheral arterial disease, the combination of rivaroxaban and aspirin compared with aspirin reduces the risk of major adverse limb events, but it is not known whether this combination can also improve symptoms in patients with intermittent claudication. The primary objective of this study is to evaluate the effect of the combination on claudication distance.

STUDY DESIGN

Eighty-eight patients with intermittent claudication will be randomized to receive rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily or aspirin 100 mg once daily for 24 weeks. The primary outcome is the change in claudication distance from the baseline to 24 weeks, measured by 6 min walking test and treadmill test. The primary safety outcome is the incidence of major bleeding and clinically relevant non-major bleeding according to the International Society on Thrombosis and Hemostasis criteria.

SUMMARY

The COMPASS CLAUDICATION trial will provide high-quality evidence regarding the effect of the combination of rivaroxaban and aspirin on claudication distance in patients with peripheral arterial disease.

Influence of Peripheral Transluminal Angioplasty Alongside Exercise Training on Oxidative Stress and Inflammation in Patients with Peripheral Arterial Disease

In patients with intermittent claudication, exercise training ameliorates inflammation by reducing oxidative stress. A total of 41 patients with intermittent claudication (Rutherford 3) were included in the study (with 21 patients treated by endovascular revascularization (ER), and 20 patients without ER). All patients were referred to home-based exercise training. Absolute and initial claudication distance (ACD, ICD) and ABI (ankle–brachial index) were measured. ROS (reactive oxygen species) formation was measured using the luminol analogue L-012. Follow-up was performed after 3 months. ROS production after NOX2 (NAPDH oxidase 2) stimulation showed a significant reduction in both groups at follow-up (PTA group: p = 0.002, control group: p = 0.019), with a higher relative reduction in ROS in the PTA group than in the control group (p = 0.014). ABI measurements showed a significant increase in the PTA (peripheral transluminal angioplasty) group (p = 0.001), but not in the control group (p = 0.127). Comparing both groups at follow-up, ABI was higher in the PTA group (p = 0.047). Both groups showed a significant increas ACD and ICD at follow-up (PTA group: ACD: p = 0.001, ICD: p < 0.0001; control group: ACD: p = 0.041, ICD: p = 0.002). There was no significant difference between both groups at follow-up (ACD: p = 0.421, ICD: p = 0.839). Endovascular therapy in combination with exercise training leads to a lower leukocyte activation state with a reduced NOX2-derived ROS production paralleled by an improved ABI, ACD and ICD. Our data support the strategy to combine exercise training with preceding endovascular therapy.

Lower extremity arterial interventions in England

INTRODUCTION

The increasing prevalence of diabetes mellitus and advances in endovascular therapies continue to have an impact on the epidemiology and management of lower extremity arterial disease. This study describes trends in lower extremity revascularisation and major lower limb amputation in NHS England over the past two decades (2000-2019).

METHODS

Numbers of lower extremity endovascular interventions, open surgical procedures and major lower limb amputations performed in NHS England between 2000 and 2019 were extracted from publicly available hospital admitted patient care activity reports. Trends in intervention were assessed with linear regression models and chi-square tests for trend.

RESULTS

Over this period, 527,131 revascularisations and 92,053 amputations were performed. The mean age of patients was 67.5 years (standard deviation 1.6 years) and 65.3% were male. The number of lower limb revascularisation procedures increased by 402.4 units/year (95% confidence interval, CI, 290.1-514.6, p < 0.001). The number of endovascular interventions rose by 43.5% (10,912 in 2000 vs 15,657 in 2019; β = 359.5.0, 95% CI 279.3-439.8, p < 0.001) compared with no significant increase in the number of open surgical procedures (8,483 in 2000 vs 7,872 in 2019; β = 42.8, 95% CI -8.3 to 94.0, p = 0.095). The number of major lower limb amputations has decreased by 9.4% (5,418 in 2000 vs 4,907 in 2019; β = -31.0; 95% CI -49.6 to -12.5, R² = 0.42, p = 0.003).

CONCLUSIONS

There has been a significant increase in the rate of lower limb revascularisation procedures associated with decreased numbers of major lower limb amputations over the past two decades. These changes in overall trends may affect both service provision and vascular surgery training planning.

Three-Year Outcomes From the LIBERTY 360 Study of Endovascular Interventions for Peripheral Artery Disease Stratified by Rutherford Category

Purpose:

To report the 3-year results of the LIBERTY 360 study, which investigated outcomes of endovascular treatment of symptomatic peripheral artery disease (PAD).

Materials and Methods:

The LIBERTY trial ( ClinicalTrials.gov identifier NCT01855412) was a prospective, observational, core laboratory–assessed, multicenter study of endovascular interventions enrolling >1200 participants treated at 51 sites. Data from 1189 patients were stratified according to Rutherford category (RC) and analyzed [RC 2-3 (n=500), RC 4-5 (n=589), and RC 6 (n=100)]. The primary outcomes were major amputation of the target limb and all-cause death; secondary outcomes were target vessel revascularization (TVR) or target lesion revascularization (TLR); major adverse events (MAEs; death within 30 days, TVR or TLR, and major amputation); death or major amputation combined; and change in self-reported quality of life (QoL) measures (VascuQol-25). The Kaplan-Meier (KM) method was employed to estimate the outcomes; estimates are presented with the 95% confidence intervals (CI). Predictors of 3-year MAE, death, TVR, and major amputation were analyzed using Cox proportional hazard regression modeling.

Results:

The 36-month KM survival rates were 86.0% in RC 2-3, 79.8% in RC 4-5, and 62.0% in RC 6 groups. The KM estimates of freedom from major amputation at 36 months were 98.5% in RC 2-3, 94.0% in RC 4-5, and 79.9% in RC 6. The 36-month KM estimates for freedom from TVR/TLR were 71.1% in RC 2-3, 64.2% in RC 4-5 and 61.9% in RC 6 groups. Patients with claudication at baseline were at lower risk for MAEs compared with RC 4-5 and RC 6 patients during the 36-month follow-up. Vascular QoL improved from baseline and persisted up to 36 months in all patients.

Conclusion:

Endovascular therapy is a viable treatment option for patients with symptomatic PAD, with sustained improved quality of life in both claudicants and patients with chronic limb-threatening ischemia. These results provide important point estimates for midterm outcomes after modern endovascular interventions for PAD.

Quantifying the risk-adjusted hospital costs of postoperative complications after lower extremity bypass in patients with claudication

OBJECTIVE

Increasing evidence has shown that the risks associated with surgical revascularization for intermittent claudication outweigh the benefits. The aim of our study was to quantify the cost of care associated with perioperative complications after elective lower extremity bypass (LEB) in patients presenting with intermittent claudication.

METHODS

All patients undergoing first-time LEB for claudication in the Healthcare Database (2009-2015) were included. The primary outcome was in-hospital postoperative complications, including major adverse limb events (MALE), major adverse cardiac events (MACE), acute kidney injury, and wound complications. The overall crude hospital costs are reported, and a generalized linear model with log link and inverse Gaussian distribution was used to calculate the predicted hospital costs for specific complications.

RESULTS

Overall, 7154 patients had undergone elective LEB for claudication during the study period. The median age was 66 years (interquartile range, 59-73 years), 67.5% were male, and 75.3% were white. Two thirds of patients (61.2%) had Medicare insurance, followed by private insurance (26.9%), Medicaid (7.7%), and other insurance (4.2%). In-hospital complications occurred in 8.5% of patients, including acute kidney injury in 3.0%, MALE in 2.8%, wound complications in 2.3%, and MACE in 1.0%. The overall median crude hospital cost was $11,783 (interquartile range, $8911-$15,767) per patient. The incremental increase in cost associated with a postoperative complication was significant, ranging from $6183 (95% confidence interval, $4604-$7762) for MALE to $10,485 (95% confidence interval, $6529-$14,441) for MACE after risk adjustment.

CONCLUSIONS

Postoperative complications after elective LEB for claudication are not uncommon and increase the in-hospital costs by 46% to 78% depending on the complication. Surgical revascularization for claudication should be used sparingly in carefully selected patients.

Rehabilitation progress after lower-extremity bypass surgery in patients with peripheral arterial disease with different occlusive lesions

[Purpose] To examine the differences in rehabilitation progress after lower-extremity bypass surgery for peripheral arterial disease (PAD) depending on the occlusive lesions. [Participants and Methods] This was a retrospective study. We included 50 patients (61 limbs; 38 males and 12 females; mean age, 73 years) who underwent lower-extremity bypass surgery for Fontaine stage 2–3 PAD. The patients were assigned to the aortoiliac (A-I) group (n=23), femoropopliteal (F-P) group (n=18), and below-knee group (n=9). We evaluated the postoperative rehabilitation progress and length of hospital stay of these groups. [Results] The postoperative ankle-brachial pressure index (ABI) of the A-I group was significantly lower than that of the F-P group, although there were no differences before surgery. The progress of rehabilitation and the length of hospitalization showed no significant differences among the three groups. The postoperative date of independent walking was significantly later in the presence of complications than in the absence of complications. [Conclusion] The progress of rehabilitation after lower-extremity bypass surgery did not differ depending on the occlusive lesions, and patients may acquire independent walking ability in approximately 5 days in the absence of postoperative complications.

Microvascular Dysfunction in Peripheral Artery Disease: Is Heat Therapy a Viable Treatment?

Peripheral artery disease (PAD) is characterized by the development of atherosclerotic plaques in the lower-body conduit arteries. PAD is commonly accompanied by microvascular disease, which may result in poor wound healing, plantar ulcer development, and subsequent limb amputation. Understanding the mechanisms underlying the development of plantar ulcers is a critical step in the development of adequate treatment options for patients with PAD. Skin is classified into two major components: glabrous and non-glabrous. These skin types have unique microcirculation characteristics, making it important to differentiate between the two when investigating mechanisms for plantar ulcer development in PAD. There is evidence for a microcirculation compensatory mechanism in PAD. This is evident by the maintenance of basal microcirculation perfusion and capillary filling pressure despite a reduced pressure differential beyond an occlusion in non-critical limb ischemia PAD. The major mechanism for this compensatory system seems to be progressive vasodilation of the arterial network below an occlusion. Recently, heat therapies have emerged as novel treatment options for attenuating the progression of PAD. Heat therapies are capable of stimulating the cardiovascular system, which may lead to beneficial adaptations that may ultimately reduce fatigue during walking in PAD. Early work in this area has shown that full-body heating is capable of generating an acute cardiovascular response, similar to exercise, which has been suggested as the most efficient treatment modality and may generate adaptations with chronic exposure. Heat therapies may emerge as a conservative treatment option capable of attenuating the progression of PAD and ultimately impeding the development of plantar ulcers.

Factors associated with long-term graft patency after lower extremity arterial bypasses

Purpose

This study was conducted to determine factors associated with long-term graft patency after lower extremity arterial bypass (LEAB).

Methods

Database of LEABs for patients with chronic arterial occlusive disease (CAOD) at a single institution was retrospectively reviewed. To determine the factors we compared demographic, clinical, and procedural variables between 2 patient groups; group I (graft patency < 2 years) and group II (graft patency ≥ 5 years after LEAB) using univariable and multivariable analyses.

Results

Among 957 LEABs, 259 limbs (group I, 125 limbs and group II, 134 limbs) in 213 patients were included for the analysis. On a univariable analysis, younger age (69 years vs. 66 years, P = 0.024), hypertension (60.8% vs. 74.6%, P = 0.017), claudication (51.2% vs. 70.9%, P = 0.001), absence of prior intervention (50.4% vs. 73.9%, P < 0.001), common femoral artery based bypass (57.6% vs. 70.1%, P = 0.035), above-the knee bypass (36.8% vs. 64.2%, P < 0.001), postoperative graft salvage procedure (3.2% vs. 14.8%, P = 0.001), and statin use (75.2% vs. 88.8, P = 0.004) were associated with long-term patency. On a multivariate analysis hypertension (odds ratio [OR], 1.91; P = 0.038), claudication (OR, 2.08; P = 0.032), no prior intervention (OR, 2.48; P = 0.001), vein graft (OR, 4.36; P = 0.001), above-the knee bypass (OR, 4.68; P < 0.001), and graft salvage procedures (OR, 7.70; P < 0.001) were identified as independent factors.

Conclusion

These factors can be considered in decision making before treatment of patients with CAOD.

MicroRNA-130a inhibits proliferation of vascular smooth muscle cells by suppressing autophagy via ATG2B

Numerous microRNAs participate in regulating the pathological process of atherosclerosis. We have found miR-130a is one of the most significantly down-regulated microRNAs in arteriosclerosis obliterans. Our research explored the function of miR-130a in regulating proliferation by controlling autophagy in arteriosclerosis obliterans development. A Gene Ontology (GO) enrichment analysis of miR-130a target genes indicated a correlation between miR-130a and cell proliferation. Thus, cell cycle, CCK-8 assays and Western blot analysis were performed, and the results indicated that miR-130a overexpression in vascular smooth muscle cells (VSMCs) significantly attenuated cell proliferation, which was validated by an in vivo assay in a rat model. Moreover, autophagy is thought to be involved in the regulation of proliferation. As our results indicated, miR-130a could inhibit autophagy, and ATG2B was predicted to be a target of miR-130a. The autophagy inhibition effect of miR-130a overexpression was consistent with the effect of ATG2B knockdown. The results that ATG2B plasmids and miR-130a mimics were cotransfected in VSMCs further confirmed our conclusion. In addition, by using immunohistochemistry, the positive results of LC3 II/I and ATG2B in the rat model and artery vascular tissues from the patient were in accordance with in vitro data. In conclusion, our data demonstrate that miR-130a inhibits VSMCs proliferation via ATG2B, which indicates that miR-130a could be a potential therapeutic target that regulates autophagy in atherosclerosis obliterans.

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.

Two-Year Efficacy and Safety Results from the IMPERIAL Randomized Study of the Eluvia Polymer-Coated Drug-Eluting Stent and the Zilver PTX Polymer-free Drug-Coated Stent

PURPOSE

To report additional endpoints, including 2-year primary patency, patient outcomes, and safety results, as well as the initial assessment of hypoechogenic halo from the IMPERIAL Randomized Controlled Trial (RCT).

MATERIALS AND METHODS

IMPERIAL RCT is a prospective, randomized (2:1), multicenter study of patients with symptomatic femoropopliteal artery lesions (length 30-140 mm, Rutherford category 2-4) treated with the Eluvia paclitaxel-eluting nitinol stent or the Zilver PTX paclitaxel-coated stent. Two-year follow-up included patency, safety, and mortality assessments and core laboratory-reviewed B-mode ultrasound imaging to screen for hypoechogenic halo in the stented segment, and assess blood flow.

RESULTS

At 24 months, all-cause mortality was 7.1% (21/295) for Eluvia and 8.3% (12/145) for Zilver PTX (P = 0.6649). The clinically driven target lesion revascularization rate was significantly less for patients treated with Eluvia vs Zilver PTX (12.7% vs 20.1%; P = 0.0495). The Kaplan-Meier estimate of primary patency at 24 months was 83.0% for Eluvia and 77.1% for Zilver PTX (log rank P = 0.1008). Transverse ultrasound imaging was implemented during the 24-month follow-up window and was evaluable for 27.5% (128/465) of patients. Hypoechogenic halo prevalence rates did not differ significantly between Eluvia and Zilver PTX study arms (33.7% [29/86] vs 21.4% [9/42]; P = 0.153). In no case was flow documented within the halo; no adverse events were associated with these ultrasound findings.

CONCLUSION

Two-year follow-up suggests a sustained advantage for Eluvia for avoiding target lesion revascularization. Initial hypoechogenic halo assessment showed no difference in prevalence between the study arms, no flow within the halo, and no associated adverse events.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov identifier NCT02574481. Date of registration: October 14, 2015.

LEVEL OF EVIDENCE

Level 1; randomized controlled trial.

Asia-Pacific Consensus Statement on the Management of Peripheral Artery Disease: A Report from the Asian Pacific Society of Atherosclerosis and Vascular Disease Asia-Pacific Peripheral Artery Disease Consensus Statement Project Committee

BACKGROUND

Peripheral artery disease (PAD) is the most underdiagnosed, underestimated and undertreated of the atherosclerotic vascular diseases despite its poor prognosis. There may be racial or contextual differences in the Asia-Pacific region as to epidemiology, availability of diagnostic and therapeutic modalities, and even patient treatment response. The Asian Pacific Society of Atherosclerosis and Vascular Diseases (APSAVD) thus coordinated the development of an Asia-Pacific Consensus Statement (APCS) on the Management of PAD.

OBJECTIVES

The APSAVD aimed to accomplish the following: 1) determine the applicability of the 2016 AHA/ACC guidelines on the Management of Patients with Lower Extremity Peripheral Artery Disease to the Asia-Pacific region; 2) review Asia-Pacific literature; and 3) increase the awareness of PAD.

METHODOLOGY

A Steering Committee was organized to oversee development of the APCS, appoint a Technical Working Group (TWG) and Consensus Panel (CP). The TWG appraised the relevance of the 2016 AHA/ACC PAD Guideline and proposed recommendations which were reviewed by the CP using a modified Delphi technique.

RESULTS

A total of 91 recommendations were generated covering history and physical examination, diagnosis, and treatment of PAD-3 new recommendations, 31 adaptations and 57 adopted statements. This Asia-Pacific Consensus Statement on the Management of PAD constitutes the first for the Asia-Pacific Region. It is intended for use by health practitioners involved in preventing, diagnosing and treating patients with PAD and ultimately the patients and their families themselves.

Rationale and design of the granulocyte-macrophage colony stimulating factor in peripheral arterial disease (GPAD-3) study

BACKGROUND

Lower extremity peripheral arterial disease (PAD) is a public health problem and many patients with PAD experience claudication despite adequate medical and/or surgical management. Mobilization of endogenous progenitor cells using Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) is a novel therapeutic option that has shown promising results in experimental models and phase I/IIA clinical trials. The GPAD-3 trial will study the effect of two successive administrations of GM-CSF at 3-month interval for improving claudication among patients with lower extremity PAD.

METHODS

We plan to recruit 176 patients in this ongoing randomized, double-blind, placebo-controlled Phase IIB trial. After screening for inclusion and exclusion criteria, eligible subjects undergo a 4-week screening phase where they perform subcutaneous placebo injections thrice weekly and walk at least three times a day until they develop claudication. After the screening phase, eligible subjects undergo baseline testing and are randomized 2:1 to receive 500 μg/day of GM-CSF subcutaneously thrice weekly for three weeks or placebo injections. After 3 months, follow-up endpoint testing is performed and subjects in the GM-CSF group receive the second administration of the drug for three weeks while subjects in placebo group receive matching placebo injections. All participants undergo endpoint testing at six-month and nine-month follow-up. The primary endpoint is change in 6-min walk distance between baseline and 6-month follow-up.

CONCLUSION

GPAD-3 explores a novel approach to address the need for alternative therapies that can alleviate symptoms among patients with lower extremity PAD. If successful, this study will pave the way for a pivotal Phase III trial.

A Systematic Review of Economic Evaluations in Vascular Surgery

BACKGROUND

With increasing healthcare costs and the emergence of new technologies in vascular surgery, economic evaluations play a critical role in informing decision-making that optimizes patient outcomes while minimizing per capita costs. The objective of this systematic review is to describe all English published economic evaluations in vascular surgery and to identify any significant gaps in the literature.

METHODS

We conducted a comprehensive English literature review of EMBASE, MEDLINE, The Cochrane Library, Ovid Health Star, and Business Source Complete from inception until December 1, 2018. Two independent reviewers screened articles for eligibility using predetermined inclusion criteria and subsequently extracted data. Articles were included if they compared 2 or more vascular surgery interventions using either a partial economic evaluation (cost analysis) or full economic evaluation (cost-utility, cost-benefit, and/or cost-effectiveness analysis). Data extracted included publishing journal, date of publication, country of origin of authors, type of economic evaluation, and domain of vascular surgery.

RESULTS

A total of 234 papers were included in the analysis. The majority of the papers included only a cost analysis (183, 78%), and there were only 51 papers that conducted a full economic analysis (22%). The 51 papers conducted a total of 69 economic analyses. This consisted of 32 cost-effectiveness analyses, 29 cost-utility analyses, and 8 cost-benefit analyses. The most common domains studied were aneurysmal disease (89, 38%) and peripheral vascular disease (50, 21%). Economic evaluations were commonly published in the Journal of Vascular Surgery (83, 35%) and Annals of Vascular Surgery (32, 14%), with most study authors located in the United States (127, 54%). There was a trend of economic evaluations being published more frequently in recent years.

CONCLUSIONS

The majority of vascular surgery economic evaluations used only a cost analysis, rather than a full economic evaluation, which may not be ideal in pursuing interventions that simultaneously optimize cost and patient outcomes. The literature is lacking in full economic evaluations-a trend persistent in other surgical specialties-and there is a need for full economic evaluations to be conducted in the field of vascular surgery.

Development of a two-stage limb ischemia model to better simulate human peripheral artery disease

Peripheral arterial disease (PAD) develops due to the narrowing or blockage of arteries supplying blood to the lower limbs. Surgical and endovascular interventions are the main treatments for advanced PAD but alternative and adjunctive medical therapies are needed. Currently the main preclinical experimental model employed in PAD research is based on induction of acute hind limb ischemia (HLI) by a 1-stage procedure. Since there are concerns regarding the ability to translate findings from this animal model to patients, we aimed to develop a novel clinically relevant animal model of PAD. HLI was induced in male Apolipoprotein E (ApoE-/-) deficient mice by a 2-stage procedure of initial gradual femoral artery occlusion by ameroid constrictors for 14 days and subsequent excision of the femoral artery. This 2-stage HLI model was compared to the classical 1-stage HLI model and sham controls. Ischemia severity was assessed using Laser Doppler Perfusion Imaging (LDPI). Ambulatory ability was assessed using an open field test, a treadmill test and using established scoring scales. Molecular markers of angiogenesis and shear stress were assessed within gastrocnemius muscle tissue samples using quantitative polymerase chain reaction. HLI was more severe in mice receiving the 2-stage compared to the 1-stage ischemia induction procedure as assessed by LDPI (p = 0.014), and reflected in a higher ischemic score (p = 0.004) and lower average distance travelled on a treadmill test (p = 0.045). Mice undergoing the 2-stage HLI also had lower expression of angiogenesis markers (vascular endothelial growth factor, p = 0.004; vascular endothelial growth factor- receptor 2, p = 0.008) and shear stress response mechano-transducer transient receptor potential vanilloid 4 (p = 0.041) within gastrocnemius muscle samples, compared to animals having the 1-stage HLI procedure. Mice subjected to the 2-stage HLI receiving an exercise program showed significantly greater improvement in their ambulatory ability on a treadmill test than a sedentary control group. This study describes a novel model of HLI which leads to more severe and sustained ischemia than the conventionally used model. Exercise therapy, which has established efficacy in PAD patients, was also effective in this new model. This new model maybe useful in the evaluation of potential novel PAD therapies.

Cross-sectoral rehabilitation intervention for patients with intermittent claudication versus usual care for patients in non-operative management - the CIPIC Rehab Study: study protocol for a randomised controlled trial

INTRODUCTION

Intermittent claudication (IC) caused by peripheral artery disease (PAD) is a common cardiovascular disease. Patients with IC have reduced walking capacity, restricted activity levels and mobility, and reduced health-related quality of life. The disease leads to social isolation, the risk of cardiovascular morbidity, and mortality. Non-operative management of IC requires exercise therapy and studies show that supervised exercise training is more effective than unsupervised training, yet many patients with IC lack motivation for changes in health behaviour. No studies investigating the effects of existing cardiac rehabilitation targeted patients with IC have been published. The aim of this article is to present the rationale and design of the CIPIC Rehab Study, which examines the effect of a cross-sectoral rehabilitation programme versus usual care for patients in non-operative management for IC.

METHODS AND ANALYSIS

A randomised clinical trial aims to investigate whether cardiac rehabilitation for patients with IC in non-operative management versus usual care is superior to treatment as usual. The trial will allocate 118 patients, with a 1:1 individual randomisation to either the intervention or control group. The primary outcome is maximal walking distance measured by the standardised treadmill walking test. The secondary outcome is pain-free walking distance measured by the standardised treadmill walking test, healthy diet measured by a fat-fish-fruit-green score, and level of physical activity measured by an activity score within official recommendations. Statistical analyses will be blinded. Several exploratory analyses will be performed. A mixed-method design is used to evaluate qualitative and quantitative findings. A qualitative and a survey-based complementary study will be undertaken to investigate patients' post-discharge experiences. A qualitative post-intervention study will explore experiences of participation in rehabilitation.

DISCUSSION

The study is the first to assess the effect of a cardiac rehabilitation programme designed for patients with IC. The study will describe how to monitor and improve rehabilitation programmes for patients with IC in a real-world setting. Mixed-method strategies can allow for both exploration and generalisation in the same study, but the research design is a complex intervention and any effects found cannot be awarded a specific component.

TRIAL REGISTRATION

Retrospectively registered in Clinicaltrials.gov identifier: NCT03730623.

[Profundoplasty in treatment of patients with chronic lower limb ischaemia]

Occlusion of the superficial femoral artery is a frequently encountered pathology in peripheral vascular disease. In patients with chronic lower limb ischaemia in a lesion of crural arteries the results of femoropopliteal bypass grafting are unsatisfactory, therefore, the deep femoral artery becomes the decisive collateral pathway for perfusion of the lower extremity.

PATIENTS AND METHODS

The study included a total of 166 patients presenting with TASC II B, C and D type lesions of the femoropopliteal segment after profundoplasty, who were subdivided into 3 groups depending on the stage of chronic lower limb ischaemia: Group 1 - 95 patients with stage II B, Group 2 - 56 patients with stage III, and Group 3 - 15 patients with stage IV.

RESULTS

Five years after profundoplasty in Group 1 amputation was avoided in 90 patients (94.7%) in Group 2 - in 47 patients (83.9%), where p=0.028. During 14 months in Group 3 due to unsatisfactory distal bed 15 patients (100%) were subjected to amputation of the operated lower limb at various levels. The binary logistic regression analysis of the diameter of the deep femoral artery (p=0.045, OR=0.139) and the state of the distal arterial bed (p=0.02, OR=9.341) demonstrated that the diameter of the artery directly influenced the outcome of profundoplasty within up to 5 years.

CONCLUSION

Profundoplasty is an effective operation from the point of view of clinical and haemodynamic outcomes for patients presenting with occlusion of the superficial femoral artery and stenosis of the deep femoral artery with stage IIB and III chronic lower limb ischaemia. The diameter of the deep femoral artery and the condition of the arterial bed are the factors influencing the results of profundoplasty within up to 5 years.

MicroRNA-125a-3p affects smooth muscle cell function in vascular stenosis

AIMS

Many studies have indicated that microRNAs are closely related to the process of peripheral arterial disease (PAD). Previously, we found that microRNA-125a-3p (miR-125a-3p) in restenotic arteries after interventional therapy of lower extremity vessels was notably decreased compared with that of normal control arteries. However, its role in the development of vascular stenosis is not yet clearly understood. The purpose of this study was to investigate the expression, regulatory mechanism and function of miR-125a-3p in the process of vascular stenosis.

METHODS AND RESULTS

Quantitative reverse-transcription polymerase chain reaction assays indicated that miR-125a-3p in restenotic arteries after interventional therapy was significantly lower than that in normal control arteries. Immunofluorescence and in situ hybridization co-staining assays in arterial sections demonstrated that miR-125a-3p was mainly expressed in the medial smooth muscle layer. Transfection of miR-125a-3p mimics into cultured vascular smooth muscle cells (VSMCs) effectively inhibited cell proliferation and migration. Then, western blot and luciferase activity assays showed that recombinant human mitogen-activated protein kinase 1 (MAPK1) was a functional target of miR-125a-3p and was involved in miR-125a-3p-mediated cell effects. Finally, the lentiviral infection of miR-125a-3p in balloon-injured rat carotid vascular walls showed that miR-125a-3p overexpression significantly reduced the probability of neointimal membrane production.

CONCLUSIONS

miR-125a-3p can effectively inhibit the function of VSMCs and the occurrence of vascular stenosis by targeting MAPK1. This study introduces a new molecular mechanism of PAD. We show that regulation of the miR-125a-3p level has the potential to provide a new treatment for PAD and other proliferative vascular diseases.

The progression rate of peripheral arterial disease in patients with intermittent claudication: a systematic review

Background

Intermittent claudication (IC) is the most common symptom of peripheral arterial disease and is generally treated conservatively due to limited prognostic evidence to support early revascularisation in the individual patient. This approach may lead to the possible loss of opportunity of early revascularisation in patients who are more likely to deteriorate to critical limb ischaemia. The aim of this review is to evaluate the available literature related to the progression rate of symptomatic peripheral arterial disease.

Methods

We conducted a systematic review of the literature in PubMed and MEDLINE, Cochrane library, Elsevier, Web of Science, CINAHL and Opengrey using relevant search terms to identify the progression rate of peripheral arterial disease in patients with claudication. Outcomes of interest were progression rate in terms of haemodynamic measurement and time to development of adverse outcomes. Two independent reviewers determined study eligibility and extracted descriptive, methodologic, and outcome data. Quality of evidence was evaluated using the Cochrane recommendations for assessing risk of bias and was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results

Seven prospective cohort studies and one retrospective cohort study were identified and included in this review with the number of participants in each study ranging from 38 to 1244. Progression rate reports varied from a yearly decrease of 0.01 in ankle-brachial pressure index (ABPI) to a yearly decrease ABPI of 0.014 in 21% of participants. Quality of evidence ranged from low to moderate mostly due to limited allocation concealment at recruitment and survival selection bias.

Conclusions

Progression of PAD in IC patients is probably underestimated in the literature due to study design issues. Predicting which patients with claudication are likely to deteriorate to critical limb ischaemia is difficult since there is a lack of evidence related to lower limb prognosis. Further research is required to enable early identification of patients at high risk of progressing to critical ischaemia and appropriate early revascularisation to reduce lower limb morbidity.

Neurogenic Claudication: a Review of Current Understanding and Treatment Options

PURPOSE OF REVIEW

With an aging population and increased prevalence of the disease, we set out to evaluate the validity of current diagnostic criteria for neurogenic claudication as well as the efficacy of the treatment options for the main cause, lumbar spinal stenosis (LSS).

RECENT FINDINGS

Epidural steroid injections (ESI) were most efficacious when the injectate is a steroid combined with lidocaine or lidocaine only. There are promising results regarding the efficacy of the minimally invasive lumbar decompression (MILD) procedure as well as interspinous process spacers (IPS) compared to surgical alternatives. Spinal cord stimulators are gaining ground as an effective alternative to surgery in patients with lumbar spinal stenosis that is not responsive to conservative measures or epidural injections. We found that there continues to be a lack of consensus on the diagnostic criteria, management, and treatment options for patients with LSS. The Delphi consensus is the most current recommendation to assist clinicians with making the diagnosis. Physical therapy, NSAIDs, gabapentin, and other conservative therapy measures are unproven in providing long-lasting relief. In patients with radicular symptoms, an ESI may be indicated when a combination of lidocaine with steroids is used or using lidocaine alone. In addition, there is not enough high-quality evidence to make a recommendation regarding the use of MILD versus interspinous spacers for neurogenic claudication. There remains a need for high-quality evidence regarding the efficacy of different conservative treatments, interventional procedures, and surgical outcomes in patients with neurogenic claudication in LSS.

Supervised exercise therapy and revascularization: Single-center experience of intermittent claudication management

Guidelines recommend supervised exercise therapy (SET) as first-line treatment for intermittent claudication. However, the use of revascularization is widespread. We addressed the effectiveness of preventing (additional) invasive revascularization after primary SET or revascularization based on lesion and patient characteristics. In this single-center, retrospective, cohort study, 474 patients with intermittent claudication were included. Patients with occlusive disease of the aortoiliac tract and/or common femoral artery (inflow) were primarily considered for revascularization, while patients with more distal disease (outflow) were primarily considered for SET. In total, 232 patients were referred for SET and 242 patients received revascularization. The primary outcome was freedom from (additional) intervention, analyzed by Kaplan–Meier estimates. Secondary outcomes were survival, critical ischemia, freedom from target lesion revascularization (TLR), and an increase in maximum walking distance. In the SET-first strategy, 71% of patients had significant outflow lesions. Freedom from intervention was 0.90 ± 0.02 at 1-year and 0.82 ± 0.03 at 2-year follow-up. In the primary revascularization group, 90% of patients had inflow lesions. Freedom from additional intervention was 0.78 ± 0.03 at 1-year and only 0.65 ± 0.04 at 2-year follow-up, despite freedom from TLR of 0.91 ± 0.02 and 0.85 ± 0.03 at 1- and 2-year follow-up, respectively. In conclusion, SET was effective in preventing invasive treatment for patients with mainly outflow lesions. In contrast, secondary intervention rates following our strategy of primary revascularization for inflow lesions were unexpectedly high. These findings further support the guideline recommendations of SET as first-line treatment for all patients with intermittent claudication irrespective of level of disease.

Mobile educational follow-up application for patients with peripheral arterial disease

OBJECTIVE

to describe the development of a prototype mobile educational application for nursing follow-up aimed at patients diagnosed with peripheral arterial disease.

METHOD

a prototype-based technological production study. The construction followed the contextualized instructional design model using two steps: analysis and design and development.

RESULTS

the pedagogical content of the application was based on a survey of needs of patients with Peripheral Arterial Disease and treatments recommended in the literature. The prototype developed contained concepts, risk factors, signs and symptoms, treatment, importance of medications and their side effects, frequent doubts, necessary health care, and follow-up of patients by monitoring the evolution of the cicatricial process of lesions and possible complications, clarification of doubts and stimulus for continuation of treatment.

CONCLUSION

the use of health applications is a technological tool with the potential to improve the follow-up of patients regarding the progress of the disease and self-care, monitoring of risk factors, co-participation of the patient in the treatment, family participation, as well as planning of individualized care, and cost reduction for the health system.

Endovascular treatment for the common femoral artery: is there a challenger to open surgery?

Common femoral artery (CFA) atherosclerotic lesions currently remain one of the last limitations for adoption of endovascular repair as the first-line treatment. The bulky, eccentric, heavily calcified character of the CFA plaques, frequent involvement of the femoral bifurcation, easy surgical accessibility and last but not least, favorable long-term outcomes still make CFA disease treatment part of the surgical domain. In the last 5 years, improvement of the endovascular equipment and technical skills of the operators have led to an increase in percutaneous CFA procedures. Especially the vascular mimetic implant Supera Peripheral Stent system (Abbott Vascular), with its extreme crush resistance (if correctly implanted), seems to be an ideal tool to deal with eccentric calcified plaques, crush risk and maintaining access possibilities. The multicentric, prospective, single arm VMI-CFA Trial evaluates the outcome of treatment of symptomatic (Rutherford 2-4) CFA stenotic or occlusive lesions with the Supera Peripheral Stent System. A 6-month cumulative primary patency rate of 100% is noticed, up to 210 days. The cumulative freedom from TLR rate is 100%. Four patients died, not procedure or device related. From a clinical point of view, a tremendous switch from Rutherford 2-4 towards Rutherford 0-1 happened. No procedure nor device related adverse events are noticed. These short-term data confirm the safety and feasibility of an endovascular approach with the Supera stent to the "no-stent zone" CFA. Of course 12- and 24-month data are essential to bring more clarification in this interesting field.

Long-lasting anti-platelet activity of cilostazol from poly(ε-caprolactone)-poly(ethylene glycol) blend nanocapsules

Cilostazol (CLZ) acts as a vasodilator and antiplatelet agent and is the main drug for the treatment of intermittent claudication (IC) related to peripheral arterial disease (PAD). The usual oral dose is 100 mg twice a day, which represents a disadvantage in treatment compliance. CLZ presents several side effects, such as headache, runny nose, and dizziness. This paper aimed to obtain novel polymeric nanocapsules prepared from poly(ε-caprolactone)-poly(ethylene glycol) (PCL-PEG) blend containing CLZ. Nanocapsules showed pH values between 6.1 and 6.3, average size lower than 137 nm, low polydispersity index (<0.22) and negative zeta potential. These nanoformulations demonstrated spherical shape with smooth surface. Results achieved by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) indicated drug amorphization compared to pure CLZ. Fourier-transformed infrared spectroscopy (FTIR) showed no chemical bonds between drug and polymers. Formulations presented suitable stability for physical parameters. The in vitro drug release demonstrated prolonged release with no burst effect. Drug release was controlled by both mechanisms of polymer relaxation/degradation and Fickian diffusion. Moreover, chosen CLZ-loaded nanocapsules provided an in vivo prolonged antiplatelet effect for CLZ statistically similar to aspirin. These formulations can be further used as a feasible oral drug delivery carrier for controlled release of CLZ in order to treat PAD and IC events.

Effects of a 12-Week mHealth Program on FunctionalCapacity and Physical Activity in Patients With PeripheralArtery Disease

Supervised exercise is beneficial for peripheral artery disease (PAD) patients limited by intermittent claudication (IC). However, supervised exercise for PAD remains widely underutilized. Mobile health (mHealth) provides an intermediate solution between supervised and independent home-based exercise. The purpose of this study was to determine the effects on functional capacity and physical activity patterns of a 12-week mHealth program in PAD patients with IC. Twenty patients were randomized into usual care or a 12-week mHealth intervention consisting of patient education, smartphones, and physical activity trackers. Patient education was disseminated through smartphone and a daily exercise prescription was given based on steps per day. Primary outcomes were 12-week changes in peak VO₂ and claudication onset time; and changes in physical activity measured by steps per/day and minutes of exercise per/week. mHealth patients significantly increased peak VO₂ from 15.2 ± 4.3 to 18.0 ± 4.8 ml/kg/min (20.3 ± 26.4%; p ≤0.05), while usual care did not change from 14.3 ± 5.4 to 14.5 ± 5.7 ml/kg/min (1.0 ± 6.9%; NS). Comparison of these changes resulted in a significant difference between groups (p ≤0.05) for peak VO₂. Claudication onset time significantly increased in mHealth (320 ± 226 to 525 ± 252 seconds; ≤ 0.05), while usual care demonstrated a worsening (252 ± 256 to 231 ± 196 seconds; NS). The comparison of these group changes resulted in a significant difference (p ≤0.05). Neither steps per day or minutes of activity reached significant differences between groups. In conclusion, a 12-week mHealth program in PAD patients with IC can improve peak VO₂ and claudication onset time; and mHealth interventions represent a promising alternative therapy for those patients who cannot participate in supervised exercise.

Optimal medical management before lower extremity bypass for claudication in the veteran population

OBJECTIVE

Optimizing medical management through glucose control, smoking cessation, and drug therapy (ie, antiplatelet and statin agents) is recommended as first-line therapy for patients with claudication. The aims of this study were to determine how frequently veterans with claudication received optimal medical management (OMM) before undergoing elective open lower extremity bypass procedures nationwide and whether preoperative OMM was associated with improved surgical outcomes.

METHODS

We reviewed all patients within the Veterans Affairs (VA) Surgical Quality Improvement Program database who underwent elective open lower extremity bypass procedures for claudication at nationwide VA medical centers from 2005 until 2015. We defined OMM as a claudicant's having documentation of receiving all of the following within 12 months before surgery: prescriptions for antiplatelet, statin, and smoking cessation therapy (if a smoker) and monitoring of hemoglobin A_1c (if diabetic). Outcome measures included occurrence of any 30-day VA Surgical Quality Improvement Program complication, amputation-free survival, and 30-day and 1-year mortality. We used multivariate regression and Cox proportional hazards models incorporating inverse probability treatment weighting to analyze the effect of OMM on outcome measures after adjusting for patient-level confounding.

RESULTS

Among 10,271 lower extremity bypass procedures performed, 2265 (22%) were undertaken in claudicants with a median age of 63 years (interquartile range, 58-68 years). Of claudicants, 839 (37%) were diabetic, and 1333 (59%) patients smoked within 12 months before surgery. OMM was achieved in only 581 (26%) claudicants before they underwent surgery, although adherence to individual components was variable: antiplatelet, 55%; statin, 63%; smoking cessation, 58%; and hemoglobin A_1c monitoring, 92%. In risk-adjusted analyses, there were no statistically significant differences in complication rates, amputation-free survival, or mortality outcomes among patients who received OMM compared with non-OMM patients.

CONCLUSIONS

Only a quarter of veterans with claudication were documented as receiving OMM within the year before undergoing open lower extremity bypass across nationwide VA medical centers, highlighting the need for strategies to ensure that medical therapy is intensified before surgical revascularization. Nevertheless, our data showed that documentation of preoperative OMM did not lead to improved short- or long-term postoperative outcomes in these patients, suggesting that more objective measures of medical management are needed to ensure that peripheral arterial disease goals are achieved.

Microfibrillar-associated protein 4 variation in symptomatic peripheral artery disease

Background

Symptomatic peripheral artery disease (PAD) is an atherosclerotic occlusive disease affecting the lower extremities. The cause of symptomatic PAD is atherosclerosis, vascular dysfunctions, impaired angiogenesis and neointima formation. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein, which is highly expressed in the heart and arteries and recently introduced as a potential mediator of pathological vascular remodeling and neointima formation. We aimed to investigate the relationship between serum MFAP4 (sMFAP4) and symptomatic PAD outcomes.

Methods

A total of 286 PAD patients were analyzed if they had either intermittent claudication or critical lower-extremity ischemia (CLI) and followed for 7 years. The level of serum MFAP4 (sMFAP4) was measured by alphaLISA. Kaplan–Meier, Cox proportional hazard and logistic regression analysis were used to analyze the associations between upper tertile sMFAP4 and symptomatic PAD outcomes.

Results

Patients with upper tertile sMFAP4 had an odds ratio (OR) of 2.65 (p < 0.001) for having CLI diagnosis. Further analysis indicated that patients with upper tertile sMFAP4 had a hazard ratio (HR) of 1.97 (p = 0.04) for cardiovascular death during the 7-years follow-up. However, analysis of 2-year primary patency showed that patients with upper tertile sMFAP4 had decreased risk of vascular occlusion after reconstructive surgery with HR of 0.15 (p = 0.02).

Conclusions

sMFAP4 has potential as a prognostic marker for cardiovascular death, primary patency of reconstructed vessels and CLI diagnosis in symptomatic PAD patients. Confirmation of observations in larger cohorts is warranted.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1523-6) contains supplementary material, which is available to authorized users.

Peripheral Arterial Disease in Women: an Overview of Risk Factor Profile, Clinical Features, and Outcomes

Purpose of Review

Peripheral arterial disease (PAD) is the third most common manifestation of cardiovascular disease (CVD), following coronary artery disease (CAD) and stroke. PAD remains underdiagnosed and under-treated in women.

Recent Findings

Women with PAD experience more atypical symptoms and poorer overall health status. The prevalence of PAD in women increases with age, such that more women than men have PAD after the age of 40 years. There is under-representation of PAD patients in clinical trials in general and women in particular. In this article, we address the lack of women participants in PAD trials. We then present a comprehensive overview of the epidemiology/risk factor profile, clinical features, treatment, and outcomes.

Summary

PAD is prevalent in women and its global burden is on the rise despite a decline in global age-standardized death rate from CVD. The importance of this issue has been underlined by the American Heart Association’s (AHA) “Call to Action” scientific statement on PAD in women. Large-scale campaigns are needed to increase awareness among physicians and the general public. Furthermore, effective treatment strategies must be implemented.