Lower Extremity Ischemia Research Articles

Does Functional Status Predict Worse 30-D Outcomes in Endovascular Repair of Abdominal Aortic Aneurysms? A Propensity-Score Matched Study From ACS-NSQIP Targeted Database From 2012 to 2022

IntroductionIn patients undergoing endovascular aneurysm repair (EVAR), existing studies have identified an association between dependent functional status (DFS) and poorer outcomes after EVAR. However, noted limitations, especially the lack of differentiation between ruptured and nonruptured abdominal aortic aneurysm (AAA), potentially affect the extrapolation of these findings to specific patient groups. Thus, this study aimed to evaluate the association between functional status and 30-d outcomes after EVAR in ruptured and nonruptured AAA patients separately. MethodsPatients who underwent infrarenal EVAR were identified in the American College of Surgeons National Surgical Quality Improvement Program targeted database from 2012-2022. Patients with DFS and those with independent functional status (IFS) were stratified into the two study cohorts. In nonruptured AAA, a 1:1 propensity-score matching was used to address demographics, baseline characteristics, aneurysm diameter, distal extent of the aneurysm, anesthesia, and concomitant procedures between patients with DFS and IFS. The sample size for ruptured patients with AAA was too small for meaningful statistical analysis so only qualitative description was provided. Thirty-d postoperative mortality and morbidities of EVAR were assessed. ResultsFor nonruptured cases, there were 380 (2.55%) DFS and 14,545 (97.45%) patients with IFS, where 453 patients with IFS were matched to the DFS cohort. For ruptured AAA, there were 17 (6.39%) DFS and 249 (93.61%) IFS. After matching, nonruptured DFS and patients with IFS had similar 30-d mortality rates (2.37% vs 2.11%, P = 1.00). However, patients with DFS had a higher risk of bleeding requiring transfusion (18.42% vs 11.84%, P = 0.01) and longer length of stay (median 3.00 [Q1 1.00, Q3 6.00] vs median 2.00 [Q1 1.00, Q3 4.00] d, P < 0.01). All other outcomes, including major adverse cardiovascular events, cardiac complications, stroke, pulmonary complications, renal complications, sepsis, venous thromboembolism, wound complications, lower extremity ischemia, ischemic colitis, postoperative ruptured aneurysm, unplanned reoperation, 30-d readmission, were not different between patients with DFS and IFS. Qualitatively, ruptured patients with DFS had higher crude rates of 30-d mortality and morbidities compared to patients with IFS. ConclusionsContrary to previous literature, patients with DFS with nonruptured AAA undergoing EVAR were found to have largely comparable outcomes to patients with IFS, although extra attention should be paid to postoperative bleeding.

Preoperative clinical characteristics and risk assessment in Sun’s modified classification of Stanford type A acute aortic dissection

ObjectivesThis study aims to retrospectively analyze the clinical features of Stanford type A acute aortic dissection (TAAAD) based on Sun’s modified classification, and to investigate whether the Sun’s modified classification can be used to assess the risk of preoperative rupture.MethodsClinical data was collected between January 2018 and June 2019. Data included patient demographics, history of disease, type of dissection according to the Sun’s modified classification, time of onset, biochemical tests, and preoperative rupture.ResultsA total of 387 patients with TAAAD who met the inclusion criteria of Sun’s modified classification were included. There were more complex types, with 75, 151 and 140 patients in the type A1C, A2C and A3C groups, respectively. The age of the entire group of patients was 51.46 ± 12.65 years and 283 (73.1%) were male. The time from onset to the emergency room was 25.37 ± 30.78 h. There were a few cases of TAAAD combined with stroke, pericardial effusion, pleural effusion, and lower extremity and organ ischemia in the complex type group. The white blood cell count (WBC), neutrophil count (NEC) and blood amylase differed significantly between the groups. Three independent risk factors for preoperative rupture were identified: neutrophil count, blood potassium ion level, and platelet count. Binary logistic regression analysis showed that the Sun’s modified classification could not be used to assess the risk of preoperative rupture in TAAAD.ConclusionTAAAD was classified as the complex type in most patients. WBC, NEC and blood amylase were significantly different between the groups. NEC and serum potassium ion level were independent risk factors for preoperative rupture of TAAAD, while platelet count was its protective factor. More samples are needed to determine whether Sun’s modified classification can be used to evaluate the risk of preoperative rupture.

Operative Times and Outcomes of Complex Endovascular Repairs of Thoracoabdominal Aneurysms

IntroductionOwing to the significant morbidity and mortality of open thoracoabdominal aortic aneurysm surgery, complex endovascular repairs (eTAAA) have become increasingly common, but still carry substantial risk. These repairs require large bore access, with resultant pelvic and lower extremity ischemia. We therefore hypothesized that operative timing would be associated with outcomes, as efficient surgery would limit the ischemic time as well as anesthesia time. MethodsWe studied all eTAAA repairs (Crawford Types 1-3, 5) incorporating at least one branch vessel from 2014 to 2021 in the Vascular Quality Initiative, and categorized them into quartiles of total operating time. To account for variations in case complexity and intraoperative events, we performed a sub-analysis stratifying each surgeon by their median operating time. Multilevel logistic regression was employed to compare perioperative outcomes including mortality, thoracoabdominal life altering events (TALE:composite of perioperative death, stroke, permanent paralysis and/or dialysis), spinal cord ischemia (SCI), acute kidney injury (AKI), major adverse cardiac events (MACE), myocardial infarction, and dialysis. ResultsThere were 2,925 eTAAA repairs during the study period. Procedure times ranged from <204 minutes in the first quartile to >365 minutes in the fourth. Longer cases more commonly involved older patients who were more often female, and higher rates of prior stroke, and preoperative anemia. They involved larger, more extensive aneurysms, with higher rates of prior aortic surgery, and more commonly employed PMEGs or parallel grafting to incorporate more branch vessels. In addition, they were less often staged procedures, and used more spinal drains, femoral cutdowns, and upper extremity access. Operating time decreased as experience increased. In adjusted analyses, the odds of mortality and every morbidity studied increased stepwise with operating time, with 4 to 13-fold higher odds in the highest quartiles. Spinal cord ischemia had the strongest association with procedure times, with seven-fold higher odds (OR 7.2 [2.9-17.9], P<.001) of any SCI in the highest quartile compared to the lowest, and 13-fold higher odds of permanent SCI (OR 13.1 [3.9-44.7], P<.001). These results were consistent when surgeons were grouped into quartiles by their median operating times. Medium-term mortality was also higher in the upper quartile of operating time (HR 2.7 [1.4-5.1], P=.002). ConclusionLonger operating times for complex eTAAA repairs were associated with markedly higher rates of morbidity and mortality, especially spinal cord ischemia. These results emphasize the importance of expeditious repairs by experienced teams.

The application of cell products for the treatment of critical limb ischemia in patients with diabetes mellitus: a review of the literature

The number of patients with diabetes mellitus (DM) has been progressively increasing worldwide over the past decades, and many international organizations consider DM as a public health emergency of the 21st century.Critical limb ischemia (CLI) is the most severe stage of peripheral arterial disease (PAD) in DM and is characterized by a high risk of limb loss without revascularization. Traditional treatment tactics include open and endovascular revascularization surgical techniques. However, in patients not eligible for revascularization and in cases where performed surgical treatment performed has been ineffective, there are almost no therapeutic alternatives, often leading to amputations and death. As of today, one of the newest non-surgical treatment options is cell therapy. Among different cells, mesenchymal stromal cells (MSCs) are potentially one of the most prospective for use in this patient population.This article provides an overview of clinical trials using cell therapy in patients with CLI.To analyze publications, electronic databases PubMed, SCOPUS, ClinicalTrials, and ScienceDirect were searched to identify published data from clinical trials, research studies, and review articles on cell therapy for critical lower extremity ischemia. After the search, 489 results were received.As a result of systematic selection, 22 clinical trials were analyzed.According to the analyzed literature data, the use of cell products in this category of patients is effective and safe. Cell therapy can stimulate the formation of new vessels and enhances collateral circulation; it is also reported improved distal perfusion, increased pain-free walking distance, decreased amputation rates, and increased survival rates.Nevertheless, further study of the potential use of this category of drugs is needed.

Clinical Outcomes and Left Ventricular Functional Remodeling after Extracorporeal Membrane Oxygenation Assisted Percutaneous Coronary Intervention in Patients with Ischemic Cardiomyopathy: A Single-Center Retrospective Observational Study of 76 Cases.

Ischemic cardiomyopathy (ICM) is a common condition that leads to left ventricular (LV) functional remodeling and poor prognosis. Extracorporeal membrane oxygenation (ECMO) can provide temporary circulatory support and facilitate percutaneous coronary intervention (PCI) in patients with ICM and hemodynamic instability. However, the impact of ECMO-assisted PCI on LV functional remodeling and clinical outcomes in ICM patients is unclear. We retrospectively analyzed 76 patients with ICM who underwent ECMO-assisted PCI at our institution between January 2013 and December 2022. We assessed the changes in LV functional remodeling using echocardiography at baseline and 12 months after the procedure. We also evaluated the incidence of major adverse cardiac and cerebrovascular events (MACCEs) and ECMO-related complications during hospitalization and at one-year follow-up. The mean baseline left ventricular ejection fraction (LVEF) was 29.98 ± 2.65%. The rate of complete revascularization was 58%. The median duration of ECMO support was 38.99 hours. The most common ECMO-related complications were bleeding (8%) and lower extremity ischemia (5%). The one-year mortality rate was 30%. The overall freedom from MACCEs at 12 months was 59% (95% confidence interval (CI): 49-71%). LVEF increased significantly after the procedure from baseline to 6 months, yet decreased slightly at 12 months, although it was still higher than the baseline value. Wall motion score index (WMSI), end-diastolic volume index (EDVI), and end-systolic volume index (ESVI) decreased significantly from baseline to 12 months, indicating an improvement in LV function and a reduction in LV size. In a high-volume tertiary center with extensive experience in advanced heart failure therapies and a dedicated ECMO team, ECMO-assisted PCI demonstrated feasibility and safety in patients with ischemic cardiomyopathy. However, the rate of complete revascularization was modest at 58%. Despite the high-risk profile of the patients, ECMO-assisted PCI was associated with a significant improvement in LV functional remodeling and a favorable 12-month survival rate. Further prospective studies are needed to confirm these findings and to identify the optimal patient and device selection criteria for ECMO-assisted PCI.

Progressive Acute Lower Extremity Ischemia Resulting From Cardiac Myxoma Embolization: A Case Report.

Cardiac myxomas are the most common primary benign tumors of the heart. The occlusion of peripheral arteries and complete obstruction of the abdominal aorta by a tumor embolus presents with distinct clinical manifestations. Herein, we present the case of a 38-year-old male with acute paresthesia, muscle weakness, erythematous, and violaceous changes in skin color localized to the dorsum of the left forefoot initially treated as cutaneous vasculitis. Further studies revealed the total occlusion of the terminal abdominal aorta by a saddle embolus from a cardiac myxoma. A multidisciplinary team consisting of cardiothoracic and vascular surgeons were involved in treating the patient, which resulted in full resolution of the case. This paper details the progression of acute bilateral limb ischemia to chronic limb threatening ischemia resulting from the total occlusion of the terminal abdominal aorta by a saddle embolus.

Effects of Sevoflurane and Fullerenol C60 on the Heart and Lung in Lower-Extremity Ischemia-Reperfusion Injury in Streptozotocin-Induced Diabetes Mice.

Background and Objectives: Lower-extremity ischemia-reperfusion injury can induce distant organ ischemia, and patients with diabetes are particularly susceptible to ischemia-reperfusion injury. Sevoflurane, a widely used halogenated inhalation anesthetic, and fullerenol C60, a potent antioxidant, were investigated for their effects on heart and lung tissues in lower-extremity ischemia-reperfusion injury in streptozotocin (STZ)-induced diabetic mice. Materials and Methods: A total of 41 mice were divided into six groups: control (n = 6), diabetes-control (n = 7), diabetes-ischemia (n = 7), diabetes-ischemia-fullerenol C60 (n = 7), diabetes-ischemia-sevoflurane (n = 7), and diabetes-ischemia-fullerenol C60-sevoflurane (n = 7). Diabetes was induced in mice using a single intraperitoneal dose of 55 mg/kg STZ in all groups except for the control group. Mice in the control and diabetes-control groups underwent midline laparotomy and were sacrificed after 120 min. The DIR group underwent 120 min of lower-extremity ischemia followed by 120 min of reperfusion. In the DIR-F group, mice received 100 μg/kg fullerenol C60 intraperitoneally 30 min before IR. In the DIR-S group, sevoflurane and oxygen were administered during the IR procedure. In the DIR-FS group, fullerenol C60 and sevoflurane were administered. Biochemical and histological evaluations were performed on collected heart and lung tissues. Results: Histological examination of heart tissues showed significantly higher necrosis, polymorphonuclear leukocyte infiltration, edema, and total damage scores in the DIR group compared to controls. These effects were attenuated in fullerenol-treated groups. Lung tissue examination revealed more alveolar wall edema, hemorrhage, vascular congestion, polymorphonuclear leukocyte infiltration, and higher total damage scores in the DIR group compared to controls, with reduced injury parameters in the fullerenol-treated groups. Biochemical analyses indicated significantly higher total oxidative stress, oxidative stress index, and paraoxonase-1 levels in the DIR group compared to the control and diabetic groups. These levels were lower in the fullerenol-treated groups. Conclusions: Distant organ damage in the lung and heart tissues due to lower-extremity ischemia-reperfusion injury can be significantly reduced by fullerenol C60.

The Inhibition of γ-Aminobutyric Acid B1 Receptor Regulates Angiogenesis via the Hippo/YAP Signaling Pathway

Promoting the establishment of collateral circulation is essential for chronic lower extremity ischemia. However, no effective therapeutic drugs have yet been developed. Recent studies discovered that in the peripheral arteries, there are GABAB1 receptors expressed in endothelial cells and smooth muscle cells, these receptors may have some effects in regulating vascular functions, but the precise mechanism is not yet clear. This study explores the effect of GABAB1 receptor inhibition on angiogenesis and its regulatory mechanism. The expression of GABAB1 in HUVECs was knocked down using shRNA transfection, and effects in HUVECs' proliferation, migration, and tube formation ability were detected. Western blot and RT-PCR were used to verify the signal pathway. The murine hind limb ischemia model was used to verify the effect of CGP35348, an antagonist of GABAB1R, on the recovery of blood flow perfusion and angiogenesis in ischemic tissues. Cell proliferation, migration, and tube formation ability were improved after GABAB1 receptor knockdown in HUVECs. The phosphorylation of the HIPPO/YAP pathway decreased, while the effect of promoting angiogenesis increased. After treating the ischemic hindlimbs of mice with GABAB1 receptor antagonists, the blood flow perfusion recovered, and the angiogenesis increased. These findings demonstrate the effect of GABAB1 receptor inhibition on the HIPPO/YAP pathway in regulating angiogenesis, suggesting that inhibiting GABAB1 receptor levels might be a novel approach for chronic lower extremity ischemia diseases.

Predictive model for novel subtypes of patients undergoing lower extremity amputation for peripheral artery disease: An unsupervised machine learning study

BackgroundPeripheral artery disease (PAD) represents the frequently seen circulatory condition related to a risk of critical limb ischemia and amputation. Critical lower extremity ischemia may require amputation, and the outcomes vary. In this study, we developed an artificial intelligence (AI)-driven predictive model for PAD subtypes to assess risk among patients more precisely and accurately to predict disease progression. MethodsThe present retrospective study examined clinical data in PAD patents undergoing lower extremity amputation. The data were analyzed using an unsupervised machine learning algorithm (UMLA) for subgroup identification and risk stratification. The clustering result accuracy was validated by analyzing the follow-up data of clusters. Finally, we built the prediction model with binary logistic regression. ResultsIn total, we enrolled 507 cases into this work. Two distinct subgroups, consisting of Clusters 1 and 2, were identified by UMLA; those from Cluster 1 showed markedly poorer conditions and prognostic outcomes compared with those from Cluster 2. With regard to the new PAD subtype, we established a nomogram with eight predictive factors, including gender, age, smoking history, diabetes and coronary heart disease history, albumin levels, endovascular intervention, and amputation level. The nomogram could accurately categorize patients into two identified clusters, and the area under receiver operating characteristic curve was 0.861 (95 % confidence interval: 0.830–0.893). ConclusionIn this study, UMLA was used to identify new phenotypic subgroups among PAD cases who showed different risks of amputation. Our constructed AI-driven predictive model for PAD subtypes showed that it can be used for risk stratification and clinical management with high accuracy and reliability.

Endovascular intervention using combined percutaneous access in a patient with recurrence of critical ischemia after repeated bypass operations on arteries of the lower extremities (clinical case)

Unsatisfactory long-term results of shunting operations on the arteries of the lower extremities are most often caused by a stenotic process followed by thrombosis in the anastomotic zone, especially in combination with the progression of the underlying disease and the spread of obstructive atherosclerotic lesions on the inflow and outflow arteries. A clinical case of endovascular treatment of a patient with peripheral arterial disease is presented, who previously underwent 3 reconstructive bypass operations on the arteries of the lower extremities within 15 months before hospitalization, but again sought medical help due to the recurrence of critical ischemia of the left lower extremity. Considering the high risk of repeated open surgery due to the patient’s comorbidity (diabetes mellitus and extensive Q-myocardial infarction, suffered after the first bypass surgery), as well as gross scar changes after previous vascular operations, it was decided to perform endovascular intervention using a non-standard combined percutaneous approach. Iliac artery stenosis and post-thrombotic occlusion of the popliteal artery in the area of the distal anastomosis of the femoral-popliteal bypass graft on the left side were detected on the preoperative MSCT with intravenous contrast enhancement. Because of the gross postoperative scars, we could not use standard percutaneous approaches through any of the femoral arteries. Access through the arteries of the upper limbs also did not ensure the operation on all affected segments due to the long distance to the intervention zone and absence of instruments of the required length. Therefore, in order to maximally solve the tasks of the operation, we simultaneously used an antegrade left transaxillary access and a transpedal retrograde access through the left foot artery. Thus, the patient underwent simultaneous balloon angioplasty of stenoses of the common and external iliac arteries on the left side by transaxillary access, as well as balloon angioplasty and implantation of a coronary drug-eluting stent in the popliteal artery in the area of the distal anastomosis of the femoral-popliteal bypass graft by retrograde transpedal access on the left. As a result, the magistral arterial blood flow of the limb and the function of the shunt were completely restored with a good angiographic and clinical result.The applied methods of endovascular treatment have shown high efficiency and can be recommended as an alternative to traditional vascular surgery.

LncRNA H19/miR-107 regulates endothelial progenitor cell pyroptosis and promotes flow recovery of lower extremity ischemia through targeting FADD

BackgroundPeripheral artery disease (PAD) is an ischemic disease with a rising incidence worldwide. The lncRNA H19 (H19) is enriched in endothelial progenitor cells (EPCs), and transplantation of pyroptosis-resistant H19-overexpressed EPCs (oe-H19-EPCs) may promote vasculogenesis and blood flow recovery in PAD, especially with critical limb ischemia (CLI). MethodsEPCs isolated from human peripheral blood was characterized using immunofluorescence and flow cytometry. Cell proliferation was determined with CCK8 and EdU assays. Cell migration was assessed by Transwell and wound healing assays. The angiogenic potential was evaluated using tube formation assay. The pyroptosis pathway-related protein in EPCs was detected by western blot. The binding sites of H19 and FADD on miR-107 were analyzed using Luciferase assays. In vivo, oe-H19-EPCs were transplanted into a mouse ischemic limb model, and blood flow was detected by laser Doppler imaging. The transcriptional landscape behind the therapeutic effects of oe-H19-EPCs on ischemic limbs were examined with whole transcriptome sequencing. ResultsOverexpression of H19 in EPCs led to an increase in proliferation, migration, and tube formation abilities. These effects were mediated through pyroptosis pathway, which is regulated by the H19/miR-107/FADD axis. Transplantation of oe-H19-EPCs in a mouse ischemic limb model promoted vasculogenesis and blood flow recovery. Whole transcriptome sequencing indicated significant activation of vasculogenesis pathway in the ischemic limbs following treatment with oe-H19-EPCs. ConclusionsOverexpression of H19 increases FADD level by competitively binding to miR-107, leading to enhanced proliferation, migration, vasculogenesis, and inhibition of pyroptosis in EPCs. These effects ultimately promote the recovery of blood flow in CLI.

One-year limb salvage and quality of life following mechanical aspiration thrombectomy in patients with acute lower extremity ischemia

ObjectiveLower extremity acute limb ischemia (LE-ALI) is associated with high morbidity and mortality rates, and a burden on patient quality of life (QoL). There is limited medium- to long-term evidence on mechanical aspiration thrombectomy (MT) in patients with LE-ALI. The STRIDE study was designed to assess safety and efficacy of MT using the Indigo Aspiration System in patients with LE-ALI. Thirty-day primary and secondary endpoints and additional outcomes were previously published. Here, we report 365-day secondary endpoints and QoL data from STRIDE. MethodsSTRIDE was a multicenter, prospective, single-arm, observational cohort study that enrolled 119 patients across 16 sites in the United States and Europe. Patients were treated first-line with MT using the Indigo Aspiration System (Penumbra, Inc). The study completed follow-up in October 2023. Secondary endpoints at 365 days included target limb salvage and mortality. Additionally, the VascuQoL-6 questionnaire, developed for evaluating patient-centered QoL outcomes for peripheral arterial disease, was assessed at baseline and follow-up through 365 days. ResultsSeventy-three percent of patients (87/119) were available for 365-day follow-up. Mean age of these patients was 65.0 ± 13.3 years, and 44.8% were female. Baseline ischemic severity was classified as Rutherford I in 12.6%, Rutherford IIa in 51.7%, and Rutherford IIb in 35.6%. In general, baseline and disease characteristics (demographics, medical history, comorbidities, target thrombus) of these patients are similar to the enrolled cohort of 119 patients. The secondary endpoints at 365 days for target limb salvage was 88.5% (77/87) and mortality rate was 12.0% (12/100). VascuQoL-6 improved across all domains, with a median total score improvement from 12.0 (interquartile range, 9.0-15.0) at baseline to 19.0 (interquartile range, 16.0-22.0) at 365 days. ConclusionsThese 365-day results from STRIDE demonstrate that first-line MT with the Indigo Aspiration System for LE-ALI portray continued high target limb salvage rates and improved patient-reported QoL. These findings indicate Indigo as a safe and effective therapeutic option for LE-ALI.

Postoperative Casting of Below-Knee Amputation Reduces StumpComplications

Against the technological advances in limb salvage, below-the-knee amputation (BKA) remains a common procedure. Although most elective BKA is classified as clean operation, the reported stump complication rate is much higher than predicted. Postoperative casting (PC) may reduce the number of these complications. The aim of this study was to compare the efficacy of elastic bandage with knee immobilizer (EBKI) and PC in BKA stump complications. Retrospective cohort comparison design identified patients who underwent BKA between 2000 and 2023 for non-correctable critical limb ischemia (CLI), or excessive tissue loss secondary to CLI, infection, severe neuropathy, or the combination of these and stratified them into 2 cohorts based on their postoperative stump dressing: EBKI and PC. BKAs that were done for trauma or neoplastic processes were excluded. The primary outcome measures: wound healing in 6weeks and length of stay (LOS). stump injury, infection, dehiscence, necrosis, number of higher-level amputations, knee contracture, and post-BKA mobility with Special Interest Group of Amputee Medicine score. One hundred sixteen patients with 122 limbs (52 EBKI and 70 PC) were found who met inclusion criteria and analyzed. The groups were comparable in demographics and comorbidities and preoperative variables, including mobility. The primary wound healing at 6weeks was higher (P=0.007); wound dehiscence (P=0.01) and LOS (P=0.006) was lower in the PC group compared to EBKI group. The PC group achieved higher Special Interest Group of Amputee Medicine mobility score and lower number of contractures developed compared to the EBKI group. Applying and maintaining PC to the BKA stump during the first month of healing reduced the incidence of stump complications, shortened the LOS, and improved postrehabilitation mobility results. We found no effect of PC on postoperative infections, stump necrosis, and higher-level amputations.

Abstract 3017: Fluorine-18 Sodium Fluoride Positron Emission Tomography/ Computed Tomography Imaging Of Calcium Progression In Patients With Peripheral Artery Disease

Introduction: Peripheral artery disease (PAD) is an atherosclerotic disease that promotes lower extremity ischemia and is associated with necrosis, limb loss, and premature death. Fluorine-18 sodium fluoride ( 18 F-NaF) PET/CT imaging has been utilized for early detection of calcific disease progression in the coronary arteries; however, this technique has not been assessed in PAD to predict developing arterial calcification. Hypothesis: We hypothesized that 18 F-NaF PET/CT imaging could identify sites undergoing active microcalcification and predict the formation or expansion of vascular calcium. Methods: Patients with PAD (n=26) underwent 18 F-NaF PET/CT imaging at baseline and CT imaging 18 months later. Regions of interest were manually drawn on axial PET and CT images for the arteries of the symptomatic limb (totaling 8,001 arterial segments). Arterial uptake of 18 F-NaF was quantified and reported on a segment-by-segment basis as maximum standard uptake values (SUV max ). Baseline and 18-month CT images were co-registered to quantify serial changes in calcium density for each arterial segment using CT image cutoffs for calcium (≥130 Hounsfield Units). Differences in arterial uptake of 18 F-NaF were compared across 3 categories of segments: 1) no calcium at baseline or 18 months, 2) newly formed calcium and 3) existing calcified lesions with expansion of calcium. Results: Arterial segments containing newly formed calcium had significantly higher baseline uptake of 18 F-NaF than segments without calcium progression. Existing calcified arterial lesions with progression showed significantly higher 18 F-NaF uptake compared to segments with newly formed calcium and segments without calcium progression ( Figure 1 ). Conclusions: In conclusion, calcium progression can be detected and potentially predicted using 18 F-NaF PET/CT imaging, thereby providing a molecular imaging tool for monitoring PAD pathophysiology and responses to medical therapy.

The natural history of isolated common femoral endarterectomy for chronic limb-threatening ischemia

ObjectiveOcclusive disease of the common femoral artery can generate profound lower extremity ischemia as the normal collateral pathways from the profunda to the superficial femoral artery cannot adequately develop. In patients with lifestyle-limiting claudication, isolated common femoral endarterectomy (CFE) is highly effective. Because CFE does not provide direct, in-line flow to the plantar arch, it has been felt to provide inadequate revascularization to patients with chronic limb-threatening ischemia (CLTI). The purpose of this retrospective clinical study was to report and assess the natural history of selected patients with CLTI treated with isolated CFE (without concomitant infrainguinal revascularization). MethodsConsecutive CFEs performed in a large, urban hospital for CLTI between 2014 and 2021 were reviewed. Patient characteristics, limb, and anatomical stages using the Wound, Ischemia, foot Infection (WIfI) and Global Limb Anatomic Staging System were tabulated. Limb-specific and survival-related end points were analyzed. ResultsFifty-eight patients presenting with CLTI underwent isolated CFE (mean age, 74 ± 10 years; 62% male, 90% current or prior smoker). Comorbidities included diabetes (52%), coronary artery disease (55%), congestive heart failure (22%), and end-stage renal failure on hemodialysis (5%). Patients presented with either rest pain (36%) or tissue loss (64%); the latter group exhibited advanced limb threat (68% in WIfI stage 3 or 4). The majority of patients had associated severe infrainguinal disease (50% Global Limb Anatomic Staging Systems 3). After a median follow-up of 17 months (range, 10-29 months), vascular reintervention was required in 7 patients (12%). One patient (2%) required major limb amputation after presentation in WIfI stage 4 (W3I3fI0). Indeed, WIfI stage 4 was a significant univariate predictor of the need for subsequent infrainguinal bypass (P = .034). ConclusionsIsolated CFE as primary therapy in highly selected patients with CLTI was safe and effective. Index limb stage is predictive of the need for associated infrainguinal revascularization in this complex population.

Balloon angioplasty and stenting of lower extremity arteries in patients with critical limb ischemia

Lower extremity peripheral vascular disease is a typical, rapidly progressive, and disabling condition. In most patients, limb ischemia is detected at late stages of the disease. As a result, they are at high risk of limb loss, which makes a complete conventional treatment ineffective. In this situation, balloon angioplasty and stenting of lower extremity ar- teries are considered the optimal modern method of treating patients with critical limb ischemia. This study aims to evaluate the effectiveness of endovascular techniques to improve revascularization during the treatment of critical lower extremity ischemia. The research involved a comprehensive examination and endovascular treatment of 170 patients with occlusive-stenotic lesions of the lower extremity arteries. The patients were operated for critical ischemia between January 2016 and December 2022, and the effectiveness of the measures taken was analyzed. It was found that the pathology under the study requires timely diagnosis and identification of the severity of limb ischemia and circulatory disorders, with the subsequent preparation of an appropriate treatment plan. The authors discussed the main problems accompanying balloon angioplasty and stenting of the lower extremity arteries in patients with critical limb ischemia. Also, the experience of developed countries in the optimization and improvement of the studied tech- nique was studied. It has been proven that the diagnosis of lower extremity vascular disease is related to specific difficulties. However, it can be made on an outpatient basis by analyzing medical examination data and simple labor- atory methods. The authors also examined the feasibility and prospects of balloon angioplasty and stenting of the lower extremity arteries in patients with critical limb ischemia. The re-search findings have a practical value for improving the treatment of patients with occlusive and stenotic lesions of the lower extremities, as well as for improving the effec-tiveness of balloon angioplasty and stenting.

Endovascular Perclose ProGlide complication puncture site, treated successful by cutting balloon dilatation: A case report and literature review.

Perclose ProGlide were created as preferred for puncture site closure of femoral artery. Femoral artery occlusion is one of the serious device-related complications. This report presents a continuous endovascular technique combined with peripheral cutting balloon (PCB) treatment for a case of a 32s woman diagnosed with lower extremity ischaemia caused by right superficial femoral artery (SFA) occlusion following the use of the Perclose ProGlide system in minimally invasive cardiac surgery. During the primary operation, limb ischaemia symptoms were relieved with vessel perfusion and reconstruction after regular balloon dilatation. A secondary operation was conducted 6 weeks later, and the obstructive lesions were recanalised without residual stenosis after PCB dilatation. No vessel-related adverse events such as dissection, rupture or distal embolisation occurred during the perioperative period. The patient recovered uneventfully after the operation, with complete alleviation of symptoms. Follow-up computed tomography angiography 3 month post-operatively revealed an undeformed shape and excellent patency of the right SFA.

Poor Limb Prognosis of Patients with Chronic Limb-Threatening Ischemia on Hemodialysis: A Retrospective Observational Study Based on the Global Limb Anatomic Staging System

The Global Limb Anatomic Staging System (GLASS) has been widely used to evaluate patients with chronic limb-threatening ischemia (CLTI). As end-stage kidney disease (ESKD) is a well-known CLTI risk factor, we aimed to determine whether patients on hemodialysis (HD) have a worse limb prognosis than those without ESKD, considering the same GLASS background. The data of 445 patients who underwent surgical and/or endovascular revascularization procedures for lower extremity ischemia were retrospectively collected in our division between 2005 and 2018. The major amputation rate and amputation-free survival (AFS) were compared between HD and non-HD patients. Among the 215 (48%) patients receiving HD, 58 limbs required major amputation (27% limb loss rate). Among the non-HD group, the limb loss rate was 13% (P<0.0001). The overall AFS was significantly worse in patients receiving HD than those not (P<0.0001). The AFS was significantly worse in HD patients when comparing GLASS-standardized subgroups. Patients with CLTI who were receiving HD had a worse limb prognosis than those not receiving, even when considering the same GLASS classification. Furthermore, there is a need for an ideal guideline focused on ESKD-directed peripheral artery disease.

A machine learning-based approach to identify peripheral artery disease using texture features from contrast-enhanced magnetic resonance imaging

Diagnosing and assessing the risk of peripheral artery disease (PAD) has long been a focal point for medical practitioners. The impaired blood circulation in PAD patients results in altered microvascular perfusion patterns in the calf muscles which is the primary location of intermittent claudication pain. Consequently, we hypothesized that changes in perfusion and increase in connective tissue could lead to alterations in the appearance or texture patterns of the skeletal calf muscles, as visualized with non-invasive imaging techniques. We designed an automatic pipeline for textural feature extraction from contrast-enhanced magnetic resonance imaging (CE-MRI) scans and used the texture features to train machine learning models to detect the heterogeneity in the muscle pattern among PAD patients and matched controls. CE-MRIs from 36 PAD patients and 20 matched controls were used for preparing training and testing data at a 7:3 ratio with cross-validation (CV) techniques. We employed feature arrangement and selection methods to optimize the number of features. The proposed method achieved a peak accuracy of 94.11% and a mean testing accuracy of 84.85% in a 2-class classification approach (controls vs. PAD). A three-class classification approach was performed to identify a high-risk PAD sub-group which yielded an average test accuracy of 83.23% (matched controls vs. PAD without diabetes vs. PAD with diabetes). Similarly, we obtained 78.60% average accuracy among matched controls, PAD treadmill exercise completers, and PAD exercise treadmill non-completers. Machine learning and imaging-based texture features may be of interest in the study of lower extremity ischemia.

Investigation of the effects of ellagic, vanillic and rosmarinic acid on reperfusion-induced renal injury.

The aim of this study was to investigate the effects of ellagic, vanillic and rosmarinic acid on reperfusion-related kidney damage, developed in an experimental lower-extremity ischaemia/reperfusion (I/R) model. Forty-eight female Sprague-Dawley rats were divided into six groups. A median laparotomy and dissection were performed. In the I/R group, 60 minutes of ischaemia followed by 120 minutes of reperfusion was achieved. In addition one group was given 100 mg/kg ellagic acid, one group was given 12 mg/kg vanillic acid, one group was given 50 mg/kg rosmarinic acid and one group was given all three drugs 15 minutes before clamp removal. Bilateral kidney and blood samples were taken in all groups. Tubular epithelial degeneration, necrosis of the tubule epithelium and vessel wall thickening were significantly higher in the I/R group. Some parameters in the groups that were given drugs were found to be lower than in the I/R group and close to that of the control group. Total oxidant status (TOS) and oxidative stress index (OSI) were significantly higher and total antioxidant status (TAS) was significantly lower in the I/R group. Although not statistically significant in the groups given drugs, TAS was higher, and TOS and OSI were lower than in the I/R group. The antioxidant effect of ellagic, vanillic and rosmarinic acid administration may have beneficial effects on renal damage after reperfusion in acute lower-extremity ischaemia. This study is expected to provide information for future clinical trials.