Association of epicardial adipose tissue with early structural and functional cardiac changes in Type 2 diabetes

BACKGROUND

Dysregulated epicardial adipose tissue (EAT) may contribute to the development of heart failure in Type 2 diabetes (T2D). This study aimed to evaluate the associations between EAT volume and composition with imaging markers of subclinical cardiac dysfunction in people with T2D and no prevalent cardiovascular disease.

METHODS

Prospective case-control study enrolling participants with and without T2D and no known cardiovascular disease. Two hundred and fifteen people with T2D (median age 63 years, 60 % male) and thirty-nine non-diabetics (median age 59 years, 62 % male) were included. Using computed tomography (CT), total EAT volume and mean CT attenuation, as well as, low attenuation (Hounsfield unit range -190 to -90) EAT volume were quantified by a deep learning method and volumes indexed to body surface area. Associations with cardiac magnetic resonance-derived left ventricular (LV) volumes and strain indices were assessed using linear regression.

RESULTS

T2D participants had higher LV mass/volume ratio (median 0.89 g/mL [0.82-0.99] vs 0.79 g/mL [0.75-0.89]) and lower global longitudinal strain (GLS; 16.1 ± 2.3 % vs 17.2 ± 2.2 %). Total indexed EAT volume correlated inversely with mean CT attenuation. Low attenuation indexed EAT volume was 2-fold higher (18.8 cm3/m2 vs. 9.4 cm3/m2, p < 0.001) in T2D and independently associated with LV mass/volume ratio (ß = 0.002, p = 0.01) and GLS (ß = -0.03, p = 0.03).

CONCLUSIONS

Higher EAT volumes seen in T2D are associated with a lower mean CT attenuation. Low attenuation indexed EAT volume is independently, but only weakly, associated with markers of subclinical cardiac dysfunction in T2D.

Stimulated Raman Histology Interpretation by Artificial Intelligence Provides Near-Real-Time Pathologic Feedback for Unprocessed Prostate Biopsies

PURPOSE

Stimulated Raman histology is an innovative technology that generates real-time, high-resolution microscopic images of unprocessed tissue, significantly reducing prostate biopsy interpretation time. This study aims to evaluate the ability for an artificial intelligence convolutional neural network to interpretate prostate biopsy histologic images created with stimulated Raman histology.

MATERIALS AND METHODS

Unprocessed, unlabeled prostate biopsies were prospectively imaged using a stimulated Raman histology microscope. Following stimulated Raman histology creation, the cores underwent standard pathological processing and interpretation by at least 2 genitourinary pathologists to establish a ground truth assessment. A network, trained on 303 prostate biopsies from 100 participants, was used to measure the accuracy, sensitivity, and specificity of detecting prostate cancer on stimulated Raman histology relative to conventional pathology. The performance of the artificial intelligence was evaluated on an independent 113-biopsy test set.

RESULTS

Prostate biopsy images obtained through stimulated Raman histology can be generated within a time frame of 2 to 2.75 minutes. The artificial intelligence system achieved a rapid classification of prostate biopsies with cancer, with a potential identification time of approximately 1 minute. The artificial intelligence demonstrated an impressive accuracy of 96.5% in detecting prostate cancer. Moreover, the artificial intelligence exhibited a sensitivity of 96.3% and a specificity of 96.6%.

CONCLUSIONS

Stimulated Raman histology generates microscopic images capable of accurately identifying prostate cancer in real time, without the need for sectioning or tissue processing. These images can be interpreted by artificial intelligence, providing physicians with near-real-time pathological feedback during the diagnosis or treatment of prostate cancer.

Analysis of Adeno-Associated Virus Serotype 8 (AAV8)-antibody complexes using epitope mapping by molecular imprinting leads to the identification of Fab peptides that potentially evade AAV8 neutralisation

Gene therapy is a promising approach for treating genetic disorders by delivering therapeutic genes to replace or correct malfunctioning genes. However, the introduced gene therapy vector can trigger an immune response, leading to reduced efficacy and potential harm to the patient. To improve the efficiency and safety of gene therapy, preventing the immune response to the vector is crucial. This can be achieved through the use of immunosuppressive drugs, vector engineering to evade the immune system, or delivery methods that bypass the immune system altogether. By reducing the immune response, gene therapy can deliver therapeutic genes more effectively and potentially cure genetic diseases. In this study, a novel molecular imprinting technique, combined with mass-spectrometry and bioinformatics, was used to identify four antigen-binding fragments (Fab) sequences of Adeno-Associated Virus (AAV) - neutralising antibodies capable of binding to AAV. The identified Fab peptides were shown to prevent AAV8's binding to antibodies, demonstrating their potential to improve gene therapy efficiency by preventing the immune response.

Potential role for extracorporeal membrane oxygenation cardiopulmonary resuscitation (E-CPR) during in-hospital cardiac arrest in Australia: A nested cohort study

Objective

This study aims to evaluate the characteristics and outcomes of patients who fulfilled extracorporeal membrane oxygenation cardiopulmonary resuscitation (E-CPR) selection criteria during in-hospital cardiac arrest (IHCA).

Design

This is a nested cohort study.

Setting

Code blue data were collected across seven hospitals in Australia between July 2017 and August 2018.

Participants

Participants who fulfilled E-CPR selection criteria during IHCA were included.

Main outcome measures

Return of spontaneous circulation and survival and functional outcome at hospital discharge. Functional outcome was measured using the modified Rankin scale, with scores dichotomised into good and poor functional outcome.

Results

Twenty-three (23/144; 16%) patients fulfilled E-CPR selection criteria during IHCA, and 11/23 (47.8%) had a poor outcome. Patients with a poor outcome were more likely to have a non-shockable rhythm (81.8% vs. 16.7%; p = 0.002), and a longer duration of CPR (median 12.5 [5.5, 39.5] vs. 1.5 [0.3, 2.5] minutes; p < 0.001) compared to those with a good outcome. The majority of patients (18/19 [94.7%]) achieved sustained return of spontaneous circulation within 15 minutes of CPR. All five patients who had CPR >15 minutes had a poor outcome.

Conclusion

Approximately one in six IHCA patients fulfilled E-CPR selection criteria during IHCA, half of whom had a poor outcome. Non-shockable rhythm and longer duration of CPR were associated with poor outcome. Patients who had CPR for >15 minutes and a poor outcome may have benefited from E-CPR. The feasibility, effectiveness and risks of commencing E-CPR earlier in IHCA and among those with non-shockable rhythms requires further investigation.

Improved Measurement of the Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

Precision Measurement of Reactor Antineutrino Oscillation at Kilometer-Scale Baselines by Daya Bay

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

Portfolios in practice: Developing advancing practice within a musculoskeletal competency-based model

INTRODUCTION

The development of professional portfolios and the relevance of this within professional practice, competency and capability is gaining significant credibility in line with professional requirements. Nursing and medicine in terms of historical perspectives have long held the need for clinicians to maintain a portfolio for professional validation, whilst in other professional groups it is a requirement of registration. The allied health professionals, physiotherapy and ultimately musculoskeletal practice within this context are rapidly developing advancing and consultant practice. This professional development further requires appropriate verification and validation of practice, and achieving this can be through formal and non-formal routes.

PURPOSE

This paper looks to explore this and give direction to professionals developing portfolios whilst placing the requirements in context to contemporary practice in the U.K. Universities, professional bodies and special interest groups are now aligning in the need to support practice in a multi-format way, that moves away from traditional methods of evaluation into more diverse models of competency-based assessment.

IMPLICATIONS

With improvement in technology, the development of national frameworks and standards, portfolios in practice although commonly considered as standard practice will be a requirement not only of registration but as a criteria of maintaining status, career development and expansion of roles.

BACKGROUND

Musculoskeletal (MSK) physiotherapy in the U.K. has moved forward significantly in the last 20 years. Sitting within a clinical reasoned framework, the introduction of additional skills such is image requesting, injection therapies, and non-medical prescribing has further underpinned the advanced practice agenda (Langridge et al., 2015). While these advancements in practice are driving the profession forward, challenges remain in providing the workforce with a clear process of career development. Alongside developing professional pathways methods of evidencing advanced knowledge and skills acquired outside formal routes are required to support practitioners' career pathway into advancing practice.

Cov2MS: An Automated and Quantitative Matrix-Independent Assay for Mass Spectrometric Measurement of SARS-CoV-2 Nucleocapsid Protein

The pandemic readiness toolbox needs to be extended, targeting different biomolecules, using orthogonal experimental set-ups. Here, we build on our Cov-MS effort using LC-MS, adding SISCAPA technology to enrich proteotypic peptides of the SARS-CoV-2 nucleocapsid (N) protein from trypsin-digested patient samples. The Cov²MS assay is compatible with most matrices including nasopharyngeal swabs, saliva, and plasma and has increased sensitivity into the attomole range, a 1000-fold improvement compared to direct detection in a matrix. A strong positive correlation was observed with qPCR detection beyond a quantification cycle of 30-31, the level where no live virus can be cultured. The automatable sample preparation and reduced LC dependency allow analysis of up to 500 samples per day per instrument. Importantly, peptide enrichment allows detection of the N protein in pooled samples without sensitivity loss. Easily multiplexed, we detect variants and propose targets for Influenza A and B detection. Thus, the Cov²MS assay can be adapted to test for many different pathogens in pooled samples, providing longitudinal epidemiological monitoring of large numbers of pathogens within a population as an early warning system.

Low dose rivaroxaban therapy in aspirin allergic patients undergoing percutaneous coronary intervention

 

Aspirin in combination with a P2Y12 inhibitor is the mainstay of treatment post percutaneous coronary intervention (PCI) for coronary artery disease (CAD). However, patients who are allergic to or intolerant to aspirin pose a therapeutic challenge especially when encountered in the setting of acute coronary syndrome. Aspirin desensitization strategies have been used in clinical practice to build tolerance prior to coronary intervention but clearly are not practical in the setting of ACS or significant symptomatic CAD. Low dose rivaroxaban (2.5 mg twice a day) has been previously shown to be safe in combination with a P2Y12 inhibitor post ACS compared to aspirin. We therefore sought to see if low dose rivaroxaban is a safe and effective alternative to aspirin in patients post PCI who are unable to take aspirin.This study aims to compare the efficacy (Major adverse cardiovascular events (MACE)) and safety (Bleeding events as defined by Bleeding Academic Research Consortium (BARC) criteria) in patients with confirmed aspirin allergy who were treated with low dose rivaroxaban therapy in place of aspirin in combination with P2Y12 inhibitors post PCI.

Methods

This was a single center observational study which looked at 50 cases of patients with aspirin allergy (47 cases) or significant confirmed aspirin intolerance (3 cases) who underwent PCI between December 2017 and February 2022. Patients were advised to take low dose rivaroxaban 2.5 mg twice a day as an alternative to aspirin 75 mg once a day. A comparator group of 50 matched patients without aspirin allergy who underwent PCI during the same time period and treated with standard aspirin therapy (75mg) along with a P2Y12 inhibitor. Outcomes over follow-up were MACE (mortality, myocardial infarction, stroke, and unscheduled revascularisation) and bleeding events defined by–BARC criteria.

Results

The median age of the aspirin allergy cohort was 62 years old with typical comorbidities associated with CAD. The cohort included a case mix of ACS and stable angina.The P2Y12 inhibitor in the majority of cases (76%) was Clopidogrel; Ticagrelor was used in 20% of cases and Prasugrel in 4% cases. No differences existed between the rivaroxaban and matched patient groups. The median follow-up as 626 days (Interquartile range 237–549). The duration of low dose rivaroxaban therapy was for 12 months with a P2Y12 in 72%, 1–3 months for 22% and finally continued long term (with P2Y12 discontinuation at 12 months) in 6%. No difference existed in the incidence of MACE between the low dose rivaroxaban group (12%) compared to the matched cohort (10% p=0.266). No difference in bleeding outcomes (any bleeding event BARC type &gt;0) were seen (14% in rivaroxaban and 16% in control, p=0.329).

Conclusions

This study provides more supporting evidence that low dose rivaroxaban therapy is an alternative to aspirin when used in combination with a P2Y12 inhibitor post PCI.

Funding Acknowledgement

Type of funding sources: None.

Prevalence and impact of TWILIGHT criteria in all-comer patients undergoing percutaneous coronary intervention

Background

The Ticagrelor with Aspirin or Alone in High-Risk Patients after Coronary Intervention (TWILIGHT) randomized clinical trial demonstrated that in selected high risk patients who took ticagrelor and aspirin for 3 months after percutaneous coronary intervention (PCI), continuing ticagrelor alone was associated with significantly less bleeding events than ticagrelor plus aspirin and did not lead to ischemic harm over a period of 1 year (1).

The prevalence and risk of adverse events of patients fulfilling the TWILIGHT inclusion criteria in real-world setting is unclear.

Purpose

To elucidate the prevalence and prognosis of patients fulfilling the TWILIGHT inclusion criteria.

Methods

Patients that received at least one drug eluting stent in a coronary artery at a large tertiary center (Mount Sinai Hospital, New York) were considered for inclusion. As in the TWILIGHT trial, individuals on chronic oral anticoagulation treatment, with STEMI, cardiogenic shock, on dialysis, with prior stroke, or platelet count &lt;100,000 were excluded. Patients were stratified in two groups: 1) TWILIGHT-like patients, who met at least one clinical (age ≥65 years, female sex, established vascular disease, diabetes mellitus, estimated glomerular fraction rate &lt;60mL/min, acute coronary syndrome with troponin increase) and one angiographic (multivessel coronary artery disease [CAD], stent length &gt;30mm, thrombotic target lesion, bifurcation requiring 2 stents, left main or proximal left anterior descending artery lesion, atherectomy device use, SYNTAX score ≥23) TWILIGHT inclusion criterion; 2) Non-TWILIGHT-like patients, who did not fulfil at least one clinical and one angiographic TWILIGHT inclusion criterion.

The primary outcome was a composite of death, myocardial infarction (MI), stroke. Secondary outcomes included bleeding, components of the primary outcome, target vessel and target lesion revascularization, stent thrombosis. All events were assessed at 1 year after PCI.

Results

Out of 30,470 patients undergoing PCI between 2012 and 2019, 13,236 were included in the current analysis. TWILIGHT criteria were met in 11,018 (83%) patients. Established vascular disease and multivessel CAD were the most frequently fulfilled criteria. At 1 year, TWILIGHT-like patients were at higher risk for the primary outcome (3.2% vs 1.1%, HR 2.85, 95% CI 1.83–4.44), severe bleeding (3.3% vs 1.8%, HR 1.86, 95% CI 1.32–2.62), all-cause death (1.4% vs 0.4%, HR 3.63, 95% CI 1.70–7.77), myocardial infarction (1.8% vs 0.6%, HR 2.81 95% CI 1.56–5.04), TVR (7.8% vs 4.1%, HR 1.94, 95% CI 1.53–2.47), TLR (5.1% vs 1.7%, HR 2.98 95% CI 2.07–4.29). Stent thrombosis and stroke rate were generally low and did not differ between patients meeting or not the TWILIGHT inclusion criteria.

Conclusion

Among all-comer patients undergoing PCI, the fulfillment of the TWILIGHT inclusion criteria is frequent and is associated with a higher risk of death, ischemic and bleeding complications

Funding Acknowledgement

Type of funding sources: None.

Comparison of thrombus burden in patients with COVID-19 presenting with ST-segment elevation myocardial infarction across the three waves of outbreak in the United Kingdom

Background

It has been previously reported during the first COVID outbreak that patients presenting with ST-Segment Elevation Myocardial Infarction (STEMI) and concurrent COVID-19 infection have increased thrombus burden and poorer outcomes [1]. Subsequently, there have been multiple further waves of the pandemic with the emergence of at least two new COVID-19 variants and the emergence of vaccinations. To-date, there have been no reports comparing the outcomes of COVID-19-positive STEMI patients across all waves of the pandemic.

Purpose

The purpose of this study was to compare the baseline demographic, procedural and angiographic characteristics alongside the clinical outcomes of patients presenting with STEMI and concurrent COVID-19 infection across the COVID-19 pandemic in the UK.

Methods

This was a single-centre, observational study of 1250 consecutive patients admitted with confirmed STEMI treated with primary percutaneous coronary intervention (PCI) at Barts Heart Centre between 01/03/2020 and 10/03/2022. COVID +ve patients were split into 3 groups based upon the time course of the pandemic (Wave 1: March 2020-June 2020, Wave 2: Sept 2020-March 2021, Wave 3: October 2021-March 2022). Comparison was made between waves and with a control group of COVID-ve patients treated during the same timeframe.

Results

A total of 135 COVID +ive patients with STEMI (1st Wave: 39 patients, 2nd Wave: 60 patients, 3rd wave 35 pts) were included in the present analysis; and compared with 1115 COVID negative patients. Significant changes in the baseline characteristics, angiographic features and clinical outcomes of COVID +ive patients occurred over time. Early during the pandemic (Wave 1 2020), STEMI patients presenting with concurrent COVID-19 infection had high rates of cardiac arrest, evidence of increased thrombus burden (higher rates of multi-vessel thrombosis, stent thrombosis, higher modified thrombus grade higher use of GP IIb/IIIa inhibitors and thrombus aspiration, coagulability (more heparin for therapeutic ACT), bigger infarcts (lower myocardial blush grade and left ventricular function) and worse outcomes (mortality). However, by wave 3 (late 2021/2022), no differences existed in clinical characteristics, thrombus burden, infarct size or outcomes between COVID +ive patients and those without concurrent COVID-19 infection with significant differences compared to earlier COVID +ve patients. Poor outcomes later in the study period were predominantly in unvaccinated individuals.

Conclusions

Significant changes have occurred in the clinical characteristics, angiographic features and outcomes of STEMI patients with COVID-19 infection treated by primary PCI during the course of the pandemic. Importantly it appears that angiographic features and outcomes of recent waves are no different to a non-COVID-19 population.

Funding Acknowledgement

Type of funding sources: None.

Impact of body mass index on outcomes in patients undergoing percutaneous coronary intervention for in-stent restenosis

Background

Recent advances in drug eluting stents (DES) design have significantly decreased the rates of in-stent restenosis (ISR). Nonetheless, ISR remains a major problem, affecting 5–10% of patients undergoing percutaneous coronary intervention (PCI). Furthermore, PCI for ISR is often a poor prognostic factor for outcomes after the procedure. Historically, obese patients tended to have better outcomes when undergoing PCI, however it is unclear if this trend continues for the same population undergoing PCI for ISR.

Purpose

Investigate the outcomes of patients undergoing PCI for ISR in the overweight and normal weight population.

Methods

All patients undergoing PCI with DES implantation at a tertiary care center from January 2012 to December 2019 were included. Normal weight was defined as a body mass index (BMI) greater than or equal to 18.5 kg/m2 and less than 25 kg/m2, while overweight was defined as a BMI greater than or equal to 25 kg/m2. Patients with BMI &lt;18.5 kg/m2, underwent PCI for acute myocardial infarction (MI), or received a bare metal stent (BMS) were excluded. The primary outcome was major events (MACE), a composite of all-cause mortality, myocardial infarction (MI), and target vessel revascularization (TVR) up to one year after PCI. Secondary outcomes included individual components of the primary endpoint.

Results

Out of 16,234 patients with available data on BMI, 12,444 (76.7%) were overweight and 3,790 (23.3%) were normal weight. Among overweight patients, 2,879 (23.1%) underwent PCI for ISR versus 815 (21.5%) of normal weight patients. Regardless of BMI status, patients undergoing PCI for ISR had higher rates of co-morbidities such as hypertension, hyperlipidemia, and diabetes mellitus than non-ISR counterparts. At one year post PCI, both overweight and normal weight patients undergoing PCI for ISR had increased risk of MACE (overweight: 18.4% vs. 6.7%; HR 2.83; 95% CI 2.50–3.20; normal weight: 18.8% vs. 7.8%, HR 2.43, 95% CI 1.95–3.04) when compared to non-ISR counterparts, mostly driven by TVR (overweight: 16% vs. 4.6%; HR 3.58; 95% CI 3.11–4.13; normal weight: 15.2% vs. 4.1%; HR 3.69; 95% CI 2.80–4.86). However, only overweight patients undergoing PCI for ISR had higher risk of all cause mortality (2.2% vs. 1.5%; HR 1.42; 95% CI 1.03–1.95) and MI (3.0% vs. 1.3%, HR 2.22; 95% CI 1.64–2.99) when compared to non-ISR counterparts (Figure 1).

Conclusions

PCI for ISR was associated with increased risk of MACE, irrespective of body weight. The risks of all-cause mortality and MI in ISR vs non-ISR patients only reached statistical significance in overweight patients.

Funding Acknowledgement

Type of funding sources: None.

Direct oral anticoagulants compared to vitamin K antagonists for the treatment of left ventricular thrombi

Background

Left ventricular thrombus (LVT) complicates around one in six cases of acute and chronic left ventricular systolic dysfunction and is associated with an increased risk of stroke, major systemic embolism and death, believed to be ameliorated by anticoagulation. Off-label use of direct oral anticoagulants (DOACs) for LVT has steadily increased, largely based on favourable outcomes in atrial fibrillation and venous thromboembolism, but the safety and efficacy of DOACs versus vitamin K antagonists (VKA) for LVT remains uncertain.

Purpose

The main aim of our study was to compare treatment of LVT with VKA to DOAC, focusing on all-cause mortality, stroke, major systemic emboli and major bleeding.

Methods

We conducted a retrospective observational longitudinal study of patients presenting to two large quaternary centres between 2011 and 2021 with a diagnosis of LVT. Patients were eligible if they had a documented LVT and received anticoagulation with either VKA or DOAC. Baseline data, thrombus characteristics, treatment type and duration, follow up imaging and clinical events were recorded using electronic health care records. Outcome measures included thrombus resolution, stroke and systemic embolism (SSE), major bleeding and mortality.

Results

A total of 955 patients were identified, of whom 901 received treatment with either a VKA (567 pts, 62.9%) or a DOAC (334 pts, 37.1%) and were included in the analysis. Underlying aetiologies included acute myocardial infarction (AMI) (38.3%), chronic ischaemic cardiomyopathy (38.0%) and non-ischaemic cardiomyopathy (23.7%). Rivaroxaban (43.4%) was the most frequently prescribed DOAC followed by apixaban (35.9%), and the remaining on edoxaban (20.7%). AMI related LVT was more commonly treated with DOAC (53.0%) and chronic ischaemic cardiomyopathy with VKA (72.9%).

There was a lower baseline LVEF in the VKA cohort (29.5±13.2 vs 33.1±14.2, p&lt;0.0001). Other demographic features were comparable. Median follow up was 2.5 years (IQR: 1–3.5). There were no differences in follow up duration between the two treatments (p=0.17). Greater rates of thrombus resolution were seen in the DOAC group compared to VKA (1 year: 78.4% vs 51.4%, p&lt;0.0001), with higher rates of persistent thrombus over the follow-up period seen in the VKA group (25.1% vs 12.9%, p&lt;0.0001). Rates of stroke and systemic embolization were similar between the groups (VKA 9.3% vs 9.6% DOAC, p=0.93). Higher rates of bleeding (BARC &gt;3, 8.1% VKA, 3.6% DOAC, p=0.031) (Figure 1A) and mortality (VKA 18.5%, DOAC 10.2%, p=0.001) (Figure 1B) were seen in the VKA group over the follow-up period.

Conclusions

In a large multi-centre registry of LVT of mixed aetiology, anticoagulation with DOAC was associated with earlier and greater rates of thrombus resolution and consequential reduced adverse events (major bleeding and mortality) during follow up. A funding application to support a multi-centre randomised control trial is underway.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): This work was supported by the British Heart Foundation (Fellowship FS/CRTF/21/24190 to HM) and the National Institute for Health Research (Biomedical Research Centre Award to Guy's and St Thomas' NHS FT and King's College London).

Incisional hernia following colorectal cancer surgery according to suture technique: Hughes Abdominal Repair Randomized Trial (HART)

BACKGROUND

Incisional hernias cause morbidity and may require further surgery. HART (Hughes Abdominal Repair Trial) assessed the effect of an alternative suture method on the incidence of incisional hernia following colorectal cancer surgery.

METHODS

A pragmatic multicentre single-blind RCT allocated patients undergoing midline incision for colorectal cancer to either Hughes closure (double far-near-near-far sutures of 1 nylon suture at 2-cm intervals along the fascia combined with conventional mass closure) or the surgeon's standard closure. The primary outcome was the incidence of incisional hernia at 1 year assessed by clinical examination. An intention-to-treat analysis was performed.

RESULTS

Between August 2014 and February 2018, 802 patients were randomized to either Hughes closure (401) or the standard mass closure group (401). At 1 year after surgery, 672 patients (83.7 per cent) were included in the primary outcome analysis; 50 of 339 patients (14.8 per cent) in the Hughes group and 57 of 333 (17.1 per cent) in the standard closure group had incisional hernia (OR 0.84, 95 per cent c.i. 0.55 to 1.27; P = 0.402). At 2 years, 78 patients (28.7 per cent) in the Hughes repair group and 84 (31.8 per cent) in the standard closure group had incisional hernia (OR 0.86, 0.59 to 1.25; P = 0.429). Adverse events were similar in the two groups, apart from the rate of surgical-site infection, which was higher in the Hughes group (13.2 versus 7.7 per cent; OR 1.82, 1.14 to 2.91; P = 0.011).

CONCLUSION

The incidence of incisional hernia after colorectal cancer surgery is high. There was no statistical difference in incidence between Hughes closure and mass closure at 1 or 2 years.

REGISTRATION NUMBER

ISRCTN25616490 (http://www.controlled-trials.com).

JS04.6.A The landscape of tumor cell states and spatial organization in H3-K27M mutant diffuse midline glioma across age and location

Background

Histone 3 lysine27-to-methionine mutations (H3-K27M) frequently occur in childhood diffuse midline gliomas (DMGs) of the pons, thalamus and spinal cord, presumed to be driven by the specific spatiotemporal context of these midline locations during postnatal development. While most common in the pons and at mid-childhood ages, the same oncohistone mutation is recurrently detected in adult DMGs and throughout different midline regions. The potential heterogeneity of tumors at different ages and in different anatomical locations of the midline are vastly understudied.

Material and Methods

Through dissecting the transcriptomic, epigenomic and spatial architectures of a comprehensive cohort of patient H3-K27M DMGs - spanning the age range from 2-68 years and locations from spinal cord to thalamus - at single cell resolution, we delineate how age- and location-dependent contexts shape glioma cell-intrinsic and -extrinsic features in light of the shared driver mutation.

Results

We identify that oligodendrocyte precursor (OPC)-like cells constitute the stem-like compartment in H3-K27M DMGs across all clinico-anatomical groups, however, depending on location, display varying levels of maturity resembling less differentiated pre-OPCs or more mature OPCs further differentiated along the oligodendroglial lineage. We further demonstrate increased mesenchymal cell states in adult tumors, which we link to age-related differences in glioma-associated immune cell compartments. We for the first time resolve the spatial organization of H3-K27M DMG cell types in intact patient tissues, identifying a local niche of the oligodendroglial lineage.

Conclusion

Our study provides a powerful resource for rational modeling and therapeutic frameworks taking into account determinants of age and location in this lethal glioma group.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

First Measurement of High-Energy Reactor Antineutrinos at Daya Bay

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{β} isotopes in commercial reactors.

Sampling, storage and laboratory approaches for dissolved organic matter characterisation in freshwaters: Moving from nutrient fraction to molecular-scale characterisation

Recent research has highlighted the importance of dissolved organic matter (DOM) for ecosystem function and because of this paradigm shift, it has become crucial to not only quantify its contribution to river nutrient loads but also to characterise its composition. There has been a significant research effort utilising optical methods, such as fluorescence and UV-Vis spectrophotometry, in order to start exploring DOM character. However, these methods still lack the granularity to understand the chemical composition at the molecular level, which is vital to properly understanding its functional role in freshwater ecosystems. As a direct result, there has been a shift towards including molecular-scale analyses to investigate the in-stream processing of the material. Alongside this, recent methodological advancements, particularly in mass spectrometry are opening new opportunities for probing one of the most complex environmental mixtures. However, in order to fully exploit these opportunities, it is key that the way that samples are collected, processed and stored is considered carefully such that sample integrity is maintained. There are additional challenges when collecting water samples for analysis at molecular scale, for example the ultra-low concentrations of individual compounds within DOM means that the samples are sensitive to contamination. This paper discusses current sample collection, processing and storage protocols for this C, N and P quantification and characterisation in freshwaters, and proposes a new standardised protocol suitable for both nutrient fraction quantification and molecular scale analyses, based on method development and testing undertaken in our UK Natural Environment Research Council large grant programme, characterising the nature, origins and ecological significance of Dissolved Organic Matter IN freshwater Ecosystems (DOMAINE).

FLASH irradiation induces lower levels of DNA damage ex vivo, an effect modulated by oxygen tension, dose, and dose rate

OBJECTIVE

FLASH irradiation reportedly produces less normal tissue toxicity, while maintaining tumour response. To investigate oxygen's role in the 'FLASH effect', we assessed DNA damage levels following irradiation at different oxygen tensions, doses and dose rates.

METHODS

Samples of whole blood were irradiated (20 Gy) at various oxygen tensions (0.25-21%) with 6 MeV electrons at dose rates of either 2 kGy/s (FLASH) or 0.1 Gy/s (CONV), and subsequently with various doses (0-40 Gy) and intermediate dose rates (0.3-1000 Gy/s). DNA damage of peripheral blood lymphocytes (PBL) were assessed by the alkaline comet assay.

RESULTS

Following 20 Gy irradiation, lower levels of DNA damage were induced for FLASH, the difference being significant at 0.25% (p < 0.05) and 0.5% O2 (p < 0.01). The differential in DNA damage at 0.5% O2 was found to increase with total dose and dose rate, becoming significant for doses ≥20 Gy and dose rates ≥30 Gy/s.

CONCLUSION

This study shows, using the alkaline comet assay, that lower levels of DNA damage are induced following FLASH irradiation, an effect that is modulated by the oxygen tension, and increases with the total dose and dose rate of irradiation, indicating that an oxygen related mechanism, e.g. transient radiation-induced oxygen depletion, may contribute to the tissue sparing effect of FLASH irradiation.

ADVANCES IN KNOWLEDGE

This paper is first to directly show that FLASH-induced DNA damage is modulated by oxygen tension, total dose and dose rate, with FLASH inducing significantly lower levels of DNA damage for doses ≥20 Gy and dose rates ≥30 Gy/s, at 0.5% O2.

Head and Neck Merkel Cell Carcinoma: A 12-Year Single Institutional Experience

Background

Merkel cell carcinoma (MCC) is an aggressive malignancy of presumed neuroendocrine origin. Most case series of MCC are limited by low case numbers and are not specific to head and neck tumours. The purpose of this study was to provide a focused review of head and neck MCC diagnosis and management in a single Irish institution.

Methods

Patient's demographics, tumour characteristics, pathological diagnosis, surgical treatment, adjuvant treatment, subsequent management and clinical course were collected. Estimates of progression-free MCC survival rates were calculated by the Kaplan–Meier statistical model. A Pearson product-moment correlation coefficient examined the association between surgical margins and disease-free follow-up.

Results

In total, 11 patients were treated for head and neck MCC with a mean age of 79.6 years (range = 69–91 years). The mean average follow-up duration of patients was 18.3 months. Of the cohort, 18% (n=2) had a sentinel node biopsy (SLNB). A selective neck dissection was subsequently performed in 18% (n=2). In total, 72% (n=8) of patients received adjuvant radiotherapy. Median disease-specific survival was 15 months for the SLNB group and 17 months for the non-SLNB group, not statistically significant (p=0.23). There was no significant association between surgical margins and disease-free follow (p=0.65).

Conclusions

Our case series adds to a limited body of evidence of head and neck MCC. Surgery remains the treatment priority in localized disease, with an increasing role of SLNB for accurate prognostication and staging. Early management of stage I disease results in moderate long-term disease-free survivability.

Systematic review of response criteria and endpoints in autoimmune hepatitis by the International Autoimmune Hepatitis Group

BACKGROUND & AIMS

Autoimmune hepatitis (AIH) has been well characterised and codified through the development of diagnostic criteria. These criteria have been adapted and simplified and are widely used in clinical practice. However, there is a need to update and precisely define the criteria for both treatment response and treatment.

METHODS

A systematic review was performed and a modified Delphi consensus process was used to identify and redefine the response criteria in autoimmune hepatitis.

RESULTS

The consensus process initiated by the International Autoimmune Hepatitis Group proposes that the term 'complete biochemical response' defined as 'normalization of serum transaminases and IgG below the upper limit of normal' be adopted to include a time point at 6 months after initiation of treatment. An insufficient response by 6 months was a failure to meet the above definition. Non-response was defined as '<50% decrease of serum transaminases within 4 weeks after initiation of treatment'. Remission is defined as liver histology with a Hepatitis Activity Index <4/18. Intolerance to treatment was agreed to stand for 'any adverse event possibly related to treatment leading to potential drug discontinuation'.

CONCLUSIONS

These definitions provide a simple and reproducible framework to define treatment response and non-response, irrespective of the therapeutic intervention. A consensus on endpoints is urgently required to set a global standard for the reporting of study results and to enable inter-study comparisons. Future prospective database studies are needed to validate these endpoints.

LAY SUMMARY

Consensus among international experts on response criteria and endpoints in autoimmune hepatitis is lacking. A consensus on endpoints is urgently required to set a global standard for the reporting of study results and to enable the comparison of results between clinical trials. Therefore, the International Autoimmune Hepatitis Group (IAIHG) herein presents a statement on 5 agreed response criteria and endpoints: complete biochemical response, insufficient response, non-response, remission, and intolerance to treatment, which can be used to guide future reporting.

Do people change their eating habits after a diagnosis of cancer? A systematic review

INTRODUCTION

People who live with and beyond cancer are thought to be motivated to change their diet. However, there is a lack of reviews conducted on what specific dietary changes people make and further evaluation may inform future interventional studies. Hence, we aim to summarise the evidence on dietary changes in observational studies before and after a cancer diagnosis.

METHODS

This systematic review followed the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis. Electronic searches were conducted in four databases to identify cohort and cross-sectional studies on dietary changes before and after a cancer diagnosis, excluding studies that evaluated an intervention. Quality assessment was undertaken, and meta-analyses were conducted where suitable.

RESULTS

We identified 14 studies with 16,443 participants diagnosed with cancer, age range 18-75 years. Dietary change was assessed <1-5 years before diagnosis and up to 12-years post-diagnosis. Meta-analyses showed that the standard mean difference (SMD) for energy (SMD-0.32, 95% CI -0.46 to -0.17) and carbohydrate consumption (SMD 0.20, 95% CI -0.27 to -0.14). Studies showed inconsistent findings for fat, protein, and fibre, most food groups, and supplement intake. A small decrease in red and processed meat consumption was consistently reported.

CONCLUSION

All studies reported some positive changes in dietary intake and supplement consumption after receiving a cancer diagnosis without any intervention. However, differences for food groups and nutrients were mainly small and not necessarily clinically meaningful. Evidence demonstrates that a cancer diagnosis alone is insufficient to motivate people to change their dietary intake, indicating that most people would benefit from a dietary intervention to facilitate change. This article is protected by copyright. All rights reserved.

A209 EXPERT CONSENSUS CRITERIA AND PRACTICAL RECOMMENDATIONS FOR PBC CARE IN THE COVID-19 ERA AND BEYOND

Background

Primary biliary cholangitis (PBC) is a chronic autoimmune cholestatic liver disease that can progress to liver fibrosis and cirrhosis, and requires timely diagnosis, optimal treatment, and risk stratification. Several guidelines for the management of PBC have been published, including the American Association for the Study of Liver Disease (AASLD) and European Association for the Study of the Liver (EASL) Clinical Practice Guidelines, which include goals for standards of PBC care. However, recent audits have identified deficiencies in real-world PBC care. In addition, the global coronavirus (COVID-19) pandemic has generally reduced access to care, diminished healthcare resources and accelerated the use of remote patient management. There is therefore a need for simple, actionable guidance that physicians can implement in order to maintain standards of care in PBC in the new environment.

Aims

A working group of ten PBC specialists from Europe and Canada were convened by Intercept Pharmaceuticals in January 2020 with the aim of defining key criteria for the care of patients with PBC.

Methods

Following the outbreak of the COVID-19 pandemic, based on these criteria, a smaller working group of six PBC specialists developed practical recommendations to assist physicians in maintaining standards of care and to guide remote management of patients.

Results

The working group defined five key criteria for care in PBC, encompassing PBC diagnosis, initiation of first line therapy with ursodeoxycholic acid (UDCA), risk stratification on UDCA, symptom management, and initiation of 2L therapy. The group developed 21 practical recommendations for the management of patients with PBC in the COVID-19 environment including modality, frequency and timing of investigations and monitoring. (Figure 1).

Conclusions

The delivery of PBC care during the COVID-19 pandemic carries significant challenges. These consensus criteria and practical recommendations provide guidance for the management of PBC during the pandemic era and beyond.

Funding Agencies

NoneIntercept Pharmaceutical

Modulation of Acetylcholinesterase Activity Using Molecularly Imprinted Polymer Nanoparticles

Modulation of enzyme activity allows for control over many biological pathways and while strategies for the pharmaceutical design of inhibitors are well established; methods for promoting activation, that is an...

Alcohol packaging as a promotional tool: A focus group study with young adult drinkers in Scotland

Background

Given the dearth of research on consumer perceptions of alcohol packaging as a marketing tool, with existing studies focused on children and adolescents, our aim was to explore how young adults view and engage with alcohol packaging.

Methods

Eight focus groups were conducted in Glasgow (Scotland) in September 2019 with young adult drinkers (n = 50), segmented by age (18-24, 25-35), gender (female, male) and social grade (ABC1, C2DE). Participants were shown, allowed to handle, and asked about, a range of alcoholic products. Data were analysed thematically using an inductive approach.

Results

Five main themes emerged from the data. The first was the ubiquity of alcohol packaging, with frequent exposure reported in different settings, such as shops and drinking venues, and via marketing. The second was appeal, with pack graphics (e.g. colour), structure (e.g. shape, size) and promotions (e.g. gifts, limited-editions) allowing alcohol packs to capture attention, enable products to stand out on shelves, and help create product and brand liking, interest and choice. Third, alcohol packaging was frequently associated with specific occasions and activities. Fourth, alcohol packaging informed perceptions of product-consumer targeting, suitability, and intended drinker profiles. Fifth, alcohol packaging also engaged non-visual senses, guiding expectations of product taste and palatability.

Conclusions

For young adult drinkers in Scotland, alcohol packaging can capture attention, create appeal, and help shape perceptions of the product, drinker and drinking experience.

Key messages

Alcohol packaging is a key marketing communications vehicle, which can attract attention, create product and brand liking, interest and choice, guide expectations, and influence purchasing decisions. Alcohol packaging conveys messages of consumer-product suitability and acceptability, helping to reinforce perceptions that alcohol is a desirable product via pack structure, graphics, and promotions.

P07.04 Rapid-CNS2: Rapid comprehensive adaptive nanopore-sequencing of CNS tumors, a proof of concept study

BACKGROUND

The WHO classification 2021 includes multiple molecular markers for routine diagnostics in addition to histology. Sequencing setup for complete molecular profiling requires considerable investment, while batching samples for sequencing and methylation profiling can delay turnaround time. We introduce RAPID-CNS2, a nanopore adaptive sequencing pipeline that enables comprehensive mutational, methylation and copy number profiling of CNS tumours with a single third generation sequencing assay. It can be run for single samples and offers highly flexible target selection requiring no additional library preparation.

MATERIAL AND METHODS

Utilising ReadFish, a toolkit enabling targeted nanopore sequencing, we sequenced DNA from 22 diffuse glioma patient samples on a MinION device. Target regions comprised our Heidelberg brain tumour NGS panel and pre-selected CpG sites for methylation classification by an adapted random forest classifier. Pathognomonic alterations, copy number profiles, and methylation classes were called using a custom bioinformatics pipeline. Results were compared to their corresponding NGS panel-seq and EPIC array outputs.

RESULTS

Complete concordance with the EPIC array was found for copy number profiles from RAPID-CNS2. 94% pathognomonic mutations were congruent with NGS panel-seq. MGMT promoter status was correctly identified in all samples. Methylation families were detected with 96% congruence. Among the alterations decisive for rendering a classification-compatible integrated diagnosis, 97% of the alterations were consistent over the entire cohort (completely congruent in 19/22 cases and sufficient for unequivocal diagnosis in all).

CONCLUSION

RAPID-CNS2 provides a swift and highly flexible alternative to conventional NGS and array-based methods for SNV/Indel analysis, detection of copy number alterations and methylation classification. The turnaround time of ~4 days can be further shortened to &lt;12h by altering target sizes. It offers a low-capital approach that would be cost-efficient for low throughput settings and invaluable in cases requiring immediate diagnoses.

The LeVe CPAP System for Oxygen-Efficient CPAP Respiratory Support: Development and Pilot Evaluation

Background: The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has placed a significant demand on healthcare providers (HCPs) to provide respiratory support for patients with moderate to severe symptoms. Continuous Positive Airway Pressure (CPAP) non-invasive ventilation can help patients with moderate symptoms to avoid the need for invasive ventilation in intensive care. However, existing CPAP systems can be complex (and thus expensive) or require high levels of oxygen, limiting their use in resource-stretched environments. Technical Development + Testing: The LeVe ("Light") CPAP system was developed using principles of frugal innovation to produce a solution of low complexity and high resource efficiency. The LeVe system exploits the air flow dynamics of electric fan blowers which are inherently suited to delivery of positive pressure at appropriate flow rates for CPAP. Laboratory evaluation demonstrated that performance of the LeVe system was equivalent to other commercially available systems used to deliver CPAP, achieving a 10 cm H2O target pressure within 2.4% RMS error and 50-70% FiO2 dependent with 10 L/min oxygen from a commercial concentrator. Pilot Evaluation: The LeVe CPAP system was tested to evaluate safety and acceptability in a group of ten healthy volunteers at Mengo Hospital in Kampala, Uganda. The study demonstrated that the system can be used safely without inducing hypoxia or hypercapnia and that its use was well-tolerated by users, with no adverse events reported. Conclusions: To provide respiratory support for the high patient numbers associated with the COVID-19 pandemic, healthcare providers require resource efficient solutions. We have shown that this can be achieved through frugal engineering of a CPAP ventilation system, in a system which is safe for use and well-tolerated in healthy volunteers. This approach may also benefit other respiratory conditions which often go unaddressed in Low and Middle Income Countries (LMICs) for want of context-appropriate technology designed for the limited oxygen resources available.

A cost analysis of cardiac magnetic resonance imaging in the diagnostic pathway of a population with unexplained acute myocardial injury and normal coronary angiography

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): National Institute for Health Research (NIHR) Biomedical Research Centre at St Bartholomew"s Hospital London. Irish Cardiac Society

OnBehalf

European Association of Cardiovascular Imaging (EACVI) -Task Force for Cost Effectiveness.

Background

Acute presentations with myocardial injury that occur despite culprit-free coronary angiography were first reported over 70 years ago, with a prevalence between 5-9%.  1-3 There is increasing evidence that a more accurate diagnosis is available and that CMR is a key tool to determine the underlying pathology. This is reflected with the most recent international guidelines advocating for the use of CMR in the diagnostic pathways of this heterogeneous population.  However, to date there is no formal assessment of the financial implications of adopting these new guidelines.

Purpose

To determine the financial impact of implementing cardiac magnetic resonance imaging in the diagnostic pathway of a population with unexplained acute myocardial injury and normal coronary angiography in comparison to existing clinical practice.

Methods

We performed a focused cost-benefit analysis using a hypothetical population of 2,000 patients with unexplained acute myocardial injury and normal coronary angiography.  The population was split evenly into two groups of either standard, or CMR guided management, and extrapolated over a ten-year period. Standard management was defined as 66% of the population receiving dual antiplatelet therapy (ticagrelor and aspirin) for one year followed by aspirin for life, and the remaining 34% of the population receiving aspirin for life. CMR guided management determined antiplatelet therapy according to the imaging findings. This analysis focused on CMR’s ability to accurately identify those patients who may have had an MI and facilitate tailored treatment with evidence based dual antiplatelet therapy. Costs and rates were defined in Table 1. A one-way sensitivity analysis was also performed to determine the variables with largest impact on the costs. Each variable was varied by +/- 20% and the change in cost determined at year 10.

Results

Using CMR in the diagnostic pathway resulted in an increased cost of £72,656 in the first year. After year 7, CMR guided practice becomes cost neutral, resulting in cost saving of £24,054 over a ten-year period in a population of 1000 patients. Figure 1. Utilizing CMR in this population also resulted in 7 fewer myocardial infarctions and 14 fewer major bleeding events over a ten-year time horizon.

The three most sensitive variables were, in decreasing order, the cost of CMR, the cost of ticagrelor and the percentage of the population with MI requiring DAPT. A 20% change from baseline resulted in a 320%, 247% and 162% change in costs at 10 years, respectively.

Conclusion

Utilizing CMR in this population may be associated with reduced costs in the medium to long term. The initial increased cost of CMR is offset over time, by delivering a more personalised, higher quality level of care to patients.

Spatial behaviour of sheep during the neonatal period: Preliminary study on the influence of shelter

Effective shelter has been demonstrated to reduce neonatal lamb mortality rates during periods of inclement weather. Periods of high wind speed and rainfall have been shown to influence shelter usage; however, it is not yet known how ewe factors such as breed, age and body condition score influence shelter-seeking behaviour. This study, conducted on a working upland farm in the UK, examined impact of artificial shelter on the biological and climatic factors that influence peri-parturient ewe behaviour. Pregnant ewes (n = 147) were randomly allocated between two adjacent fields which were selected for their similarity in size, topography, pasture management, orientation to the prevailing wind and available natural shelter. In one field, three additional artificial shelters were installed to increase the available shelter for ewes, this field was designated the Test field; no additional artificial shelter was provided in the second field which was used as the Control field. Individual ewes were observed every 2 h between 0800 and 1600 for 14 continuous days to monitor their location relative to shelter. Ewe breed (Aberfield and Highlander), age (2-8 years) and body condition score were considered as explanatory variables to explain flock and individual variance in shelter-seeking behaviour and the prevalence of issues which required the intervention of the shepherd, termed 'shepherding problems'. Any ewe observed with dystocia, a dead or poor vigour lamb or who exhibited mismothering behaviour was recorded as a shepherding problem. The prevalence of these shepherding problems which necessitate human intervention represents arguably the most critical limiting factor for the successful management of commercial sheep flocks in outdoor lambing systems. Overall, ewes in the Test field with access to additional artificial shelter experienced fewer shepherding problems than those in the Control field (P < 0.05). A significant breed effect was also observed, with Highlander ewes more likely to seek shelter than Aberfield ewes (P < 0.001), and experiencing significantly fewer shepherding interventions (P < 0.05). These findings demonstrate the substantial and significant benefits to animal welfare and productivity that can be achieved through the provision of shelter in commercial, upland, outdoor lambing systems in the UK.

POS0311 NEUROIMAGING BIOMARKERS IN INDIVIDUALS WITH AND WITHOUT RHEUMATOID ARTHRITIS: RESULTS FROM THE MAYO CLINIC STUDY OF AGING

Background:

Age-related increase in the burden of systemic inflammation is an established key player and potential treatment target in Alzheimer’s disease (AD) and other age-related dementias. (Dregan, Chowienczyk et al. 2015) Although rheumatoid arthritis (RA) is an autoimmune hyper-inflammatory disease, studies on RA and dementia or vascular neuroimaging biomarkers are lacking.

Objectives:

To examine the associations between RA and dementia/vascular neuroimaging biomarkers in the Mayo Clinic Study of Aging (MCSA).

Methods:

The study consisted of 35 RA cases in MCSA and 104 MCSA participants without RA matched 1:3 for age, sex, education, cognitive status (≥50 years old) at baseline and the availability of at least one magnetic resonance imaging (MRI). The primary outcome measures were well established dementia-related neuroimaging biomarkers, including global beta-amyloid (Aβ) using PiB-positron-emission tomography (PET; n=47); neurodegeneration (hypometabolism via FDG-PET (n=45), hippocampal volume (n=139), and cortical thickness via structural MRI [n=138], and cerebrovascular pathology via FLAIR-MRI (white matter hyperintensity [WMH; n=49] burden, subcortical, and cortical infarctions (n=55)). Elevated 11C-PiB-PET was defined as standardized uptake value ratio ≥1.48 in an Alzheimer’s disease (AD)-related region of interest and reduced AD signature cortical thickness as ≤2.68mm (neurodegeneration; N+). Kruskal-Wallis rank sum and Pearson’s chi-squared tests were used to compare the neuroimaging measures between participants with and without RA.

Results:

Participants with vs. without-RA did not differ in age, sex, years of education, major comorbidities, Aβ burden, hippocampal volume, and neurodegeneration measures (Table 1). Although the sample size was small, we observed that RA participants (vs. without-RA) had greater mean WMH volume (relative to the total intracranial volume (TIV) (mean (SD) %: 1.12 (0.57) % vs 0.76 (0.69) % of TIV, p=0.011), were more likely to have cortical infarctions (4 vs.1; p=0.013) and had a higher mean number of cortical infarctions (mean (SD): 0.24 (0.44) vs. 0.05 (0.32), p=0.017).

Table 1.

Participants’ baseline characteristics.

With RAWithout RATotalp value*Age, mean (SD)76.3 (7.9)75.9 (7.9)1390.82Male13 (37%)37 (36%)1390.87Education (years), mean (SD)14.5 (2.5)14.3 (2.4)1390.75Apolipoprotein E ε4 carrier6 (17%)28 (27%)1390.24Cognitively unimpaired27 (77%)83 (80%)1100.94Mild cognitive impairment7 (20%)18 (17%)25Dementia1 (3%)3 (3%)4Reduced AD signature cortical thickness20 (57%)60 (58%)1380.91Elevated β-amyloid4 (33%)11 (31%)470.90FDG PET SUVR1.52 (0.16)1.59 (0.18)450.46White matter hyperintensity volume % of TIV1.12 (0.57)0.76 (0.69)490.011With cortical infarctions4 (24%)1 (3%)550.013

N (%) unless otherwise stated; * Kruskal-Wallis rank sum or Pearson’s Chi-squared test.

SD=standard deviation; AD= Alzheimer’s disease; SUVR=standardized uptake value ratio; TIV= Total intracranial volume.

Conclusion:

Our preliminary data suggest significant differences in cerebrovascular biomarker measures by RA status. Further studies would add valuable information to our understanding and insight into the development of interventions for the prevention of cerebrovascular pathology in RA patients.

References:

[1]Dregan, A., P. Chowienczyk and M. C. Gulliford (2015). “Are Inflammation and Related Therapy Associated with All-Cause Dementia in a Primary Care Population?” J Alzheimers Dis 46(4): 1039-1047.

Acknowledgements:

The study was supported by the NIH AG068192. The Mayo Clinic Study of Aging was supported by the NIH (U01 AG006786, P50 AG016574, R01AG057708, R01 AG011378, R01 AG021927, R01 AG041851, R01 NS097495), the Alexander Family Alzheimer’s Disease Research Professorship of the Mayo Clinic, Mayo Foundation for Medical Education and Research, the Liston Award, the Schuler Foundation and was made possible by the Rochester Epidemiology Project (R01 AG034676).

Disclosure of Interests:

Maria Vassilaki Shareholder of: M. Vassilaki has equity ownership in Abbott Laboratories, Johnson and Johnson, Medronic and Amgen., Grant/research support from: M. Vassilaki has received research funding from Roche and Biogen in the past., Cynthia S. Crowson: None declared, John M Davis III Grant/research support from: JM. Davis III receives research funding from Pfizer., Stephanie Duong: None declared, David Jones: None declared, Michelle Mielke Consultant of: M. Mielke has consulted for Biogen and Brain Protection Company, Prashanthi Vemuri: None declared, Elena Myasoedova: None declared

Cardiorespiratory fitness and electroanatomical remodelling in patients with atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Introduction

Atrial fibrillation (AF) is the most common clinically-relevant arrhythmia. Its initiation and maintenance is linked to the presence cardiovascular risk factors such as hypertension and obesity. Higher cardiorespiratory fitness (CRF) has been associated with a better prognosis. However, specific electroanatomical features associated with baseline CRF have not been described. 

Purpose

Compare electroanatomical substrate across exercise capacity levels in patients with AF

Methods

Patients referred for de novo AF radiofrequency ablation at the Centre for Heart Rhythm Disorders from August 2017 until June 2020 were screened for inclusion and CRF was evaluated in metabolic equivalents (METs) by a symptom-limited maximal treadmill exercise test using the standard Bruce protocol prior to ablation. Predicted CRF was calculated based on established equations and patients were categorized according to the percentage of predicted CRF achieved; low (&lt;85%), adequate (85-100%) and high (&gt;100%). Total mean and regional peak-to-peak bipolar voltages, percent of low voltage areas (% LVA), conduction velocity (CV) and percent of complex fractionated electrograms (% CFE) in sinus rhythm were compared across groups. 

Results

There were no between-group differences in baseline characteristics, medication use or echocardiographic features. Total mean voltage was significantly lower in the low CRF group compared to both adequate and high CRF. Compared to the high CRF group, roof (3.25 ± 1.2 mV vs 1.9 ± 1.3 mV, p &lt; 0.05), posterior (3.8 ± 1.8 mV vs 1.7 ± 0.9 mV, p &lt; 0.001) and inferior mean voltages (3.4 ± 2 mV vs 1.6 ± 0.7 mV, p &lt; 0.05) were significantly lower in the low CRF group (figure 1A). Furthermore, compared with the adequate CRF group, mean voltages were significantly lower in the posterior (3.7 ± 1.5 mV vs 1.7 ± 0.9 mV, p &lt; 0.001), inferior (3.4 ± 1 mV vs 1.6 ± 0.7 mV, p &lt; 0.001) and lateral (4.2 ± 2.2 mV vs 2.1 ± 1.4 mV, p &lt; 0.05) walls of the low CRF group. Anterior and septal mean voltages were not significantly different across CRF groups (P for trend = 0.07, 0.3 and 0.15, respectively). Conduction velocities were not significantly different across groups. The inferior %LVA was significantly higher in the low CRF (5.6 ± 6%) compared to adequate CRF group (23 ± 18%) (p &lt; 0.05) (figure 1B). Total and regional % CFE was higher in the low CRF compared to adequate and high CRF.

Conclusion

Participants in the lower baseline CRF category showed significant reductions in regional voltages along with higher fractionation with preserved conduction velocities. Research on the effect of physical activity and CRF on left atrial arrhythmogenic substrate is required.

Abstract Figure. Global and regional mV and % LVA by CRF