No-option Critical Limb Ischemia Research Articles

Comparison of outcomes of percutaneous deep venous arterialization in multiple practice settings

ObjectiveWe compared the efficacy of percutaneous deep venous arterialization (pDVA) in patients with no-option chronic limb-threatening ischemia in the hospital vs in office-based laboratory (OBL) settings. MethodsA retrospective chart review was performed of all patients who underwent pDVA using off-the-shelf devices from January 2018 to March 2023 in a hospital and an OBL. We identified 73 eligible patients, 41 from a hospital setting (59% male; median age, 72 years; interquartile range, 18 years) and 32 from an OBL setting (59% males; 67 years; interquartile range, 16 years). All eligible patients were deemed to have no-option critical limb ischemia, had at least one patent proximal tibial artery available for the creation of an arteriovenous anastomosis, and were classified as having Rutherford classification IV or higher peripheral arterial disease. Patients were ineligible if classified as Rutherford classification III or lower, had active infection, did not have at least one appropriate venous target, and/or had rapidly progressing wounds requiring immediate major amputation. The primary outcome was major amputation-free survival (AFS). Secondary outcomes included technical success, limb salvage, survival, primary patency, reintervention rate, adverse events, and partial and complete wound healing. Outcomes were evaluated using Kaplan-Meier method, log-rank, and two-stage procedure tests. ResultsTechnical success was achieved in 70 patients (96%) with 1 hospital (2.4%) and 2 OBL (6.3%) patients lost to follow-up. Major AFS estimates at 6 months, 1 year, and 2 years were 51.4%, 40.4%, and 30.2% in the hospital group and 69.4%, 54.0%, and 49.5% in the OBL group, respectively. Partial wound healing estimates at 6 months, 1 year, and 2 years were 27.5%, 71.7%, and 81.2% in the hospital group and 62.7% at all time points in the OBL group. Complete wound healing estimates at 6 months, 1 year, and 2 years were 6.7%, 33.3%, and 33.3% in the hospital group and 5.3%, 37.7%, and 41.6% in the OBL group, respectively. There was no significant difference in major AFS (P = .13), limb salvage (P = .07), survival (P = .69), primary patency (P = .53), partial (P = .08), or complete wound healing (P = .79) between groups. Reintervention was performed in 8 hospital (20.5%) and 14 OBL (45.2%) patients. ConclusionspDVA is a feasible and safe procedure for no-option critical limb ischemia in the hospital and OBL setting without significant differences in outcomes at ≤2 years.

Short-Term Outcomes and Efficacy of Percutaneous Deep Vein Arterialization for No-Option Critical Limb Ischemia: A Systematic Review and Meta-Analysis.

Percutaneous deep vein arterialization (pDVA) is considered a treatment modality in patients with no-option critical limb ischemia. However, there is still a paucity of evidence regarding its safety and efficacy. MEDLINE (via PubMed), Embase and Web of Science databases as well as the CENTRAL registry up to the end of June 2023. This review adhered to the PRISMA guidelines (PROSPERO registration no. CRD42023445171). The risk of bias was assessed using the methodological index for non-randomized studies (MINORS). Primary endpoints included technical success, overall survival and limb salvage during the follow-up. Amputation-free survival at 30 days, 6 months and 1 year as well as complete wound healing, major adverse limb events and reintervention were investigated as secondary outcomes. Five observational studies, comprising 208 patients (142 Rutherford class 5/77 Rutherford class 6), were included. MINORS revealed a low risk of bias. The meta-analysis reached a pooled technical success rate of 96.2% (95% CI: 91.5-98.4), an overall survival of 82.8% (95% CI: 70.5-95.2) and a limb salvage rate of 77.2% (95% CI: 65.2-89.1) during the follow-up. The amputation-free survival at 30 days, 6 months and 1 year was 87.8%, 68.7% and 65.6%, respectively. Furthermore, pDVA resulted in a complete wound healing rate of 53.4% (95% CI: 30.3-76.5). The pooled reintervention rate was as high as 46.7% (37.1-56.3%). PDVA seems a feasible bail-out strategy for patients with no option for routine treatment of CLTI. However, due to the small number of studies, the strength of the evidence is low.

Wharton's jelly mesenchymal stem cells transplantation for critical limb ischemia in patients with type 2 diabetes mellitus: a preliminary report of phase I clinical trial.

Peripheral artery disease (PAD) affects more than 230 million people worldwide, with approximately 11% of patients presenting with advanced-stage PAD or critical limb ischemia (CLI). To avoid or delay amputation, particularly in no-option CLI patients with infeasible or ineffective revascularization, new treatment strategies such as regenerative therapies should be developed. Mesenchymal stem cells (MSCs) are the most popular cell source in regenerative therapies. They possess significant characteristics such as angiogenic, anti-inflammatory, and immunomodulatory activities, which encourage their application in different diseases. This phase I clinical trial reports the safety, feasibility, and probable efficacy of the intramuscular administration of allogeneic Wharton's jelly-derived MSCs (WJ-MSCs) in type 2 diabetes patients with CLI. Out of six screened patients with CLI, five patients were administered WJ-MSCs into the gastrocnemius, soleus, and the proximal part of the tibialis anterior muscles of the ischemic lower limb. The safety of WJ-MSCs injection was considered a primary outcome. Secondary endpoints included wound healing, the presence of pulse at the disease site, the absence of amputation, and improvement in visual analogue scale (VAS), pain-free walking time, and foot and ankle disability index (FADI). No patient experienced adverse events and foot or even toe amputation during the 6-month follow-up. Six months after the intervention, there were a significantly lower VAS score and significantly higher pain-free walking time and FADI score than the baseline, but no statistically significant difference was seen between other time points. In conclusion, allogeneic WJ-MSC transplantation in patients with CLI seems to be safe and effective.

Percutaneous Deep Venous Arterialization in Patients with No-Option Critical Limb Ischemia Performed in an Office-Based Laboratory Setting

PurposeTo evaluate the feasibility and safety of percutaneous deep venous arterialization (pDVA) performed in an office-based laboratory (OBL) for patients with no-option critical limb ischemia (CLI). Materials and MethodsA retrospective chart review was performed of all patients who underwent pDVA using commercially available devices from January 2018 to November 2021 in a single OBL. In total, 22 patients (10 males and 12 females; Rutherford 4, 5, and 6: n = 1, 8, and 13, respectively) were identified with a median follow-up of 140 days. Amputation-free survival, wound healing, pDVA patency, and overall survival were evaluated at 30 days, 6 months, and throughout the remaining follow-up period. ResultsAll patients had undergone failed previous attempts at endovascular arterial reconstruction. At 6 months after procedure, 6.4% of arteriovenous conduits remained patent; 83.3% (10/12) of patients experienced complete or partial wound healing. In addition, 78.6% of patients avoided an above-ankle amputation, and overall survival was 83.6%. Nine patients underwent endovascular reinterventions at 6 months. One mild adverse event and 4 moderate adverse events occurred after procedure, and 1 cardiac death occurred 5 days after procedure. ConclusionspDVA is safe and feasible in the OBL for patients with no-option CLI. Many patients avoided an above-ankle amputation during the study period despite low overall pDVA patency.

Evaluation of the lower extremity blood supply in no-option critical limb ischemia patients with stem cell transplantation by time maximum intensity projection CT perfusion: A single-centre prospective study.

Cell therapy has had satisfactory safety and efficacy outcomes for no-option critical limb ischaemia (NO-CLI) patients. In the current study, we aimed to compare the image quality of ischaemic lower limb blood vessels shown on volumetric CT-based time maximum intensity projection CT perfusion (t-MIP CTP) versus single-phase CTA (sCTA). We also tried to quantify the blood flow of the ischaemic lower extremity based on the t-MIP technique, not only to precisely show the dynamic change in blood flow from before to after cell therapy but also to detect any relationship between this change and patient prognosis. A total of 31 patients with thromboangiitis obliterans (TAO)-induced NO-CLI who had been referred from the department of vascular surgery to undergo autologous stem cell transplantation into a single limb from January 2020 to March 2021 were prospectively enrolled in this study. Preoperative sCTA or t-MIP CTP and postoperative 1-month t-MIP CTP were performed in all patients. Clinical outcomes, including the 1-month ankle-brachial index (ABI) and 3-month CLI status, were also analysed. Image quality, including objective scores (attenuation, signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]), subjective scores and collateral scores, was compared between preoperative sCTA and t-MIP CTP. Vascular volume was calculated as the total volume (mL) of lower limb arteries within the scanning range. All images and calculations were performed by 2 separate radiologists. Receiver operating characteristic curves were drawn to reveal the sensitivity and specificity of vascular volume and ABI in predicting prognosis. Both sCTA and t-MIP CTP images exhibited good quality for diagnosis. t-MIP CTP images showed significantly higher attenuation, SNR and CNR in all arterial segments (popliteal artery, anterior tibial artery, posterior tibial artery and peroneal artery). In subjective and collateral score evaluations, t-MIP CTP images were also significantly better than sCTA images (both p < .05). At 1 month after transplantation, both vascular volume and ABI showed significant improvement (both p < .01). At 3months after transplantation, 38.71% of patients (12/31) achieved CLI relief (Rutherford class < 4). Through the receiver operating characteristic (ROC) curve, the 1-month vascular volume increase ratio showed better ability to predict the 3-month prognosis (radiologist 1: AUC, 0.757; sensitivity, 0.750; specificity, 0.840; radiologist 2: AUC, 0.803; sensitivity, 0.500; specificity, 1.000) than the 1-month ABI increase ratio (AUC, 0.607; sensitivity, 0.230; specificity, 0.820) or 1-month ABI (AUC, 0.410; sensitivity, 0.080; specificity, 0.580). t-MIP CTP showed significantly higher-quality images of ischaemic limb vascularity than sCTA. t-MIP CTP can reveal the anatomical information of collaterals more accurately, which is of great importance for NO-CLI patients undergoing cell transplantation. The 1-month vascular volume increase ratio can predict the 3-month prognosis more precisely on this basis.

‘No-Option Chronic Limb-Threatening Ischaemia: What Can We Do To Save Limb?

The aim of this study is to describe the characteristics, the management and the outcome of a series of patients with no-option critical limb ischemia (CLI) treated with a conservative multidisciplinary combined approach including best wound care, NPWT and dermal substitutes. The primary end was limb salvage and 1-year amputation-free survival. The secondary end was mortality and healing time of lesion. Between January 2016 and January 2021, 76 patients with no options CLI were admitted. In 14 patients, there was a failure in distal revascularization with a persistent CLI after the procedure. In 58 patients, revascularization was not feasible. Despite the persistent CLI, a group of patients of this cohort obtained no progression of CLI, complete wound healing treated with surgical debridement or distal amputation and application of NPWT in association with dermal substitute .Any superimposed infection was treated with antimicrobials. Pain was controlled with analgesics. Overall limb was saved in 72 % of the cases. A 1-year survival was 84%.Use of NPWT, dermal substitutes combined with a conservative foot surgery with an approach with minor amputation in patients with no-option CLI may save patient limb and life

Duplex and Angiographic-Assisted Evaluation of Outcomes of Endovascular Embolization after Surgical Deep Vein Arterialization for the Treatment No-Option Critical Limb Ischemia Patients.

To report early and mid-term outcomes of the arterialization of the deep venous system in no-option critical limb-threatening ischemia (CLTI) using duplex ultrasound and angiographic evaluation to improve limb perfusion. A single-center prospective study of patients with no-option CLTI treated with hybrid surgical arterialization of the deep venous circulation and staged endovascular embolization of the venous collateral. Embolization was performed using a controlled-release spiral, within two weeks after bypass surgery. Patients were assessed for clinical status, wound healing, median transcutaneous partial pressure of O2 (TcPO2), and post-operative duplex ultrasound evaluating peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) to assess foot perfusion and bypass features. Primary endpoint analysis was primary technical success, limb salvage, patency rates, and clinical improvement. Secondary endpoints were 30-day and long-term mortality, major cardiovascular events (MACE), including myocardial infarction or stroke, and serious adverse events (SAE). Five patients with no-option CLTI were treated at our center using the hybrid deep vein arterialization technique. Clinical stage was grade 3 in one patient and grade 4 in the remaining four. Mean age was 65.8 years (range 49-76 years), and two patients were affected by Buerger's disease. Primary technical success was achieved in all patients, and all the bypasses were patent at the angiographic examination. At 30-day and at average follow-up of 9.8 months (range 2-24 months), mortality, major cardiovascular events (MACE), and serious adverse events (SAE) were not reported, with a primary patency and limb salvage rates of 100%. Three patients required minor amputation. Clinical improvement was demonstrated in all patients with granulation, resolution of rest pain, or both. Median TcPO2 values rose from 10 mm Hg (range 4-25) before the procedure to 35 (range 31-57) after surgery, and to 59 mm Hg (range 50-76) after the staged endovascular procedure. In our initial experience, the arterialization of the deep venous circulation, with subsequent selective embolization of the venous escape routes from the foot, seems a feasible and effective solution for limb salvage in patients with no-option CLTI and those in the advanced wound, ischemia, and foot infection (WIfI) clinical stage.

Marrow changes and reduced proliferative capacity of mesenchymal stromal cells from patients with “no-option” critical limb ischemia; observations on feasibility of the autologous approach from a clinical trial

Background aimsApproximately 1 in 3 patients with critical limb ischemia (CLI) are not suitable for surgical or endovascular revascularization. Those “no-option” patients are at high risk of amputation and death. Autologous bone marrow mesenchymal stromal cells (MSCs) may provide a limb salvage option. In this study, bone marrow characteristics and expansion potentials of CLI-derived MSCs produced during a phase 1b clinical trial were compared with young healthy donor MSCs to determine the feasibility of an autologous approach. Cells were produced under Good Manufacturing Practice conditions and underwent appropriate release testing. MethodsFive bone marrow aspirates derived from patients with CLI were compared with six young healthy donor marrows in terms of number of colony-forming units–fibroblast (CFUF) and mononuclear cells. The mean population doubling times and final cell yields were used to evaluate expansion potential. The effect of increasing the volume of marrow on the CFUF count and final cell yield was evaluated by comparing 5 CLI-derived MSCs batches produced from a targeted 30 mL of marrow aspirate to five batches produced from a targeted 100 mL of marrow. ResultsCLI-derived marrow aspirate showed significantly lower numbers of mononuclear cells with no difference in the number of CFUFs when compared with healthy donors’ marrow aspirate. CLI-derived MSCs showed a significantly longer population doubling time and reduced final cell yield compared with young healthy donors' MSCs. The poor growth kinetics of CLI MSCs were not mitigated by increasing the bone marrow aspirate from 30 to 100 mL. ConclusionsIn addition to the previously reported karyotype abnormalities in MSCs isolated from patients with CLI, but not in cells from healthy donors, the feasibility of autologous transplantation of bone marrow MSCs for patients with no-option CLI is further limited by the increased expansion time and the reduced cell yield.

Abstract No. 115 Early experience with deep venous arterialization in patients with no-option critical limb ischemia in the office-based lab setting

Abstract No. 115 Early experience with deep venous arterialization in patients with no-option critical limb ischemia in the office-based lab setting

Autologous Immune Cell-Based Regenerative Therapies to Treat Vasculogenic Erectile Dysfunction: Is the Immuno-Centric Revolution Ready for the Prime Time?

About 35% of patients affected by erectile dysfunction (ED) do not respond to oral phosphodiesterase-5 inhibitors (PDE5i) and more severe vasculogenic refractory ED affects diabetic patients. Innovative approaches, such as regenerative therapies, including stem cell therapy (SCT) and platelet-rich plasma (PRP), are currently under investigation. Recent data point out that the regenerative capacity of stem cells is strongly influenced by local immune responses, with macrophages playing a pivotal role in the injury response and as a coordinator of tissue regeneration, suggesting that control of the immune response could be an appealing approach in regenerative medicine. A new generation of autologous cell therapy based on immune cells instead of stem cells, which could change regenerative medicine for good, is discussed. Increasing safety and efficacy data are coming from clinical trials using peripheral blood mononuclear cells to treat no-option critical limb ischemia and diabetic foot. In this review, ongoing phase 1/phase 2 stem cell clinical trials are discussed. In addition, we examine the mechanism of action and rationale, as well as propose a new generation of regenerative therapies, evolving from typical stem cell or growth factor to immune cell-based medicine, based on autologous peripheral blood mononuclear cells (PBMNC) concentrates for the treatment of ED.

Cellular therapies in no-option critical limb ischemia: present status and future directions.

Critical limb ischemia - an advanced stage of lower extremity arterial disease with presence of rest pain and/or ischemic ulcers - remains an important cause of major amputations and disability in developed societies. Novel treatment strategies are urgently needed to prevent (or delay) amputations in particular for patients in whom effective revascularization is no longer feasible for anatomic and/or technical reasons (no-option critical limb ischemia - N-O CLI). Cellular therapies have been gaining the growing attention of researchers and clinicians in the last two decades. Several cell types have been used in pre-clinical and clinical studies, and a number of mechanisms have been proposed to contribute to vascular reparation and regeneration in N-O CLI. Although early trials suggested clinical improvement with use of cell-based therapies in N-O CLI, meta-analyses that included randomized controlled trials have not provided definitive conclusions. Fundamental limitations have involved poorly defined cell lines/populations, limited numbers of study participants and limited follow-up periods, and enrolling patients "too sick to benefit" (such as those in Rutherford class 6). Recent advances include standardized "unlimited" sources of therapeutic cells and better understanding of mechanisms that may contribute to vascular reparation and regeneration. Furthermore, based on recent pre-clinical and clinical studies, cell-free preparations (such as microvesicle-based) are being increasingly developed along with advanced therapy medical products consisting of engineered cells and pro-angiogenic factors.

Combined intra-arterial and intra-muscular transfer of Wharton's jelly mesenchymal stem/stromal cells in no-option critical limb ischemia - CIRCULATE N-O CLI Pilot Study.

Despite progress in pharmacologic and revascularization therapies, no-option critical limb ischemia poses a major clinical and societal problem. Prior cell-based strategies involved mainly autologous (limited) cell sources. To evaluate the safety and feasibility of a novel ischemic tissue reparation/regeneration strategy using Wharton's jelly mesenchymal stem/stromal cells (WJMSCs) as an "unlimited" cell source in N-O CLI (first-in-man study, FIM). Enrollment criteria included Rutherford-4 to Rutherford-6 in absence of anatomic/technical feasibility for revascularization and adequate inflow via the common femoral artery with patency of at least one below-the-knee artery. 30 × 106 WJMSCs were administered intra-arterially and intra-muscularly (50%/50%) over 3-6-week intervals (3-6 administrations). Safety, feasibility and potential signals of efficacy were assessed at 12 and 48 months. Five patients (age 61-71, 60% male, Rutherford-6 20%, Rutherford-5 60%, Rutherford-4 20%) were enrolled. WJMSCs were administered per protocol in absence of administration technique-related adverse events. Hyperemia, lasting 12-24 h, occurred in 4/5 subjects. Transient edema and pain (reactive to paracetamol) occurred in 3 (60%) patients. Amputation-free survival was 80% after 12 and 48 months. In those who avoided amputation, ischemic ulcerations healed and Rutherford stage improved. 4/5 patients were free of resting pain after 3-6 doses. This FIM study demonstrated the safety and feasibility of WJMSCs use in patients with N-O CLI and suggested treatment efficacy with ≥ 3 doses. Our findings provide a basis for a randomized, double-blind clinical trial to assess the efficacy of WJMSC-based therapeutic strategy in N-O CLI patients.

Autologous Peripheral Blood Mononuclear Cells for Limb Salvage in Diabetic Foot Patients with No-Option Critical Limb Ischemia.

Peripheral blood mononuclear cells (PBMNCs) are reported to prevent major amputation and healing in no-option critical limb ischemia (NO-CLI). The aim of this study is to evaluate PBMNC treatment in comparison to standard treatment in NO-CLI patients with diabetic foot ulcers (DFUs). The study included 76 NO-CLI patients admitted to our centers because of CLI with DFUs. All patients were treated with the same standard care (control group), but 38 patients were also treated with autologous PBMNC implants. Major amputations, overall mortality, and number of healed patients were evaluated as the primary endpoint. Only 4 out 38 amputations (10.5%) were observed in the PBMNC group, while 15 out of 38 amputations (39.5%) were recorded in the control group (p = 0.0037). The Kaplan–Meier curves and the log-rank test results showed a significantly lower amputation rate in the PBMNCs group vs. the control group (p = 0.000). At two years follow-up, nearly 80% of the PBMNCs group was still alive vs. only 20% of the control group (p = 0.000). In the PBMNC group, 33 patients healed (86.6%) while only one patient healed in the control group (p = 0.000). PBMNCs showed a positive clinical outcome at two years follow-up in patients with DFUs and NO-CLI, significantly reducing the amputation rate and improving survival and wound healing. According to our study results, intramuscular and peri-lesional injection of autologous PBMNCs could prevent amputations in NO-CLI diabetic patients.

Main Factors Predicting Nonresponders to Autologous Cell Therapy for Critical Limb Ischemia in Patients With Diabetic Foot.

Autologous cell therapy (ACT) is a new treatment for patients with no-option critical limb ischemia (NO-CLI). We evaluated the factors involved in the nonresponse to ACT in patients with CLI and diabetic foot. Diabetic patients (n = 72) with NO-CLI treated using ACT in our foot clinic over a period of 8 years were divided into responders (n = 57) and nonresponders (n = 15). Nonresponder was defined as an insufficient increase in transcutaneous oxygen pressure by <5 mm Hg, 3 months after ACT. Patient demographics, diabetes duration and treatment, and comorbidities as well as a cellular response to ACT, limb-related factors, and the presence of inherited thrombotic disorders were compared between the 2 groups. The main independent predictors for an impaired response to ACT were heterozygote Leiden mutation (OR 10.5; 95% CI, 1.72-4) and homozygote methylenetetrahydrofolate reductase (MTHFR 677) mutation (OR 3.36; 95% CI, 1.0-14.3) in stepwise logistic regression. Univariate analysis showed that lower mean protein C levels (P = .041) were present in nonresponders compared with responders. In conclusion, the significant predictors of an impaired response to ACT in diabetic patients with NO-CLI were inherited thrombotic disorders.

Three-year outcomes of peripheral blood mononuclear cells vs purified CD34+ cells in the treatment of angiitis-induced no-option critical limb ischemia and a cost-effectiveness assessment: A randomized single-blinded noninferiority trial.

For patients with angiitis‐induced critical limb ischemia (AICLI), cell transplantation, such as purified CD34+ cells (PCCs) and peripheral blood mononuclear cells (PBMNCs), is gradually being used as a promising treatment. This was the first randomized single‐blinded noninferiority trial (number: NCT 02089828) specifically designed to evaluate the therapeutic efficacies of the transplantation of PCCs vs those of PBMNCs for the treatment of AICLI. We aimed to compare the mid‐term safety and efficacy between the two groups and determine their respective advantages. From April 2014 to September 2019, 50 patients with AICLI were equally allocated to the two groups, except for 1 lost patient, 1 amputee, and 1 patient who died of heart disease. The other 47 patients completed the 36‐month follow‐up. The endpoints were as follows: major amputation‐free survival and total amputation‐free survival at 6 months, which were 96.0% and 84.0% in the PBMNCs group and 96.0% and 72.0% in the PCCs group, respectively. These rates remained stable at 12, 24, and 36 months. The PCCs group had a significant higher probability of rest pain relief than the PBMNCs group, whereas earlier significant improvements in the Rutherford classification were observed in the PBMNCs group. Accordingly, PCCs would be preferred for patients with significant pain, whereas PBMNCs may be a good option for patients with two or more critically ischemic limbs. Concerning cost‐effectiveness, PCCs are not more cost‐effective than PBMNCs. These outcomes require verification from long‐term trials involving larger numbers of patients.

Current Status of Cell-Based Therapy in Patients with Critical Limb Ischemia.

(1) Background: The treatment of peripheral arterial disease (PAD) is focused on improving perfusion and oxygenation in the affected limb. Standard revascularization methods include bypass surgery, endovascular interventional procedures, or hybrid revascularization. Cell-based therapy can be an alternative strategy for patients with no-option critical limb ischemia who are not eligible for endovascular or surgical procedures. (2) Aims: The aim of this narrative review was to provide an up-to-date critical overview of the knowledge and evidence-based medicine data on the position of cell therapy in the treatment of PAD. The current evidence on the cell-based therapy is summarized and future perspectives outlined, emphasizing the potential of exosomal cell-free approaches in patients with critical limb ischemia. (3) Methods: Cochrane and PubMed databases were searched for keywords “critical limb ischemia and cell therapy”. In total, 589 papers were identified, 11 of which were reviews and 11 were meta-analyses. These were used as the primary source of information, using cross-referencing for identification of additional papers. (4) Results: Meta-analyses focusing on cell therapy in PAD treatment confirm significantly greater odds of limb salvage in the first year after the cell therapy administration. Reported odds ratio estimates of preventing amputation being mostly in the region 1.6–3, although with a prolonged observation period, it seems that the odds ratio can grow even further. The odds of wound healing were at least two times higher when compared with the standard conservative therapy. Secondary endpoints of the available meta-analyses are also included in this review. Improvement of perfusion and oxygenation parameters in the affected limb, pain regression, and claudication interval prolongation are discussed. (5) Conclusions: The available evidence-based medicine data show that this technique is safe, associated with minimum complications or adverse events, and effective.

Characteristics and Outcome for Persons with Diabetic Foot Ulcer and No-Option Critical Limb Ischemia.

The study aimed to evaluate clinical and vascular characteristics, as well as outcomes, for diabetic persons with foot ulceration and no-option critical limb ischemia (CLI). The study group included a sample of patients admitted to our diabetic foot unit because of a new diabetic foot ulcer and CLI. All subjects were managed using a limb salvage protocol which includes lower-limb revascularization. According to whether or not the revascularization procedure was a success, patients were respectively divided into two groups: successfully treated CLI patients (ST-CLI) and no-option CLI patients (NO-CLI). Failed revascularization was considered in the case of technical recanalization failure of occluded vessels (inability to overcome the obstruction) and/or absence of arterial flow to the foot. Limb salvage, major amputation, and death after 1 year of follow-up were evaluated and compared between the two groups. Overall, 239 patients were included, 74.9% belonging to ST-CLI and 25.1% to NO-CLI. NO-CLI patients reported more cases of ischemic heart disease (80 vs. 62.1, p = 0.008), heart failure (63.3 vs. 32.4%, p < 0.0001), and end-stage renal disease (ESRD) (60 vs. 25.7%) than ST-CLI patients. In addition, more vessels were affected in the NO-CLI group (5.2 ± 1.6 vs. 4 ± 1.5, p < 0.0001), and there was more involvement of tibio-peroneal trunk (50 vs. 30.2%, p = 0.006), anterior tibial (93.3 vs. 82.7, p = 0.03), posterior tibial (93.3 vs. 73.7%, p = 0.0005), peroneal (70 vs. 48%, p = 0.002), and below-the-ankle arteries (73.3 vs. 39.1%, p < 0.0001) than ST-CLI. The 1 year outcomes for the whole population were 69.9% limb salvage, 10.9% major amputation, and 19.2% death. The outcomes for NO-CLI and ST-CLI were, respectively, as follows: limb salvage (13.8 vs. 73.4%, p < 0.0001), amputation (30 vs. 4.5%, p = 0.0001), and mortality (50 vs. 8.9%, p < 0.0001). NO-CLI patients showed a more severe pattern of peripheral arterial disease (PAD) with distal arterial lesions and worse outcomes than ST-CLI.

Autologous peripheral blood-derived stem cells transplantation for treatment of no-option angiitis-induced critical limb ischemia: 10-year management experience

BackgroundPrevious studies have demonstrated that no-option angiitis-induced critical limb ischemia (NO-AICLI) could be significantly improved by transplantation of peripheral blood-derived stem cells (PBDSCs). Additionally, a randomized controlled trial (RCT) recently conducted by us suggested that peripheral blood-derived purified CD34+ cells (PCCs) were not inferior to non-purified peripheral blood mononuclear cells (PBMNCs) at limb salvage in treatment of NO-AICLI. However, most of these clinical trials whether RCT or single-arm studies were characterized with a small sample size and absence of long-term outcomes.MethodsTo analyze long-term clinical outcomes of PBDSCs transplantation for NO-AICLI, we reviewed clinical data of patients with NO-AICLI receiving PBDSCs transplantation at our center during the past decade. Meanwhile, we first compared the long-term safety and efficacy of intramuscular transplantation of PCCs versus PBMNCs in a sizable number of patients with NO-AICLI.ResultsFrom May 2009 to December 2019, a total of 160 patients with NO-AICLI patients were treated by PBDSCs transplantation (82 with PCCs, 78 with PBMNCs) at our center. Baseline characteristics between two groups were similar. Up to June 2020, the mean follow-up period was 46.6 ± 35.3 months. No critical adverse events were observed in either group. There was one death during the follow-up period. A total of eight major amputations occurred. The cumulative major amputation-free survival (MAFS) rate at 5 years after PBDSCs transplantation was 94.4%, without difference between two groups (P = .855). Wound healing, rest pain, pain-free walking time, ankle-brachial index, transcutaneous oxygen pressure, and quality of life (QoL) also significantly improved after PBDSCs transplantation.ConclusionsAutologous PBDSCs intramuscular transplantation could significantly decrease the major amputation rates and improve the QoL in patients with NO-AICLI. Long-term observation of a large sample of patients confirmed that the clinical benefits of PBDSCs transplantation were durable, without difference between the PCCs and PBMNCs groups.

Peripheral Arterial Disease in Persons with Diabetic Foot Ulceration: a Current Comprehensive Overview.

In developed countries, the prevalence of persons with diabetes and peripheral arterial disease (PAD) is approximately 50%. The presence of PAD is associated with non-healing ulcers, major amputation, cardiovascular morbidity, and mortality. It is estimated that persons with diabetes, foot ulceration and PAD have 50% of 5-years mortality rate. Therefore, subjects with ischemic diabetic foot ulcers (DFUs) should be considered a special group of patients with specific clinical characteristics, general health status and prognosis. In persons with ischemic DFUs, an early diagnosis and treatment are mandatory to reduce the risk of worse outcomes such as major amputation. Revascularization of occluded lower extremity arteries is the main treatment to restore blood flow in the foot and promote wound healing. Nonetheless, there are several unmet needs in the management of diabetic subjects with PAD and foot ulceration as medical therapy, diagnostic criteria and indications for revascularization, revascularization strategy and technical approach as well as the management of no-option critical limb ischemia patients. It is a common opinion that there is an evolution of PAD features in diabetic persons, which seems to present a more aggressive pattern. This may be related to the frequent presence of concomitant comorbidities such as renal failure which could influence the characteristics of atherosclerotic plaques and their distribution. The aim of this review is to commence a complete overview and state of the art in the treatment of patients with diabetes, PAD, and foot ulceration and to describe the current challenges and future perspectives.

Design of a potentially registrational study of sakigake-designated GCSF-Mobilized autologous CD34 cell (CLBS12) Therapy of no-option critical limb ischemia including arteriosclerosis obliterans and Buerger's Disease

Background & Aim CLBS12 (autologous, mobilized peripheral blood derived selected CD34 cells) has previously been studied for the treatment of No-Option Critical Limb Ischemia (NOCLI) in Phase 1 and 2 studies in Japan and the United States. These studies demonstrated statistically significant improvement in key outcome measures including reduced Rutherford category, improved walking distance, reduction in pain, improvement in blood flow and tissue oxygenation, reduction in size and number of ulcers, and improved amputation-free survival. In one of the Japan studies, more than 80% of subjects treated with a single administration of CD34 cells became CLI-free and maintained this status through 4 years of observation. The promising results of these studies led to discussions with the PMDA regarding the design of a confirmatory study that, with a favorable outcome, could support registration of CLBS12 in Japan for NOCLI under the new regenerative medicine regulations. Methods, Results & Conclusion The study is a prospective, randomized clinical trial in subjects with arteriosclerosis obliterans (ASO; n=30) or Buerger's Disease (BD; n=5). All patients receive standard-of-care treatment (SOC). The study calls for randomization of 30 subjects with ASO to receive either CLBS12 or to continue with SOC alone. Additionally, 5 subjects with BD were to be allocated to a sub-study and receive CLBS12 while continuing SOC treatment. The primary endpoint for the study is ability to achieve a continuous CLI-free state. Other key measures include progression-free, amputation-free, and overall survival; Rutherford category; tissue oxygenation; blood flow; ulcer size, depth, and infection; pain; and quality-of-life. For preparation of CLBS12, subjects are mobilized with GCSF 5 µg/day for 5 days, then undergo apheresis to collect a mononuclear cell fraction. CD34 cells are separated using a magnetic separation method. CLBS12 is formulated as a cell suspension in proprietary media in a 10 mL volume for administration as a series of 20 intramuscular injections in one affected limb. The study was initiated in December 2017 and is expected to be completed in 2020. The BD sub-study has enrolled 6 subjects and half have achieved a continuous CLI-free state. Interim data from the trial will be presented.