ASAP─Automated Sonication-Free Acid-Assisted Proteomes─from Cells and FFPE Tissues.

Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable resource for retrospective studies, but protein extraction and subsequent sample processing steps have been shown to be challenging for mass spectrometry (MS) analysis. Streamlined high-throughput sample preparation workflows are essential for efficient peptide extraction from complex clinical specimens such as fresh frozen tissues or FFPE. Overall, proteome analysis has gained significant improvements in the instrumentation, acquisition methods, sample preparation workflows, and analysis pipelines, yet even the most recent FFPE workflows remain complex and are not readily scalable. Here, we present an optimized workflow for automated sonication-free acid-assisted proteome (ASAP) extraction from FFPE sections. ASAP enables efficient protein extraction from FFPE specimens, achieving similar proteome coverage as established methods using expensive sonicators, resulting in reduced sample processing time. The broad applicability of ASAP on archived pediatric tumor FFPE specimens resulted in high-quality data with increased proteome coverage and quantitative reproducibility. Our study demonstrates the practicality and superiority of the ASAP workflow as a streamlined, time- and cost-effective pipeline for high-throughput FFPE proteomics of clinical specimens.

The importance of inflammation control for the treatment of chronic diabetic wounds.

Diabetic chronic wounds cause massive levels of patient suffering and economic problems worldwide. The state of chronic inflammation arises in response to a complex combination of diabetes mellitus-related pathophysiologies. Advanced treatment options are available; however, many wounds still fail to heal, exacerbating morbidity and mortality. This review describes the chronic inflammation pathophysiologies in diabetic ulcers and treatment options that may help address this dysfunction either directly or indirectly. We suggest that treatments to reduce inflammation within these complex wounds may help trigger healing.

Incidence of major complications from embolo-sclerotherapy of head and neck vascular malformations in a single specialist centre.

OBJECTIVE: Current data on the nature and rate of major complications for embolo-sclerotherapy (EST) of vascular malformations are scarce. However, even fewer studies focus on vascular malformations specific to the head and neck, which confer an increased specific risk of airway compromise, neurologic and ophthalmologic injury. More understanding is required surrounding the type and incidence of complications to improve treatment planning and informed consent. Therefore, this study aimed to review major complications secondary to EST of head and neck vascular malformations over a 5-year period in a single specialized multidisciplinary centre for vascular anomalies. METHODS: All interventions were decided by the multidisciplinary team. Demographic, procedural and complication data between 1st January 2013 and 31st December 2017 were prospectively documented in a dedicated database and analysed. EST of high-flow vascular malformations (HFVMs) was performed by selective catheter angiography or direct injection, and by direct injection only for low-flow vascular malformations (LFVMs). Major complications were defined as any tissue or functional damage caused by direct injection, distal embolization or tissue reaction and were decided by the multidisciplinary team. RESULTS: Forty-eight patients (median age of 35 years; range of 14-70 years; 18 men and 30 women) had 100 EST procedures for head and neck vascular malformation. Of these, 14 patients had EST for HFVM and 34 patients for LFVM, total 43 and 57 procedures, respectively. Overall, five patients with HFVM developed major complications from EST when compared with two patients with LFVM (p = 0.0167). Two patients required pre-emptive tracheostomy due to risk of post-operative airway compromise. Overall, seven (14.6%) patients experienced major complication from EST. In the HFVM group, major complications from EST occurred in five patients; four cases of tissue ulceration and necrosis (two needed debridement, one healed with resultant fibrosis that impeded speech and one resolved spontaneously) and one post-procedural airway compromise requiring tracheostomy. Meanwhile, in the LFVM group, major complications occurred in two patients; one case of severe necrosis involving the alar cartilage, lip and cheek requiring debridement and reconstruction under plastics and one simple cellulitis. No patients sustained stroke or vision impairment. CONCLUSIONS: EST is relatively safe for head and neck vascular malformations in a high-volume experienced centre. Our major complication rate of 14.6% per patient (35.7% for HFVM; 5.9% for LFVM) or 7% per procedure (11.6% for HFVM; 3.5% LFVM) compares favourably with published data from other centres. These data will improve treatment planning and informed consent for EST for both HFVM and LFVM of the head and neck.

Patient radiation exposure from embolo-sclerotherapy of peripheral vascular malformations.

OBJECTIVE: Embolo-sclerotherapy (EST) is the mainstay therapy for peripheral vascular malformations that involves the exposure of patients to ionizing radiation. We analyzed the radiation exposure to patients from EST of peripheral vascular malformations during a 5-year period in a single specialist center. METHODS: All patients who had undergone EST at a single specialist center for peripheral vascular malformations from January 1, 2013 to January 8, 2018 were identified from a prospectively collected database. Data collection included basic demographics, procedure date, anatomic site, type of vascular malformations, and procedural details. Radiation exposure, measured as the dose-area product (DAP) and fluoroscopy time, of all patients who had undergone EST during the study period were retrospectively reviewed. Statistical analysis was performed using the Mann-Whitney U and Kruskal-Wallis tests for comparison between subgroups. P < .05 was considered statistically significant. RESULTS: A total of 237 patients (median age, 30 years; range, 1-73 years) had undergone 419 EST sessions during the study period. Of the 237 patients, 61 (25.7%) had had arteriovenous malformations (AVMs) and had undergone 140 EST sessions (33.4%) and 176 (74.3%) had had venous and lymphatic malformations and had undergone 279 EST sessions (66.6%). Patients with AVMs had undergone a median of 2 procedures (range, 1-13) compared with a median of 1 (range, 1-6) for venous and lymphatic malformations within the study period. The median DAP for the single and cumulative EST for peripheral vascular malformations was 1.26 Gycm2 (range, 0.00-698.36 Gycm2) and 1.91 Gycm2 (range, 0.00-1300.24 Gycm2), respectively. The median fluoroscopy time for single and cumulative EST was 19 seconds (range, 1-3846 seconds) and 30 seconds (range, 1-5843 seconds), respectively. Significantly greater patient radiation exposure, in DAP and fluoroscopy time, was measured for single and cumulative EST for AVMs compared with venous and lymphatic malformations (P < .01 for both; Mann-Whitney U test). A significant difference in DAP but not fluoroscopy time was found when the anatomic areas of vascular malformations were compared. CONCLUSIONS: Patient radiation exposure for EST for peripheral vascular malformations, measured in DAP and fluoroscopy time, appeared to be generally less than that reported for endovascular arterial and deep venous interventions. However, some patients with peripheral vascular malformations received relatively high radiation doses. Further studies to investigate the risk factors and long-term side effects of radiation exposure in these patients and strategies to reduce these are required.

Sensitive Determination of Proteolytic Proteoforms in Limited Microscale Proteome Samples.

Protein N termini unambiguously identify truncated, alternatively translated or modified proteoforms with distinct functions and reveal perturbations in disease. Selective enrichment of N-terminal peptides is necessary to achieve proteome-wide coverage for unbiased identification of site-specific regulatory proteolytic processing and protease substrates. However, many proteolytic processes are strictly confined in time and space and therefore can only be analyzed in minute samples that provide insufficient starting material for current enrichment protocols. Here we present High-efficiency Undecanal-based N Termini EnRichment (HUNTER), a robust, sensitive and scalable method for the analysis of previously inaccessible microscale samples. HUNTER achieved identification of >1000 N termini from as little as 2 µg raw HeLa cell lysate. Broad applicability is demonstrated by the first N-terminome analysis of sorted human primary immune cells and enriched mitochondrial fractions from pediatric cancer patients, as well as protease substrate identification from individual Arabidopsis thaliana wild type and Vacuolar Processing Enzyme-deficient mutant seedlings. We further implemented the workflow on a liquid handling system and demonstrate the feasibility of clinical degradomics by automated processing of liquid biopsies from pediatric cancer patients.

Incidence of major complication following embolo-sclerotherapy for upper and lower extremity vascular malformations.

OBJECTIVE: The current literature on the major complications of embolo-sclerotherapy of upper and lower extremity vascular malformations is scarce. Evaluating and understanding the rates and types of potential major complications of embolo-sclerotherapy of vascular malformations help treatment planning and informed consent. Therefore, this study reviewed major complications following embolo-sclerotherapy of all upper and lower extremity vascular malformations in a single specialized multidisciplinary vascular malformation center over a 5-year period. METHODS: All patients with vascular malformations underwent multidisciplinary directed intervention. Demographic, procedural, follow-up, and complication data were collected prospectively in a dedicated database, and reviewed retrospectively. Major complications for upper and lower extremity vascular malformations from 1 January 2013 to 31 December 2017 were analyzed. All embolo-sclerotherapies of high-flow vascular malformations (HFVMs) were performed under selective catheter angiography and direct injection, but low-flow vascular malformations (LFVM) with direct injection only. Major complications were defined as any tissue or functional damage caused by direct injection, distal embolization, or tissue reaction. RESULTS: Seventy patients (median age of 25 years; 44 males and 26 females) had 150 embolo-sclerotherapy procedures for upper extremity vascular malformation. Of these, 28 patients had embolo-sclerotherapy for HFVM and 42 patients for LFVM; total 78 and 72 procedures, respectively. A total of 107 patients (median age of 26 years; 42 males and 65 females) had 160 embolo-sclerotherapy interventions for lower extremity vascular malformations. Of these, 18 patients had embolo-sclerotherapy for HFVM and 89 patients for LFVM; total of 30 and 130 procedures, respectively. The overall major complication rates following embolo-sclerotherapy of upper and lower extremity vascular malformations were 14.3% and 4.7%, respectively (P = 0.030). In the upper extremity HFVM group, major complications from embolo-sclerotherapy occurred in five patients; three ischemic fingers requiring amputation and two skin ulcerations. Meanwhile, in the upper extremity LFVM group, major complications occurred in five patients; one median nerve injury requiring nerve grafting and hand therapy, one hand contracture requiring tendon release, and three skin ulcerations. There was only one major complication, which was cellulitis in the lower extremity HFVM group. In the lower extremity LFVM group, major complications occurred in four patients; two skin ulcerations, one cellulitis, and one deep vein thrombosis. CONCLUSIONS: Embolo-sclerotherapy is relatively safe for upper and lower extremity vascular malformations in a high-volume experienced center where our major complication rates were 14.3% and 4.7%, respectively, which compare favorably or similar to those reported in most recent literature. These outcomes will direct treatment strategies to avoid local and systemic toxic complications in the upper and lower extremity, for both HFVM and LFVM, and to improve informed consent.

Transmission of infection among health care personnel performing surgical tracheostomies on COVID-19 patients.

BACKGROUND: Staff and patient safety are of paramount importance while performing a surgical tracheostomy (ST) during the corona virus disease (COVID-19) pandemic. The aim was to assess the incidence of COVID-19 infection among the healthcare personnel (HCP) performing ST on COVID-19 patients. METHODS: One hundred and twenty-two HCP participating in 71 ST procedures performed at our institution between 26th March 2020 and 27th May 2020 were identified. A COVID-19 health questionnaire was distributed among staff with their consent. Data related to the presence of COVID-19 symptoms (new onset continuous cough, fever, loss of taste and/or loss of smell) among HCP involved in ST as well as patient related data were collected. RESULTS: Of the HCP who responded, eleven (15%,11/72) reported key COVID-19 symptoms and went into self-isolation. Ten members from this group underwent a COVID-19 swab test and three tested positive. Only one HCP attended hospital for symptomatic treatment, none required hospitalisation. Sixty percent (43/72) of the responders had a COVID-19 antibody test with a positive rate of 18.6% (8/43). Among the patients undergoing a ST, 67% (37/55) required a direct intensive care unit (ICU) admission; the mean age was 58 years (29-78) with a male preponderance (65.5%). The median time from intubation to ST was 15 days (range 5-33,IQR = 9). The overall mortality was 11% (6/55). CONCLUSIONS: ST can be carried out safely with strict adherence to both, personnel protective equipment and ST protocols which are vital to mitigate the potential transmission of COVID-19 to the HCP.

Endothelial C-Type Natriuretic Peptide Is a Critical Regulator of Angiogenesis and Vascular Remodeling.

BACKGROUND: Angiogenesis and vascular remodeling are complementary, innate responses to ischemic cardiovascular events, including peripheral artery disease and myocardial infarction, which restore tissue blood supply and oxygenation; the endothelium plays a critical function in these intrinsic protective processes. C-type natriuretic peptide (CNP) is a fundamental endothelial signaling species that coordinates vascular homeostasis. Herein, we sought to delineate a central role for CNP in angiogenesis and vascular remodeling in response to ischemia. METHODS: The in vitro angiogenic capacity of CNP was examined in pulmonary microvascular endothelial cells and aortic rings isolated from wild-type, endothelium-specific CNP-/-, global natriuretic peptide receptor (NPR)-B-/- and NPR-C-/- animals, and human umbilical vein endothelial cells. These studies were complemented by in vivo investigation of neovascularization and vascular remodeling after ischemia or vessel injury, and CNP/NPR-C expression and localization in tissue from patients with peripheral artery disease. RESULTS: Clinical vascular ischemia is associated with reduced levels of CNP and its cognate NPR-C. Moreover, genetic or pharmacological inhibition of CNP and NPR-C, but not NPR-B, reduces the angiogenic potential of pulmonary microvascular endothelial cells, human umbilical vein endothelial cells, and isolated vessels ex vivo. Angiogenesis and remodeling are impaired in vivo in endothelium-specific CNP-/- and NPR-C-/-, but not NPR-B-/-, mice; the detrimental phenotype caused by genetic deletion of endothelial CNP, but not NPR-C, can be rescued by pharmacological administration of CNP. The proangiogenic effect of CNP/NPR-C is dependent on activation of Gi, ERK1/2, and phosphoinositide 3-kinase γ/Akt at a molecular level. CONCLUSIONS: These data define a central (patho)physiological role for CNP in angiogenesis and vascular remodeling in response to ischemia and provide the rationale for pharmacological activation of NPR-C as an innovative approach to treating peripheral artery disease and ischemic cardiovascular disorders.

Hyperglycaemia and Ischaemia Impair Wound Healing via Toll-like Receptor 4 Pathway Activation in vitro and in an Experimental Murine Model.

OBJECTIVE: Diabetes mellitus has reached epidemic proportions. Foot ulceration is a multifactorial complication of diabetes associated with marked morbidity and mortality. Innate immune Toll-like receptor 4 (TLR4) mediated inflammation has been implicated in the systemic pathogenesis of diabetes and may contribute to impairment of wound healing. This study investigates the effect of high glucose and hypoxic conditions on TLR4 activation and signalling in vitro and in vivo. METHODS: Fibroblasts cultured at physiological glucose concentration (5.5 mM) were exposed to glucose concentrations from 0 mM to 25 mM, with duplicates placed in a hypoxic chamber. TLR4 inhibition was assessed in the 25 mM glucose groups. Diabetes was induced in wild type (WT) and TLR4 knockout (KO) C57BL/6 mice by intraperitoneal injection of low dose streptozocin (STZ). Hindlimb ischaemia was induced by femoral artery ligation four weeks post streptozocin, and a full thickness 4 mm skin wound inflicted below the knee. Wound healing was assessed via digital planimetry on days 3, 7, and 14 post surgery. RESULTS: Hypoxic and high glucose (25 mM) conditions led to an increase in TLR4 protein expression, apoptosis, and interleukin (IL)-6 release. Inhibition with a TLR4 neutralising antibody and specific TLR4 antagonist ameliorated the effects of high glucose and ischaemia (p < .05). In vivo, wound healing was significantly impaired in the diabetic ischaemic group at day 14 (p < .05). Diabetic ischaemic wounds in TLR4 KO mice exhibited significantly improved healing rates compared with those in WT mice at all time points. CONCLUSION: Hypoxia stimulates upregulation of TLR4 protein expression and this effect is exaggerated by hyperglycaemia. In TLR4 KO mice, there is a significant improvement in the healing of diabetic ischaemic wounds compared with WT. It is suggested that a synergistic effect between hypoxia and hyperglycaemia impairing wound healing exists, through TLR4 mediated inflammation.

Emerging importance of molecular pathogenesis of vascular malformations in clinical practice and classifications.

Vascular malformations occur during early vascular development resulting in abnormally formed vessels that can manifest as arterial, venous, capillary or lymphatic lesions, or in combination, and include local tissue overdevelopment. Vascular malformations are largely caused by sporadic somatic gene mutations. This article aims to review and discuss current molecular signaling pathways and therapeutic targets for vascular malformations and to classify vascular malformations according to the molecular pathways involved. A literature review was performed using Embase and Medline. Different MeSH terms were combined for the search strategy, with the aim of encompassing all studies describing the classification, pathogenesis, and treatment of vascular malformations. Major pathways involved in the pathogenesis of vascular malformations are vascular endothelial growth factor (VEGF), Ras/Raf/MEK/ERK, angiopoietin-TIE2, transforming growth factor beta (TGF-ß), and PI3K/AKT/mTOR. These pathways are involved in controlling cellular growth, apoptosis, differentiation, and proliferation, and play a central role in endothelial cell signaling and angiogenesis. Many vascular malformations share similar aberrant molecular signaling pathways with cancers and inflammatory disorders. Therefore, selective anticancer agents and immunosuppressants may be beneficial in treating vascular malformations of specific mutations. The current classification systems of vascular malformations, including the International Society of the Study of Vascular Anomalies (ISSVA) classification, are primarily observational and clinical, and are not based on the molecular pathways involved in the pathogenesis of the condition. Several molecular pathways with potential therapeutic targets have been demonstrated to contribute to the development of various vascular anomalies. Classifying vascular malformations based on their molecular pathogenesis may improve treatment by determining the underlying nature of the condition and their potential therapeutic target.

Toll-like receptors 2 and 6 mediate apoptosis and inflammation in ischemic skeletal myotubes.

Critical limb ischemia (CLI) is associated with skeletal muscle damage. However, the pathophysiology of the muscle damage is poorly understood. Toll-like receptors (TLR) have been attributed to play a role in ischemia-induced tissue damage but their role in skeletal muscle damage in CLI is unknown. TLR2 and TLR6 expression was found to be upregulated in skeletal muscle of patients with CLI. In vitro, ischemia led to upregulation of TLR2 and TLR6 by myotubes, and activation of the downstream TLR signaling pathway. Ischemia-induced activation of the TLR signaling pathway led to secretion of the pro-inflammatory cytokine interleukin-6 and muscle apoptosis, which were abrogated by neutralising TLR2 and TLR6 antibodies. Our study demonstrates that TLR2 and TLR6 are upregulated in ischemic muscle and play a role in ischemia-induced muscle damage. Thus, manipulating the TLR pathway locally may be of potential therapeutic benefit.

Successful Repair of a Vasculopathic Aneurysmal Brachial Artery in a Patient with Type 1 Neurofibromatosis.

Vasculopathy is a well-recognized abnormality associated with neurofibromatosis type 1(NF1) and may cause stenoses, aneurysms, and arteriovenous malformations. We report a challenging case of a woman with NF1, who presented with spontaneous rupture of a brachial aneurysm around her right elbow, on a background of previous debulking and soft tissue reconstructive surgery in the same arm. She underwent successful delayed reconstruction of the brachial artery using an autologous great saphenous vein graft.

Potential role of erythropoietin receptors and ligands in attenuating apoptosis and inflammation in critical limb ischemia.

OBJECTIVE: Managing critical limb ischemia (CLI) is challenging. Furthermore, ischemic myopathy prevents good functional outcome after revascularization. Hence, we have focused on limiting the tissue damage rather than angiogenesis, which has traditionally been the motivation to develop nonsurgical treatments for CLI. Erythropoietin (EPO) protects ischemic tissue, and this property may also benefit CLI. The objective of this study was to examine the expression of the tissue-protective EPO receptor complex (EPOR-CD131 [ß-chain of interleukin (IL)-3/IL-5/granulocyte macrophage colony-stimulating factor receptor]) in skeletal muscle obtained from humans with CLI. Because native EPO is thrombogenic, the antiapoptotic and anti-inflammatory effects of a nonhematopoietic helix-B peptide of EPO (ARA 290) were investigated on ischemic myotubes in vitro. METHODS: Tissue was obtained from gastrocnemius muscle of 12 patients undergoing amputation for CLI and from 12 patients without limb ischemia. The expression of EPOR and CD131 was demonstrated by immunohistochemistry and Western blot. A validated in vitro model of myotube ischemia was used in which mature C2C12 myotubes were cultured 6 to 12 hours in a depleted media and gas mixture (20% CO2 and 80% N2). The myotubes were pretreated with EPO or ARA 290 before exposure to simulated ischemia. Apoptosis and cell death were determined by cleaved caspase-3 assay and lactate dehydrogenase release assay. Enzyme-linked immunosorbent assay measured the inflammatory cytokines. RESULTS: EPOR and CD131 were expressed and significantly upregulated in CLI (average optical density [OD] in Western blot [control vs CLI] EPOR, 0.05 U vs 0.1 U; CD131, 0.10 U vs 0.22 U; P < .01). There was colocalization of EPOR and CD131 in the sarcolemma (cell membrane) of the skeletal myofiber. There was no difference in the distribution of colocalization between the CLI and the normal muscle. The ischemic myotubes treated by ARA 290 in vitro had a significantly decreased number of apoptotic cells (ischemia vs ischemia plus ARA 290: 71.1% vs 55.1%; P < .01), cleaved caspase-3 (OD of ischemia vs ischemia plus ARA 290: 0.15 U vs 0.02 U; P < .01), lactate dehydrogenase release (ischemia vs ischemia plus ARA 290: 32.5 U/L vs 21.3 U/L; P < .01), and IL-6 release (OD at 450 nm, ischemia vs ischemia plus ARA 290: 0.18 vs 0.13; P < .01). CONCLUSIONS: This study demonstrates the expression and the upregulation of EPOR and CD131 in CLI and also shows that EPOR and CDI are colocalized in the cell membrane of both ischemic and control muscle fiber. The in vitro experiments demonstrate that ARA 290 decreases inflammation and apoptosis of ischemic myotubes. ARA 290 may potentially be used as adjunctive treatment for CLI.

Role of toll-like receptor 4 in skeletal muscle damage in chronic limb-threatening ischemia.

Objective: Toll-like receptors (TLRs) are key pattern recognition receptors in the innate immune system. In particular, the TLR4-mediated immune response has been implicated in ischemia-induced tissue injury. Mounting evidence supports a detrimental role of the innate immune system in the pathophysiology of skeletal muscle damage in patients with chronic limb-threatening ischemia (CLTI), in whom patient-oriented functional outcomes are poor. The overall aim of this study was to investigate the potential role of TLR4 in skeletal muscle dysfunction and damage in CLTI. Methods: The role of TLR4 in ischemic muscle was investigated by (1) studying TLR4 expression and distribution in human gastrocnemius muscle biopsies, (2) evaluating the functional consequences of TLR4 inhibition in myotubes derived from human muscle biopsies, and (3) assessing the therapeutic potential of modulating TLR4 signaling in ischemic muscle in a mouse hindlimb ischemia model. Results: TLR4 was found to be expressed in human muscle biopsies, with significant upregulation in samples from patients with CLTI. In vitro studies using cultured human myotubes demonstrated upregulation of TLR4 in ischemia, with activation of the downstream signaling pathway. Inhibition of TLR4 before ischemia was associated with reduced ischemia-induced apoptosis. Upregulation of TLR4 also occurred in ischemia in vivo and TLR4 inhibition was associated with decreased inflammatory cell infiltration and diminished apoptosis in the ischemic limb. Conclusions: TLR4 is upregulated and activated in ischemic skeletal muscle in patients with CLTI. Modulating TLR4 signaling in vitro and in vivo was associated with attenuation of ischemia-induced skeletal muscle damage. This strategy could be explored further for potential clinical application.

Modelling lower-limb peripheral arterial disease using clinically available datasets: impact of inflow boundary conditions on hemodynamic indices for restenosis prediction.

BACKGROUND AND OBJECTIVES: The integration of hemodynamic markers as risk factors in restenosis prediction models for lower-limb peripheral arteries is hindered by fragmented clinical datasets. Computed tomography (CT) scans enable vessel geometry reconstruction and can be obtained at different times than the Doppler ultrasound (DUS) images, which provide information on blood flow velocity. Computational fluid dynamics (CFD) simulations allow the computation of near-wall hemodynamic indices, whose accuracy depends on the prescribed inlet boundary condition (BC), derived from the DUS images. This study aims to: (i) investigate the impact of different DUS-derived velocity waveforms on CFD results; (ii) test whether the same vessel areas, subjected to altered hemodynamics, can be detected independently of the applied inlet BC; (iii) suggest suitable DUS images to obtain reliable CFD results. METHODS: CFD simulations were conducted on three patients treated with bypass surgery, using patient-specific DUS-derived inlet BCs recorded at either the same or different time points than the CT scan. The impact of the chosen inflow condition on bypass hemodynamics was assessed in terms of wall shear stress (WSS)-derived quantities. Patient-specific critical thresholds for the hemodynamic indices were applied to identify critical luminal areas and compare the results with a reference obtained with a DUS image acquired in close temporal proximity to the CT scan. RESULTS: The main findings indicate that: (i) DUS-derived inlet velocity waveforms acquired at different time points than the CT scan led to statistically significantly different CFD results (p<0.001); (ii) the same luminal surface areas, exposed to low time-averaged WSS, could be identified independently of the applied inlet BCs; (iii) similar outcomes were observed for the other hemodynamic indices if the prescribed inlet velocity waveform had the same shape and comparable systolic acceleration time to the one recorded in close temporal proximity to the CT scan. CONCLUSIONS: Despite a lack of standardised data collection for diseased lower-limb peripheral arteries, an accurate estimation of luminal areas subjected to altered near-wall hemodynamics is possible independently of the applied inlet BC. This holds if the applied inlet waveform shares some characteristics - derivable from the DUS report - as one matching the acquisition time of the CT scan.

A systematic review of clinical and biomechanical engineering perspectives on the prediction of restenosis in coronary and peripheral arteries.

Objective: Restenosis is a significant complication of revascularization treatments in coronary and peripheral arteries, sometimes necessitating repeated intervention. Establishing when restenosis will happen is extremely difficult due to the interplay of multiple variables and factors. Standard clinical and Doppler ultrasound scans surveillance follow-ups are the only tools clinicians can rely on to monitor intervention outcomes. However, implementing efficient surveillance programs is hindered by health care system limitations, patients' comorbidities, and compliance. Predictive models classifying patients according to their risk of developing restenosis over a specific period will allow the development of tailored surveillance, prevention programs, and efficient clinical workflows. This review aims to: (1) summarize the state-of-the-art in predictive models for restenosis in coronary and peripheral arteries; (2) compare their performance in terms of predictive power; and (3) provide an outlook for potentially improved predictive models. Methods: We carried out a comprehensive literature review by accessing the PubMed/MEDLINE database according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search strategy consisted of a combination of keywords and included studies focusing on predictive models of restenosis published between January 1993 and April 2023. One author independently screened titles and abstracts and checked for eligibility. The rest of the authors independently confirmed and discussed in case of any disagreement. The search of published literature identified 22 studies providing two perspectives-clinical and biomechanical engineering-on restenosis and comprising distinct methodologies, predictors, and study designs. We compared predictive models' performance on discrimination and calibration aspects. We reported the performance of models simulating reocclusion progression, evaluated by comparison with clinical images. Results: Clinical perspective studies consider only routinely collected patient information as restenosis predictors. Our review reveals that clinical models adopting traditional statistics (n = 14) exhibit only modest predictive power. The latter improves when machine learning algorithms (n = 4) are employed. The logistic regression models of the biomechanical engineering perspective (n = 2) show enhanced predictive power when hemodynamic descriptors linked to restenosis are fused with a limited set of clinical risk factors. Biomechanical engineering studies simulating restenosis progression (n = 2) are able to capture its evolution but are computationally expensive and lack risk scoring for individual patients at specific follow-ups. Conclusions: Restenosis predictive models, based solely on routine clinical risk factors and using classical statistics, inadequately predict the occurrence of restenosis. Risk stratification models with increased predictive power can be potentially built by adopting machine learning techniques and incorporating critical information regarding vessel hemodynamics arising from biomechanical engineering analyses.

Early follow-up quality of life and mental health of patients with congenital vascular malformations cared for in a multi-disciplinary specialist centre.

OBJECTIVE: The study aimed to evaluate the early follow-up quality of life (QoL), pain and mental health of patients with congenital vascular malformation (CVM) from a variety of treatment options. METHODS: All patients with CVM who received care and had follow-up between February 1st 2018 and January 31st 2020 were included. The health-related QoL, pain, and mental health were assessed with RAND Health Care 36-Item Short Form Survey (SF-36), visual analogue score for pain (VAS-P) and Hospital Anxiety and Depression Scale (HADS). Paired t-test was used for all analyses. p < .05 were considered significant. RESULTS: In total, 110 patients with a mean age of 36.9 years were included in this study. In all patients following care, significant improvement was found in the bodily pain domain of SF-36 and VAS-P (both p = .01). This was largely driven by high-flow vascular malformation patients who responded better to embolo-sclerotherapy, which revealed significant improvement in the bodily pain domain of SF-36 (p = .002) and VAS-P (p = .02). Patients who received supportive treatment only reported significant improvement in mental health (p = .004) and social functioning (p = .03) domains of SF-36. Meanwhile, patients treated with embolo-sclerotherapy reported significant improvement only in VAS-P (p = .02). CONCLUSIONS: This study concluded that the effects of care on early follow-up QoL, pain and mental health of patients with CVM were heterogenous. Future research should therefore, include larger sample size and longer term follow-up to understand the various factors that affect the QoL and mental health of these patients, as well as the holistic approaches to manage them.

Efficacy and safety of foam sclerotherapy with sodium tetradecyl sulfate as preferred sclerosant of venous malformations based on experience from a single specialist center.

OBJECTIVE: We have assessed the efficacy and safety of interventional therapy for venous malformations (VMs), with foam sclerotherapy as the treatment of choice according to our experience at a single specialist center. METHODS: All the patients with VMs who had undergone interventional therapy (ie, embolo-sclerotherapy and/or open surgery) from January 1, 2015 to December 31, 2019 were identified through a prospective database. The VM types were classified according to the Puig classification. The outcome measures assessed included the efficacy and complications. The former was divided into four groups: no response, mild response, moderate response, and complete response. The complications were defined as any tissue or functional damage, distal embolization, or tissue reaction. The continuous variables were compared using the analysis of variance F test, and discrete variables were analyzed using the χ2 tests. P values < .05 were considered statistically significant. RESULTS: A total of 207 patients were included. Puig type I lesions were significantly less likely to have received foam sclerotherapy using sodium tetradecyl sulfate (STS) 3% (P ≤ .001) and more likely to have been surgically excised (P ≤ .001). At the patient's first procedure during the study period, the volumes of foam STS 3% were significantly different across all types of VM (P ≤ .001). The patients with type I VMs had received a lower volume of STS 3% compared with those with type II and III VMs. The efficacy outcome categories were significantly different across all types of VMs (P ≤ .001). Overall, only 14 patients (6.8%) had reported no improvement in efficacy, and 38 patients (18%) had not attended follow-up. Therefore, 154 patients (74.8%) had experienced some form of efficacious outcome. Ten patients (4.8%) had developed complications such as hematoma, thrombophlebitis, and ulceration. The incidence of complications differed significantly across the categories (P = .030), with more complications reported for those with type I VMs. CONCLUSIONS: We found that intervention with foam sclerotherapy using STS 3% is clinically effective and safe for patients with VMs and was most successful for those with Puig type I and II VMs.

Use of Aerosolized Prostacyclins in Critically Ill Patients and Association With Clinical Outcomes.

Aerosolized prostacyclins are frequently used in patients with severe acute respiratory distress syndrome and refractory hypoxia. Previous studies have shown improvement in oxygenation with use of pulmonary vasodilators such as iloprost and epoprostenol; however, there is no head-to-head comparison between these agents. OBJECTIVES: To compare the effects of inhaled epoprostenol and inhaled iloprost in critically ill patients with refractory hypoxia. DESIGN SETTING AND PARTICIPANTS: We performed a retrospective cohort analysis of patients admitted to the ICUs at the University of Oklahoma Health Sciences Center between 2015 and 2018. Adult patients who received aerosolized epoprostenol or iloprost for more than 4 hours were included in the analysis. MAIN OUTCOMES AND MEASURES: The primary endpoint measured was to compare the change in Pao2/Fio2 ratio between patients treated with iloprost compared with epoprostenol. Secondary outcomes measured were 90-day in-hospital mortality and improvement in vasopressor requirements. RESULTS: A total of 126 patients were included in the study, 95 of whom received iloprost (75%) and 31 patients (25%) received epoprostenol. There were significant improvements in Pao2/Fio2 ratio in both the iloprost and epoprostenol group. Patients in the epoprostenol group appeared to have a higher 90-day mortality compared with the iloprost group. However, our study was not powered to detect a mortality difference and this finding likely represents a sicker population in the epoprostenol group and prescription bias. The use of iloprost was associated with higher vasopressor requirements in the first 12 hours of administration, an association was not observed in the epoprostenol group. CONCLUSIONS AND RELEVANCE: In this retrospective cohort analysis, use of both pulmonary vasodilators was associated with similar improvement in gas exchange. The mortality difference observed likely represents difference in severity of illness. Further studies are needed to corroborate these findings.

Efficacy and safety of embolo-sclerotherapy of arteriovenous malformations with foam sodium tetradecyl sulphate.

BACKGROUND: To evaluate the efficacy and safety of embolo-sclerotherapy (EST) particularly with foamed sclerotherapy in the treatment of arteriovenous malformations (AVMs). METHODS: All patients with AVM who underwent interventional therapy i.e. EST from January 1st, 2015 - December 31st, 2019 were identified through a prospective database. Types of AVM were classified according to Schobinger's classification. The outcome measures assessed efficacy and complications. The former was divided into four groups: no response, mild response, moderate response, and complete response. Complications were defined as any tissue or functional damage, distal embolization or tissue reaction. Continuous variables were compared using analysis of variance (ANOVA) F test and discrete variables were analysed using χ2 tests. P<0.05 was considered significant. RESULTS: A total of 65 patients were included. There was no statistical difference amongst the volume of foam STS 3% or alcohol used across all types of AVM. Overall, majority of patients (86.2%) reported some degree of improvement following interventional therapy. Six (9.2%) patients experienced complications including necrosis and amputation. The proportions of complication were significantly different across the categories (P=0.009). Patients with type III AVM seemed to report more complications than others. CONCLUSIONS: Foam sclerotherapy was clinically effective and safe for patients with AVM. This study showed that foam sclerotherapy with STS 3% provided a safe and efficacious alternative sclerosant to ethanol despite it was not often reported to be used to treat AVM. However, a combination of embolic agents is likely required to treat type IV AVMs.