Retrograde distal access versus femoral access for below the knee angioplasty

BACKGROUND

The prevalence of peripheral artery disease (PAD) in the general population is about 12% to 14% and it increases with age. PAD increased from 164 million people in 2000 to 202 million people in 2010. More than two-thirds of people with PAD are based in low- or middle-income countries. Critical limb ischaemia (CLI) occurs in 1% to 2% of people with intermittent claudication over five years. One third of people with CLI have isolated below the knee (BTK) lesions. CLI and isolated BTK lesions are associated with a higher incidence of limb loss when compared with people with multilevel arterial disease. Endovascular procedures such as angioplasty (with or without stenting) are widely used to treat isolated BTK lesions, aiming to improve blood flow and limb salvage. The technical success of any angioplasty procedure depends on the ability to cross the target lesion. Failed attempts are underestimated in the literature and failures in the real world appear to be higher than reported. People with isolated BTK lesions undergoing angioplasty by conventional femoral access present a high failure rate to cross these lesions. Retrograde distal access may provide some advantages that can lead to successful crossing of the target lesion.

OBJECTIVES

To evaluate the benefits and harms of retrograde distal access versus conventional femoral access for people undergoing below the knee angioplasty.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases, and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 26 September 2022.

SELECTION CRITERIA

We planned to include randomised or quasi-randomised controlled trials comparing people undergoing retrograde distal access versus people undergoing conventional femoral access (ipsilateral antegrade or contralateral retrograde) for BTK angioplasty.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed identified studies for potential inclusion in the review. We used standard methodological procedures in accordance with the Cochrane Handbook for Systematic Review of Interventions. Our primary outcomes were technical success of angioplasty procedure and major procedural complications. Our secondary outcomes were mortality rate, amputation-free survival, primary patency, minor procedural complications and wound healing. We planned to use GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We identified no randomised or quasi-randomised controlled trials that met the inclusion criteria.

AUTHORS' CONCLUSIONS

We identified no randomised or quasi-randomised controlled trials that compared retrograde distal access versus femoral access for BTK angioplasty. High-quality studies that compare retrograde distal access versus conventional femoral access for BTK angioplasty are needed.

Robust critical limb ischemia porcine model involving skeletal muscle necrosis

This work sought to develop a robust and clinically relevant swine model of critical limb ischemia (CLI) involving the onset of ischemic muscle necrosis. CLI carries about 25-40% risk of major amputation with 20% annual mortality. Currently, there is no specific treatment that targets the ischemic myopathy characteristic of CLI. Current swine models of CLI, with tolerable side-effects, fail to achieve sustained ischemia followed by a necrotic myopathic endpoint. Such limitation in experimental model hinders development of effective interventions. CLI was induced unilaterally by ligation-excision of one inch of the common femoral artery (CFA) via infra-inguinal minimal incision in female Yorkshire pigs (n = 5). X-ray arteriography was done pre- and post-CFA transection to validate successful induction of severe ischemia. Weekly assessment of the sequalae of ischemia on limb perfusion, and degree of ischemic myopathy was conducted for 1 month using X-ray arteriography, laser speckle imaging, CTA angiography, femoral artery duplex, high resolution ultrasound and histopathological analysis. The non-invasive tissue analysis of the elastography images showed specific and characteristic pattern of increased muscle stiffness indicative of the fibrotic and necrotic outcome expected with associated total muscle ischemia. The prominent onset of skeletal muscle necrosis was evident upon direct inspection of the affected tissues. Ischemic myopathic changes associated with inflammatory infiltrates and deficient blood vessels were objectively validated. A translational model of severe hindlimb ischemia causing ischemic myopathy was successfully established adopting an approach that enables long-term survival studies in compliance with regulatory requirements pertaining to animal welfare.

Stem Cell Therapy in Critical Limb Ischemia

Critical limb ischemia (CLI), a serious outcome of peripheral artery disease, is frequently associated with morbid outcomes. The available treatment modalities do not provide satisfactory results, leading to marked morbidities such as joint contracture and amputations, resulting in a high economic burden. The peripheral vascular disease tends to cause more morbidity in patients with diabetes and atherosclerosis, given the pre-existing compromised perfusion of medium and small vessels in diabetic patients. With surgical procedures, the chance of vascular compromise further increases, inducing a significantly greater rate of amputation. Hence, the need for nonsurgical treatment modalities such as stem cell therapy (SCT), which promotes angiogenesis, is warranted. In CLI, SCT acts through neovascularization and the development of collateral arteries, which increases blood supply to the soft tissues of the ischemic limb, providing satisfactory outcomes. An electronic database search was performed in PubMed, SCOPUS, EMBASE, and ScienceDirect to identify published clinical trial data, research studies, and review articles on stem cell therapy in critical limb ischemia. The search resulted in a total of 2391 results. Duplicate articles screening resulted in 565 articles. In-depth screening of abstracts and research titles excluded 520 articles, yielding 45 articles suitable for full-text review. On review of full text, articles with overlapping and similar results were filtered, ending in 25 articles. SCT promotes arteriogenesis, and bone marrow-derived mesenchymal stromal cells produce significant effects like reduced morbidity, improved amputation-free survival (AFS ) rate, and improved distal perfusion even in "no-option" CLI patients. SCT is a promising treatment modality for CLI patients, even in those in whom endovascular and revascularization procedures are impossible. SCT assures a prolonged AFS rate, improved distal perfusion, improved walking distances, reduced amputation rates, and increased survival ratio, and is well-tolerated.

Synergic Effect of Combined Therapy of Hyperbaric Oxygen and Adipose-Derived Mesenchymal Stem Cells on Improving Locomotor Recovery After Acute Traumatic Spinal Cord Injury in Rat Mainly Through Downregulating Inflammatory and Cell-Stress Signalings

This study tested whether combined hyperbaric oxygen (HBO) and allogenic adipose-derived mesenchymal stem cells (ADMSCs) would be superior to either one for improving the locomotor recovery in rat after acute traumatic spinal cord injury (TSCI) in rat. Adult-male Sprague-Dawley rats were equally categorized into group 1 (sham-operated control), group 2 (TSCI), group 3 (TSCI + HBO for 1.5 h/day for 14 consecutive days after TSCI), group 4 (TSCI + ADMSCs/1.2 × 10⁶ cells by intravenous injection at 3 h and days 1/2 after TSCI), and group 5 (TSCI + HBO + ADMSCs), euthanized, and spinal cord tissue was harvested by day 49 after TSCI. The protein expressions of oxidative-stress (NOX-1/NOX-2), inflammatory-signaling (TLR-4/MyD88/IL-1β/TNF-α/substance-p), cell-stress signaling (PI3K/p-AKT/p-mTOR), and the voltage-gated sodium channel (Nav1.3/1.8/1.9) biomarkers were highest in group 2, lowest in group 1, and significantly lower in group 5 than in groups 3/4 (all <i>P</i> &lt;0.0001), but they did not differ between groups 3 and 4. The spinal cord damaged area, the cellular levels of inflammatory/DNA-damaged biomarkers (CD68+/GFAP+/γ-H2AX+ cells), mitogen-activated protein kinase family biomarkers (p-P38/p-JNK/p-ERK1/2), and cellular expressions of voltage-gated sodium channel (Nav.1.3, Nav.1.8, and Nav.1.9 in NF200+ cells) as well as the pain-facilitated cellular expressions (p-P38+/peripherin+ cells, p-JNK+/peripherin+ cells, p-ERK/NF200+ cells) exhibited an identical pattern of inflammation, whereas the locomotor recovery displayed an opposite pattern of inflammation among the groups (all <i>P</i> &lt; 0.0001). Combined HBO-ADMSCs therapy offered additional benefits for preserving the neurological architecture and facilitated the locomotor recovery against acute TSCI.

Orthopedic Surgery Referral Pattern Analysis per Demographic Factors Among Patients Diagnosed With Severe Peripheral Artery Disease in Terms of Partial or Total Limb Amputation

Introduction: Peripheral artery disease (PAD) signifies the obstruction of blood vessels in the lower extremities due to harmful buildup of fatty material. Patients may present to their primary care provider complaining of lower extremity pain, especially during exercise. Primary care providers must weigh the severity of patients’ disease process to determine if an orthopedic surgery referral is needed based on an extensive history as well as analysis of demographic factors that may influence their risk of morbidity and mortality. We aimed to objectively present these demographic factors with numeric values in terms of influence.

Methods: We utilized the Cerner Health Facts database to analyze 63 million unique patient encounters from 2000 to 2018. The database is categorized as Institutional Review Board (IRB) exempt due to its de-identified presentation. In an outcome-based approach, we were able to calculate referral patterns based on entered demographic parameters.

Results: A patient’s age, census region, marital status, previous history of PAD/critical limb ischemia (CLI), history of surgeries, race, facility type, and urban/rural status presented as predictors of seeing a surgeon during a patient encounter.

Conclusion: Our results found numerous aforementioned demographic factors to be associated with orthopedic surgery referral patterns. This is significant as proper reconciliation of these factors may help reduce patient morbidity in terms of amputation reduction and reduce patient mortality associated with this surgery or complications.

Analysis of Interwoven Nitinol Stenting for the Treatment of Critical Limb Ischemia: Outcomes From an Average 3-Year Follow-up Period

We assessed the clinical outcomes of patients with critical limb-threatening ischemia (CLTI) who underwent interwoven nitinol stent (Supera) implantation for significant stenoses of the femoropopliteal segment. In this retrospective cohort study, 116 consecutive patients with CLTI who were treated with Supera stents between September 2015 and March 2020 were included in this analysis. Primary endpoint analysis was completed for amputation-free survival, target lesion revascularization (TLR), and mortality. After a mean follow-up time of 3.4 years, 21 (18%) patients had undergone amputations, 3 (2.6%) died, and, overall, the amputation-free survival rate was 81%. TLR occurred in 21 (18%) patients, resulting in the freedom from target lesion revascularization of 82%. The average Wagner score for all patients was 2.8 ± 1.1. A subgroup analysis of 57 patients revealed a median ulcer size of 3.0 cm² [1.65, 9.0], with complete healing for 45 patients by 20 months. The Wagner score of this subgroup decreased by an average of 3.4 ± .9 points. Supera stents can be used together with other endovascular therapies and are a safe and effective treatment modality for CLTI.

Hand osteomyelitis in arterial calcification, diabetes mellitus and end-stage renal failure: a comparison of 210 cases over 12 years

We present 210 patients with hand osteomyelitis in 246 rays over 12 years, including detailed analysis of 29 patients in this cohort with digital artery calcification evident on plain X-ray. Overall 71 patients had diabetes mellitus and/or end-stage renal failure, including 28 of 29 patients with calcification. In the calcification group, 17 patients had ipsilateral arteriovenous fistulae, five had steal syndrome and 15 had digital ulceration or skin necrosis. Compared with 181 controls, patients with calcification had more affected bones, polymicrobial infections, surgical procedures, phalanges and digits amputated and had higher mortality at 1 year (12 of 29) and 5 years (20 of 29), as a result of comorbidities. Absence of calcification in 43 patients with diabetes and/or end-stage renal failure was associated with better outcomes on all the above parameters. Early amputation to maximize disease-free survival may be appropriate for patients with hand osteomyelitis and arterial calcification.Level of evidence: IV.

Improving Symptoms of Peripheral Artery Disease With Hirudotherapy

Peripheral artery disease (PAD) is a significant cause of morbidity and mortality in the world. Critical limb ischemia is a complication of PAD that leads to severe pain at rest, numbness, and absent or diminished pulses in the legs or feet. Revascularization with surgery or endovascular intervention is required to re-establish blood flow to the affected areas. Failure to respond to medical and/or surgical treatment can lead to amputations. The decision to amputate one’s limb can be very challenging. Here, we report a patient with critical limb ischemia who refused a below-the-knee amputation and self-treated with medicinal leech therapy, or hirudotherapy. His symptoms including his pain, burning, and numbness improved significantly following six months of therapy.

Systematic review of inframalleolar endovascular interventions and rates of limb salvage, wound healing, restenosis, rest pain, reintervention and complications

Objectives

Peripheral artery disease is estimated to affect 237 million individuals worldwide. Critical limb ischaemia, also known as chronic limb threatening ischaemia is a consequence of the progression of peripheral artery disease which occurs in ∼21% of patients over a five-year period. The aim of this systematic review is to assess the use of additional below-the-ankle angioplasty in comparison to the use of above-the-ankle angioplasty alone, and the subsequent rates of amputation, wound healing, restenosis, rest pain, reintervention and complications.

Methods

This systematic review was undertaken in accordance with PRISMA guidelines following a registered protocol (CRD42019154893). Online databases were searched using a search strategy of 20 keywords. Included articles reported the outcome for inframalleolar (pedal artery, pedal arch, plantar arteries) angioplasty with additional proximal angioplasty in comparison to proximal angioplasty alone. GRADE assessment was applied to assess the quality of the evidence.

Results

After screening 1089 articles, 10 articles met the inclusion criteria. Comparative performance assessment of below-the-ankle with above-the-ankle versus above-the-ankle angioplasty alone was undertaken in 3 articles, with the remaining 7 articles reporting outcomes of below-the-ankle with above-the-ankle angioplasty with no distinct comparator group. Significant decrease in major lower limb amputation at the last follow-up in the below-the-ankle group when compared with the above-the-ankle angioplasty alone group was observed in a single study (3.45% vs. 14.9%, p < 0.05). Improved wound healing rate at follow-up in the below-the-ankle group versus above-the-ankle angioplasty alone group was also reported in a single study (59.3% vs. 38.1%, p < 0.05). Subsequent rate of amputation after below-the-ankle angioplasty has been estimated as 23.5%.

Conclusion

To date, there is a lack of studies assessing inframalleolar interventions and their use in improving limb salvage, wound healing and symptomatology. Prospective RCTs should be undertaken with adequate participant numbers to be sufficiently powered and report clinically important end-points.

Malaysian clinical practice guidelines for management of diabetic foot: A synopsis for the primary care physician

Diabetic foot requires careful attention and coordinated management by a dedicated team. Screening, prevention, adequate assessment, and appropriate referral are crucial to prevent complications. Multimodal treatment and rehabilitation are recommended to ensure a better quality of life and reduction of amputation rate in people with diabetic foot.

Circulatory Rejuvenated EPCs Derived from PAOD Patients Treated by CD34+ Cells and Hyperbaric Oxygen Therapy Salvaged the Nude Mouse Limb against Critical Ischemia

This study tested whether circulatory endothelial progenitor cells (EPCs) derived from peripheral arterial occlusive disease (PAOD) patients after receiving combined autologous CD34+ cell and hyperbaric oxygen (HBO) therapy (defined as rejuvenated EPCs) would salvage nude mouse limbs against critical limb ischemia (CLI). Adult-male nude mice (n = 40) were equally categorized into group 1 (sham-operated control), group 2 (CLI), group 3 (CLI-EPCs (6 × 10⁵) derived from PAOD patient’s circulatory blood prior to CD34⁺ cell and HBO treatment (EPC^Pr-T) by intramuscular injection at 3 h after CLI induction) and group 4 (CLI-EPCs (6 × 10⁵) derived from PAOD patient’s circulatory blood after CD34⁺ cell and HBO treatment (EPC^Af-T) by the identical injection method). By 2, 7 and 14 days after the CLI procedure, the ischemic to normal blood flow (INBF) ratio was highest in group 1, lowest in group 2 and significantly lower in group 4 than in group 3 (p < 0.0001). The protein levels of endothelial functional integrity (CD31/von Willebrand factor (vWF)/endothelial nitric-oxide synthase (eNOS)) expressed a similar pattern to that of INBF. In contrast, apoptotic/mitochondrial-damaged (mitochondrial-Bax/caspase-3/PARP/cytosolic-cytochrome-C) biomarkers and fibrosis (Smad3/TGF-ß) exhibited an opposite pattern, whereas the protein expressions of anti-fibrosis (Smad1/5 and BMP-2) and mitochondrial integrity (mitochondrial-cytochrome-C) showed an identical pattern of INBF (all p < 0.0001). The protein expressions of angiogenesis biomarkers (VEGF/SDF-1α/HIF-1α) were progressively increased from groups 1 to 3 (all p < 0.0010). The number of small vessels and endothelial cell surface markers (CD31⁺/vWF⁺) in the CLI area displayed an identical pattern of INBF (all p < 0.0001). CLI automatic amputation was higher in group 2 than in other groups (all p < 0.001). In conclusion, EPCs from HBO-C34+ cell therapy significantly restored the blood flow and salvaged the CLI in nude mice.

Temporal trends and outcomes of critical limb ischemia among patients with chronic kidney disease

There is a paucity of data on the outcomes and revascularization strategies for critical limb ischemia (CLI) among patients with chronic kidney disease (CKD). Hence, we conducted a nationwide analysis to evaluate the trends and outcomes of hospitalizations for CLI with CKD. The National Inpatient Sample database (2002-2015) was queried for hospitalizations for CLI. The trends of hospitalizations for CLI with CKD were reported, and endovascular versus surgical revascularization strategies for CLI with CKD were compared. The main study outcome was in-hospital mortality. The analysis included 2,139,640 hospitalizations for CLI, of which 484,224 (22.6%) had CKD. There was an increase in hospitalizations for CLI with CKD (P_trend = 0.01), but a reduction in hospitalizations for CLI without CKD (P_trend = 0.01). Patients with CLI and CKD were less likely to undergo revascularization compared with patients without CKD. CLI with CKD had higher rates of in-hospital mortality (4.8% vs 2.5%, adjusted odds ratio (OR) 2.01; 95% CI 1.93-2.11) and major amputation compared with no CKD. Revascularization for CLI with CKD was associated with lower rates of mortality (3.7% vs 5.3%, adjusted-OR 0.78; 95% CI 0.72-0.84) and major amputation compared with no revascularization. Compared with endovascular revascularization, surgical revascularization for CLI with CKD was associated with higher rates of in-hospital mortality (4.7% vs 2.7%, adjusted-OR 1.67; 95% CI 1.43-1.94). In conclusion, this contemporary observational analysis showed an increase in hospitalizations for CLI among patients with CKD. CLI with CKD was associated with higher in-hospital mortality compared with no CKD. Compared with endovascular therapy, surgical revascularization for CLI with CKD was associated with higher in-hospital mortality.

[Problems and prospects of cell therapy for critical ischaemia of lower limbs]

BACKGROUND

Cell therapy was proposed as a procedure of indirect revascularization for patients with critical ischaemia of lower extremities for whom endovascular and surgical revascularization is impossible. We present herein a review of the state of the art of studies in the field of cell therapy of this cohort of patients.

BASIC PROVISIONS

Cell therapy has proved safe, however, the results of studies of efficacy are relatively ambiguous and unconvincing. The number of patients in separately taken clinical trials is minimal. The reviewed studies differed not only by heterogeneity of the cell types used but by the routes of administration of cells (cells were delivered either intramuscularly (predominantly) or intraarterially) and the duration of follow up (time of assessment and duration of follow up varied from 1 month to 2 years). One of the problems became the lack of the routine study of the angiogenic potential of stem cells prior to their clinical application. It is known that the angiogenic activity of multipotent cells of apparently healthy patients may differ from that of patients suffering from atherosclerosis, chronic renal failure, diabetes.

CONCLUSIONS

It is supposed that treatment with stem cells or precursor cells is more efficient as compared to protein or gene therapy not only owing to direct vasculogenic properties but a paracrine action through excretion of proangiogenic biologically active substances. More studies with larger cohorts are necessary to provide stronger safety and efficacy data on cell therapy. Besides, a promising trend in the field of cellular approaches is modulation of regenerative capability of stem cells, which may help overcome difficulties in understanding the place of cell therapy in therapeutic angiogenesis.

The Role of Lower Extremity Amputation in Chronic Limb-Threatening Ischemia

Chronic limb-threatening ischemia (CLTI) is a severe form of peripheral artery disease associated with high rates of limb loss. The primary goal of treatment in CLTI is limb salvage via revascularization. Multidisciplinary teams provide improved care for those with CLTI and lead to improved limb salvage rates. Not all patients are candidates for revascularization, and a subset will require major amputation. This article highlights the role of amputations in the management of CLTI, and describes the patients who should be offered primary amputation.

The Role of Angiogenesis-Inducing microRNAs in Vascular Tissue Engineering

Angiogenesis is an important process in tissue repair and regeneration as blood vessels are integral to supply nutrients to a functioning tissue. In this review, the application of microRNAs (miRNAs) or anti-miRNAs that can induce angiogenesis to aid in blood vessel formation for vascular tissue engineering in ischemic diseases such as peripheral arterial disease and stroke, cardiac diseases, and skin and bone tissue engineering is discussed. Endothelial cells (ECs) form the endothelium of the blood vessel and are recognized as the primary cell type that drives angiogenesis and studied in the applications that were reviewed. Besides ECs, mesenchymal stem cells can also play a pivotal role in these applications, specifically, by secreting growth factors or cytokines for paracrine signaling and/or as constituent cells in the new blood vessel formed. In addition to delivering miRNAs or cells transfected/transduced with miRNAs for angiogenesis and vascular tissue engineering, the utilization of extracellular vesicles (EVs), such as exosomes, microvesicles, and EVs collectively, has been more recently explored. Proangiogenic miRNAs and anti-miRNAs contribute to angiogenesis by targeting the 3'-untranslated region of targets to upregulate proangiogenic factors such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor, and hypoxia-inducible factor-1 and increase the transduction of VEGF signaling through the PI3K/AKT and Ras/Raf/MEK/ERK signaling pathways such as phosphatase and tensin homolog or regulating the signaling of other pathways important for angiogenesis such as the Notch signaling pathway and the pathway to produce nitric oxide. In conclusion, angiogenesis-inducing miRNAs and anti-miRNAs are promising tools for vascular tissue engineering for several applications; however, future work should emphasize optimizing the delivery and usage of these therapies as miRNAs can also be associated with the negative implications of cancer.

Thermographic Characterization of Cutaneous Ulcers of Different Etiologies

The characterization of the temperature of skin ulcers may provide preliminary diagnostic evidence. The aim of this study was to characterize cutaneous ulcers of different etiologies by infrared thermography. 122 cutaneous ulcers of 87 patients (age 60.1 ± 15.7 years) were evaluated, allocated into five groups: venous ulcers (VU) n = 26, arterial ulcers (AU) n = 20, mixed ulcers (MU) n = 25, pressure ulcers (PU) n = 29, and neuropathic ulcers (NU) n = 22. The cutaneous temperature was recorded by infrared thermography (FLIR-450™); we also evaluated the ulcer area, the ankle brachial index (ABI), the range of motion (ROM) of the ankle, and pain. For the different variables, the statistical analysis was performed using the Kruskal Wallis test, ANOVA, the chi-squared test, and the Spearman test (SPSS™ software version 20, p < 0.05). A significant difference was found between the temperatures of PU and NU. The ABI was significantly lower in the MU and AU groups, and pain was also higher in these groups. The ROM was decreased in all groups, and the MU and VU groups had the lowest ROM. There was no correlation between temperature and the clinical findings (ABI, ROM, and pain). There was a moderate correlation in the analysis between the temperature and the area of the ulcer in the PU group, as larger ulcers had lower temperatures. It is possible to characterize cutaneous ulcers by infrared thermography, and there are temperature differences among ulcers with different etiologies.

Combined Therapy With Hyperbaric Oxygen and Melatonin Effectively Reduce Brain Infarct Volume and Preserve Neurological Function After Acute Ischemic Infarct in Rat

This study tested the hypothesis that combined hyperbaric oxygen (HBO) and melatonin (Mel) was superior to either one for protecting the brain functional and parenchymal integrity from acute ischemic stroke (IS) injury. Adult-male Sprague-Dawley rats were divided into groups 1 (sham-operated control), 2 (IS), 3 (IS + HBO), 4 (IS + Mel), and 5 (IS + HBO-Mel). By day 28 after IS, the brain infarct area (BIA) was lowest in group 1, highest in group 2, significantly higher in groups 3 and 4 than in group 5, but not different between groups 3 and 4. The neurological function at day 7, 14, and 28 exhibited an opposite pattern to BIA among the 5 groups. The protein expressions of inflammatory (IL-1β/IL-6/iNOS/TNF-α/p-NF-κB), apoptotic (cleaved-caspase3/cleaved-PARP/mitochondrial Bax), mitochondrial/DNA-damaged (cytochrome-C/γ-H2AX), oxidative stress (NOX-1/NOX-2), and autophagy (i.e. ratio of CL3B-II/CL3B-I) biomarkers displayed an identical pattern of BIA among 5 groups. Cellular expressions of inflammation (F4/80+/GFAP+) and DNA-damaged biomarker (γ-H2AX+) exhibited an identical pattern, whereas the integrities of myelin sheath/neuron (MPB+/NeuN+), endothelial cell (CD31+/vWF+), and number of small vessels exhibited an opposite pattern of BIA among the 5 groups. Combined HBO-Mel therapy offered an additional benefit in protecting the brain against IS injury.

Lower extremity revascularization via endovascular and surgical approaches: A systematic review with emphasis on combined inflow and outflow revascularization

This review is intended to help clinicians and patients understand the present state of peripheral artery disease, appreciate the progression and presentation of critical limb ischemia/chronic limb-threatening ischemia, and make informed decisions regarding inflow and outflow endovascular revascularization and surgical treatment options within the context of current debates in the medical community. A controlled literature search was performed to obtain research on outcomes of critical limb ischemia patients undergoing complete leg revascularization for peripheral artery disease inflow and outflow disease. Data for this review were identified by queries of medical and life science databases, expert referral, and references from relevant papers published between 1997 and 2019, resulting in 48 articles. The literature review herein indicates that endovascular revascularization-including ballooning, stenting, and atherectomy-is an effective peripheral artery disease therapy for both above the knee and below the knee disease, and can safely and effectively treat both inflow and outflow disease. As such, it plays a leading role in the therapy of lower extremity artery disease.

Retrograde distal access versus femoral access for below the knee angioplasty

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To compare the effectiveness and safety of retrograde distal access versus conventional femoral access for people undergoing below the knee angioplasty.

MicroRNA-24-3p Targets Notch and Other Vascular Morphogens to Regulate Post-ischemic Microvascular Responses in Limb Muscles

MicroRNAs (miRs) regulate complex processes, including angiogenesis, by targeting multiple mRNAs. miR-24-3p-3p directly represses eNOS, GATA2, and PAK4 in endothelial cells (ECs), thus inhibiting angiogenesis during development and in the infarcted heart. miR-24-3p is widely expressed in cardiovascular cells, suggesting that it could additionally regulate angiogenesis by acting on vascular mural cells. Here, we have investigated: 1) new miR-24-3p targets; 2) the expression and the function of miR-24-3p in human vascular ECs; 3) the impact of miR-24-3p inhibition in the angiogenesis reparative response to limb ischemia in mice. Using bioinformatics target prediction platforms and 3'-UTR luciferase assays, we newly identified Notch1 and its Delta-like ligand 1 (Dll1) to be directly targeted by miR-24-3p. miR-24-3p was expressed in human ECs and pericytes cultured under normal conditions. Exposure to hypoxia increased miR-24-3p in ECs but not in pericytes. Transfection with a miR-24-3p precursor (pre-miR-24-3p) increased miR-24-3p expression in ECs, reducing the cell survival, proliferation, and angiogenic capacity. Opposite effects were caused by miR-24-3p inhibition. The anti-angiogenic action of miR-24-3p overexpression could be prevented by simultaneous adenovirus (Ad)-mediated delivery of constitutively active Notch intracellular domain (NICD) into cultured ECs. We next demonstrated that reduced Notch signalling contributes to the anti-angiogenic effect of miR-24-3p in vitro. In a mouse unilateral limb ischemia model, local miR-24-3p inhibition (by adenovirus-mediated miR-24-3p decoy delivery) restored endothelial Notch signalling and increased capillary density. However, the new vessels appeared disorganised and twisted, worsening post-ischemic blood perfusion recovery. To better understand the underpinning mechanisms, we widened the search for miR-24-3p target genes, identifying several contributors to vascular morphogenesis, such as several members of the Wingless (Wnt) signalling pathway, β-catenin signalling components, and VE-cadherin, which synergise to regulate angiogenesis, pericytes recruitment to neoformed capillaries, maturation, and stabilization of newly formed vessels. Among those, we next focussed on β-catenin to demonstrate that miR-24-3p inhibition reduces β-catenin expression in hypoxic ECs, which is accompanied by reduced adhesion of pericytes to ECs. In summary, miR-24-3p differentially targets several angiogenesis modulators and contributes to autonomous and non-autonomous EC crosstalk. In ischemic limbs, miR-24-3p inhibition increases the production of dysfunctional microvessels, impairing perfusion. Caution should be observed in therapeutic targeting of miR-24-3p.

The Controlling Nutritional Status Score is Significantly Associated with Complete Ulcer Healing in Patients with Critical Limb Ischemia

BACKGROUND

It has been reported that the Controlling Nutritional Status (CONUT) score, calculated using the serum albumin concentration, total peripheral lymphocyte count, and total cholesterol concentration, is a valuable nutritional status index. In the present study, we assessed whether the CONUT score was a significant predictor of complete ulcer healing in patients with critical limb ischemia (CLI).

METHODS

In this retrospective, single center, cohort study, conducted from January 2013 to June 2018, we treated 112 limbs of 89 patients with Fontaine 4 CLI at the Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Japan. The primary endpoint of the study was complete ulcer healing after revascularization, and the secondary endpoint was amputation-free survival (AFS).

RESULTS

The mean follow-up time was 17.8 months. Complete ulcer healing was achieved during the follow-up period in 91 (81.2%) limbs. The median ulcer healing time was 104 days (range, 16-574 days). In multivariate analysis, improvement of lower skin perfusion pressure ratio of <1, end-stage renal disease, and high CONUT score (>4) were predictive of incomplete ulcer healing in patients with Fontaine 4 CLI. In addition, the AFS rate was significantly better in patients with a CONUT score ≤4 than in those with a CONUT score >4.

CONCLUSIONS

The CONUT score was associated with postprocedure ulcer healing and long-term limb retention in patients who underwent revascularization. The management of CLI involving ischemic foot ulcers may require ongoing consideration of nutritional status.

Perioperative Outcomes of Lower Extremity Revascularization for Rest Pain and Tissue Loss

BACKGROUND

Critical limb ischemia (CLI) is the clinical manifestation of severe peripheral artery disease presenting as rest pain (RP) and tissue loss (TL). Most studies compare CLI as a homogenous group with claudication with limited database studies specifically studying these differences. We hypothesize that CLI should be stratified into RP and TL because of significant differences in disease severity, comorbidities, and outcomes.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database from 2012 to 2016 was reviewed. All patients with a postoperative diagnosis of CLI undergoing femoral to popliteal bypass (FPB) with vein or graft were identified. Patients were stratified into cohorts based on International Classification of Disease (ICD)-9 or ICD-10 codes for RP or TL (gangrene or ulcer). Univariate and multivariate analyses were performed to examine 30-day mortality, morbidity, major amputation, and readmission adjusting for demographics, comorbidities, and procedural details.

RESULTS

There were 5,304 patients. Compared to RP, patients with TL were older (P < 0.0001) and more likely to be dependent (P < 0.0001). TL patients were also more likely to have diabetes (P < 0.0001), congestive heart failure (P < 0.0001), renal failure (P = 0.004), dialysis (P < 0.0001), history of wound infection (P < 0.0001), and sepsis (P < 0.0001). TL patients had higher American Society of Anesthesiologists class (P < 0.0001), were less likely to be transferred from home (P < 0.0001), and more likely to receive an FPB with vein (P = 0.03). Patients with TL had worse perioperative outcomes compared with RP in terms of pneumonia (P = 0.004), unplanned intubation (P = 0.009), cardiac arrest requiring cardiopulmonary resuscitation (P = 0.003), bleeding requiring transfusions (P < 0.0001), sepsis (P < 0.0001), septic shock (P = 0.02), and reoperation (P < 0.0001). TL was associated with significantly higher 30-day morbidity (P < 0.0001), 30-day mortality (P < 0.0001), major amputation (P = 0.0004), and readmission rates (P = 0.005). Patients with TL compared with those with RP also had longer hospital stays (P < 0.0001) and days between operation to discharge (P < 0.0001). TL was independently associated with increased 30-day morbidity (OR: 1.16 [1.00-1.35]) and major amputation (OR: 2.48 [1.29-4.76]) compared with RP.

CONCLUSIONS

Patients with RP and TL have drastic differences that impact perioperative mortality and readmissions. TL is an independent predictor of 30-day morbidity and major amputation. The stratification of CLI into RP and TL can provide insight into variations in outcomes and provide a means to quantify the risks associated with the 2 manifestations of the disease.

Effective wound bed preparation using maggot debridement therapy for patients with critical limb ischaemia

OBJECTIVE

Patients with critical limb ischaemia (CLI) lack sufficient blood flow in to the limb, which leads to difficulties in the normal wound healing process. Therefore, maggot debridement therapy (MDT) has not generally been recommended for CLI patients. We evaluated the effectiveness of wound bed preparation by MDT in CLI patients who had undergone mid-foot amputation.

METHODS

Patients who underwent mid-foot amputation after angioplasty between April 2014 and October 2016 were retrospectively investigated by classifying them into an MDT group or a conventional treatment group. The primary outcome was defined as achievement of wound healing. Secondary outcomes were the proportions of amputation-free survival (AFS) and successful ambulatory improvement. Propensity scores were used to evaluate treatment outcomes based on five factors: ankle-brachial index, skin perfusion pressure of the foot, nutritional status, experience with dialysis and age.

RESULTS

A total of 39 patients (39 legs) were included, seven within the MDT group and 32 in the conventional treatment group. Clinical backgrounds of the two groups showed no significant differences except for higher albumin levels for the MDT group (3.5±0.4g/dl; p=0.014). The wound healing proportion was significantly higher in the MDT group (86%) than in the control group (38%) (p=0.035). At 6 months after amputation, no significant differences were found between the two groups for AFS (71% versus 47%; p=0.41) or ambulatory capability (43% versus 28%; p=0.65). This result was also similar to the propensity score adjustment analysis.

CONCLUSIONS

The efficacy of MDT with favourable wound bed preparation was shown in our CLI patients based on effective debridement and granulation formation by maggots, avoiding the loss of their heels. Wound-healing rates after MDT were higher for patients than for those receiving conventional treatment. MDT is considered a valid adjuvant treatment strategy for patients with CLI after revascularisation treatment is conducted. More favourable wound bed preparation and successful graft take were achieved in the MDT group, suggesting the effectiveness of MDT for wound healing in CLI patients.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

MicroRNA‑93 regulates angiogenesis in peripheral arterial disease by targeting CDKN1A

MicroRNAs (miRNAs) are considered to be critical mediators of gene expression with respect to tumor progression, although their role in ischemia-induced angiogenesis is poorly characterized, including in peripheral arterial disease (PAD). Furthermore, the underlying mechanism of action of specific miRNAs in PAD remains unknown. Reverse transcription-quantitative polymerase chain reaction analysis revealed that microRNA-93 (miR-93) was significantly upregulated in patients with PAD and in the EA.hy926 endothelial cells in response to hypoxia. Additionally, miRNA (miR)-93 promoted angiogenesis by enhancing proliferation, migration and tube formation. Cyclin dependent kinase inhibitor 1A (CDKN1A), verified as a potential target gene of miR-93, was inhibited by overexpressed miR-93 at the protein and mRNA expression levels. Furthermore, a hind-limb ischemia model served to evaluate the role of miR-93 in angiogenesis in vivo, and the results demonstrated that miR-93 overexpression enhanced capillary density and perfusion recovery from hind-limb ischemia. Taken together, miR-93 was indicated to be a promising target for pharmacological regulation to promote angiogenesis, and the miR-93/CDKN1A pathway may function as a novel therapeutic approach in PAD.

The Majority of Patients Have Diagnostic Evaluation Prior to Major Lower Extremity Amputation

BACKGROUND

Critical limb ischemia (CLI) patients who do not undergo revascularization are at great risk for major lower extremity (LE) amputation. It has been reported that less than half (49%) of a reference Medicare amputation population had any diagnostic vascular evaluation prior to a major LE amputation. We were surprised by these data so we reviewed the preoperative evaluation in all patients who had a major LE amputation. We propose that significantly more patients will have a vascular evaluation prior to major LE amputation at a tertiary care referral center when a vascular surgeon does the amputation.

METHODS

A retrospective analysis of major LE amputations was performed. Patient demographics, comorbidities, type of amputation, reason for amputation, Rutherford classification, and type of preoperative vascular examination were evaluated.

RESULTS

Over 4 years, 281 patients required major LE amputation. Above-knee amputation was performed in 39.1% of patients, whereas below-knee amputation was performed in 60.9%. Amputation was performed due to CLI in 92.9% of patients, whereas 7.1% of amputations were performed due to diabetes or other reasons. Preoperative vascular evaluation was performed in 100% of patients undergoing major LE amputation. Vascular surgeon pulse examination was most common (99.3%) followed by pulse volume recordings/ankle-brachial index (78.8%), angiography (54.8%), computed tomography angiography (29.3%), duplex ultrasonography (41.3%), and magnetic resonance angiography (0.4%). Amputations most commonly occurred due to Rutherford classification VI (63.3%) with 97.2% of patients having Rutherford IV-VI classification.

CONCLUSIONS

Preoperative vascular evaluation prior to major LE amputation is achievable in the majority of patients, reported here in 100% of patients undergoing a major LE amputation. This allows us to evaluate the patient for revascularization options prior to amputation for possible limb salvage.

Preoperative beta blockade is associated with increased rates of 30-day major adverse cardiac events in critical limb ischemia patients undergoing infrainguinal revascularization

OBJECTIVE

The association between beta blockers and cardiovascular or limb-related outcomes after revascularization for critical limb ischemia (CLI) remains unclear. The objective of this study was to assess the impact of preoperative beta blockade on 30-day major adverse cardiac events (MACEs) and major adverse limb events (MALEs) in patients undergoing infrainguinal revascularization for CLI. We hypothesized that rates of MALEs and MACEs will be higher in patients not receiving preoperative beta blockade.

METHODS

The National Surgical Quality Improvement Program vascular targeted file for 2011 to 2014 identified patients receiving beta blockade and undergoing infrainguinal endovascular intervention and open bypass for CLI. Primary outcomes including 30-day MACE (stroke, myocardial infarction [MI], or death) and MALE (untreated loss of patency, reintervention, or amputation) were compared between patients taking and not taking preoperative beta blockers. Multivariate logistic regression identified independent predictors of MACEs and MALEs.

RESULTS

A total of 11,785 revascularizations were performed for CLI during the study period (7408 bypasses vs 4377 endovascular interventions). Preoperative beta blockers were used by 7365 patients, including 4541 (61.7%) in the open bypass cohort and 2824 (64.5%) in the endovascular group (P < .01). MACEs and MI were significantly higher in patients with preoperative beta blockers (MACEs, 5.8% vs 3.4% [P < .0001]; MI, 3.1% vs 1.8% [P < .0001]). After controlling for cardiac risk factors, beta blockers independently predicted MACEs (odds ratio [OR], 1.27; P = .03) and MI (OR, 1.36; P = .03) but not stroke (OR, 1.17; P = .58) or 30-day mortality (OR, 1.22; P = .19). Beta-blocker use did not have an effect on MALEs (OR, 0.99; P = .88).

CONCLUSIONS

In patients with CLI, preoperative beta blockade was an independent predictor of 30-day MI and MACEs after controlling for other cardiovascular risk factors. Beta blockers did not have an impact on short-term limb-related outcomes. The association between beta blockade and revascularization for CLI deserves further investigation.

Hyperbaric Oxygen Therapy Enhanced Circulating Levels of Endothelial Progenitor Cells and Angiogenesis Biomarkers, Blood Flow, in Ischemic Areas in Patients with Peripheral Arterial Occlusive Disease

Background: This study tested the hypothesis that hyperbaric oxygen (HBO) therapy enhanced the circulating levels of endothelial progenitor cells (EPCs), soluble angiogenesis factors, and blood flow in ischemic areas in patients with peripheral arterial occlusive disease (PAOD). Methods: In total, 57 consecutive patients with PAOD undergoing the HBO therapy (3 atmospheres (atm) for 2 h each time) were prospectively enrolled into the present study. Venous blood sampling was performed to assess the circulating levels of EPCs and soluble angiogenesis factors prior to and during five sessions of HBO therapy. Additionally, skin perfusion pressure (SPP), an indicator of blood flow in ischemic areas, was measured by moorVMS-PRES. Results: The results demonstrated that the circulating levels of EPCs (cluster of differentiation (CD)34⁺/CD133⁺/CD45^dim, CD31⁺/CD133⁺/CD45^dim, CD34⁺) and soluble angiogenesis factors—vascular endothelial growth factor/stromal cell-derived factor 1/hepatocyte growth factor/fibroblast growth factor (VEGF/SDF-1α/HGF/FGF) were significantly increased post-HBO therapy as compared to pre-HBO therapy (all p < 0.01). Additionally, Matrigel assay showed that the angiogenesis was significantly increased in post-HBO therapy as compared to prior to therapy (p < 0.001). Furthermore, SPP was significantly increased in the ischemic area (i.e., plantar foot and mean SPP of the ischemic foot) in post-HBO therapy as compared to pre-HBO therapy (all p < 0.01). Importantly, the HBO therapy did appear to result in complications, and all the patients were uneventfully discharged without amputation. Conclusions: HBO therapy augmented circulating levels of EPCs and angiogenesis factors, and improved the blood flow in the ischemic area.

Circulating MicroRNA-4739 May Be a Potential Biomarker of Critical Limb Ischemia in Patients with Diabetes

Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery disease, which is common but rarely diagnosed. Noninvasive biomarkers are urgently required to assist in the diagnosis of CLI. Accumulating evidence indicates that miRNAs play an important role in the development of various diseases. In this study, microarray profiling revealed 11 miRNAs with significantly altered expression in four T2DM patients with CLI compared with that in four sex- and age-matched T2DM patients without CLI. In independent cohorts, qRT-PCR validation confirmed the increased miRNA-4739 level in patients with CLI versus patients without CLI. miRNA-4739 levels increased with FPG and HbA1c (all P < 0.05). After adjusting for the risk factors, miRNA-4739 levels were found to be associated with an increased odds ratio (OR) of T2DM with CLI (OR =12.818, 95% confidence intervals (CI) 1.148 to 143.143, P = 0.038). ROC curve analysis revealed that the area under the curve (AUC) of miR-4739+confounding risk factors was 0.94 (95% CI 0.891 to 0.998, P < 0.001), which was higher than that of confounding risk factors (AUC 0.94 vs. 0.91, 95% CI -0.122 to 0.060, P > 0.05) and of miR-4739 (AUC 0.94 vs. 0.69, 95% CI -0.399 to -0.101, P < 0.001), respectively. We conclude that elevated plasma miRNA-4739 levels are independently associated with CLI in T2DM patients. miRNA-4739 is implicated as a novel diagnostic marker and a potential therapeutic target for CLI in diabetes.

Spinal Cord Stimulation Improves the Microvascular Perfusion Insufficiency Caused by Critical Limb Ischemia

OBJECTIVE

This retrospective case-controlled study intended to identify the benefits and efficacy of spinal cord stimulation (SCS) as a therapeutic strategy for patients with perfusion problems caused by critical limb ischemia (CLI). The outcomes of patients who received SCS were compared with those of patients who did not receive SCS.

METHODS

This study recruited 78 patients who were diagnosed with perfusion problems over the period of 2003-2011. Lower-limb Thallium-201 (²⁰¹ Tl) scintigraphy revealed that the patients exhibited a perfusion difference of <0.95. Thirty-seven of the recruited patients received SCS treatment and 41 did not receive SCS treatment. All patients received the same medication: 100 mg aspirin once a day and 500 mg paracetamol thrice a day. The outcomes of walking distance, walking time, and sleeping quality were measured and recorded. Pain intensities were evaluated using the visual analog scale (VAS) scoring system.

RESULTS

Prior to SCS implantation, patients in the SCS treatment group had worse walking distance (64.86 ± 40.80 vs. 613.70 ± 535.00, p < 0.001), walking time (2.65 ± 1.64 vs. 13.90 ± 11.91, p < 0.001), and sleep quality (1.70 ± 0.78 vs. 3.32 ± 1.17, p < 0.001) than patients in the non-SCS treatment group. At the one-year follow-up, however, patients in the SCS treatment group had significantly better walking distance (1595.00 ± 483.60, p < 0.001), walking time (48.92 ± 14.10, p < 0.001), and sleep quality (4.65 ± 0.92, p < 0.001) than patients in the non-SCS treatment group. Moreover, the VAS score of patients in the SCS treatment group improved one week (8.63 ± 0.54 vs. 4.48 ± 0.59, p < 0.001) and one year after SCS implantation (2.35 ± 0.62, p < 0.001). By contrast, at the one-year follow-up, the walking distance (277.60 ± 374.80, p = 0.002), walking time (9.44 ± 10.73, p = 0.078), sleep quality (2.20 ± 1.10, p < 0.001), and VAS score (7.98 ± 0.43, p = 0.020) of patients in the non-SCS treatment group worsened. Furthermore, lower-limb ²⁰¹ Tl scintigraphy revealed that microcirculation intensity increased in the lower extremities of patients in the SCS treatment group after SCS implantation relative to that before SCS implantation. Most importantly, 10 of the 41 patients in the non-SCS treatment group required the use of wheelchairs, whereas none of the patients in the SCS treatment group required the use of wheelchairs.

CONCLUSION

Treatment of CLI patient with SCS improved patient's walking ability, pain severity, and sleep quality. SCS should be considered as an effective treatment toward limb salvage in CLI.

Efficacy Outcomes of Endovascular Versus Surgical Revascularization in Critical Limb Ischemia: Results From a Prospective Cohort Study

Data on efficacy outcomes of endovascular versus surgical revascularization in patients with critical limb ischemia (CLI) in contemporary practice are limited. In this prospective cohort study, 353 consecutive patients with CLI were enrolled and allocated to endovascular (PTA [percutaneous transluminal angioplasty]), surgical (SURG), or no revascularization (No REVASC) after interdisciplinary consensus. Outcome measures were sustained primary clinical success (sPCS; survival without major amputation, repeated target extremity revascularization, and freedom from CLI), limb salvage, and amputation-free survival. Propensity-matched Kaplan-Meier analyses and stratified log-rank tests were performed. The PTA, SURG, and No REVASC groups consisted of 264, 62, and 27 patients, respectively. Compared to SURG patients, PTA patients were significantly older, had more risk factors, and more often had ischemic lesions. Propensity score-adjusted analyses showed no significant differences: sPCS was 51.3%/52.2%, limb salvage rate 91.5%/93.7%, and major amputation-free survival 90.5%/87.2% at 12 months for PTA and SURG, respectively. Amputation-free survival for the No REVASC group was 69% at 12 months. In conclusion, endovascular and surgical revascularization in CLI has comparable efficacy outcomes after 12 months. Contemporary overall outcome of patients with CLI is considerably better compared to earlier studies.

Current Status of Arterial Revascularization for the Treatment of Critical Limb Ischemia in Infrainguinal Atherosclerotic Disease

Critical limb ischemia (CLI) is the most severe form of peripheral arterial disease (PAD) that may result in limb loss and even death; thus, the fast and proper treatment should be employed as earlier as possible to prevent these catastrophic consequences. Arterial revascularization is almost always an indispensable treatment option for CLI. Although both endovascular and surgical revascularization procedures have an important role, nowadays, the hybrid revascularization as a combination of these revascularization procedures has also gained increasing popularity in the treatment of patients with CLI. This review provides an update on the arterial revascularization strategies for the treatment of CLI.

Siglec-5 is a novel marker of critical limb ischemia in patients with diabetes

Critical Limb Ischemia (CLI) is common but uncommonly diagnosed. Improved recognition and early diagnostic markers for CLI are needed. Therefore, the aim of our study was to identify plasma biomarkers of CLI in patients with type 2 diabetes mellitus (T2DM). In this study, antibody-coated glass slide arrays were used to determine the plasma levels of 274 human cytokines in four matched cases of diabetes with and without CLI. Potential biomarkers were confirmed in an independent cohort by ELISA. After adjusting for confounding risk factors, only plasma level of Siglec-5 remained significantly associated with an increased odds ratio (OR) for diabetes with CLI by binary logistic regression analysis. Receiver operating characteristic (ROC) curve analysis revealed the optimal cut-off points for Siglec-5 was 153.1 ng/ml. After entering Siglec-5, the AUC was 0.99, which was higher than that of confounding risk factors only (AUC = 0.97, P < 0.05). Siglec-5 was expressed in plaques, but not in healthy artery wall in T2DM patients. Elevated plasma Siglec-5 was independently associated with CLI in T2DM. Plasma Siglec-5 levels are implicated as an early diagnostic marker of CLI in T2DM patients and it may become a target for the prevention or treatment of CLI in diabetes.

Maggot debridement therapy for a patient with critical limb ischaemia and severe cardiac dysfunction: possibility of limb salvage

Ischaemic skin ulcer occurred on the foot of a 73-year-old man who had a history of fulminant myocarditis with severe cardiac dysfunction. We attempted wound bed preparation by maggot debridement therapy and salvaged his limb. It can be one of the adjuvant treatment strategies for critical limb ischaemia.

Non-compressible ABIs are associated with an increased risk of major amputation and major adverse cardiovascular events in patients with critical limb ischemia

Ankle-brachial indices (ABIs) are important for the assessment of disease burden among patients with peripheral artery disease. Although low values have been associated with adverse clinical outcomes, the association between non-compressible ABI (ncABI) and clinical outcome has not been evaluated among patients with critical limb ischemia (CLI). The present study sought to compare the clinical characteristics, angiographic findings and clinical outcomes of those with compressible (cABI) and ncABI among patients with CLI. Consecutive patients undergoing endovascular evaluation for CLI between 2006 and 2013 were included in a single center cohort. Major adverse cardiovascular events (MACE) were then compared between the two groups. Among 284 patients with CLI, 68 (24%) had ncABIs. These patients were more likely to have coronary artery disease ( p=0.003), diabetes ( p<0.001), end-stage renal disease ( p<0.001) and tissue loss ( p=0.01) when compared to patients with cABI. Rates of infrapopliteal disease were similar between the two groups ( p=0.10), though patients with ncABI had lower rates of iliac ( p=0.004) or femoropopliteal stenosis ( p=0.003). Infrapopliteal vessels had smaller diameters ( p=0.01) with longer lesions ( p=0.05) among patients with ncABIs. After 3 years of follow-up, ncABIs were associated with increased rates of mortality (HR 1.75, 95% CI: 1.12-2.78), MACE (HR 2.04, 95% CI: 1.35-3.03) and major amputation (HR 1.96, 95% CI: 1.11-3.45) when compared to patients with cABIs. In conclusion, ncABIs are associated with higher rates of mortality and adverse events among those undergoing endovascular therapy for CLI.

Ghrelin, MicroRNAs, and Critical Limb Ischemia: Hungering for a Novel Treatment Option

Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery disease. It is characterized by chronic pain at rest, skin ulcerations, and gangrene tissue loss. CLI is a highly morbid condition, resulting in a severely diminished quality of life and a significant risk of mortality. The primary goal of therapy for CLI is to restore blood flow to the affected limb, which is only possible by surgery, but is inadvisable in up to 50% of patients. This subset of patients who are not candidates for revascularisation are referred to as "no-option" patients and are the focus of investigation for novel therapeutic strategies. Angiogenesis, arteriogenesis and vasculogenesis are the processes whereby new blood vessel networks form from the pre-existing vasculature and primordial cells, respectively. In therapeutic angiogenesis, exogenous stimulants are administered to promote angiogenesis and augment limb perfusion, offering a potential treatment option for "no option" patients. However, to date, very few clinical trials of therapeutic angiogenesis in patients with CLI have reported clinically significant results, and it remains a major challenge. Ghrelin, a 28-amino acid peptide, is emerging as a potential novel therapeutic for CLI. In pre-clinical models, exogenous ghrelin has been shown to induce therapeutic angiogenesis, promote muscle regeneration, and reduce oxidative stress via the modulation of microRNAs (miRs). miRs are endogenous, small, non-coding ribonucleic acids of ~20-22 nucleotides which regulate gene expression at the post-transcriptional level by either translational inhibition or by messenger ribonucleic acid cleavage. This review focuses on the mounting evidence for the use of ghrelin as a novel therapeutic for CLI, and highlights the miRs which orchestrate these physiological events.

Predictors of Postoperative Outcome in Patients with Lower Limb Surgical Revascularization

Objective: In patients with critical limb ischemia who undergone revascularization procedures, the assessment of risk factors that may affect the postoperative outcome is of great importance. The main objective in this study is to assess the utility of two specific risk scores, the Finnvasc score and the modified Prevent III score.

Methods: We evaluated the applicability of these two risk scores in 150 patients who undergone an unilateral infrainguinal surgical revascularization procedure. The receiver operating characteristic curve analysis was used to estimate the predictive value of the scoring methods. A comparison between the risk scores, determine the areas under the curve. Medium-term prediction ability was analyzed for both scoring methods.

Results: The area under the curve of Finnvasc score for predicting amputation was 0.739 (95%CI:0.661-0.807) and of the modified PIII score 0.713 (95%CI:0.633-0.784); for restenosis we obtained 0.528 (95%CI:0.444-0.611), respectively 0.529 (95%CI:0.445-0.612) and for thrombosis 0.628 (95%CI:0.544-0.706) and 0.556 (95%CI:0.472-0.638), demonstrating that the Finnvasc score performs better in overall prediction. Heart failure is a strong independent predictor of amputation (p=0.0001, OR=26.90; 95%CI:5.81-124.2), restenosis (p=0.0003, OR=4.80; 95%CI:1.96-11.8) and mortality (p=0.01, OR=7.16; 95%CI:1.33-38.52).

Conclusions: The accuracy of the two risk scoring methods in predicting the medium-term outcome of patients undergoing surgical infrainguinal revascularization is acceptable. The Finnvasc score is easier to be applied to the characteristics of our patients.

AG490 suppresses EPO-mediated activation of JAK2-STAT but enhances blood flow recovery in rats with critical limb ischemia

Background

Erythropoietin (EPO) has been demonstrated to enhance recovery in ischemic organs through enhancing angiogenesis. In this study, we used an experimental critical limb ischemia (CLI) rat model to reveal the underlying mechanisms and directly examine the benefits of the anti-apoptotic capacity of EPO in the acute phase of limb ischemia and following blood flow recovery.

Methods

To determine the role of the JAK2/STAT pathway in EPO-enhanced recovery after CLI, male Sprague-Dawley rats (n = 8 for each group) were divided into group 1 (normal control), group 2 (CLI treated with normal saline), group 3 (CLI treated with EPO), group 4 (CLI treated with AG490, a JAK2 inhibitor), and group 5 (CLI treated with EPO and AG490). Animals were sacrificed either at day 1 or day 14 and biochemical and histopathological examination of ischemic quadriceps were conducted.

Results

At day 1, EPO administration reduced expression levels of apoptotic indices and activated the JAK2/STAT pathway; this activation was inhibited by additional AG490 treatment. Furthermore, the decrease in the size of the infarcted area, as well as activation of ERK1/2 and JNK showed similar regulatory trends with EPO or AG490 treatment. Of Interest, EPO and AG490 in combination showed a synergistic effect, increasing expression levels of antioxidants (GR, GPx, NQO-1) and decreasing transcriptional levels of pro-inflammatory factors (TNF-α, NF-kB). At day 14, laser Doppler analysis showed that the blood flow recovery was enhanced by EPO, AG490, or combined treatment.

Conclusion

Although inhibition of the JAK2/STAT pathways reduces the anti-apoptotic effects of EPO in the early phase of CLI, the benefits of AG490 in anti-inflammation and anti-oxidation still play a positive role in enhancing blood flow recovery after CLI.

Medical Therapy in Peripheral Artery Disease and Critical Limb Ischemia

OPINION STATEMENT

Peripheral artery disease (PAD) comprises atherosclerosis of the aorta and lower extremities. Many patients with PAD are asymptomatic, while others present with intermittent claudication (IC) or critical limb ischemia (CLI). Defined as rest pain or tissue loss that persists for >2 weeks, CLI represents the most severe clinical manifestation of PAD and is associated with an increased risk of limb loss and death. Patients with PAD, including those with CLI, are underdiagnosed and undertreated. In addition to smoking cessation, medical therapy with an antiplatelet agent and statin is recommended for all patients with PAD. Regular exercise has been shown to improve walking distance and quality of life in patients with symptomatic PAD and should be incorporated into each patient's treatment plan. In patients who have CLI and in those with persistent lifestyle-limiting claudication despite optimal medical therapy and an exercise program, revascularization is indicated for limb salvage and symptom relief, respectively. Consensus guidelines currently support an endovascular first approach to revascularization in the majority of cases. Surgical procedures provide an alternative to endovascular therapy in select cases.

Glypican-1 nanoliposomes for potentiating growth factor activity in therapeutic angiogenesis

Therapeutic angiogenesis is a highly appealing concept for treating tissues that become ischemic due to vascular disease. A major barrier to the clinical translation of angiogenic therapies is that the patients that are in the greatest need of these treatments often have long term disease states and co-morbidities, such as diabetes and obesity, that make them resistant to angiogenic stimuli. In this study, we identified that human patients with type 2 diabetes have reduced levels of glypican-1 in the blood vessels of their skin. The lack of this key co-receptor in the tissue may make the application of exogenous angiogenic growth factors or cell therapies ineffective. We created a novel therapeutic enhancer for growth factor activity consisting of glypican-1 delivered in a nanoliposomal carrier (a "glypisome"). Here, we demonstrate that glypisomes enhance FGF-2 mediated endothelial cell proliferation, migration and tube formation. In addition, glypisomes enhance FGF-2 trafficking by increasing both uptake and endosomal processing. We encapsulated FGF-2 or FGF-2 with glypisomes in alginate beads and used these to deliver localized growth factor therapy in a murine hind limb ischemia model. Co-delivery of glypisomes with FGF-2 markedly increased the recovery of perfusion and vessel formation in ischemic hind limbs of wild type and diabetic mice in comparison to mice treated with FGF-2 alone. Together, our findings support that glypisomes are effective means for enhancing growth factor activity and may improve the response to local angiogenic growth factor therapies for ischemia.

Endovascular reconstruction of popliteal and infrapopliteal arteries for limb salvage and wound healing in patients with critical limb ischemia - A retrospective analysis

Background

Advancement in endovascular techniques has led to rapid growth in endovascular revascularization, and it has emerged as a treatment for critical limb ischemia (CLI). Clinical effectiveness of revascularization has been frequently judged by vessel patency and limb salvage, but there is paucity of reports on outcomes of the wound. We present a retrospective analysis of immediate angiographic and 3-month clinical outcome of patients who underwent endovascular reconstruction of popliteal and infrapopliteal arteries for CLI.

Methods

All patients who underwent endovascular reconstruction of popliteal and/or infrapopliteal arteries for CLI and >70% stenosis on digital subtraction angiography between March 2010 and November 2014 and had a clinical follow-up of at least 3 months were selected for analysis.

Results

34 patients underwent endovascular reconstruction. 9 patients (26%) underwent only POBA and remaining 25 (74%) underwent additional stenting. 13 patients (38%) had multiple segmental revascularization. 24 patients (71%) had successful vessel recanalization. Linear flow to foot in at least one artery could be achieved in 20 patients (59%) post revascularization. Successful wound healing occurred in 11 (35%) patients with an additional 7 (21%) patients showing clinical improvement in their wounds. Limb salvage was achieved in 33 patients (97%) at 3-month follow-up.

Conclusion

Endovascular revascularization of popliteal and infrapopliteal arteries is a feasible, safe, and effective procedure for the treatment of CLI. Normal inflow and outflow with at least one of the three infrapopliteal vessels being patent is essential for adequate healing of chronic ulcers and prevention of major amputation.