Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

The effects of diabetes clubs on peer-support, disclosure of diabetes status, and sources of information regarding diabetes management: results of a pilot-intervention in rural Vietnam

OBJECTIVES

To measure the effects of diabetes clubs on peer support, disclosure of diabetes status, and the source of information regarding the management of diabetes among persons living with type-2 diabetes (T2D) in rural Vietnam.

STUDY DESIGN

A pre- and post-pilot intervention study was carried out in Thai Binh Province, Vietnam (n = 222).

RESULTS

Post-intervention, 57.7 % reported using experiences shared by other persons with T2D during the diabetes club sessions. Compared to pre-intervention, there was an increase in the proportion of persons with T2D who disclosed their diabetes status to friends and/or community members (an increase of 15.3 and 13.8 percentage points, respectively). The proportion of persons who reported gathering their own information regarding diabetes management without any support from others decreased from 15.7 % to 6.3 %. Those who reported a relative inside their home or a relative outside their household as their primary source of T2D-relevant information increased from 10.8 % to 18.6 % and from 2.7 % to 9.5 %, respectively. Persons who mentioned that they did not have a need for further support for their diabetes care increased from 18.5 % to 32.0 %. Specific support regarding diabetes-related knowledge received from family members, friends, and/or community members increased from 27.5 % to 62.2 % CONCLUSIONS: These findings suggest a promising potential for the implementation of diabetes clubs to enhance diabetes-relevant knowledge and the quality of self-management among persons living with T2D diabetes in rural areas of Vietnam.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector

This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139  fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst)  fb, to be compared with the standard model prediction of 515_{-42}^{+36}  fb at next-to-leading order in QCD.

The interplay between the impact of household's and children's education on the risk of type 2 diabetes and death among older adults: a Danish register-based cohort study

OBJECTIVES

This study aims to assess the association of household's and children's education on the risk of type 2 diabetes (T2D) and subsequent death.

STUDY DESIGN

Danish register-based cohort study.

METHODS

In total, 1,021,557 adults were included at their 65th birthday between 2000 and 2018. A multistate survival model was performed to estimate the association of household's and children's education on the transition between the three states: 1) 65th birthday; 2) diagnosis of T2D; and 3) all-cause death.

RESULTS

The incidence rates per 1000 person-years were 9.1 for T2D, 18.4 for death without T2D, and 45.0 for death with T2D. Compared to long household's education and children's education, long household's education combined with either short-medium children's education or no children were associated with a 1.49- (95% confidence interval [CI]: 1.44; 1.54] and 1.69-times (95% CI: 1.61;1.78) higher hazard of T2D, respectively. Short-medium household's education combined with either long children's education or no children were associated with 0.64- (95% CI: 0.62; 0.66) and 0.77-times (95% CI: 0.74; 0.79) lower hazard of T2D, respectively. Compared to long household's education and children's education, any other combination of household's and children's education was associated with higher hazards of death both without and with T2D.

CONCLUSION

Older adults living in households with long education with no children or children with short-medium education had higher hazards of T2D. Households with short-medium education and no children or children with long education were associated with lower hazards of T2D. Both household's and children's education were associated with higher hazard of death without and with T2D.

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb^{-1} and 257  pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ-Lepton Anomalous Magnetic Moment with the ATLAS Detector

This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment a_{τ}. The dataset corresponds to an integrated luminosity of 1.44  nb^{-1} of LHC Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of μ_{ττ}=1.03_{-0.05}^{+0.06} assuming the standard model value for a_{τ}. To measure a_{τ}, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→μμ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for a_{τ} is -0.057 Collapse

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Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS

Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including pp and p+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36  nb^{-1} of p+Pb and 3.6  pb^{-1} of pp collisions at 5.02 TeV. The yields of charged hadrons with p_{T}^{ch}>0.5  GeV near and opposite in azimuth to jets with p_{T}^{jet}>30 or 60 GeV, and the ratios of these yields between p+Pb and pp collisions, I_{pPb}, are reported. The collision centrality of p+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I_{pPb} values are consistent with unity within a few percent for hadrons with p_{T}^{ch}>4  GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p+Pb collisions.

Search for Heavy Neutral Leptons in Decays of W Bosons Using a Dilepton Displaced Vertex in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector

A search for a long-lived, heavy neutral lepton (N) in 139  fb^{-1} of sqrt[s]=13  TeV pp collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The N is produced via W→Nμ or W→Ne and decays into two charged leptons and a neutrino, forming a displaced vertex. The N mass is used to discriminate between signal and background. No signal is observed, and limits are set on the squared mixing parameters of the N with the left-handed neutrino states for the N mass range 3  GeV Collapse

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Test of CP Invariance in Higgs Boson Vector-Boson-Fusion Production Using the H→γγ Channel with the ATLAS Detector

A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139  fb^{-1} of proton-proton collision data at sqrt[s]=13  TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.

Coronary artery disease is a stronger predictor of mortality than left ventricular ejection fraction among newly diagnosed patients with heart failure

Background

Heart failure (HF) prevalence remains high and prognosis is poor despite improvements in both medical treatment and implantation of primary prophylactic implantable cardioverter-defibrillator (ICD) and cardiac resynchronisation therapy (CRT) devices. At present, classification of HF and treatment algorithms are determined by the left ventricular ejection fraction (LVEF). However, in patients with LVEF <50% and newly diagnosed HF, evidence remains sparse as to whether LVEF per se or presence of CAD provide independent prognostic information on mortality.

Methods

Using the Western Denmark Heart Registry, we identified newly diagnosed patients with HF and LVEF 10–49% undergoing first-time coronary angiography (CAG) from 2003 to 2016 referred due to HF. Patients were stratified by LVEF (10–35% vs. 36–49%, according as to whether primary prophylactic ICD and CRT treatment should be considered) and presence of coronary artery disease (CAD). Maximum follow-up was 10 years. We estimated 10-year cumulative incidence of death and calculated hazard ratios (HR) adjusted for relevant comorbidities and risk factors.

Results

Of 154,186 Western Danish residents undergoing CAG, 3,620 patients had HF and LVEF 10–49%. Among these, 2,780 (77%) patients had LVEF 10–35% and 840 (23%) patients had LVEF 36–49%. CAD was present in 1,592 (44%) patients.

There was a potential association in 10-year mortality when comparing patients with HF and LVEF 36–49% to those with LVEF 10–35% (37.3% vs. 42.1%, HR 1.15; 95% CI 0.99–1.34) (Figure 1A), with point estimates of mortality ranging from being 1% reduced to 24% increased. This result was not strongly influenced by the presence of CAD (HR 1.11; 95% CI 0.91–1.35) or absence of CAD (HR 1.24; 95% CI 0.97–1.57) (Figure 1B). There was no trend between LVEF categorized by 5-percentiles and mortality (p for trend = 0.24) (Table 1). In contrast, CAD was more strongly associated with increased 10-year mortality (55.0% vs. 31.5%, HR 1.43; 95% CI 1.25–1.64) irrespective of LVEF (Figure 1B).

Conclusion

Among newly diagnosed patients with HF and LVEF 10–49%, presence of CAD impacts mortality substantially more than LVEF per se. These results emphasize that assessment of CAD is pivotal for prognostication of newly diagnosed patients with HF and LVEF 10–49%.

Funding Acknowledgement

Type of funding sources: None.

Risk of lead explantation after first-time implantation of cardiac implantable electronic device as a function of comorbidity: a nationwide study

Background

The benefit of cardiac implantable electronic devices (CIEDs) is challenged by the risk of procedure-related complications and lead explantation. Whether patient comorbidity burden is associated with risk of lead explantation <6 months of implantation is unknown.

Purpose

We assessed the risk of lead explantation and its association with comorbidity burden within 6 months after first-time CIED implantation.

Methods

The study population comprised patients ≥18 years old with first-time CIED implantation (i.e., pacemaker [PM], implantable cardioverter defibrillator [ICD], and cardiac resynchronisation therapy with defibrillator [CRT-D] or without [CRT-P]) using Danish nationwide registries including the Danish Pacemaker and ICD registry (1 January 2000 to 30 June 2018). Patients were followed from their first-time CIED implantation and 6 months forward. Patient comorbidity burden was categorised in four groups according to the Charlson Comorbidity Index (CCI) score: 0 (none), 1–2 (mild), 3–4 (moderate), and ≥5 (severe). Multivariable cause-specific Cox regression was performed to assess risk of lead explantation according to comorbidity burden, with death as competing risk. Comorbidity burden was adjusted for sex, age, type of CIED, and body mass index categories.

Results

We identified 73,491 patients with first-time CIED implantation including 55,733 (75.8%) with PM, 11,351 (15.5%) with ICD, 2,989 (4.1%) with CRT-P, and 3,418 (4.7%) with CRT-D. In total, 1,049 (1.4%) patients underwent lead explantation. The median age of the study population was 75.1 years [25th-75th percentile 66.2–82.5 years], and 62.1% were male. Patients undergoing lead explantation had higher median CCI score, compared with those not undergoing lead explantation (2 [1–3] and 1 [0–3], respectively). The median age and distribution of sex were similar in both groups. In the multivariable Cox regression model (Figure 1), an increase in patient comorbidity burden was associated with higher hazard ratio [HR] of lead explantation, compared with CCI score 0 (CCI score 1–2: HR=1.38 [95% confidence interval [CI]: 1.12–1.69], CCI score 3–4: HR=1.61 [95% CI: 1.28–2.03], and CCI score ≥5: HR=1.60 [95% CI: 1.25–2.05]).

Conclusion

Risk of lead explantation within 6 months after first-time implantation of cardiac implantable electronic device was 1.4% and associated with higher comorbidity burden.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Independent Research Fund Denmark

Staphylococcus aureus bacteremia in Danish patients with cardiac implantable electronic devices: an explorative epidemiological study

Background

Device-related infection is the most common serious complication in patients with cardiac implantable electronic devices (CIED). Staphylococcus aureus accounts for up to 30% of CIED-related infections. There is a lack of scientific literature investigating risk of Staphylococcus aureus bacteremia (SAB) in CIED-patients.

Purpose

We aimed to describe the risk of SAB in Danish patients with a CIED through the years 2000–2018 compared to the background population.

Methods

Patients who received a CIED from 2000–2018 were identified from The Danish National Pacemaker and ICD Register. Patients were matched 1:5 on age and gender with the background population. We identified the primary endpoint of first time SAB from The National Danish Staphylococcus Aureus Bacteremia Database. The cumulative incidence of SAB was calculated using the Aalen-Johansen estimator, adding competing risk of death into account. Hazard ratios were estimated by Cox regression models adjusting for age and gender. Crude rates of relapse SAB, defined as a new SAB episode 14–180 days after first SAB, and device extractions were reported for all patients who survived 14 days from SAB diagnosis.

Results

We identified 79,324 CIED-patients (pacemaker (PM) = 61,227; Implantable Cardioverter Defibrillator (ICD) = 11,635; Cardiac resynchronization therapy, PM or ICD (CRT) = 6,364 and 396,590 matched controls (median age 75.5±13.3 years; 61% males). Age and gender distribution differed significantly by device type (age: PM 76.1±12.1; ICD 62.4±13.4; CRT 68.0±11.1; males: PM: 55.6%, ICD% 75.5: CRT: 80.9%). Across a mean follow-up of 5.9 (±4.6) years, we observed first episode of SAB in 1,430 (1.8%) CIED-patients, compared to 2,599 (0.7%) patients in the control population (p<0.001).

The 10-year cumulative incidence of SAB was 1.0% for controls and 2.2% for CIED patients. The risk of SAB differed substantially by device type (Figure 1). Compared to controls and adjusted for age and gender, increasing hazard ratios for SAB were observed with more advanced devices: PM 1.12 (1.11–1.13); ICD 1.36 (1.33–1.39); CRT 1.55 (1.51–1.59). However, CIED-patients with SAB did not have higher 30-day mortality rates than the non-CIED control population with SAB (Controls 34.8%; PM 35.1%; ICD 28.1% CRT 26.1%, p=0.016). Out of all SAB patients who survived 14 days from SAB diagnosis (Controls=1,672; CIED=1,107), relapse SAB occurred in 52 (3.1%) controls and in 51 (4.6%) CIED-patients (PM 4.0%; ICD 5.8%; CRT 6.3%). Device extraction within 14 and 30 days from SAB diagnosis was undertaken in less than 30% of the CIED-patients (PM: 11.3/13.6%; ICD: 22.7/27.5%; CRT: 17.4/20.1%).

Conclusion

The occurrence of SAB was higher in CIED patients compared with controls and increased with more advanced devices. There was no difference in 30-day mortality after SAB between CIED patients and controls. Relapse SAB occurred in less than 7%, despite a low percentage of early device extractions.

Funding Acknowledgement

Type of funding sources: None.

Long-term risk of replacement of cardiovascular implantable electronic devices following external cardioversion

Introduction

External cardioversion (ECV) with transthoracic shock is a recommended and important part of the rhythm control strategy regardless of cardiovascular implantable electronic devices (CIED). Studies and case reports have demonstrated rare, but serious CIED malfunctions related to the ECV procedure. However, follow-up data on contemporary CIEDs undergoing ECV procedures are limited. The aim of this study is to investigate the long-term risk of generator replacements following an ECV procedure.

Methods

All CIED implants and surgical re-interventions in Denmark were identified in the Danish Pacemaker and ICD Register from January 2005 to April 2021. The ECV procedures were identified in the Danish National Patient Registry from January 2010 to February 2019. For each patient undergoing ECV, five matched (age, sex, and type of CIED) controls without previous ECV were identified. Time to generator replacement was estimated using competing risk analyses, with death, extraction and up-/down-grade being competing events. Risks were estimated by the pseudo-observation method.

Results

We identified in total 3,924 ECV-events in 2,610 CIED patients with 74.4% male. Mean age of patients at first ECV-procedure were 68.6±11.7 years, and median implant time was 1.5 year. The type of CIED included 50% of pacemakers, 28% of Implantable Cardioverter Defibrillators, and 22% of Cardiac Resynchronization Therapy-systems. During the first 5 years of follow-up, 451 (17.3%) of the shock-exposed devices were replaced vs. 2,000 (15.2%) of the unexposed devices. The relative risks (RR) of device replacement were 1.43 (95% CI: 0.5; 2.4) after 12 months, 1.44 (95% CI: 0.1; 2.8) after 24 months, and −0.53 (95% CI: −2.8; 1.7) after 5 years. The cumulated incidence of first endpoint: Replacement, death, extraction, and up-/down-grade are illustrated in Figure 1. A larger proportion of patients died in the shock-exposed group with n=427 (16.4%) compared to n=1,588 (12.2%) in the unexposed group during 5-years of follow-up with RR=3.2 (95% CI: 1.2; 5.3) of dead before other events.

Conclusion

Contemporary CIEDs do not indicate different risk of generator replacement following external cardioversion with transthoracic shocks. Shock-exposed device patients were more prone for extraction and death.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): This is work was financed by Department of Cardiology, Aalborg University Hospital and supported by Karl G. Andersen foundation.

Cardiac resynchronisation therapy and implantable cardioverter-defibrillator in non-ischaemic systolic heart failure: extended follow-up of the DANISH trial

Background

In the Danish Study to Assess the Efficacy of Implantable Cardioverter-Defibrillators [ICDs] in Patients with Non-ischaemic Systolic Heart Failure on Mortality (DANISH) trial, ICD implantation did not provide an overall survival benefit in patients with non-ischaemic systolic heart failure. A high proportion of patients in the DANISH trial received a cardiac resynchronisation therapy (CRT) device, which improves the prognosis in patients with heart failure. Therefore, it is of interest to examine whether the effect of ICD implantation in patients with non-ischaemic systolic heart failure is modified by CRT.

Purpose

Adding 4 years of additional follow-up to the DANISH trial, we examined the effect of ICD implantation according to status with respect to CRT implantation at baseline.

Methods

In the DANISH trial, 556 patients with non-ischaemic systolic heart failure were randomised to receive an ICD and 560 to receive usual clinical care (control). Patients fulfilling indications for a CRT device received a CRT-defibrillator (if randomised to ICD arm) or CRT-pacemaker (if randomised to control arm). In the ICD group, 322 patients (57.9%) received a CRT device; in the control group, 323 patients (57.7%) received a CRT device. In this extended follow-up study, patients were followed until May 18, 2020. The primary outcome was death from any cause; secondary outcomes were cardiovascular death and sudden cardiovascular death.

Results

During a median follow-up of 9.5 years, the ICD group did not have significantly lower all-cause mortality compared with the control group (hazard ratio [HR] 0.89 [95% CI, 0.74–1.08]). The results were independent of whether the patient received a CRT device at randomisation (patients with a CRT device: HR 0.92 [95% CI, 0.72–1.18]; patients without a CRT device: HR 0.86 [95% CI, 0.64–1.14]; P for interaction, 0.72). Similarly, ICD implantation did not reduce rates of cardiovascular death overall (HR 0.87 [95% CI, 0.70–1.09]), and this association was not modified by CRT (patients with a CRT device: HR 0.89 [95% CI, 0.66–1.19]; patients without a CRT device: HR 0.85 [95% CI, 0.60–1.20]; P for interaction, 0.86). The ICD group had significantly lower rates of sudden cardiovascular death in the overall population (HR, 0.60 [95% CI, 0.40–0.92]), and this association was not modified by CRT (patients with a CRT device: HR 0.69 [95% CI, 0.40–1.21]; patients without a CRT device: HR 0.51 [95% CI, 0.26–0.97]; P for interaction, 0.47). See Figure 1 for all results.

Conclusions

In this extended follow-up study of the DANISH trial, the effect of ICD implantation in patients with non-ischaemic systolic heart failure was not modified by CRT.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The DANISH trial was supported by unrestricted grants from Medtronic, St Jude Medical, Tryg Fonden, and the Danish Heart Foundation. No further funding was obtained for this follow-up study.

Adipose tissue, bile acids, and gut microbiome species associated with gallstones after bariatric surgery

Several risk factors are associated with gallstone disease after bariatric surgery, but the underlying pathophysiological mechanisms of gallstone formation are unclear. We hypothesize that gallstone formation after bariatric surgery is induced by different pathways compared to gallstone formation in the general population, since postoperative formation occurs rapidly in patients who did not develop gallstones in preceding years. To identify both pathophysiological and potentially protective mechanisms against postoperative gallstone formation, we compared the preoperative fasting metabolome, fecal microbiome, and liver and adipose tissue transcriptome obtained before or during bariatric surgery of obese patients with and without postoperative gallstones. In total, 88 patients were selected from the BARIA longitudinal cohort study. Within this group, 32 patients had postoperative gallstones within two years. Gut microbiota metagenomic analyses showed group differences in abundance of 41 bacterial species, particularly abundance of Lactobacillaceae and Enterobacteriaceae in patients without gallstones. Subcutaneous adipose tissue transcriptomic analyses revealed four genes that were suppressed in gallstone patients compared to patients without gallstones. These baseline gene expression and gut microbiota composition differences might relate to protective mechanisms against gallstone formation after bariatric surgery. Moreover, baseline fasting blood samples of patients with postoperative gallstones showed increased levels of several bile acids. Overall, we revealed different genes and bacteria associated with gallstones than those previously reported in the general population, supporting the hypothesis that gallstone formation after bariatric surgery follows a different trajectory. Further research is necessary to confirm the involvement of the bile acids, adipose tissue activity, and microbial species observed here.

Observation of WWW Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WWW production and a measurement of its cross section using 139  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from WWW production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive WWW production cross section is measured to be 820±100 (stat)±80 (syst)  fb, approximately 2.6 standard deviations from the predicted cross section of 511±18  fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy.

A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery

The standard model of particle physics1-4 describes the known fundamental particles and forces that make up our Universe, with the exception of gravity. One of the central features of the standard model is a field that permeates all of space and interacts with fundamental particles5-9. The quantum excitation of this field, known as the Higgs field, manifests itself as the Higgs boson, the only fundamental particle with no spin. In 2012, a particle with properties consistent with the Higgs boson of the standard model was observed by the ATLAS and CMS experiments at the Large Hadron Collider at CERN10,11. Since then, more than 30 times as many Higgs bosons have been recorded by the ATLAS experiment, enabling much more precise measurements and new tests of the theory. Here, on the basis of this larger dataset, we combine an unprecedented number of production and decay processes of the Higgs boson to scrutinize its interactions with elementary particles. Interactions with gluons, photons, and W and Z bosons-the carriers of the strong, electromagnetic and weak forces-are studied in detail. Interactions with three third-generation matter particles (bottom (b) and top (t) quarks, and tau leptons (τ)) are well measured and indications of interactions with a second-generation particle (muons, μ) are emerging. These tests reveal that the Higgs boson discovered ten years ago is remarkably consistent with the predictions of the theory and provide stringent constraints on many models of new phenomena beyond the standard model.

A webbased intervention for patients with an implantable cardioverter defibrillator, a qualitative study of nurses experiences

Funding Acknowledgements

Type of funding sources: None.

Background

Implantable cardioverter defibrillator (ICD) therapy is the gold standard for prevention of sudden cardiac death. Patients generally adapt well to living with an ICD, but 20% have difficulties adjusting, with increased risk of anxiety and depression and decreased quality of life. New web-based interventions engaging patients with an ICD might be efficient, but there is sparse knowledge on experiences with web-based care from the perspective of cardiac nurses.

Purpose

The aim of the study was to explore cardiac nurses’ experiences with a web-based intervention designed to empower patients with an ICD.

Methods

We conducted a qualitative study based on semi-structured interviews. The informants (n=9) were experienced cardiac nurses across 5 Danish university hospitals. They were delivering a comprehensive web-based intervention for patients with an ICD, including patient education, chats, monitoring of anxiety and depression and a patient forum. The intervention was tested in a randomized controlled trial. The interviews were transcribed verbatim, coded and analyzed using qualitative content analysis with NVivo software.

Results

We identified an overall theme: "Between traditional nursing and modern eHealth". The theme emerged from six categories, each covering three or four subcategories (Figure 1). The categories were: (1) comprehensive intervention, (2) patient-related differences in engagement, (3) following the protocol is a balancing act, (4) online communication challenges patient contact, (5) professional collaboration varies, and (6) an intervention with potential. Cardiac nurses were in general positive towards the concept of this web-based intervention and believe it holds a large potential. On the other hand, they were challenged by not establishing a personal relation and by losing face-to-face contact with patients, which they found valuable for getting a feeling for patients’ wellbeing and potential mental health issues. Ensuring face-to-face contact by either starting the intervention with a personal contact or including the possibility of video contacts might enhance the value of web-based interventions from the perspective of cardiac nurses. The nurses found the intervention especially suitable for patients who had suffered a cardiac arrest.

Conclusion

Specific training in eHealth communication is necessary as web-based care entails a shift in nursing role and a new format of communication for cardiac nurses. Future evaluations of web-based cardiac rehabilitation interventions in clinical practice are needed to assess the potential impact in "real-life" cardiac care.

Cardiac surgery in cardiac implantable electronic device patients and risk of device infections: a nationwide nested case-control study

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Karen Elise Jensen’s Foundation

Background

Cardiac surgery in patients with cardiac implantable electronic devices (CIEDs) has been associated with a higher risk of infective endocarditis, but how it influences risk of CIED-specific infections is not known.

Purpose

To examine risk of systemic CIED infections after cardiac surgery in patients with CIEDs.

Methods

Based on data obtained from Danish administrative registries and the Danish Pacemaker and ICD Register, we conducted a case-control study nested within a nationwide cohort of patients who underwent a de novo CIED implantation in Denmark between 1998-2017. Patients entered the study at six months after implantation. We defined cases as incident systemic CIED infections resulting in device system extraction. Controls were sampled 1:100 on age, sex and follow-up time using risk set sampling. Exposure was defined as coronary artery bypass graft (CABG)-, or cardiac heart valve replacement- or repair surgery.

Results

From a study cohort comprising 67,621 patients, we identified 170 cases and 16,966 controls. In the minimally adjusted model, the incidence rate ratio (IRR) for systemic CIED infection was 6.4 (95% confidence interval (CI) 3.9-17.1) with cardiac surgery, and after confounder adjustment, 7.0 (95% CI 4.1-11.9). IRRs were higher when exposure was restricted to heart valve replacement surgery (adjusted IRR (aIRR) 9.7, 95% CI 5.2-17.8), and when limiting our exposure time window to one year (aIRR 12.7, 95% CI 5.8-27.8).

Conclusion

Cardiac surgery in patients with de novo CIEDs was associated with a high risk of systemic CIED infections. Highest risk was observed after heart valve replacement surgery, and within the first year of surgery.

Early mortality and complications following first-time catheter ablation of atrial fibrillation in a nationwide cohort

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is the most common clinical arrhythmia. Pulmonary vein isolation (PVI) by catheter ablation has become a cornerstone in the treatment of AF. Serious complications to PVI have been reported to be at an acceptable level and risk of death after AF ablation is low.

Purpose

In a contemporary nationwide cohort of patients undergoing first-time PVI by catheter ablation, we wanted to investigate the 30-day mortality after ablation, and to examine risk and potential risk factors of PVI-related complications.

Methods

Population-based cohort study in patients who underwent first-time PVI by catheter ablation between 2011-2018 identified from the National Danish Ablation Registry. Primary outcome was early post-procedural mortality, defined as death of any cause within 30 days of index PVI procedure, or in connection to a hospitalization started within 30 days. Secondary outcomes were all-cause rehospitalization and complication, including postoperative infection, cardiac, vascular, neurological, vascular, and pulmonary complications within 30 days. Data on mortality and complications were collected from national health and administrative registries. Binary regression was used to estimate risk ratio (RR) with 95% confidence intervals (CI) for association between selected predictors and any complication, and adjusted gender, age, BMI, prior ablation, calendar period (ablation from 2011-2013, 2014-2016, and >2016).

Results

We included 8560 patients. Median age was 62, 66% were men, 12% had a history of heart failure, and median CHA2DS2VASc score was 1 (Interquartile range [IQR]; 1-2). Charlton Comorbidity index (CCI) was none in 66%, moderate in 29% and severe in 5%. A total of 10 (0.12%) patients died within 30 days of ablation, of which 4 patients died during initial hospitalization. Median time to death was 20 (IQR, 12 to 29) days. Patients who died were more likely to have experienced a procedure-related complication (40% vs. 4%, P<0.001). Procedure-related complications occurred in 298 (3.5%), and the risk was 4.4%, 3.0% and 3.3% in the time periods between 2011-2013, 2014-2016 and >2016, respectively. Most common complications were postoperative infection (26%), cardiac complication (26%), and vascular complications (18%). Complication risk was increased in patients with higher age (aRR, 65-74 year; 1.67 [1.32-2.11] and >74 years; 2.48 [1.60-3.84]), moderate CCI (aRR 1.45 [1.14-1.83]), cardiovascular disease (aRR 1.52 [1.09-2.11]) and antithrombotic treatment (aRR 1.41 [1.05-1.89]). After first-time PVI, 1.963 (23%) patients were re-hospitalized within 30 days, and most common primary discharge diagnoses were AF (87%) and direct cardioversion was performed in 765 (39%) patients.

Conclusion

In a nationwide cohort of patients who underwent first-time PVI, number of deaths within 30 days of ablation was low (0.12%). Risk of complication was low and 23% of the patients were re-hospitalized within 30 days.

Lead complications after cardiac surgery in danish patients with cardiac implantable electronic devices: a nationwide nested case-control study

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Karen Elise Jensen’s Foundation

Background

Manipulation of the heart during cardiac surgery in patients with cardiac implantable electronic devices (CIEDs) may result in lead damage or -displacement, but whether cardiac surgery truly infers an excess risk of lead failure is not known.

Purpose

The objective of this study was to examine risk of lead complications as a result of cardiac surgery in CIED patients.

Methods

We conducted a nationwide nested case-control study. Our source population comprised all patients ≥18 of age who underwent a de novo CIED implantation in Denmark between 1998 and 2017. Only patients who were alive and event-free at six months after implantation were eligible for inclusion in the case-control study. Cases were defined as incident lead complications resulting in a revision procedure, and were matched 1:30 to controls using risk set sampling. We used conditional logistic regression to estimate incidence rate ratios (IRRs) for the association between cardiac surgery and lead complications.

Results

Our population consisted of 61,869 de novo CIED patient. We identified 1324 incident cases of lead complications and 39,708 time-matched controls. 1036 cases and controls underwent cardiac surgery during follow-up; 61 cases (4.5%) and 975 controls (2.5%). Risk of lead-related reoperation was highest within the first six months of cardiac surgery (IRR 10.1, 95% CI 6.5-15.6, adjusted IRR 11.0, 95% CI 7-17.4). At one year, we observed no association between cardiac surgery and lead complications (IRR: 1.0, 95% CI 0.7-1.5 and adjusted IRR: 1.1, 95% CI 0.7-1.6).

Conclusion

Cardiac surgery was associated with a substantial risk of lead complications in patients with de novo CIEDs. Manipulation of the heart including cannulation of the right atrium is a likely explanation for the subsequent lead problems.

Magnetic resonance imaging in patients with temporary external pacemakers

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): This work was supported by Aarhus University, the Danish Heart Foundation (grant number R140-A9482-B2407); Health Research Foundation of Central Denmark Region (grant number R64-A3194-B1667); and Gangstedfonden.

Background

Magnetic resonance imaging (MRI) is increasingly becoming the imaging modality of choice for many clinical disorders. According to guidelines, MRI can safely be performed 6 weeks after implantation of a MRI-conditional permanent pacemaker. However, there is no recommendations and only very limited evidence regarding MRI in patients treated with temporary external pacemakers. Such patients thus may be denied the opportunity for well-indicated MRI.

Purpose

To describe safety and feasibility of MRI in patients with temporary external pacemakers.

Method

We reviewed patient records of all patients treated with temporary external pacing between 2016 and 2020 at a tertiary centre. Temporary pacing was established using a transvenous standard active fixation pacing lead inserted percutaneously and connected to a MRI-conditional pacemaker taped to the skin. Information on baseline characteristics, indication, days of hospital and pacemaker function before and after MRI was gathered. Before MRI, devices were programmed according to guidelines for permanent pacemakers and the device was fixated to avoid movement due to the magnetic field of the MRI system. Patients were monitored during MRI. Values are reported as N (%), and continuous variables are presented as median (interquartile range [IQR]) or mean ± SD.

Results

A total of 827 patients received a temporary pacemaker. MRI was performed in 44 (5%) patients. Mean age was 71 ­± 13 years and 13 (30%) were females. Indication for temporary device were atrioventricular block (20 [45%]), aborted cardiac arrest (9 [21%]), infective endocarditis (9 [21%]), and other (6 [14%]). MRI was performed to rule out or confirm structural heart disease (16 [36%]), cerebral disease (9 [20%]), spondylodiscitis (7 [16%]), or other (12 [27%]), which was not able to do with other imaging modalities. Cardiac MRI was performed in 22 (50%) patients, while MRI of cerebrum, spine, abdomen, and lower extremities were performed in the remaining patients. Median (IQR) time from implantation of the temporary device to MRI was 6 (3–11) days. During MRI, we observed no device-related malfunction or arrhythmia. Nor did we detect any change in lead sensing, impedance, or pacing threshold. A final diagnosis was confirmed in 27 (61%) patients after MRI. However, MRI provided information to guide the clinical management in all cases without artifacts compromising the diagnostic image quality. Instead of a dual chamber pacemaker, 7 (22%) patients had implanted a cardiac resynchronization therapy and/or implantable cardioverter defibrillator due to the MRI diagnosis. A permanent pacemaker was implanted in 32 (73%) patients within median (IQR) 12 (7–23) days after temporary pacing was established.

Conclusion

MRI is feasible and safe in patients with temporary external pacing established with a regular MRI-conditional device and a standard active fixation lead. The MRI was helpful in determining type of permanent device.

Search for Lepton-Flavor Violation in Z-Boson Decays with τ Leptons with the ATLAS Detector

A search for lepton-flavor-violating Z→eτ and Z→μτ decays with pp collision data recorded by the ATLAS detector at the LHC is presented. This analysis uses 139  fb^{-1} of Run 2 pp collisions at sqrt[s]=13  TeV and is combined with the results of a similar ATLAS search in the final state in which the τ lepton decays hadronically, using the same data set as well as Run 1 data. The addition of leptonically decaying τ leptons significantly improves the sensitivity reach for Z→ℓτ decays. The Z→ℓτ branching fractions are constrained in this analysis to B(Z→eτ)<7.0×10^{-6} and B(Z→μτ)<7.2×10^{-6} at 95% confidence level. The combination with the previously published analyses sets the strongest constraints to date: B(Z→eτ)<5.0×10^{-6} and B(Z→μτ)<6.5×10^{-6} at 95% confidence level.

Dynamic changes of cardiovascular biomarkers after ablation for atrial fibrillation: observations from AXAFA-AFNET5

Background

The dynamic changes and stability of blood biomarkers over time and after treatment are not well known. In this study, we describe changes in 12 centrally quantified known and novel cardiovascular biomarkers, prior to and 3 months after ablation for atrial fibrillation (AF).

Purpose

In patients enrolled in the AXAFA-AFNET5 trial, we 1) characterised changes in 12 biomarker levels pre and post-ablation, 2) ascertained if biomarker changes are consistent between males and females, and 3) identified biomarkers which predict recurrent AF post-ablation.

Methods and results

Of the 674 patients who were recruited and randomised, 633 received the study drug and underwent ablation. Peripheral blood samples were available for 488 patients at baseline and 434 at 3 months follow-up (median age [Q1, Q3] 64 [58, 70] years; 34% female). Between baseline (BL) and follow-up (FU), paired comparisons revealed that 3 biomarkers decreased, ANG2 (median [Q1, Q3] BL 2.185 [1.711, 3.115], FU 1.827 [1.457, 2.297] ng/mL, p&lt;0.001), BMP10 (BL 2.056 [1.810, 2.380], FU 1.986 [1.757, 2.260] ng/mL, p&lt;0.001), and NTproBNP (BL 2.219 [0.858, 5.731] per 100pg/mL, p&lt;0.001), while 1 biomarker increased, FABP3 (BL 2.911 [2.425, 3.508], FU 2.911 [2.462, 3.521], p=0.005). The remaining 8 biomarkers remained unchanged.

Significant differences in ANG2, BMP10, NTproBNP and FABP3 were driven by patients who remained arrhythmia free at follow-up whereas biomarker levels remained unchanged in 121 patients who experienced recurrent AF (39%; Figure). Change scores were mainly consistent between males and females, however, CRP decreased significantly more in females. Recurrent AF episodes were not different between males and females (p=0.319).

Cox proportional hazards model assessed the relationship of individual biomarkers at baseline for predicting recurrent AF. Elevated ANG2 (hazard ratio, HR per ng/mL [95% confidence interval] 1.214 [1.113, 1.325]), BMP10 (HR per ng/mL 1.516 [1.039, 2.214]), and NTproBNP (HR per 100 pg/mL 1.050 [1.025, 1.076]) significantly predicted increased risk for recurrent AF, after adjustment for age, sex, body mass index, hypertension, diabetes, chronic obstructive pulmonary disease, stroke, heart failure, ablation type (PVI, PVI and other, other), ablation energy (radiofrequency, cryoablation, other), and treatment arm.

Conclusion

In this study, most cardiovascular biomarkers are unchanged after ablation for AF, however, ANG2, BMP10, and NTproBNP decreased at follow-up. These effects are driven by patients who remained arrhythmia free and could potentially reflect improvement in vascular (ANG2), endothelial (BMP10), and myocardial load (NTproBNP) parameters post-ablation. This outcome corresponds with the observation that elevated levels of these biomarkers at baseline predict recurrent AF at 3 months. Both males and females demonstrate similar changes in biomarker profiles and benefit equally from ablation for AF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): DZHK (German Centre for Cardiovascular Research) and BMBF (German Ministry of Education and Research) to AFNET.Additional support from European Union [grant agreement No. 633196 (CATCH ME)]. Biomarker changes

Search for New Phenomena in Final States with Two Leptons and One or No b-Tagged Jets at sqrt[s]=13 TeV Using the ATLAS Detector

A search for new phenomena is presented in final states with two leptons and one or no b-tagged jets. The event selection requires the two leptons to have opposite charge, the same flavor (electrons or muons), and a large invariant mass. The analysis is based on the full run-2 proton-proton collision dataset recorded at a center-of-mass energy of sqrt[s]=13  TeV by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 139  fb^{-1}. No significant deviation from the expected background is observed in the data. Inspired by the B-meson decay anomalies, a four-fermion contact interaction between two quarks (b, s) and two leptons (ee or μμ) is used as a benchmark signal model, which is characterized by the energy scale and coupling, Λ and g_{*}, respectively. Contact interactions with Λ/g_{*} lower than 2.0 (2.4) TeV are excluded for electrons (muons) at the 95% confidence level, still far below the value that is favored by the B-meson decay anomalies. Model-independent limits are set as a function of the minimum dilepton invariant mass, which allow the results to be reinterpreted in various signal scenarios.

Search for Displaced Leptons in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector

A search for charged leptons with large impact parameters using 139  fb^{-1} of sqrt[s]=13  TeV pp collision data from the ATLAS detector at the LHC is presented, addressing a long-standing gap in coverage of possible new physics signatures. Results are consistent with the background prediction. This search provides unique sensitivity to long-lived scalar supersymmetric lepton partners (sleptons). For lifetimes of 0.1 ns, selectron, smuon, and stau masses up to 720, 680, and 340  GeV, respectively, are excluded at 95% confidence level, drastically improving on the previous best limits from LEP.

Laminar airflow versus turbulent airflow in simulated total hip arthroplasty: measurements of colony-forming units, particles, and energy consumption

BACKGROUND

The optimal type of ventilation in operating theatres for joint arthroplasty has been debated for decades. Recently, the World Health Organization changed its recommendations based on articles that have since been criticized. The economic and environmental impact of ventilation is also currently an important research topic but has not been well investigated.

AIM

To compare how large, high-volume, laminar airflow (LAF) and turbulent airflow (TAF) ventilation systems perform during standardized simulated total hip arthroplasty (THA), as they pertain to colony-forming units (cfu), particle counts, and energy consumption.

METHODS

Two identical operating theatres were used to perform simulated THA. The only difference was that one was equipped with LAF and the other with TAF. Cfu and particles were collected from key points in the operating theatre, and energy was measured for each simulation. Thirty-two simulations were done in total.

FINDINGS

LAF had significantly reduced cfu and particle count when compared with TAF, at both 100% and 50% air influx. Furthermore, it was shown that lowering the air influx by 50% in LAF did not significantly affect cfu or particles, although reducing the fresh air influx from 100% to 50% significantly lowered the energy consumption. Most simulations in TAF did not meet the cleanroom requirements.

CONCLUSION

Cfu were significantly lower in LAF at both 100% and 50% air influx. It is possible to reduce fresh air influx in LAF operating theatres by 50%, significantly reducing energy consumption, while still maintaining cfu and particle counts below the ISO classification threshold required for THA surgery.

No prognostic benefit of multimodality imaging-guided left ventricular lead placement in cardiac resynchronization therapy: Long-term follow-up of the ImagingCRT study

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Aarhus University, the Danish Heart Foundation, Health Research Foundation of Central Denmark Region, and Gangstedfonden.

Background

 

Observational data indicate that left ventricular (LV) lead placement at the latest contracting region and separate from myocardial scar is associated with improved prognosis in cardiac resynchronization therapy (CRT). In a double-blinded, randomized controlled trial (ImagingCRT), we tested the strategy of multimodality imaging-guided LV lead placement towards the latest mechanically activated non-scarred myocardial segment in CRT. Patients were included between 2011 and 2014 and allocated either to (1) imaging-guided LV lead placement using cardiac computed tomography, 99mTechnetium myocardial perfusion imaging, and speckle-tracking echocardiography (imaging group, n = 89) or to (2) routine LV lead implantation in a posterolateral region with late electrical activation (control group, n = 93). The multimodality imaging-guided strategy was found to reduce proportion of non-responders to CRT after 6 months. Impact on long-term clinical outcome is unknown.

Purpose

To evaluate the long-term effect of individualized multimodality imaging-guided LV lead placement compared to a routine fluoroscopic approach on the composite endpoint of death or heart failure (HF) hospitalization after CRT.

Method

We reviewed follow-up data until November 2020 for all 182 patients included in the ImagingCRT trial for the occurrence of HF hospitalization and all-cause death. Continuous variables are presented as median (interquartile range) or mean ± standard deviation. We used Kaplan-Meier plot and Cox proportional hazard regression analysis (unadjusted) to assess the risk of HF hospitalization and all-cause death, and used log-rank test for comparison between the two groups.

Results

All patients had standard CRT indication (left bundle branch block, New York Heart Association functional class II/ III/ IV 84 [46%]/ 92 [51%]/ 6 [3%], LV ejection fraction 25 ± 6%, QRS width 166 ± 22 milliseconds). Mean age was 70 ± 9 years, and 39 (21%) were female. During a median follow-up period of 6.7 years (3.3–7.9 years), the proportion of patients meeting the composite endpoint of HF hospitalization (n = 45 [25%]) or all-cause death (n = 56 [31%]) was 60% (n = 53) in the imaging group compared with 52% (n = 48) in the control group (hazard ratio [HR] 1.22, 95% confidence interval [CI] 0.83–1.81, p = 0.31) (Figure 1).

Neither the risk of HF hospitalization (HR 1.11, 95% CI 0.62–1.99, p = 0.72) or of all-cause death differed between the two groups (HR 1.23, 95% CI 0.82–1.85, p = 0.32).

Conclusion

An individualized multimodality imaging-guided strategy targeting LV lead placement towards the latest mechanically activated non-scarred myocardial segment during CRT implantation did not reduce the composite outcome of HF hospitalization or all-cause death during long-term follow-up. Abstract Figure 1

Effectiveness of internet-based cognitive behavioural therapy for binge eating disorder

Introduction

Binge eating disorder (BED) is the most prevalent specific eating disorder. It is characterized by recurrent episodes of binge eating and is associated with feelings of shame and a lack of control. Internet-based treatments are gaining increasing attention as a way to reach more patients with evidence based treatments In 2020 we conducted a preliminary analysis on the effectiveness of an internet-based cognitive behavioural therapy treatment project (Jensen ES, Linnet, J, Holmberg TT, Tarp K, Nielsen JH, Lichtenstein MB. Effectiveness of internet-based guided self-help for binge-eating disorder and characteristics of completers versus noncompleters. Int J Eat Disord. 2020;1-6. https://doi.org/10.1002/eat.23384).

Objectives

This study aims to update the analyses on treatment effect with the patients who have completed treatment in the year following the last data extraction.

Methods

The iBED treatment project is a 10-session psychologist guided internet-based self-help program based on cognitive behavioural therapy. When applying for treatment and upon completion patients respond to a survey containing, among other scales, the eating disorder examination-questionnaire (EDE-Q), binge eating disorder-questionnaire (BED-Q) and various sociodemographic questions. Data will be extracted from the treatment project in anonymized form for analyses.

Results

The preliminary analyses were conducted on 36 completers. These showed large standardized effect sizes on both the EDE-Q subscales (Cohens d ranging from .88-1.65) and on the BED-Q (d = 1.38). The updated effectiveness analyses will be presented at the conference. We expect approximately 70-80 patients to have completed treatment at this time.

Conclusions

Results will be discussed and presented at the conference.

Longitudinal Flow Decorrelations in Xe+Xe Collisions at sqrt[s_{NN}]=5.44 TeV with the ATLAS Detector

The first measurement of longitudinal decorrelations of harmonic flow amplitudes v_{n} for n=2-4 in Xe+Xe collisions at sqrt[s_{NN}]=5.44  TeV is obtained using 3  μb^{-1} of data with the ATLAS detector at the LHC. The decorrelation signal for v_{3} and v_{4} is found to be nearly independent of collision centrality and transverse momentum (p_{T}) requirements on final-state particles, but for v_{2} a strong centrality and p_{T} dependence is seen. When compared with the results from Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV, the longitudinal decorrelation signal in midcentral Xe+Xe collisions is found to be larger for v_{2}, but smaller for v_{3}. Current hydrodynamic models reproduce the ratios of the v_{n} measured in Xe+Xe collisions to those in Pb+Pb collisions but fail to describe the magnitudes and trends of the ratios of longitudinal flow decorrelations between Xe+Xe and Pb+Pb. The results on the system-size dependence provide new insights and an important lever arm to separate effects of the longitudinal structure of the initial state from other early and late time effects in heavy-ion collisions.

Search for Dark Matter Produced in Association with a Dark Higgs Boson Decaying into W^{±}W^{∓} or ZZ in Fully Hadronic Final States from sqrt[s]=13 TeV pp Collisions Recorded with the ATLAS Detector

Several extensions of the Standard Model predict the production of dark matter particles at the LHC. An uncharted signature of dark matter particles produced in association with VV=W^{±}W^{∓} or ZZ pairs from a decay of a dark Higgs boson s is searched for using 139  fb^{-1} of pp collisions recorded by the ATLAS detector at a center-of-mass energy of 13 TeV. The s→V(qq[over ¯])V(qq[over ¯]) decays are reconstructed with a novel technique aimed at resolving the dense topology from boosted VV pairs using jets in the calorimeter and tracking information. Dark Higgs scenarios with m_{s}>160  GeV are excluded.

Anode heel effect: Does it impact image quality in digital radiography? A systematic literature review

INTRODUCTION

The anode heel effect can be used to optimize image quality and/or patient dose in digital radiography (DR). In film-screen radiography, the effect can equalize optical density in regions of varying attenuation. Clinical experience suggests that the implementation of DR has led to less awareness of anode orientation. Post-processing is assumed to compensate, but may also alter image impression and potentially obscure image details. Published evidence was examined for the influence of the anode heel effect on image quality in DR.

METHOD

A systematic literature search was carried out using PubMed, Embase, and Web of Science databases. Title and abstracts were screened blinded by three authors, according to in-/exclusion criteria, followed by full-text analysis for final inclusion. Studies where technical and/or visual image quality were reported, was included. All studies were analyzed and assigned quality scores, according to relevant questions. The authors devised a scoring system based on reported information pertaining to reproducibility, interpretation, and generalizability of the methods and conclusions.

RESULTS

Five studies were included of heterogeneous design, each with methodological shortcomings. Only a few anatomical areas were covered. Very few patients were examined, and in no studies were images evaluated by radiologists or reporting radiographers. Relevant information such as post-processing, image quality criteria and analysis was insufficient in most studies, making reproduction difficult. Results were contradictory, especially concerning technical vs visual image quality.

CONCLUSION

Limited published evidence was found quantifying the influence of the anode heel effect on image quality using DR technology. More methodologically, robust studies are needed. The published evidence neither proves nor disproves the impact of the heel effect on image quality in DR.

IMPLICATIONS FOR PRACTICE

Based on a systematic review, no firm recommendations for anode orientation relating to image quality in DR can be provided.

A systems biology approach to understand gut microbiota and host metabolism in morbid obesity: design of the BARIA Longitudinal Cohort Study

INTRODUCTION

Prevalence of obesity and associated diseases, including type 2 diabetes mellitus, dyslipidaemia and non-alcoholic fatty liver disease (NAFLD), are increasing. Underlying mechanisms, especially in humans, are unclear. Bariatric surgery provides the unique opportunity to obtain biopsies and portal vein blood-samples.

METHODS

The BARIA Study aims to assess how microbiota and their metabolites affect transcription in key tissues and clinical outcome in obese subjects and how baseline anthropometric and metabolic characteristics determine weight loss and glucose homeostasis after bariatric surgery. We phenotype patients undergoing bariatric surgery (predominantly laparoscopic Roux-en-Y gastric bypass), before weight loss, with biometrics, dietary and psychological questionnaires, mixed meal test (MMT) and collect fecal-samples and intra-operative biopsies from liver, adipose tissues and jejunum. We aim to include 1500 patients. A subset (approximately 25%) will undergo intra-operative portal vein blood-sampling. Fecal-samples are analyzed with shotgun metagenomics and targeted metabolomics, fasted and postprandial plasma-samples are subjected to metabolomics, and RNA is extracted from the tissues for RNAseq-analyses. Data will be integrated using state-of-the-art neuronal networks and metabolic modeling. Patient follow-up will be ten years.

RESULTS

Preoperative MMT of 170 patients were analysed and clear differences were observed in glucose homeostasis between individuals. Repeated MMT in 10 patients showed satisfactory intra-individual reproducibility, with differences in plasma glucose, insulin and triglycerides within 20% of the mean difference.

CONCLUSION

The BARIA study can add more understanding in how gut-microbiota affect metabolism, especially with regard to obesity, glucose metabolism and NAFLD. Identification of key factors may provide diagnostic and therapeutic leads to control the obesity-associated disease epidemic.

Medium-Induced Modification of Z-Tagged Charged Particle Yields in Pb+Pb Collisions at 5.02 TeV with the ATLAS Detector

The yield of charged particles opposite to a Z boson with large transverse momentum (p_{T}) is measured in 260  pb^{-1} of pp and 1.7  nb^{-1} of Pb+Pb collision data at 5.02 TeV per nucleon pair recorded with the ATLAS detector at the Large Hadron Collider. The Z boson tag is used to select hard-scattered partons with specific kinematics, and to observe how their showers are modified as they propagate through the quark-gluon plasma created in Pb+Pb collisions. Compared with pp collisions, charged-particle yields in Pb+Pb collisions show significant modifications as a function of charged-particle p_{T} in a way that depends on event centrality and Z boson p_{T}. The data are compared with a variety of theoretical calculations and provide new information about the medium-induced energy loss of partons in a p_{T} regime difficult to measure through other channels.

Observation and Measurement of Forward Proton Scattering in Association with Lepton Pairs Produced via the Photon Fusion Mechanism at ATLAS

The observation of forward proton scattering in association with lepton pairs (e^{+}e^{-}+p or μ^{+}μ^{-}+p) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer, while the leptons are reconstructed by the central ATLAS detector. Proton-proton collision data recorded in 2017 at a center-of-mass energy of sqrt[s]=13  TeV are analyzed, corresponding to an integrated luminosity of 14.6  fb^{-1}. A total of 57 (123) candidates in the ee+p (μμ+p) final state are selected, allowing the background-only hypothesis to be rejected with a significance exceeding 5 standard deviations in each channel. Proton-tagging techniques are introduced for cross-section measurements in the fiducial detector acceptance, corresponding to σ_{ee+p}=11.0±2.6(stat)±1.2(syst)±0.3(lumi) and σ_{μμ+p}=7.2±1.6(stat)±0.9(syst)±0.2(lumi)  fb in the dielectron and dimuon channel, respectively.

Search for Heavy Resonances Decaying into a Photon and a Hadronically Decaying Higgs Boson in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter presents a search for the production of new heavy resonances decaying into a Higgs boson and a photon using proton-proton collision data at sqrt[s]=13  TeV collected by the ATLAS detector at the LHC. The data correspond to an integrated luminosity of 139  fb^{-1}. The analysis is performed by reconstructing hadronically decaying Higgs boson (H→bb[over ¯]) candidates as single large-radius jets. A novel algorithm using information about the jet constituents in the center-of-mass frame of the jet is implemented to identify the two b quarks in the single jet. No significant excess of events is observed above the expected background. Upper limits are set on the production cross-section times branching fraction for narrow spin-1 resonances decaying into a Higgs boson and a photon in the resonance mass range from 0.7 to 4 TeV, cross-section times branching fractions are excluded between 11.6 fb and 0.11 fb at a 95% confidence level.

Search for Higgs Boson Decays into a Z Boson and a Light Hadronically Decaying Resonance Using 13 TeV pp Collision Data from the ATLAS Detector

A search for Higgs boson decays into a Z boson and a light resonance in two-lepton plus jet events is performed, using a pp collision dataset with an integrated luminosity of 139  fb^{-1} collected at sqrt[s]=13  TeV by the ATLAS experiment at the CERN LHC. The resonance considered is a light boson with a mass below 4 GeV from a possible extended scalar sector or a charmonium state. Multivariate discriminants are used for the event selection and for evaluating the mass of the light resonance. No excess of events above the expected background is found. Observed (expected) 95% confidence-level upper limits are set on the Higgs boson production cross section times branching fraction to a Z boson and the signal resonance, with values in the range 17-340 pb (16_{-5}^{+6}-320_{-90}^{+130}  pb) for the different light spin-0 boson mass and branching fraction hypotheses, and with values of 110 and 100 pb (100_{-30}^{+40} and 100_{-30}^{+40}  pb) for the η_{c} and J/ψ hypotheses, respectively.

Dijet Resonance Search with Weak Supervision Using sqrt[s]=13 TeV pp Collisions in the ATLAS Detector

This Letter describes a search for narrowly resonant new physics using a machine-learning anomaly detection procedure that does not rely on signal simulations for developing the analysis selection. Weakly supervised learning is used to train classifiers directly on data to enhance potential signals. The targeted topology is dijet events and the features used for machine learning are the masses of the two jets. The resulting analysis is essentially a three-dimensional search A→BC, for m_{A}∼O(TeV), m_{B},m_{C}∼O(100  GeV) and B, C are reconstructed as large-radius jets, without paying a penalty associated with a large trials factor in the scan of the masses of the two jets. The full run 2 sqrt[s]=13  TeV pp collision dataset of 139  fb^{-1} recorded by the ATLAS detector at the Large Hadron Collider is used for the search. There is no significant evidence of a localized excess in the dijet invariant mass spectrum between 1.8 and 8.2 TeV. Cross-section limits for narrow-width A, B, and C particles vary with m_{A}, m_{B}, and m_{C}. For example, when m_{A}=3  TeV and m_{B}≳200  GeV, a production cross section between 1 and 5 fb is excluded at 95% confidence level, depending on m_{C}. For certain masses, these limits are up to 10 times more sensitive than those obtained by the inclusive dijet search. These results are complementary to the dedicated searches for the case that B and C are standard model bosons.

CP Properties of Higgs Boson Interactions with Top Quarks in the tt[over ¯]H and tH Processes Using H→γγ with the ATLAS Detector

A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production in association with a top quark pair (tt[over ¯]H) or single top quark (tH) is studied. The analysis uses 139  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of sqrt[s]=13  TeV with the ATLAS detector at the Large Hadron Collider. Assuming a CP-even coupling, the tt[over ¯]H process is observed with a significance of 5.2 standard deviations. The measured cross section times H→γγ branching ratio is 1.64_{-0.36}^{+0.38}(stat)_{-0.14}^{+0.17}(sys)  fb, and the measured rate for tt[over ¯]H is 1.43_{-0.31}^{+0.33}(stat)_{-0.15}^{+0.21}(sys) times the Standard Model expectation. The tH production process is not observed and an upper limit on its rate of 12 times the Standard Model expectation is set. A CP-mixing angle greater (less) than 43 (-43)° is excluded at 95% confidence level.

Antipsychotic medication exposure, clozapine, and pneumonia: results from a self-controlled study

OBJECTIVE

By using a self-controlled design, we investigated whether antipsychotic medication exposure was associated with increased pneumonia risk and whether patients receiving clozapine were more likely to develop pneumonia than patients receiving other antipsychotic medications.

METHODS

Through nationwide health registers, we identified all out-patients with schizophrenia initiating antipsychotic treatment. First, we estimated whether antipsychotic-naïve patients with schizophrenia increased their risk of pneumonia after initiation of either a first- or second-generation antipsychotic medication using a one-year mirror-image model. Afterward, similar analyses were made for individual second-generation antipsychotics. Lastly, the rate of pneumonia for patients initiated on clozapine was compared to patients commenced on other second-generation antipsychotics.

RESULTS

In total, 8355 antipsychotic-naïve patients with schizophrenia were initiated on a first-generation antipsychotic medication; 0.95% of the patients had developed pneumonia before exposure, compared to 0.68% after exposure (P = 0.057). Similar findings were made for the 8001 antipsychotic-naïve patients with schizophrenia initiated on second-generation antipsychotic medications, with 0.56% developing pneumonia before exposure compared to 0.55% after exposure (P = 1.00). Second-generation antipsychotic medications did not increase the pneumonia risk, except for risperidone (increased by 0.32%; P = 0.007) and clozapine, which gave the largest absolute increase in pneumonia risk although not significant (increased by 0.64%; P = 0.10). The rate of pneumonia was higher after initiation of clozapine than for other second-generation antipsychotic medications.

CONCLUSION

Most antipsychotic medications were not found to increase the risk of pneumonia. Clozapine exposure might be associated with increased risk of developing pneumonia.

Search for Heavy Higgs Bosons Decaying into Two Tau Leptons with the ATLAS Detector Using pp Collisions at sqrt[s]=13 TeV

A search for heavy neutral Higgs bosons is performed using the LHC Run 2 data, corresponding to an integrated luminosity of 139  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV recorded with the ATLAS detector. The search for heavy resonances is performed over the mass range 0.2-2.5 TeV for the τ^{+}τ^{-} decay with at least one τ-lepton decaying into final states with hadrons. The data are in good agreement with the background prediction of the standard model. In the M_{h}^{125} scenario of the minimal supersymmetric standard model, values of tanβ>8 and tanβ>21 are excluded at the 95% confidence level for neutral Higgs boson masses of 1.0 and 1.5 TeV, respectively, where tanβ is the ratio of the vacuum expectation values of the two Higgs doublets.