Identification of a Multiplex Biomarker Panel for Hypertrophic Cardiomyopathy Using Quantitative Proteomics and Machine Learning.

Hypertrophic cardiomyopathy (HCM) is defined by pathological left ventricular hypertrophy (LVH). It is the commonest inherited cardiac condition and a significant number of high risk cases still go undetected until a sudden cardiac death (SCD) event. Plasma biomarkers do not currently feature in the assessment of HCM disease progression, which is tracked by serial imaging, or in SCD risk stratification, which is based on imaging parameters and patient/family history. There is a need for new HCM plasma biomarkers to refine disease monitoring and improve patient risk stratification. To identify new plasma biomarkers for patients with HCM, we performed exploratory myocardial and plasma proteomics screens and subsequently developed a multiplexed targeted liquid chromatography-tandem/mass spectrometry-based assay to validate the 26 peptide biomarkers that were identified. The association of discovered biomarkers with clinical phenotypes was prospectively tested in plasma from 110 HCM patients with LVH (LVH+ HCM), 97 controls, and 16 HCM sarcomere gene mutation carriers before the development of LVH (subclinical HCM). Six peptides (aldolase fructose-bisphosphate A, complement C3, glutathione S-transferase omega 1, Ras suppressor protein 1, talin 1, and thrombospondin 1) were increased significantly in the plasma of LVH+ HCM compared with controls and correlated with imaging markers of phenotype severity: LV wall thickness, mass, and percentage myocardial scar on cardiovascular magnetic resonance imaging. Using supervised machine learning (ML), this six-biomarker panel differentiated between LVH+ HCM and controls, with an area under the curve of ≥ 0.87. Five of these peptides were also significantly increased in subclinical HCM compared with controls. In LVH+ HCM, the six-marker panel correlated with the presence of nonsustained ventricular tachycardia and the estimated five-year risk of sudden cardiac death. Using quantitative proteomic approaches, we have discovered six potentially useful circulating plasma biomarkers related to myocardial substrate changes in HCM, which correlate with the estimated sudden cardiac death risk.

Maintenance of Serum Potassium Levels ≥3.6 mEq/L Versus ≥4.5 mEq/L After Isolated Elective Coronary Artery Bypass Grafting and the Incidence of New-Onset Atrial Fibrillation: Pilot and Feasibility Study Results.

OBJECTIVE: Serum potassium levels frequently are maintained at high levels (≥4.5 mEq/L) to prevent atrial fibrillation after cardiac surgery (AFACS), with limited evidence. Before undertaking a noninferiority randomized controlled trial to investigate the noninferiority of maintaining levels ≥3.6 mEq/L compared with this strategy, the authors wanted to assess the feasibility, acceptability, and safety of recruiting for such a trial. DESIGN: Pilot and feasibility study of full trial protocol. SETTING: Two university tertiary-care hospitals. PARTICIPANTS: A total of 160 individuals undergoing first-time elective isolated coronary artery bypass grafting. INTERVENTIONS: Randomization (1:1) to protocols aiming to maintain serum potassium at either ≥3.6 mEq/L or ≥4.5 mEq/L after arrival in the postoperative care facility and for 120 hours or until discharge from the hospital or AFACS occurred, whichever happened first. MEASUREMENTS AND MAIN RESULTS: Primary outcomes: (1) whether it was possible to recruit and randomize 160 patients for six months (estimated 20% of those eligible); (2) maintaining supplementation protocol violation rate ≤10% (defined as potassium supplementation being inappropriately administered or withheld according to treatment allocation after a serum potassium measurement); and (3) retaining 28-day follow-up rates ≥90% after surgery. Between August 2017 and April 2018, 723 patients were screened and 160 (22%) were recruited. Potassium protocol violation rate = 9.8%. Follow-up rate at 28 days = 94.3%. Data on planned outcomes for the full trial also were collected. CONCLUSIONS: It is feasible to recruit and randomize patients to a study assessing the impact of maintaining serum potassium concentrations at either ≥3.6 mEq/L or ≥4.5 mEq/L on the incidence of AFACS.

Doing Simple Things Well: Practice Advisory Implementation Reduces Atrial Fibrillation After Cardiac Surgery.

OBJECTIVES: The authors aimed to adapt a practice advisory for the prevention of atrial fibrillation after cardiac surgery (AFACS) recently published in this journal into the authors' local perioperative protocols, implementing the recommendations, with a focus on early postoperative (re)introduction of ß-blockers and overcoming frequent guideline implementation barriers. DESIGN: Development of a prevention care bundle and repeated audit after a model of improvement approach with retrospective analysis. SETTING: Single center (tertiary academic hospital). PARTICIPANTS: A total of 384 patients in 2 cohorts of consecutive patients undergoing open cardiac surgery before and after hospital-wide implementation of a care bundle. INTERVENTIONS: After auditing the standard of care in the authors' center, an AFACS prevention care bundle was designed and implemented, consisting of a graphic tool with 5 pillars based on current evidence for the early postoperative phase. Multidisciplinary teaching and training of staff were delivered, and a second audit was conducted after the implementation period. MEASUREMENTS AND MAIN RESULTS: Significantly more patients received postoperative ß-blockers after care bundle implementation (82.7% pre- v 91.3% post-bundle, p = 0.019), with a higher proportion on day 1 (36.7% pre- v 67% post-bundle, p < 0.001), indicating a successful uptake. The incidence of AFACS was significantly reduced from 35.4% to 23.3% (p = 0.009), with a particularly marked reduction in the age group 65- to 75- years and for isolated aortic valve and coronary artery bypass graft surgery. CONCLUSION: An AFACS prevention care bundle improved adherence to current guidelines with regard to early ß-blocker administration and significantly reduced the incidence of atrial fibrillation after cardiac surgery.

Society of Cardiovascular Anesthesiologists/European Association of Cardiothoracic Anaesthetists Practice Advisory for the Management of Perioperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery.

Postoperative atrial fibrillation (poAF) is the most common adverse event after cardiac surgery and is associated with increased morbidity, mortality, and hospital and intensive care unit length of stay. Despite progressive improvements in overall cardiac surgical operative mortality and postoperative morbidity, the incidence of poAF has remained unchanged at 30%-50%. A number of evidence-based recommendations regarding the perioperative management of atrial fibrillation (AF) have been released from leading cardiovascular societies in recent years; however, it is unknown how closely these guidelines are being followed by medical practitioners. In addition, many of these society recommendations are based on patient stratification into "normal" and "elevated" risk groups for AF, but criteria for that stratification have not been clearly defined. In an effort to improve the perioperative management of AF, the Society of Cardiovascular Anesthesiologists (SCA) Clinical Practice Improvement Committee developed a multidisciplinary Atrial Fibrillation Working Group that created a summary of current best practice based on a distillation of recent guidelines from professional societies involved in the care of cardiac surgical patients. An evidence-based set of survey questions was then generated to describe the current practice of perioperative AF management. Through collaboration with the European Association of Cardiothoracic Anaesthetists (EACTA), that survey was distributed to the combined memberships of both the SCA and EACTA, yielding 641 responses and resulting in the most comprehensive understanding to date of perioperative AF management in North America, Europe, and beyond. The survey data demonstrated the broad range of therapies utilized for the prevention and treatment of poAF, as well as a spectrum of adherence to published guidelines. With the goal of improving adherence, a graphical advisory tool was created with an easily accessible format that could be utilized for bedside management. Finally, given that no evidence-based threshold currently exists to differentiate patients at normal risk to develop poAF from those at elevated risk, the SCA/EACTA AF working group created a list of poAF risk factors using expert opinion and based on published risk score models for poAF. This approach allows stratification of patients into risk groups and facilitates adherence to the evidence-based recommendations summarized in the graphical advisory tool. It is our hope that these new additions to the clinical toolkit for the management of perioperative AF will improve the evidence-based care and outcomes of cardiac surgical patients worldwide.

Opioid-Based Anesthesia and Analgesia for Adult Cardiac Surgery: History and Narrative Review of the Literature.

Opioids have played in a key role in cardiac anesthesia and analgesia since the early years of cardiac surgery. Today, opioids continue to be the primary mode for analgesia in cardiac surgery, yet there is considerable variability in the choice, dose and route of used. A history of the use of opioids in cardiothoracic anesthesia is presented, followed by an examination of the differences among current opioids in use and of outcome variables important in cardiac anesthesia, such as postoperative analgesia, extubation times, fast-track cardiac anesthesia, chronic neuropathic pain, and cardioprotection. Topical issues such as the role of perioperative opioid use in the global opioid crisis, opioid-sparing techniques and novel opioids in development are also discussed.

Society of Cardiovascular Anesthesiologists/European Association of Cardiothoracic Anaesthetists Practice Advisory for the Management of Perioperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery.

Postoperative atrial fibrillation (poAF) is the most common adverse event after cardiac surgery and is associated with increased morbidity, mortality, and increased hospital and intensive care unit length of stay. Despite progressive improvements in overall cardiac surgical operative mortality and postoperative morbidity, the incidence of poAF has remained unchanged at 30% to 50%. A number of evidence-based recommendations regarding the perioperative management of atrial fibrillation (AF) have been released from leading cardiovascular societies in recent years; however, it is unknown how closely these guidelines are being followed by medical practitioners. In addition, many of these society recommendations are based on patient stratification into "normal" and "elevated" risk groups for AF, but criteria for that stratification have not been defined clearly. In an effort to improve the perioperative management of AF, the Society of Cardiovascular Anesthesiologists (SCA) Clinical Practice Improvement Committee developed a multidisciplinary Atrial Fibrillation Working Group that created a summary of current best practices based on distillation of recent guidelines from professional societies involved in the care of cardiac surgical patients. An evidence-based set of survey questions then was generated to describe the current practice of perioperative AF management. Through a collaboration with the European Association of Cardiothoracic Anaesthetists (EACTA), that survey was distributed to the combined memberships of both the SCA and the EACTA, yielding 641 responses and resulting in the most comprehensive understanding to date of perioperative AF management in North America and Europe and beyond. The survey data demonstrated the broad range of therapies used for prevention and treatment of poAF, as well as a spectrum of adherence to published guidelines. With the goal of improving adherence, a graphical advisory tool was created with an easily accessible format that could be used for bedside management. Finally, given that no evidence-based threshold currently exists to differentiate patients at normal risk of developing poAF from those at elevated risk, the SCA/EACTA AF working group created a list of poAF risk factors using expert opinion, based on published risk score models for poAF. This allows stratification of patients into risk groups and facilitates adherence to the evidence-based recommendations summarized in the graphical advisory tool. It is the working group's hope that these new additions to the clinical toolkit for management of perioperative AF will improve the evidence-based care and outcomes of cardiac surgical patients worldwide.

Can Transesophageal Echocardiography Be Performed Safely Using a Laryngeal Mask Airway During Atrial Fibrillation Ablation?

OBJECTIVE: To investigate the feasibility and safety of using a laryngeal mask airway (LMA) compared with a cuffed oral endotracheal tube (COETT) for atrial fibrillation (AF) ablation with transesophageal echocardiography (TEE). DESIGN: Prospective, cohort study. SETTING: A single-center inner-city hospital. PARTICIPANTS: The study comprised adult patients undergoing elective AF ablation with periprocedural TEE over a 3-year period. INTERVENTIONS: Patients were treated with either an LMA or a COETT before undergoing a standardized protocol for TEE and AF ablation. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the need for conversion from an LMA to a COETT. Between January 2014 and January 2017, 346 patients underwent AF ablation. Of those, 126 procedures were performed with a COETT (36.4%) and 220 (63.6%) with an LMA. There were no differences between groups in terms of baseline characteristics, including age, sex, body mass index, and American Society of Anesthesiologists grade. An adequate airway seal was unable to be maintained in 3 patients in the LMA group (1.4%), and those patients were converted to a COETT. No episodes of airway complications occurred in either group. No difference was found in mean propofol (2%) dose between COETT and LMA (385 mg/h v 374 mg/h; p = 0.127). However, the mean remifentanil dose (100 µg/mL) was reduced significantly in the LMA group compared with the COETT group at 355 µg/h and 939 µg/h, respectively (p < 0.001). CONCLUSIONS: LMA use is safe and feasible in the vast majority of patients undergoing AF ablation with TEE and is an acceptable alternative to COETT. A significantly reduced rate of remifentanil was required to maintain anesthesia in the LMA group.

Systolic anterior motion of the anterior mitral valve leaflet begins in subclinical hypertrophic cardiomyopathy.

AIMS: Anterior mitral valve leaflet (AMVL) elongation is detectable in overt and subclinical hypertrophic cardiomyopathy (HCM). We sought to investigate the dynamic motion of the aorto-mitral apparatus to understand the behaviour of the AMVL and the mechanisms of left ventricular outflow tract obstruction (LVOTO) predisposition in HCM. METHODS AND RESULTS: Cardiovascular magnetic resonance imaging using a 1.5 Tesla scanner was performed on 36 HCM sarcomere gene mutation carriers without left ventricular hypertrophy (G+LVH-), 31 HCM patients with preserved ejection fraction carrying a pathogenic sarcomere gene mutation (G+LVH+), and 53 age-, sex-, and body surface area-matched healthy volunteers. Dynamic excursion of the aorto-mitral apparatus was assessed semi-automatically on breath-held three-chamber cine steady-state free precession images. Four pre-defined regions of interest (ROIs) were tracked: ROIPMVL: hinge point of the posterior mitral valve leaflet; ROITRIG: intertrigonal mitral annulus; ROIAMVL: AMVL tip; and ROIAAO: anterior aortic annulus. Compared with controls, normalized two-dimensional displacement-vs.-time plots in G+LVH- revealed subtle but significant systolic anterior motion (SAM) of the AMVL (P < 0.0001) and reduced longitudinal excursion of ROIAAO (P = 0.014) and ROIPMVL (P = 0.048). In overt and subclinical HCM, excursion of the ROITRIG/AMVL/PMVL was positively associated with the burden of left ventricular fibrosis (P < 0.028). As expected, SAM was observed in G+LVH+ together with reduced longitudinal excursion of ROITRIG (P = 0.049) and ROIAAO (P = 0.008). CONCLUSION: Dyskinesia of the aorto-mitral apparatus, including SAM of the elongated AMVL, is detectable in subclinical HCM before the development of LVH or left atrial enlargement. These data have the potential to improve our understanding of early phenotype development and LVOTO predisposition in HCM.

Current practices in nutrition therapy in cardiac surgery patients: An international multicenter observational study.

BACKGROUND: Cardiac surgery patients with a prolonged stay in the intensive care unit (ICU) are at high risk for acquired malnutrition. Medical nutrition therapy practices for cardiac surgery patients are unknown. The objective of this study is to describe the current nutrition practices in critically ill cardiac surgery patients worldwide. METHODS: We conducted a prospective observational study in 13 international ICUs involving mechanically ventilated cardiac surgery patients with an ICU stay of at least 72 h. Collected data included the energy and protein prescription, type of and time to the initiation of nutrition, and actual quantity of energy and protein delivered (maximum: 12 days). RESULTS: Among 237 enrolled patients, enteral nutrition (EN) was started, on average, 45 h after ICU admission (range, 0-277 h; site average, 53 [range, 10-79 h]). EN was prescribed for 187 (79%) patients and combined EN and parenteral nutrition in 33 (14%). Overall, patients received 44.2% (0.0%-117.2%) of the prescribed energy and 39.7% (0.0%-122.8%) of the prescribed protein. At a site level, the average nutrition adequacy was 47.5% (30.5%-78.6%) for energy and 43.6% (21.7%-76.6%) for protein received from all nutrition sources. CONCLUSION: Critically ill cardiac surgery patients with prolonged ICU stay experience significant delays in starting EN and receive low levels of energy and protein. There exists tremendous variability in site performance, whereas achieving optimal nutrition performance is doable.

Plasma proteomic signature predicts who will get persistent symptoms following SARS-CoV-2 infection.

BACKGROUND: The majority of those infected by ancestral Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) during the UK first wave (starting March 2020) did not require hospitalisation. Most had a short-lived mild or asymptomatic infection, while others had symptoms that persisted for weeks or months. We hypothesized that the plasma proteome at the time of first infection would reflect differences in the inflammatory response that linked to symptom severity and duration. METHODS: We performed a nested longitudinal case-control study and targeted analysis of the plasma proteome of 156 healthcare workers (HCW) with and without lab confirmed SARS-CoV-2 infection. Targeted proteomic multiple-reaction monitoring analysis of 91 pre-selected proteins was undertaken in uninfected healthcare workers at baseline, and in infected healthcare workers serially, from 1 week prior to 6 weeks after their first confirmed SARS-CoV-2 infection. Symptom severity and antibody responses were also tracked. Questionnaires at 6 and 12 months collected data on persistent symptoms. FINDINGS: Within this cohort (median age 39 years, interquartile range 30-47 years), 54 healthcare workers (44% male) had PCR or antibody confirmed infection, with the remaining 102 (38% male) serving as uninfected controls. Following the first confirmed SARS-CoV-2 infection, perturbation of the plasma proteome persisted for up to 6 weeks, tracking symptom severity and antibody responses. Differentially abundant proteins were mostly coordinated around lipid, atherosclerosis and cholesterol metabolism pathways, complement and coagulation cascades, autophagy, and lysosomal function. The proteomic profile at the time of seroconversion associated with persistent symptoms out to 12 months. Data are available via ProteomeXchange with identifier PXD036590. INTERPRETATION: Our findings show that non-severe SARS-CoV-2 infection perturbs the plasma proteome for at least 6 weeks. The plasma proteomic signature at the time of seroconversion has the potential to identify which individuals are more likely to suffer from persistent symptoms related to SARS-CoV-2 infection. FUNDING INFORMATION: The COVIDsortium is supported by funding donated by individuals, charitable Trusts, and corporations including Goldman Sachs, Citadel and Citadel Securities, The Guy Foundation, GW Pharmaceuticals, Kusuma Trust, and Jagclif Charitable Trust, and enabled by Barts Charity with support from University College London Hospitals (UCLH) Charity. This work was additionally supported by the Translational Mass Spectrometry Research Group and the Biomedical Research Center (BRC) at Great Ormond Street Hospital.

Immune boosting by B.1.1.529 (Omicron) depends on previous SARS-CoV-2 exposure.

The Omicron, or Pango lineage B.1.1.529, variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carries multiple spike mutations with high transmissibility and partial neutralizing antibody (nAb) escape. Vaccinated individuals show protection against severe disease, often attributed to primed cellular immunity. We investigated T and B cell immunity against B.1.1.529 in triple BioNTech BNT162b2 messenger RNA-vaccinated health care workers (HCWs) with different SARS-CoV-2 infection histories. B and T cell immunity against previous variants of concern was enhanced in triple-vaccinated individuals, but the magnitude of T and B cell responses against B.1.1.529 spike protein was reduced. Immune imprinting by infection with the earlier B.1.1.7 (Alpha) variant resulted in less durable binding antibody against B.1.1.529. Previously infection-naïve HCWs who became infected during the B.1.1.529 wave showed enhanced immunity against earlier variants but reduced nAb potency and T cell responses against B.1.1.529 itself. Previous Wuhan Hu-1 infection abrogated T cell recognition and any enhanced cross-reactive neutralizing immunity on infection with B.1.1.529.

Clinician Perceptions of the Impact of a Shock Team Approach in the Management of Cardiogenic Shock: A Qualitative Study.

INTRODUCTION: Designated cross-specialty shock teams have been proposed as a mechanism to manage the complexity of decision-making and facilitate collaborative, patient-centred care-planning in cardiogenic shock. Observational data support the notion that shock protocols and teams may improve survival, but there is an absence of data interrogating how clinicians engage with and value the shock team paradigm. This study sought to explore clinician perceptions of the value of the shock call system on decision making and the management of CGS. MATERIALS & METHODS: A descriptive qualitative approach was used. A focus group, semi-structured interview was conducted with twelve cross-specialty members of a shock team at a single tertiary cardiac centre in the UK. The focus group was audio-recorded, transcribed, and thematically analysed to capture and describe the clinicians' experience and perceptions of shock team discussions. RESULTS: Eight cardiac intensivists, two heart failure cardiologists, one cardiothoracic surgeon and one interventional cardiologist participated in the focus group. Four key themes were identified from the discussions: supportive decision making; team communication; governance and learning; and future directions. CONCLUSION: This study supports the notion that cross-specialty, real-time patient discussion may provide added value beyond protocolised decision making and account for the complexities of managing patients in a field where definitive, high-quality evidence to guide practice is currently limited.

The impact of organisational change on transfusion practices in perioperative care: an analysis of blood product use following the merger of three London cardiac surgery units to form the Barts Heart Centre.

OBJECTIVES: In 2015, three London cardiac centres, with different transfusion infrastructure support, merged to form the Barts Heart Centre. We describe the impact on transfusion rate, blood usage and interoperator variation. DESIGN: Data was collected on all adult patients undergoing cardiac surgery during 2014 as well as 2016, using the National Institute Cardiovascular Outcomes Research (NICOR) data set. MEASUREMENTS AND MAIN RESULTS: Over the two time periods, a total of 3,647 cardiac procedures were performed (1,930 in 2014 and 1,717 in 2016). There were no significant differences in type of surgery or patient comorbidity between the two epochs of time. Overall, red blood cell transfusion at 24 hours and until hospital discharge reduced significantly in 2016 (odds ratio 0.77; 95% confidence interval 0.68-0.89; p=0.0002). Interoperator variability (adjusted for comorbidities) reduced after merger from standard deviation 0.394 (standard error (SE) 0.096) to 0.269 (SE 0.082), p=0.001. CONCLUSION: Clinical and organisational factors can improve transfusion service.

Sub30: Protocol for the Sub30 feasibility study of a pre-hospital Extracorporeal membrane oxygenation (ECMO) capable advanced resuscitation team at achieving blood flow within 30 ​min in patients with refractory out-of-hospital cardiac arrest.

BACKGROUND: Out-of-hospital cardiac arrest carries a poor prognosis with survival less than 10% in many patient cohorts. Survival is inversely associated with duration of resuscitation as external chest compressions do not provide sufficient blood flow to prevent irreversible organ damage during a prolonged resuscitation. Extracorporeal membrane oxygenation (ECMO) instituted during cardiac arrest can provide normal physiological blood flows and is termed Extracorporeal Cardio-Pulmonary Resuscitation (ECPR). ECPR may improve survival when used with in-hospital cardiac arrests. This possible survival benefit has not been replicated in trials of out-of-hospital cardiac arrests, possibly because of the additional time it takes to transport the patient to hospital and initiate ECPR. Pre-hospital ECPR may shorten the time between cardiac arrest and physiological blood flows, potentially improving survival. It may also mitigate some of the neurological injury that many survivors suffer. METHODS: Sub30 is a prospective six patient feasibility study. The primary aim is to test whether it is possible to institute ECPR within 30 ​min of collapse in adult patients with refractory out of hospital cardiac arrest (OHCA). The secondary aims are to gather preliminary data on clinical outcomes, resource utilisation, and health economics associated with rapid ECPR delivery in order to plan any subsequent clinical investigation or clinical service. On study days a dedicated fast-response vehicle with ECPR capability will be tasked to out-of-hospital cardiac arrests in an area of London served by Barts Heart Centre. If patients suffer a cardiac arrest refractory to standard advanced resuscitation and meet eligibility criteria, ECPR will be started in the pre-hospital environment. DISCUSSION: Delivering pre-hospital ECPR within 30 ​min of an out-of-hospital cardiac arrest presents significant ethical, clinical, governance and logistical challenges. Prior to conducting an efficacy study of ECPR the feasibility of timely and safe application must be demonstrated first. Extensive planning, multiple high-fidelity multiagency simulations and a unique collaboration between pre-hospital and in-hospital institutions will allow us to test the feasibility of this intervention in London. The study has been reviewed, refined and endorsed by the International ECMO Network (ECMONet). TRIAL REGISTRATION: Clinicaltrials. gov NCT03700125, prospectively registered October 9, 2018.

Healthcare Workers Bioresource: Study outline and baseline characteristics of a prospective healthcare worker cohort to study immune protection and pathogenesis in COVID-19.

Background: Most biomedical research has focused on sampling COVID-19 patients presenting to hospital with advanced disease, with less focus on the asymptomatic or paucisymptomatic. We established a bioresource with serial sampling of health care workers (HCWs) designed to obtain samples before and during mainly mild disease, with follow-up sampling to evaluate the quality and duration of immune memory. Methods: We conducted a prospective study on HCWs from three hospital sites in London, initially at a single centre (recruited just prior to first peak community transmission in London), but then extended to multiple sites 3 weeks later (recruitment still ongoing, target n=1,000). Asymptomatic participants attending work complete a health questionnaire, and provide a nasal swab (for SARS-CoV-2 RNA by RT-PCR tests) and blood samples (mononuclear cells, serum, plasma, RNA and DNA are biobanked) at 16 weekly study visits, and at 6 and 12 months. Results: Preliminary baseline results for the first 731 HCWs (400 single-centre, 331 multicentre extension) are presented. Mean age was 38±11 years; 67% are female, 31% nurses, 20% doctors, and 19% work in intensive care units. COVID-19-associated risk factors were: 37% black, Asian or minority ethnicities; 18% smokers; 13% obesity; 11% asthma; 7% hypertension and 2% diabetes mellitus. At baseline, 41% reported symptoms in the preceding 2 weeks. Preliminary test results from the initial cohort (n=400) are available: PCR at baseline for SARS-CoV-2 was positive in 28 of 396 (7.1%, 95% CI 4.9-10.0%) and 15 of 385 (3.9%, 2.4-6.3%) had circulating IgG antibodies. Conclusions: This COVID-19 bioresource established just before the peak of infections in the UK will provide longitudinal assessments of incident infection and immune responses in HCWs through the natural time course of disease and convalescence. The samples and data from this bioresource are available to academic collaborators by application  https://covid-consortium.com/application-for-samples/.

Discordant neutralizing antibody and T cell responses in asymptomatic and mild SARS-CoV-2 infection.

Understanding the nature of immunity following mild/asymptomatic infection with SARS-CoV-2 is crucial to controlling the pandemic. We analyzed T cell and neutralizing antibody responses in 136 healthcare workers (HCW) 16-18 weeks after United Kingdom lockdown, 76 of whom had mild/asymptomatic SARS-CoV-2 infection captured by serial sampling. Neutralizing antibodies (nAb) were present in 89% of previously infected HCW. T cell responses tended to be lower following asymptomatic infection than in those reporting case-definition symptoms of COVID-19, while nAb titers were maintained irrespective of symptoms. T cell and antibody responses were sometimes discordant. Eleven percent lacked nAb and had undetectable T cell responses to spike protein but had T cells reactive with other SARS-CoV-2 antigens. Our findings suggest that the majority of individuals with mild or asymptomatic SARS-CoV-2 infection carry nAb complemented by multispecific T cell responses at 16-18 weeks after mild or asymptomatic SARS-CoV-2 infection.

New-Onset Atrial Fibrillation in Adult Patients After Cardiac Surgery.

PURPOSE OF REVIEW: An overview of recent literature regarding pathophysiology, risk factors, prophylaxis, and treatment of new-onset atrial fibrillation (AF) in post-cardiac surgical patients. RECENT FINDINGS: AF is the most frequent adverse event after cardiac surgery with significant associated morbidity, mortality, and financial cost. Its causes are multifactorial, and models to stratify patients into risk categories are progressing but a consistent, evidence-based system has not yet been developed. Pharmacologic and surgical interventions to prevent and treat this complication have been an area of ongoing research and recent societal guidelines reflect this. SUMMARY: Inconsistencies remain surrounding how to best identify higher-risk AF patients, which interventions should be used to prevent and treat AF, and which patient groups should receive these interventions. The evidence for these available strategies and their place in contemporary guidelines are summarized.

A pragmatic pilot phase II randomised controlled trial of prothrombin complex concentrates (PCC) versus fresh frozen plasma (FFP) in adult patients who are undergoing heart surgery (PROPHESY).

BACKGROUND: Fresh frozen plasma (FFP) is the accepted standard treatment for clotting factor replacement in bleeding patients during or immediately after cardiac surgery. In the United Kingdom prothrombin complex concentrate (PCC) is not licensed in this setting, although it is being used in Europe because it has a higher concentration of clotting factor levels, and it can be administered rapidly and in small volume, resulting in less volume overload during cardiac surgery. METHODS: PROPHESY is a pragmatic, single-centre, open-label, randomised, controlled pilot trial that will assess whether it is feasible to perform a large trial in the future that will compare PCC versus FFP in patients who are bleeding (not on warfarin) and who require blood transfusion. Over a 15-month period, 50 patients will be randomised to PCC versus FFP if they develop active bleeding within 24 h of cardiac surgery and for whom the clinician has decided to administer FFP for treatment of bleeding. Standard laboratory and point-of-care assessments will be performed as per routine practice, and additional research blood samples will be taken at three time points to assess haemostasis. Subjects will be assessed daily up to hospital discharge or 30 days or death (whichever occurs first) and will be seen in follow-up for 90 days after surgery to assess for thromboembolic complications and hospital re-admission since discharge. Quality-of-life assessment will be performed pre-surgery and at 90 days post-surgery. We will also perform qualitative research with clinical experts and patients to explore the understanding of and experience with the interventions, as well as adherence to study procedures and protocol. DISCUSSION: There have been no randomised controlled trials that have compared the safety and efficacy of FFP versus PCC in cardiac surgery patients who are bleeding. This pilot study will assess if individual components of a large trial are deliverable to assess the safety and efficacy of the two blood products in the future. TRIAL REGISTRATION: EudraCT, 2018-003041-41; ClinicalTrials.gov, NCT03715348. Registered on 29 July 2018.

Evaluating ballot initiative support for legalised marijuana: The case of Washington.

BACKGROUND: In 2012, Washington and Colorado became the first U.S. states to legalise recreational marijuana. By 2016, eight states and the District of Columbia had legalised recreational marijuana, with more expected to consider it in 2018. Despite this trend, little academic research explains what drives ballot-initiative vote choice on marijuana legalisation. METHODS: This paper uses a pre-election random sample voter survey to examine the individual characteristics that correlated with Washington voters' support for legal recreational marijuana. RESULTS: We find that voting on marijuana ballot initiatives largely reflects public opinion about marijuana and is particularly shaped voters' political ideology, party affiliation, religious affiliation and practice, and education. Notably, we find that those reporting experiences (i.e., someone they know) with the criminal justice system are more supportive of legalisation than those who do not. CONCLUSION: We conclude that marijuana legalisation voting behavior generally aligns with public opinion on the issue. However, one key aspect of Washington's legalisation campaign-the criminal injustices of marijuana illegality-helped shape Washington state voting behavior. Further research is needed to examine if, when, and in what contexts criminal justice campaign themes are likely to strengthen or undermine future states' marijuana legalisation efforts.