BACKGROUND:Neutrophil extracellular traps (NETs) contribute to atherosclerosis progression and are linked to adverse clinical outcomes such as myocardial infarction and stroke. Although the triggers of NET formation in plaques are known, the mechanisms governing DNase-mediated NET clearance and how these are disrupted during atherosclerosis remain unclear. Moreover, the consequences of impaired NET clearance on disease progression are not known. METHODS:Low-density lipoprotein receptor knockout (Ldlr-/-) mice with hematopoietic cell-specific deletion of DNase1 and DNase1L3 were fed a Western-type diet for 16 weeks to examine the impact of loss of DNase activity and the subsequent NET accumulation on advanced atherosclerosis. The effect of NETs on macrophage efferocytosis was examined in vitro and in the mouse peritoneal cavity and atherosclerotic plaque in vivo. To identify the signaling pathway impairing the NET-induced DNase response, in vitro assays were performed using selective endoplasmic reticulum stress pathway inhibitors, and the findings were validated in murine and human atherosclerotic tissues. RESULTS:Lack of DNase secretion by macrophages led to accumulation of NETs in local tissues, including atherosclerotic plaques. Persisting NETs in turn promoted cleavage of the efferocytosis receptor MerTK (c-mer proto-oncogene tyrosine kinase), resulting in defective macrophage efferocytosis and increased atherosclerotic plaque necrosis. In vitro screening identified endoplasmic reticulum stress-induced activation of the PERK (protein kinase R-like endoplasmic reticulum kinase)-ATF (activating transcription factor) 4 signaling axis in atherogenic macrophages as a key driver of impaired DNase secretion, leading to delayed NET clearance and their pathological persistence. Treatment of human atherosclerotic plaques and Ldlr-/- mice with integrated stress response inhibitor, a selective PERK inhibitor, restored vascular DNase secretion and facilitated NET clearance. CONCLUSIONS:Macrophages play a key role in clearing NETs from tissues. Endoplasmic reticulum stress suppresses macrophage DNase secretion, leading to NET accumulation in atherosclerotic plaques, which triggers efferocytosis impairment and plaque progression. Targeting the PERK-ATF4 axis to restore DNase release and NET clearance represents a promising therapeutic strategy to promote plaque stabilization.

Neutrophil extracellular traps (NETs) drive atherosclerosis progression and are associated with adverse clinical outcomes like myocardial infarction and stroke. While the triggers of NETosis in atherosclerotic plaque are well-characterized, the mechanisms underlying NET degradation and clearance remain unclear. Moreover, the impact of impaired NET clearance on atherosclerosis progression have not been elucidated. Here we show that macrophages are critical for the release of DNases, which degrade NETs. We identified endoplasmic reticulum (ER) stress mediated activation of PERK-ATF4 pathway as a key driver of impaired macrophage DNase secretion, leading to delayed NET clearance and their persistence. Elevated NET levels trigger cleavage of the efferocytosis receptor Mertk leading to defective macrophage efferocytosis and exacerbation of plaque necrosis. Human atherosclerotic plaques and Ldlr-/- mice treated with ISRIB, a PERK inhibitor, show enhanced DNase secretion and clearance of NETs. Together, the identification of key mechanisms of NET clearance in atherosclerosis offers new therapeutic strategies to stabilize plaques. ### Competing Interest Statement The authors have declared no competing interest.

ObjectivesBetween the Irish late medieval (AD 1150-c.1550) (LMP) and post-medieval (AD c.1550-1800) (PMP) periods, colonial practices changed land ownership. Contextualizing these periods within a biocultural political economy framework supports increasing social inequality in the PMP, which we expect to be reflected in different skeletal markers of longevity and stress. Therefore, we hypothesized that widespread exposure to stressors and resource deprivation contributed to lower longevity in the PMP compared to the LMP, and that there would be greater variation between sites in the frequency of linear enamel hypoplasias (LEH) in the PMP. Materials and MethodsWe estimated age and counted matched pairs of LEH on 526 adult skeletons from the Irish counties of Dublin, Kildare, Louth, and Meath. Age-at-death was compared through Kaplan-Meier survival functions and non-parametric tests. Linear enamel hypoplasias prevalences were analyzed with Mann-Whitney U tests and Generalized Linear Models. ResultsAge-at-death distribution changed between the LMP and PMP for males, with males experiencing an increase in median-age-at-death. The same was untrue for females, who show no changes in median age-at-death. Analysis of LEH frequency per individual showed that variation between sites was significant in the post-medieval period but not in the late medieval period. ConclusionThese results suggest that social organization contributed to embodied health experiences that varied across time periods. Specifically, populations from the PMP appear to have embodied greater social inequality in their more varied susceptibility to stress. Our work demonstrates the strength of pairing historical texts with the analysis of skeletal remains to evaluate the impact of social structures on biological frailty.

There is growing interest in the roles of temperature, epidermal hydration (EH) and pain in pressure ulcer (PU) development. Investigating correlations between these measures and sub-epidermal moisture (SEM) will address this knowledge deficit. A prospective observational study enrolled 60 surgical patients from February to November 2021. SEM, temperature, EH and pain were assessed using a SEM scanner, thermography imaging, skin hydration device and numeric pain intensity scale, respectively. Measurements were taken at the sacrum, both heels and a control site, before and after surgery for 3 days. Data were analysed using Pearson or Spearman's correlation. Of the participants, 50% were male with a mean age of 58 years (±13.46). Low positive/negative correlations between SEM and temperature were found at the sacrum. However, after removing outliers, these results were not statistically significant. Other sites and follow-up days showed negligible correlations. No evidence of a correlation, to low correlations between SEM and EH were observed, but unreliable due to little variation in EH at the heels. Pain showed negligible correlations with SEM. This study did not find consistent evidence of a correlation between SEM, temperature, EH and pain, highlighting the unreliability of temperature and EH for early PU detection. Post-operative pain may also confound accurate pain assessments.

The correlation between sub-epidermal moisture (SEM) and other early indicators of pressure ulcer (PU) development is yet to be determined. This three-part series aims to bridge this knowledge gap, through investigating SEM and its correlation with evidence-based technologies and assessments. This article focuses on the correlation between SEM and ultrasound. A prospective cohort observational study was undertaken between February and November 2021. Patients undergoing three surgery types were consecutively enrolled to the study following informed consent. Assessments were performed prior to and following surgery for 3 days at the sacrum, both heels and a control site, using a SEM scanner and high-frequency ultrasound scanner (5-15 MHz). Spearman's rank (rs ) explored the correlation between SEM and ultrasound. A total of 60 participants were included; 50% were male with a mean age of 58 years (±13.46). A statistically significant low to moderately positive correlation was observed between SEM and ultrasound across all anatomical sites (rs range = 0.39-0.54, p < 0.05). The only exception was a correlation between SEM and ultrasound on day 0 at the right heel (rs  = 0.23, p = 0.09). These results indicate that SEM and ultrasound agreed in the presence of injury; however, SEM was able to identify abnormalities before ultrasound.

Endograft explantation and conversion to open repair following endovascular aneurysm repair (EVAR) represents a stark reminder of the limitations of EVAR and the endovascular techniques currently available to rescue the failing graft. Editor's Choice – The VASCUNExplanT Project: An International Study Assessing Open Surgical Conversion of Failed Non-Infected Endovascular Aortic Aneurysm RepairEuropean Journal of Vascular and Endovascular SurgeryVol. 66Issue 5PreviewThe need for open surgical conversion (OSC) after failed endovascular aortic aneurysm repair (EVAR) persists, despite expanding endovascular options for secondary intervention. The VASCUNExplanT project collected international data to identify risk factors for failed EVAR, as well as OSC outcomes. This retrospective cross sectional study analysed data after OSC for failed EVAR from the VASCUNET international collaboration. Full-Text PDF

Abstract Background Large-artery ischaemic stroke is associated with a high-risk of recurrence. Inflammation is important in the development and rupture of carotid plaque. It remains unknown if blood-biomarkers can reliably quantify vascular inflammation. We investigated whether blood-biomarkers were associated with recurrent ipsilateral Ischaemic Stroke (IS). Methods hsCRP and IL-6 were measured in blood-samples using immunochemiluminescence immunoassays from three cohort studies. Median follow-up was 3.9 years (IQR 1.6–5.8). The primary outcome was recurrent ipsilateral IS. Results Of 269 participants, 130 (48.3%) had severe CS (median age, 71 (IQR 64–78)). There were 19 ipsilateral recurrent IS in 1,046-patient-years follow-up. hsCRP was dichotomised at 2 mg/L and IL-6 at 7 pg/ml (expected-normal value for assay). 187 (69.5%) had hsCRP<2 mg/L and 170 (63.2%) had IL-6 ≥ 7 pg/ml. 146 (54.3%) participants had combined-raised hsCRP≥2 mg/L and IL-6 ≥ 7 pg/ml. On unadjusted Cox analysis, hsCRP≥2 mg/L was associated with increased risk of ipsilateral recurrent IS (HR 9.25, CI 1.24–69.2, p = 0.03) while IL-6 ≥ 7 pg/ml trended towards increased risk (HR 2.36, CI 0.79–7.1, p = 0.1.) However, combined raised-hsCRP/IL-6 was associated with an increased risk of recurrent ipsilateral IS (HR 3.58, CI 1.2–10.7, p = 0.02.) However, after adjustment for age, sex, smoking and time-to-phlebotomy, these associations attenuated. When patients were divided into three risk categories defined by levels of hsCRP and IL-6 (low [both markers low], intermediate [discordant markers], high [both markers raised]0, the rate of recurrent stroke increased across the categories, p = 0.013 for trend. The c-statistic for combined-raised hsCRP/IL-6 was 0.66 (CI 0.57–0.75) indicating prognostication better than chance to predict recurrent-ipsilateral IS. Conclusion Using blood inflammatory proteins in combination may add value in risk prediction in patients with carotid atherosclerosis, although this concept requires independent replication and validation in larger cohorts.

Objectives: While endovascular intervention is the recommended first option for management of common iliac artery (CIA) lesions, it lacks durable patency for Trans-Atlantic Inter-Society Consensus (TASC)-II C and D lesions involving the external iliac artery (EIA). Aorto-femoral bypass is a durable option but is unsuitable in patients with significant co-morbidities. Eversion endarterectomy provides an alternative to both endovascular and extensive open aortoiliac reconstruction for occlusive EIA disease. Materials and Methods: A single-center, retrospective review (2000-2020) of all patients undergoing eversion endarterectomy for EIA disease was undertaken. Demographic, clinical, operative and follow-up data were recorded. Results: Fifty eversion endarterectomies were performed in 47 patients. The median age was 65.0 years (range 46-82) and 66.6% were male. Sixty-eight percent (n = 34) were ASA grade 3. Indications for intervention were disabling claudication (44%) and critical limb ischaemia (56%). Angiography demonstrated 22 TASC C and 28 TASC D lesions. The median follow-up was 18.5 months (range 0-149). The technical success rate was 100%, and 84% (n = 42) experienced an immediate symptomatic improvement. Primary and primary-assisted patency at one, three and five years was 86%, 82% and 74%, and 100%, 96% and 92%, respectively. The five-year limb salvage rate was 96%. Eight limbs required reintervention to maintain patency, either by open (n = 2), endovascular (n = 3) or hybrid approach (n = 3). Thirty-day mortality was 2% (n = 1) with 10% (n = 5) experiencing a procedure-related morbidity. All-cause mortality was 38% (n = 19) during the follow-up period. Conclusions: Eversion endarterectomy is a safe, effective alternative treatment for occlusive EIA disease. This study reports durable patency at five years and low perioperative morbidity and mortality.

Objective The presence of atherosclerotic plaque components such as lipid rich necrotic core and intraplaque haemorrhage is associated with increased plaque vulnerability, and may be used to stratify the risk of future cerebrovascular events. Our aim was to investigate the relationship between selected carotid plaque components imaged with CTA, patient characteristics, and clinical outcomes. Methods Symptomatic patients underwent carotid CTA as part of the BIOVASC study. Images were analysed for plaque volume composition with a semi-automatic Hounsfield Unit (HU)-based algorithm. Plaque components were classified based on their attenuation values: lipids <61 HU, fibrous tissue 61-129 HU and calcium >131 HU. Parametric and non-parametric tests were performed to compare plaque measurements to clinical characteristics and outcomes. Results One-hundred and two symptomatic carotids were analysed (avg. age 69y, 54.9% Male, 29.4% severe stenosis). Mean plaque volume was 480±230 mm3, and the mean LRNC volume was 170±100 mm3. A difference in LRNC volume was identified between moderate and severe stenosis (190–150 mm3, p=0.012). Regression analysis showed that age and gender may predict increased plaque volume (p<0.001). A trend for reduced mean plaque LRNC was identified in patients receiving statins (130-210 mm3, p=0.08). Intra-reader reliability showed good agreement (0.62-0.78, p<0.001) between CTA plaque measurements. Conclusions In-vivo CTA plaque volume composition assessment is feasible with good intra-reader reliability. Our findings suggest that CTA-HU measurements may be used to provide improved mechanistic and diagnostic insights into atherosclerotic disease, and facilitate the quantification of selected plaque components whose presence may be associated with increased plaque vulnerability. Key Points ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was partially supported by the Health Research Board (Ireland). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study has been granted full institutional, ethical approval by the Mater Misericordiae University Hospital Ethics Committee on the 2 April 2014 as part of the larger BIOVASC study (Reference number: 1/378/1131). All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors * BIOVASC : Biomarkers Imaging Vulnerable Atherosclerosis in Symptomatic Carotid disease CPR : Curved-planar reformation DSA : Digital subtraction angiography ECST : European Carotid Surgery Trial FC : Fibrous cap ICA : Internal carotid artery ICC : Intraclass correlation IPH : Intraplaque haemorrhage LRNC : Lipid rich necrotic core MRS : Modified Rankin scale NASCET : North American Symptomatic Carotid Endarterectomy Trial TIA : Transient ischaemic attack

Background and Objectives In pooled analyses of endarterectomy trials for symptomatic carotid stenosis, several subgroups experienced no net benefit from revascularization. The validated symptomatic carotid atheroma inflammation lumen-stenosis (SCAIL) score includes stenosis severity and inflammation measured by PET and improves the identification of patients with recurrent stroke compared with lumen-stenosis alone. We investigated whether the SCAIL score improves the identification of recurrent stroke in subgroups with uncertain benefit from revascularization in endarterectomy trials. Methods We did an individual-participant data pooled analysis of 3 prospective cohort studies (Dublin Carotid Atherosclerosis Study [DUCASS], 2008-2011; Biomarkers and Imaging of Vulnerable Atherosclerosis in Symptomatic Carotid Artery Disease [BIOVASC], 2014-2018; Barcelona Plaque Study, 2015-2018). Eligible patients had a recent nonsevere (modified Rankin Scale score <= 3) anterior circulation ischemic stroke/TIA and ipsilateral mild carotid stenosis (<50%); ipsilateral moderate carotid stenosis (50%-69%) plus at least 1 of female sex, age <65 years, diabetes mellitus, TIA, or delay >14 days to revascularization; or monocular loss of vision. Patients underwent coregistered carotid F-18-fluorodeoxyglucosePET/CT angiography (<= 7 days from inclusion). The primary outcome was 90-day ipsilateral ischemic stroke. Multivariable Cox regression modeling was performed. Results We included 135 patients. All patients started optimal modern-era medical treatment at admission, and 62 (45.9%) underwent carotid revascularization (36 within the first 14 days and 26 beyond). At 90 days, 18 (13.3%) patients had experienced at least 1 stroke recurrence. The risk of recurrence increased progressively according to the SCAIL score (0.0% in patients scoring 0-1, 15.1% scoring 2-3, and 26.7% scoring 4-5; p = 0.04). The adjusted (age, smoking, hypertension, diabetes, carotid revascularization, antiplatelets and statins) hazard ratio for ipsilateral recurrent stroke per 1-point SCAIL increase was 2.16 (95% CI 1.32-3.53; p = 0.002). A score >= 2 had a sensitivity of 100% for recurrence. Discussion The SCAIL score improved the identification of early recurrent stroke in subgroups who did not experience benefit in endarterectomy trials. Randomized trials are needed to test whether a combined stenosis-inflammation strategy will improve selection for carotid revascularization when benefit is currently uncertain. Classification of Evidence This study provides Class II evidence that, in patients with recent anterior circulation ischemic stroke who do not benefit from carotid revascularization, the SCAIL score accurately distinguishes those at risk for recurrent ipsilateral ischemic stroke.

Background and Objectives To determine whether carotid plaque inflammation identified by 18F-fluorodeoxyglucose (18FDG)-PET is associated with late (5-year) recurrent stroke. Methods We did an individual-participant data pooled analysis of 3 prospective studies with near-identical study methods. Eligible patients had recent nonsevere (modified Rankin Scale score ≤3) ischemic stroke/TIA and ipsilateral carotid stenosis (50%–99%). Participants underwent carotid 18FDG-PET/CT angiography ≤14 days after recruitment. 18FDG uptake was expressed as maximum standardized uptake value (SUVmax) in the axial single hottest slice of symptomatic plaque. We calculated the previously validated Symptomatic Carotid Atheroma Inflammation Lumen-Stenosis (SCAIL) score, which incorporates a measure of stenosis severity and 18FDG uptake. The primary outcome was 5-year recurrent ipsilateral ischemic stroke after PET imaging. Results Of 183 eligible patients, 181 patients completed follow-up (98.9%). The median duration of follow-up was 4.9 years (interquartile range 3.3–6.4 years, cumulative follow-up period 901.8 patient-years). After PET imaging, 17 patients had a recurrent ipsilateral ischemic strokes at 5 years (recurrence rate 9.4%, 95% confidence interval [CI] 5.6%–14.6%). Baseline plaque SUVmax independently predicted 5-year ipsilateral recurrent stroke after adjustment for age, sex, carotid revascularization, stenosis severity, NIH Stroke Scale score, and diabetes mellitus (adjusted hazard ratio [HR] 1.98, 95% CI 1.10–3.56, p = 0.02 per 1–g/mL increase in SUVmax). On multivariable Cox regression, SCAIL score predicted 5-year ipsilateral stroke (adjusted HR 2.73 per 1-point increase, 95% CI 1.52–4.90, p = 0.001). Discussion Plaque inflammation–related 18FDG uptake improved identification of 5-year recurrent ipsilateral ischemic stroke. Addition of plaque inflammation to current selection strategies may target patients most likely to have late and early benefit from carotid revascularization. Classification of Evidence This study provides Class I evidence that in individuals with recent ischemic stroke/TIA and ipsilateral carotid stenosis, carotid plaque inflammation–related 18FDG uptake on PET/CT angiography was associated with 5-year recurrent ipsilateral stroke.

Background: The risk of disabling stroke is highest in the first 14 days after onset of symptoms. Current European Society of Vascular Surgery guidelines recommend that carotid endarterectomy should be performed within 14 days of symptom onset in patients with the appropriate degree of carotid stenosis. We have previously reported difficulty complying with this recommendation. The COVID-19 pandemic has caused severe disruption to all elective and urgent surgical procedures. This study looks at the effect on time to surgery following symptoms in patients requiring carotid endarterectomy.

Background and Purpose— In randomized trials of symptomatic carotid endarterectomy, only modest benefit occurred in patients with moderate stenosis and important subgroups experienced no benefit. Carotid plaque 18 F-fluorodeoxyglucose uptake on positron emission tomography, reflecting inflammation, independently predicts recurrent stroke. We investigated if a risk score combining stenosis and plaque 18 F-fluorodeoxyglucose would improve the identification of early recurrent stroke. Methods— We derived the score in a prospective cohort study of recent (<30 days) non-severe (modified Rankin Scale score ≤3) stroke/transient ischemic attack. We derived the SCAIL (symptomatic carotid atheroma inflammation lumen-stenosis) score (range, 0–5) including 18 F-fluorodeoxyglucose standardized uptake values (SUV max <2 g/mL, 0 points; SUV max 2–2.99 g/mL, 1 point; SUV max 3–3.99 g/mL, 2 points; SUV max ≥4 g/mL, 3 points) and stenosis (<50%, 0 points; 50%–69%, 1 point; ≥70%, 2 points). We validated the score in an independent pooled cohort of 2 studies. In the pooled cohorts, we investigated the SCAIL score to discriminate recurrent stroke after the index stroke/transient ischemic attack, after positron emission tomography-imaging, and in mild or moderate stenosis. Results— In the derivation cohort (109 patients), recurrent stroke risk increased with increasing SCAIL score ( P =0.002, C statistic 0.71 [95% CI, 0.56–0.86]). The adjusted (age, sex, smoking, hypertension, diabetes mellitus, antiplatelets, and statins) hazard ratio per 1-point SCAIL increase was 2.4 (95% CI, 1.2–4.5, P =0.01). Findings were confirmed in the validation cohort (87 patients, adjusted hazard ratio, 2.9 [95% CI, 1.9–5], P <0.001; C statistic 0.77 [95% CI, 0.67–0.87]). The SCAIL score independently predicted recurrent stroke after positron emission tomography-imaging (adjusted hazard ratio, 4.52 [95% CI, 1.58–12.93], P =0.005). Compared with stenosis severity (C statistic, 0.63 [95% CI, 0.46–0.80]), prediction of post-positron emission tomography stroke recurrence was improved with the SCAIL score (C statistic, 0.82 [95% CI, 0.66–0.97], P =0.04). Findings were confirmed in mild or moderate stenosis (adjusted hazard ratio, 2.74 [95% CI, 1.39–5.39], P =0.004). Conclusions— The SCAIL score improved the identification of early recurrent stroke. Randomized trials are needed to test if a combined stenosis-inflammation strategy improves selection for carotid revascularization where benefit is currently uncertain.

Background: Stroke is the leading cause of disability and second leading cause of death globally. Carotid artery stenosis accounts for 10-15% of ischaemic strokes. Carotid endarterectomy (CEA) is a surgical method of stroke risk reduction in patients with high-grade stenosis. Best evidence recommends CEA within 14 days of an acute neurological event in patients with ipsilateral stenosis >70% to confer maximum preventative benefit.

PurposeInflammation is important in stroke. Anti-inflammatory therapy reduces vascular events in coronary patients. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) identifies plaque inflammation-related metabolism. However, long-term prospective cohort studies investigating the association between carotid plaque inflammation, identified on 18F-FDG PET and the risk of recurrent vascular events, have not yet been undertaken in patients with stroke.ParticipantsThe Biomarkers Imaging Vulnerable Atherosclerosis in Symptomatic Carotid disease (BIOVASC) study and Dublin Carotid Atherosclerosis Study (DUCASS) are two prospective multicentred observational cohort studies, employing near-identical methodologies, which recruited 285 patients between 2008 and 2016 with non-severe stroke/transient ischaemic attack and ipsilateral carotid stenosis (50%–99%). Patients underwent coregistered carotid 18F-FDG PET/CT angiography and phlebotomy for measurement of inflammatory cytokines. Plaque 18F-FDG-uptake is expressed as maximum standardised uptake value (SUVmax) and tissue-to-background ratio. The BIOVASC-Late study is a follow-up study (median 7 years) of patients recruited to the DUCASS/BIOVASC cohorts.Findings to dateWe have reported that 18F-FDG-uptake in atherosclerotic plaques of patients with symptomatic carotid stenosis predicts early recurrent stroke, independent of luminal narrowing. The incorporation of 18F-FDG plaque uptake into a clinical prediction model also improves discrimination of early recurrent stroke, when compared with risk stratification by luminal stenosis alone. However, the relationship between 18F-FDG-uptake and late vascular events has not been investigated to date.Future plansThe primary aim of BIOVASC-Late is to investigate the association between SUVmax in symptomatic ‘culprit’ carotid plaque (as a marker of systemic inflammatory atherosclerosis) and the composite outcome of any late major vascular event (recurrent ischaemic stroke, coronary event or vascular death). Secondary aims are to investigate associations between: (1) SUVmax in symptomatic plaque, and individual vascular endpoints (2) SUVmax in asymptomatic contralateral carotid plaque and SUVmax in ipsilateral symptomatic plaque (3) SUVmax in asymptomatic carotid plaque and major vascular events (4) inflammatory cytokines and vascular events.

Background: Blood products are essential for safe surgery, however, the over-ordering of blood for elective procedures wastes hospital resources. A Maximum Surgical Blood Ordering Schedule (MSBOS) guides preoperative orders, improving efficiency and reducing costs. As surgical techniques change, so can the need for intraoperative transfusion. Regular MSBOS audit is needed to ensure transfusion guidelines reflect surgical practice. Methods: Retrospective audit of preoperative blood orders and intraoperative usage in peripheral bypass surgery. Data was collected from theatre logbooks and transfusion laboratory records. Standard was the Mater Misericordiae University Hospital (MMUH) MSBOS: 2 units for femoral-distal bypass (FDB) and type & screen for femoral-popliteal bypass (FPB). Results: Over 10 months, 13 patients had FDB and 21 had FPB (n=34). All had preoperative blood testing; 7 patients (20%) received intraoperative blood, 5 during an FBD and 2 during an FPB. A total of 49 units were available in theatre, and 82% were returned unused. The total crossmatch-transfusion ratio (CTR) was 5.444:1. MSBOS compliance was 92% for FDB, with a CTR of 4.16:1; 12 of 13 patients had units available, and 76% were returned unused. MSBOS compliance was 52% for FPB, with a CTR of 8:1; 10 of 21 patients had units available, and 87.5% were returned unused. Conclusions: MSBOS compliance and overall transfusion requirements were higher for FDB, a more extensive surgery, compared to FPB. The data suggests current MSBOS guidelines for FPB reflect intraoperative transfusion requirements, and that preoperative requests are excessive. For FDB, it should be considered that current MSBOS recommendations may exceed intraoperative requirements.