Improved accuracy and robustness of electron density profiles from JET's X-mode frequency-modulated continuous-wave reflectometers

JET's frequency-modulated continuous wave (FMCW) reflectometers have been operating well with the current design since 2005, and density profiles have been automatically calculated intershot since then. However, the calculated profiles had long suffered from several shortcomings: poor agreement with other diagnostics, sometimes inappropriately moving radially by several centimeters, elevated levels of radial jitter, and persistent wriggles (strong unphysical oscillations). In this research, several techniques are applied to the reflectometry data analysis, and the shortcomings are significantly improved. Starting with improving the equilibrium reconstruction that estimates the background magnetic field, adding a ripple correction in the reconstructed magnetic field profile, and adding new inner-wall reflection positions estimated through ray-tracing, these changes not only improve the agreement of reconstructed profiles to other diagnostics but also solve density profile wriggles that were present during band transitions. Other smaller but also persistent wriggles were also suppressed by applying a localized correction to the measured beat frequency where persistent oscillations are present. Finally, the burst analysis method, as introduced by Varela et al. [Nucl. Fusion 46 S693 (2006)], has been implemented to extract the beat frequency from stacked spectrograms. Due to the strong suppression of spurious reflections, the radial jitter that sometimes would span several centimeters has been strongly reduced. The stacking of spectrograms has also been shown to be very useful for stacking recurring events, like small gas puff modulations, and extracting transport coefficients that would otherwise be below the noise level.

Amplitude Analysis of the B^{0}→K^{*0}μ^{+}μ^{-} Decay

An amplitude analysis of the B^{0}→K^{*0}μ^{+}μ^{-} decay is presented using a dataset corresponding to an integrated luminosity of 4.7  fb^{-1} of pp collision data collected with the LHCb experiment. For the first time, the coefficients associated to short-distance physics effects, sensitive to processes beyond the standard model, are extracted directly from the data through a q^{2}-unbinned amplitude analysis, where q^{2} is the μ^{+}μ^{-} invariant mass squared. Long-distance contributions, which originate from nonfactorizable QCD processes, are systematically investigated, and the most accurate assessment to date of their impact on the physical observables is obtained. The pattern of measured corrections to the short-distance couplings is found to be consistent with previous analyses of b- to s-quark transitions, with the largest discrepancy from the standard model predictions found to be at the level of 1.8 standard deviations. The global significance of the observed differences in the decay is 1.4 standard deviations.

Fraction of χ_{c} Decays in Prompt J/ψ Production Measured in pPb Collisions at sqrt[s_{NN}]=8.16 TeV

The fraction of χ_{c1} and χ_{c2} decays in the prompt J/ψ yield, F_{χ_{c}→J/ψ}=σ_{χ_{c}→J/ψ}/σ_{J/ψ}, is measured by the LHCb detector in pPb collisions at sqrt[s_{NN}]=8.16  TeV. The study covers the forward (1.5 Collapse

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Observation of Cabibbo-Suppressed Two-Body Hadronic Decays and Precision Mass Measurement of the Ω_{c}^{0} Baryon

The first observation of the singly Cabibbo-suppressed Ω_{c}^{0}→Ω^{-}K^{+} and Ω_{c}^{0}→Ξ^{-}π^{+} decays is reported, using proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4  fb^{-1}, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to be B(Ω_{c}^{0}→Ω^{-}K^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[6.08±0.51(stat)±0.40(syst)]%,B(Ω_{c}^{0}→Ξ^{-}π^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[15.81±0.87(stat)±0.44(syst)±0.16(ext)]%. In addition, using the Ω_{c}^{0}→Ω^{-}π^{+} decay channel, the Ω_{c}^{0} baryon mass is measured to be M(Ω_{c}^{0})=2695.28±0.07(stat)±0.27(syst)±0.30(ext)  MeV, improving the precision of the previous world average by a factor of 4.

Enhanced Production of Λ_{b}^{0} Baryons in High-Multiplicity pp Collisions at sqrt[s]=13 TeV

The production rate of Λ_{b}^{0} baryons relative to B^{0} mesons in pp collisions at a center-of-mass energy sqrt[s]=13  TeV is measured by the LHCb experiment. The ratio of Λ_{b}^{0} to B^{0} production cross sections shows a significant dependence on both the transverse momentum and the measured charged-particle multiplicity. At low multiplicity, the ratio measured at LHCb is consistent with the value measured in e^{+}e^{-} collisions, and increases by a factor of ∼2 with increasing multiplicity. At relatively low transverse momentum, the ratio of Λ_{b}^{0} to B^{0} cross sections is higher than what is measured in e^{+}e^{-} collisions, but converges with the e^{+}e^{-} ratio as the momentum increases. These results imply that the evolution of heavy b quarks into final-state hadrons is influenced by the density of the hadronic environment produced in the collision. Comparisons with several models and implications for the mechanisms enforcing quark confinement are discussed.

Improved Measurement of CP Violation Parameters in B_{s}^{0}→J/ψK^{+}K^{-} Decays in the Vicinity of the ϕ(1020) Resonance

The decay-time-dependent CP asymmetry in B_{s}^{0}→J/ψ(→μ^{+}μ^{-})K^{+}K^{-} decays is measured using proton-proton collision data, corresponding to an integrated luminosity of 6  fb^{-1}, collected with the LHCb detector at a center-of-mass energy of 13 TeV. Using a sample of approximately 349 000 B_{s}^{0} signal decays with an invariant K^{+}K^{-} mass in the vicinity of the ϕ(1020) resonance, the CP-violating phase ϕ_{s} is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the B_{s}^{0}-B[over ¯]_{s}^{0} system, ΔΓ_{s}, and the difference of the average B_{s}^{0} and B^{0} meson decay widths, Γ_{s}-Γ_{d}. The values obtained are ϕ_{s}=-0.039±0.022±0.006  rad, ΔΓ_{s}=0.0845±0.0044±0.0024  ps^{-1}, and Γ_{s}-Γ_{d}=-0.0056_{-0.0015}^{+0.0013}±0.0014  ps^{-1}, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements to date and are consistent with expectations based on the Standard Model and with the previous LHCb analyses of this decay. These results are combined with previous independent LHCb measurements. The phase ϕ_{s} is also measured independently for each polarization state of the K^{+}K^{-} system and shows no evidence for polarization dependence.

Measurement of CP Violation in B^{0}→ψ(→ℓ^{+}ℓ^{-})K_{S}^{0}(→π^{+}π^{-}) Decays

A measurement of time-dependent CP violation in the decays of B^{0} and B[over ¯]^{0} mesons to the final states J/ψ(→μ^{+}μ^{-})K_{S}^{0}, ψ(2S)(→μ^{+}μ^{-})K_{S}^{0} and J/ψ(→e^{+}e^{-})K_{S}^{0} with K_{S}^{0}→π^{+}π^{-} is presented. The data correspond to an integrated luminosity of 6  fb^{-1} collected at a center-of-mass energy of sqrt[s]=13  TeV with the LHCb detector. The CP-violation parameters are measured to be S_{ψK_{S}^{0}}=0.717±0.013(stat)±0.008(syst) and C_{ψK_{S}^{0}}=0.008±0.012(stat)±0.003(syst). This measurement of S_{ψK_{S}^{0}} represents the most precise single measurement of the CKM angle β to date and is more precise than the current world average. In addition, measurements of the CP-violation parameters of the individual channels are reported and a combination with the LHCb Run 1 measurements is performed.

Observation of New Baryons in the Ξ_{b}^{-}π^{+}π^{-} and Ξ_{b}^{0}π^{+}π^{-} Systems

The first observation and study of two new baryonic structures in the final state Ξ_{b}^{0}π^{+}π^{-} and the confirmation of the Ξ_{b}(6100)^{-} state in the Ξ_{b}^{-}π^{+}π^{-} decay mode are reported using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. In addition, the properties of the known Ξ_{b}^{*0}, Ξ_{b}^{'-} and Ξ_{b}^{*-} resonances are measured with improved precision. The new decay mode of the Ξ_{b}^{0} baryon to the Ξ_{c}^{+} π^{-} π^{+} π^{-} final state is observed and exploited for the first time in these measurements.

Precision Measurement of CP Violation in the Penguin-Mediated Decay B_{s}^{0}→ϕϕ

A flavor-tagged time-dependent angular analysis of the decay B_{s}^{0}→ϕϕ is performed using pp collision data collected by the LHCb experiment at the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6  fb^{-1}. The CP-violating phase and direct CP-violation parameter are measured to be ϕ_{s}^{ss[over ¯]s}=-0.042±0.075±0.009  rad and |λ|=1.004±0.030±0.009, respectively, assuming the same values for all polarization states of the ϕϕ system. In these results, the first uncertainties are statistical and the second systematic. These parameters are also determined separately for each polarization state, showing no evidence for polarization dependence. The results are combined with previous LHCb measurements using pp collisions at center-of-mass energies of 7 and 8 TeV, yielding ϕ_{s}^{ss[over ¯]s}=-0.074±0.069  rad and |λ|=1.009±0.030. This is the most precise study of time-dependent CP violation in a penguin-dominated B meson decay. The results are consistent with CP symmetry and with the standard model predictions.

Measurement of the Λ_{b}^{0}→Λ(1520)μ^{+}μ^{-} Differential Branching Fraction

The branching fraction of the rare decay Λ_{b}^{0}→Λ(1520)μ^{+}μ^{-} is measured for the first time, in the squared dimuon mass intervals q^{2}, excluding the J/ψ and ψ(2S) regions. The data sample analyzed was collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9  fb^{-1}. The result in the highest q^{2} interval, q^{2}>15.0  GeV^{2}/c^{4}, where theoretical predictions have the smallest model dependence, agrees with the predictions.

Observation of New Ω_{c}^{0} States Decaying to the Ξ_{c}^{+}K^{-} Final State

Two new excited states, Ω_{c}(3185)^{0} and Ω_{c}(3327)^{0}, are observed in the Ξ_{c}^{+}K^{-} invariant-mass spectrum using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. Five previously observed excited Ω_{c}^{0} states are confirmed, namely Ω_{c}(3000)^{0}, Ω_{c}(3050)^{0}, Ω_{c}(3065)^{0}, Ω_{c}(3090)^{0}, and Ω_{c}(3119)^{0}. The masses and widths of these seven states are measured with the highest precision to date.

Evidence of a J/ψK_{S}^{0} Structure in B^{0}→J/ψϕK_{S}^{0} Decays

An amplitude analysis of B^{0}→J/ψϕK_{S}^{0} decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 9  fb^{-1}, collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. Evidence with a significance of 4.0 standard deviations of a structure in the J/ψK_{S}^{0} system, named T_{ψs1}^{θ}(4000)^{0}, is seen, with its mass and width measured to be 3991_{-10}^{+12} _{-17}^{+9}  MeV/c^{2} and 105_{-25}^{+29} _{-23}^{+17}  MeV, respectively, where the first uncertainty is statistical and the second systematic. The T_{ψs1}^{θ}(4000)^{0} state is likely to be the isospin partner of the T_{ψs1}^{θ}(4000)^{+} state, previously observed in the J/ψK^{+} system of the B^{+}→J/ψϕK^{+} decay. When isospin symmetry for the charged and neutral T_{ψs1}^{θ}(4000) states is assumed, the signal significance increases to 5.4 standard deviations.

Measurement of the Ratios of Branching Fractions R(D^{*}) and R(D^{0})

The ratios of branching fractions R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}μ^{-}ν[over ¯]_{μ}) and R(D^{0})≡B(B^{-}→D^{0}τ^{-}ν[over ¯]_{τ})/B(B^{-}→D^{0}μ^{-}ν[over ¯]_{μ}) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ^{-}→μ^{-}ν_{τ}ν[over ¯]_{μ}. The measured values are R(D^{*})=0.281±0.018±0.024 and R(D^{0})=0.441±0.060±0.066, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is ρ=-0.43. The results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the standard model.

Measurement of the Prompt D^{0} Nuclear Modification Factor in p-Pb Collisions at sqrt[s_{NN}]=8.16 TeV

The production of prompt D^{0} mesons in proton-lead collisions in both the forward and backward rapidity regions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=8.16  TeV is measured by the LHCb experiment. The nuclear modification factor of prompt D^{0} mesons is determined as a function of the transverse momentum p_{T}, and the rapidity in the nucleon-nucleon center-of-mass frame y^{*}. In the forward rapidity region, significantly suppressed production with respect to pp collisions is measured, which provides significant constraints on models of nuclear parton distributions and hadron production down to the very low Bjorken-x region of ∼10^{-5}. In the backward rapidity region, a suppression with a significance of 2.0-3.8 standard deviations compared to parton distribution functions in a nuclear environment expectations is found in the kinematic region of p_{T}>6  GeV/c and -3.25 Collapse

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Measurement of the Time-Integrated CP Asymmetry in D^{0}→K^{-}K^{+} Decays

The time-integrated CP asymmetry in the Cabibbo-suppressed decay D^{0}→K^{-}K^{+} is measured using proton-proton collision data, corresponding to an integrated luminosity of 5.7  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. The D^{0} mesons are required to originate from promptly produced D^{*+}→D^{0}π^{+} decays, and the charge of the companion pion is used to determine the flavor of the charm meson at production. The time-integrated CP asymmetry is measured to be A_{CP}(K^{-}K^{+})=[6.8±5.4±1.6]×10^{-4} where the first uncertainty is statistical and the second systematic. The direct CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, a_{K^{-}K^{+}}^{d} and a_{π^{-}π^{+}}^{d}, are derived by combining A_{CP}(K^{-}K^{+}) with the time-integrated CP asymmetry difference, ΔA_{CP}=A_{CP}(K^{-}K^{+})-A_{CP}(π^{-}π^{+}), and other inputs, giving a_{K^{-}K^{+}}^{d}=(7.7±5.7)×10^{-4},a_{π^{-}π^{+}}^{d}=(23.2±6.1)×10^{-4},with a correlation coefficient corresponding to ρ=0.88. The compatibility of these results with CP symmetry is 1.4 and 3.8 standard deviations for D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, respectively. This is the first evidence for direct CP violation in a specific D^{0} decay.

Measurement of the Branching Fractions B(B^{0}→pp[over ¯]pp[over ¯]) and B(B_{s}^{0}→pp[over ¯]pp[over ¯])

Searches for the rare hadronic decays B^{0}→pp[over ¯]pp[over ¯] and B_{s}^{0}→pp[over ¯]pp[over ¯] are performed using proton-proton collision data recorded by the LHCb experiment and corresponding to an integrated luminosity of 9  fb^{-1}. Significances of 9.3σ and 4.0σ, including statistical and systematic uncertainties, are obtained for the B^{0}→pp[over ¯]pp[over ¯] and B_{s}^{0}→pp[over ¯]pp[over ¯] signals, respectively. The branching fractions are measured relative to the topologically similar normalization decays B^{0}→J/ψ(→pp[over ¯])K^{*0}(→K^{+}π^{-}) and B_{s}^{0}→J/ψ(→pp[over ¯])⁢ϕ(→K^{+}K^{-}). The branching fractions are measured to be B(B^{0}→pp[over ¯]pp[over ¯])=(2.2±0.4±0.1±0.1)×10^{-8} and B(B_{s}^{0}→pp[over ¯]pp[over ¯])=(2.3±1.0±0.2±0.1)×10^{-8}. In these measurements, the first uncertainty is statistical, the second is systematic, and the third one is due to the external branching fraction of the normalization channel.

Observation of a Resonant Structure near the D_{s}^{+}D_{s}^{-} Threshold in the B^{+}→D_{s}^{+}D_{s}^{-}K^{+} Decay

An amplitude analysis of the B^{+}→D_{s}^{+}D_{s}^{-}K^{+} decay is carried out to study for the first time its intermediate resonant contributions, using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. A near-threshold peaking structure, referred to as X(3960), is observed in the D_{s}^{+}D_{s}^{-} invariant-mass spectrum with significance greater than 12 standard deviations. The mass, width, and the quantum numbers of the structure are measured to be 3956±5±10  MeV, 43±13±8  MeV, and J^{PC}=0^{++}, respectively, where the first uncertainties are statistical and the second systematic. The properties of the new structure are consistent with recent theoretical predictions for a state composed of cc[over ¯]ss[over ¯] quarks. Evidence for an additional structure is found around 4140 MeV in the D_{s}^{+}D_{s}^{-} invariant mass, which might be caused either by a new resonance with the 0^{++} assignment or by a J/ψϕ↔D_{s}^{+}D_{s}^{-} coupled-channel effect.

Evidence for Modification of b Quark Hadronization in High-Multiplicity pp Collisions at sqrt[s]=13 TeV

The production rate of B_{s}^{0} mesons relative to B^{0} mesons is measured by the LHCb experiment in pp collisions at a center-of-mass energy sqrt[s]=13  TeV over the forward rapidity interval 2 Collapse

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Test of Lepton Universality in b→sℓ^{+}ℓ^{-} Decays

The first simultaneous test of muon-electron universality using B^{+}→K^{+}ℓ^{+}ℓ^{-} and B^{0}→K^{*0}ℓ^{+}ℓ^{-} decays is performed, in two ranges of the dilepton invariant-mass squared, q^{2}. The analysis uses beauty mesons produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9  fb^{-1}. Each of the four lepton universality measurements reported is either the first in the given q^{2} interval or supersedes previous LHCb measurements. The results are compatible with the predictions of the Standard Model.

Predicting Dental Caries in Young Children in Primary Health Care Settings

Young children need increased access to dental prevention and care. Targeting high caries risk children first helps meet this need. The objective of this study was to develop a parent-completed, easy-to-score, short, accurate caries risk tool for screening in primary health care settings to identify children at increased risk for cavities. A longitudinal, prospective, multisite, cohort study enrolled (primarily through primary health care settings) and followed 985 (out of 1,326) 1-y-old children and their primary caregivers (PCGs) until age 4. The PCG completed a 52-item self-administered questionnaire, and children were examined using the International Caries Detection and Assessment Criteria (ICDAS) at 12 ± 3 mo (baseline), 30 ± 3 mo (80% retention), and 48 ± 3 mo of age (74% retention). Cavitated caries lesion (dmfs = decayed, missing, and filled surfaces; d = ICDAS ≥3) experience at 4 y of age was assessed and tested for associations with questionnaire items using generalized estimating equation models applied to logistic regression. Multivariable analysis used backward model selection, with a limit of 10 items. At age 4, 24% of children had cavitated-level caries experience; 49% were female; 14% were Hispanic, 41% were White, 33% were Black, 2% were other, and 10% were multiracial; 58% enrolled in Medicaid; and 95% lived in urban communities. The age 4 multivariable prediction model, using age 1 responses (area under the receiver operating characteristic curve = 0.73), included the following significant (P < 0.001) variables (odds ratios): child participating in public assistance programs such as Medicaid (1.74), being non-White (1.80-1.96), born premature (1.48), not born by caesarean section (1.28), snacking on sugary snacks (3 or more/d, 2.22; 1-2/d or weekly, 1.55), PCG cleaning the pacifier with juice/soda/honey or sweet drink (2.17), PCG daily sharing/tasting food with child using same spoon/fork/glass (1.32), PCG brushing their teeth less than daily (2.72), PCG's gums bleeding daily when brushing or PCG having no teeth (1.83-2.00), and PCG having cavities/fillings/extractions in past 2 y (1.55). A 10-item caries risk tool at age 1 shows good agreement with cavitated-level caries experience by age 4.

First Observation of a Doubly Charged Tetraquark and Its Neutral Partner

A combined amplitude analysis is performed for the decays B^{0}→D[over ¯]^{0}D_{s}^{+}π^{-} and B^{+}→D^{-}D_{s}^{+}π^{+}, which are related by isospin symmetry. The analysis is based on data collected by the LHCb detector in proton-proton collisions at center-of-mass energies of 7, 8, and 13 TeV. The full data sample corresponds to an integrated luminosity of 9  fb^{-1}. Two new resonant states with masses of 2.908±0.011±0.020  GeV and widths of 0.136±0.023±0.013  GeV are observed, which decay to D_{s}^{+}π^{+} and D_{s}^{+}π^{-} respectively. The former state indicates the first observation of a doubly charged open-charm tetraquark state with minimal quark content [cs[over ¯]ud[over ¯]], and the latter state is a neutral tetraquark composed of [cs[over ¯]u[over ¯]d] quarks. Both states are found to have spin-parity of 0^{+}, and their resonant parameters are consistent with each other, which suggests that they belong to an isospin triplet.

Search for Rare Decays of D^{0} Mesons into Two Muons

A search for the very rare D^{0}→μ^{+}μ^{-} decay is performed using data collected by the LHCb experiment in proton-proton collisions at sqrt[s]=7, 8, and 13 TeV, corresponding to an integrated luminosity of 9  fb^{-1}. The search is optimized for D^{0} mesons from D^{*+}→D^{0}π^{+} decays but is also sensitive to D^{0} mesons from other sources. No evidence for an excess of events over the expected background is observed. An upper limit on the branching fraction of this decay is set at B(D^{0}→μ^{+}μ^{-})<3.1×10^{-9} at a 90% C.L. This represents the world's most stringent limit, constraining models of physics beyond the standard model.

Nuclear Modification Factor of Neutral Pions in the Forward and Backward Regions in p-Pb Collisions

The nuclear modification factor of neutral pions is measured in proton-lead collisions collected at a center-of-mass energy per nucleon of 8.16 TeV with the LHCb detector. The π^{0} production cross section is measured differentially in transverse momentum (p_{T}) for 1.5 Collapse

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Observation of a J/ψΛ Resonance Consistent with a Strange Pentaquark Candidate in B^{-}→J/ψΛp[over ¯] Decays

An amplitude analysis of B^{-}→J/ψΛp[over ¯] decays is performed using 4400 signal candidates selected on a data sample of pp collisions recorded at center-of-mass energies of 7, 8, and 13 TeV with the LHCb detector, corresponding to an integrated luminosity of 9  fb^{-1}. A narrow resonance in the J/ψΛ system, consistent with a pentaquark candidate with strangeness, is observed with high significance. The mass and the width of this new state are measured to be 4338.2±0.7±0.4  MeV and 7.0±1.2±1.3  MeV, where the first uncertainty is statistical and the second systematic. The spin is determined to be 1/2 and negative parity is preferred. Because of the small Q-value of the reaction, the most precise single measurement of the B^{-} mass to date, 5279.44±0.05±0.07  MeV, is obtained.

Microbial Indicators of Dental Health, Dysbiosis, and Early Childhood Caries

Dental caries lesions are a clinical manifestation of disease, preceded by microbial dysbiosis, which is poorly characterized and thought to be associated with saccharolytic taxa. Here, we assessed the associations between the oral microbiome of children and various caries risk factors such as demographics and behavioral and clinical data across early childhood and characterized over time the salivary and dental plaque microbiome of children before clinical diagnosis of caries lesions. Children (N = 266) were examined clinically at ~1, 2.5, 4, and 6.5 y of age. The microbiome samples were collected at 1, 2.5, and 4 y. Caries groups consisted of children who remained caries free (International Caries Detection and Assessment System [ICDAS] = 0) at all time points (CFAT) (n = 50); children diagnosed with caries (ICDAS ≥ 1) at 6.5 y (C6.5), 4 y (C4), or 2.5 y of age (C2.5); and children with early caries or advanced caries lesions at specific time points. Microbial community analyses were performed on zero-radius operational taxonomic units (zOTUs) obtained from V4 of 16S ribosomal RNA gene amplicon sequences. The oral microbiome of the children was affected by various factors, including antibiotic use, demographics, and dietary habits of the children and their caregivers. At all time points, various risk factors explained more of the variation in the dental plaque microbiome than in saliva. At 1 y, composition of saliva of the C4 group differed from that of the CFAT group, while at 2.5 y, this difference was observed only in plaque. At 4 y, multiple salivary and plaque zOTUs of genera Prevotella and Leptotrichia were significantly higher in samples of the C6.5 group than those of the CFAT group. In conclusion, up to 3 y prior to clinical caries detection, the oral microbial communities were already in a state of dysbiosis that was dominated by proteolytic taxa. Plaque discriminated dysbiotic oral ecosystems from healthy ones better than saliva.

A model of non-Maxwellian electron distribution function for the analysis of ECE data in JET discharges

Recent experiments performed in JET at high level of plasma heating, in preparation of, and during the DT campaign have shown significant discrepancies between electron temperature measurements by Thomson Scattering (TS) and Electron Cyclotron Emission (ECE). In order to perform a systematic analysis of this phenomenon, a simple model of bipolar distortion of the electron distribution function has been developed, allowing analytic calculation of the EC emission and absorption coefficients. Extensive comparisons of the modelled ECE spectra (at both the 2nd and the 3rd harmonic extraordinary mode) with experimental measurements display good agreement when bulk electron distribution distortions around 1-2 times the electron thermal velocity are used and prove useful for a first level of analysis of this effect.

Investigation of Te measurements discrepancies between ECE and Thomson diagnostics in high-performance plasmas in JET

For high-temperature JET and TFTR discharges, electron cyclotron emission (ECE) measurements of central electron temperature were systematically found to be up to 20% higher than those taken with Thomson scattering. In recent high-performance JET discharges, central Te measurements, performed with LIDAR Thomson scattering and the X-mode ECE interferometer, have been studied in a large database, including deuterium (DD), and deuterium-tritium plasmas (DT). Discrepancies between Te measurements have been observed outside of the experimental uncertainties. ECE measurements, at high Te, have been found to be higher or lower than those of LIDAR, depending on the specific plasma scenario. In addition, discrepancies between the peaks of the second and third harmonic ranges of the ECE spectrum have been interpreted as evidence for the presence of non-Maxwellian features in the electron distribution function. These comparisons seem to suggest that such features can be found in most of the high-performance scenarios selected in this JET database.

Prognostic implications of biventricular uptake of bone tracers at planar scintigraphy in transthyretin cardiac amyloidosis

Background

The prognostic role of bone tracer uptake in transthyretin cardiac amyloidosis (ATTR-CA) is controversial. A further characterization of cardiac retention measured by Perugini scale with differentiation between biventricular (BiV) and isolated left ventricle (LV) uptake has never been attempted previously.

Purpose

The study investigated the potential prognostic significance of BiV uptake in ATTR-CA.

Methods

In this multicentre, observational study, we analysed data of ATTR-CA patients who underwent bone tracer scintigraphy with acquisition of both planar and single photon emission computed tomography (SPECT) imaging. Cardiac uptake was defined according to the Perugini visual scale. Planar BiV uptake was defined according to right ventricle (RV) uptake: 0= absent, 1= &lt; bone, 2= equal to bone, and 3= &gt; bone and confirmed by SPECT imaging. The primary outcome was a composite of cardiac death or hospitalization for heart failure. The secondary outcome was all-cause mortality.

Results

All 124 ATTR-CA patients enrolled had LV and RV free wall uptake on SPECT images. Of them, 93 (75%) had BiV uptake visible on planar scintigraphy. BiV uptake was found in 14%, 70%, and 92% of Perugini grade 1, 2 and 3 respectively. Compared to those with isolated LV uptake, patients with BiV uptake were older (81 vs 77 years, p=0.006) and more frequently in NYHA≥3 (32% vs 10%, p=0.018). During a median follow-up of 21 months, BiV uptake was associated with a greater occurrence of the primary outcome compared to isolated LV uptake (40% vs 19%, p=0.021), whereas the Perugini scale was not (p=0.2) (Figure 1). At multivariable analysis, NYHA class ≥3 (hazard ratio [HR] 8.1, p=0.007), eGFR &lt;60 ml/min (HR 2.1, p=0.025) and higher degree of RV uptake (HR 1.69, p=0.007) emerged as independent prognostic parameters. In an external cohort of 463 ATTR-CA patients with a median follow-up of 30 months, planar BiV uptake was independently associated with all-cause mortality, with an incremental risk in higher grades of RV uptake (p&lt;0.001) (Figure 1).

Conclusions

The presence of BiV uptake at planar scintigraphy identified ATTR-CA patients with worse cardiovascular and global outcomes (Figure 2), potentially serving as a novel prognostic marker.

Funding Acknowledgement

Type of funding sources: None.

Size matters - redefining sex differences among patients with transthyretin amyloid cardiomyopathy – have we been wrong all along?

Background

Transthyretin amyloid cardiomyopathy (ATTR-CM) is most often diagnosed in men (1–5). The few available studies suggest affected women have a more favourable cardiac phenotype (5–8), but remain unclear regarding differences in outcomes.

Objectives and methods

To characterise sex differences among consecutive patients with non-hereditary and two prevalent forms of hereditary ATTR-CM diagnosed over a 20-year period at our specialist centre through analysis of deep phenotyping at presentation, changes on serial echocardiography and overall prognosis.

Results

In total, 1732 patients were studied, comprising: 1095 with wild-type (wt)ATTR-CM; 206 with T60A-hATTR-CM; and 431 with V122I-hATTR-CM. Female prevalence was greater in T60A-hATTR-CM (29.6%) and V122I-hATTR-CM (27.8%) compared to wtATTR-CM (6%). At presentation, females were 3.3 years older than males (81.9 vs 77.8 years for wtATTR-CM; 68.7 vs 65.1 years for T60A-hATTR-CM; 77.1 vs 74.9 years for V122I-hATTR-CM). At diagnosis, non-indexed measures of wall thickness were significantly greater in males (interventricular septum in diastole (IVSd) of 17.13mm in males & 16.15mm in females; p&lt;0.001). When indexed for body surface area (BSA), we observed that the mean indexed IVSd was fairly constant in males throughout the study period, but in females, had a tendency to decrease over the same study period. Furthermore, BSA significantly influenced measures of disease severity. When indexed for BSA, overall structural and functional phenotype was similar between sexes; the few observed significant differences including indexed IVSd (9.62mm/m2 in females & 8.88mm/m2 in males; p&lt;0.001), indexed left ventricular (LV) end-diastolic volume (35.07ml/m2 in females & 41.05ml/m2 in males; p&lt;0.001) and indexed LV end-systolic volume (17.95ml/m2 in females & 21.74ml/m2 in males; p&lt;0.001) suggested a mildly worse phenotype in females. No significant differences were observed in disease progression on serial echocardiography and mortality across the overall population (p=0.459) and when divided by genotype (p=0.730 for wtATTR-CM; p=0.161 for T60A-hATTR-CM; p=0.056 for V122I-hATTR-CM).

Conclusion

This study of a well-characterized large cohort of ATTR-CM patients, contrary to previous dogmas, did not demonstrate overall differences between sexes in either clinical phenotype, when indexed, or with respect to disease progression and prognosis. The analysis highlighted the deficiencies in using non-indexed values which can not only lead to the inaccurate perception of a milder clinical phenotype in women compared to men, but has been shown to result in female patients presenting at an older age and with a worse phenotype compared to men. These findings indicate the need for revision of existing clinical guidelines regarding awareness and diagnosis of ATTR-CM in women, and modification of clinical trials which currently use single non-indexed threshold for wall thickness as key inclusion criterion.

Funding Acknowledgement

Type of funding sources: Foundation.

Valve disease in cardiac amyloidosis: an echocardiographic score

Background

Cardiac amyloidosis (CA) may affect all cardiac structures, including the valves.

Methods

From 423 patients undergoing a diagnostic workup for CA we selected 2 samples of 20 patients with amyloid transthyretin (ATTR-) or light-chain (AL-) CA, and age- and sex-matched controls. We chose 31 echocardiographic items related to the mitral, aortic and tricuspid valves, giving a value of 1 to each abnormal item.

Results

Patients with ATTR-CA displayed more often a shortened/hidden and restricted posterior mitral valve leaflet (PMVL), thickened mitral chordae tendineae and aortic stenosis than those with AL-CA, and less frequent PMVL calcification than matched controls. Score values were 15.8 (13.6–17.4) in ATTR-CA, 11.0 (9.3–14.9) in AL-CA, 12.8 (11.1–14.4) in ATTR-CA controls, and 11.0 (9.1–13.0) in AL-CA controls (p=0.004 for ATTR- vs. AL-CA, 0.009 for ATTR-CA vs. their controls, and 0.461 for AL-CA vs. controls). Area under the curve values to diagnose ATTR-CA were 0.782 in patients with ATTR-CA or matched controls, and 0.773 in patients with LV hypertrophy.

Conclusions

Patients with ATTR-CA have a prominent impairment of mitral valve structure and function, and higher score values. The valve score is quite effective in identifying patients with ATTR-CA among patients with CA or unexplained hypertrophy.

Funding Acknowledgement

Type of funding sources: None.

Prognostic implications of clinical phenotype and severity of cardiac involvement in patients presenting with immunoglobulin light chain amyloidosis

Background

Patients with systemic immunoglobulin light chain (AL) amyloidosis may present with a wide array of signs and symptoms due to the multi-systemic organ involved. The presence of cardiac involvement is the key determinant of survival. Cardiac magnetic resonance (CMR) has the unique ability to measure the continuum of cardiac amyloidosis (CA) infiltration providing a deep characterisation from early CA involvement to severe degree of CA burden.

Purpose

The aim of this study was to characterise the clinical profiles and the severity of organ involvement in patients presenting with AL amyloidosis and to investigate implications for long-term outcome.

Methods

Patients newly diagnosed with AL amyloidosis at the National Amyloidosis Centre underwent comprehensive clinical, laboratory and instrumental work up, including CMR imaging with left ventricular (LV) mass, late gadolinium enhancement (LGE) and extracellular volume (ECV). The clinical phenotypes were classified in cardiac, renal and other according to the symptoms at presentation. The degree of CA was investigated by CMR: 0= no features of CA (normal LV mass, no LGE and normal ECV); 1=early cardiac amyloid infiltration (normal LV mass, raised ECV no LGE); 2= characteristic of CA with normal mass (diffuse subendocardial or transmural LGE, altered gadolinium kinetics and raised ECV); 3= characteristic of CA with elevated mass (diffuse subendocardial or transmural LGE and raised ECV). The study outcome was all-cause mortality.

Results

The study population included 241 AL patients presenting with cardiac and renal (22.8%, n=55), cardiac (28.2%, n=68), renal (33.2%, n=80) and other (15.8% n=38) phenotypes. During a median follow up of 33 (IQR 7–52) months, cardiac phenotype either in isolation or in combination with renal phenotype was associated with a higher rate of all-cause mortality compared to the others (p&lt;0.001) (Figure). On CMR imaging, 43.2% of patients without cardiac phenotype (49%, n=118/241) had characteristic scans of CA (CMR grade 2 and 3) whilst 13.8% of patients with cardiac phenotype (51%, n=123/241) had no features of CA on CMR images (CMR grade 0) in (p&lt;0.001). With Kaplan Meier analysis, the risk of all-cause death increased in patients with characteristic features of CA on CMR scan (Figure 1) and in patients with cardiac phenotype and features of CA on CMR scans compared to the others (both p&lt;0.001) (Figure). At multivariable analysis, age at diagnosis (hazard ratio [HR] 1.03, p=0.009), clinical phenotype at presentation (HR 1.35, p=0.014) and ECV measured by CMR (HR 56, p&lt;0.001) emerged as independent prognostic parameters.

Conclusions

Patients with newly diagnosed AL amyloidosis present most frequently with renal and cardiac phenotypes. CMR detects CA in &gt;40% of patients with non-cardiac phenotype. ECV is an independent predictor of all-cause mortality across the full clinical spectrum of AL amyloidosis.

Funding Acknowledgement

Type of funding sources: None.

Myocardial ischaemia in cardiac amyloidosis: a change of perspective

Introduction

Cardiac involvement is the main driver of clinical outcomes in systemic amyloidosis; however many clinical observations are not explained by the concept of replacement of the interstitium by amyloid material. Preliminary studies support the hypothesis that myocardial ischaemia contributes to cellular damage.

Purpose

This study assesses the presence and mechanisms of myocardial ischaemia using cardiovascular magnetic resonance (CMR) with multiparametric mapping and histopathological assessment.

Methods

Ninety-two patients with cardiac amyloidosis (CA) (AL = 41, ATTR = 51) and 97 without CA (3-vessel coronary disease (3VD) = 47, unobstructed coronary arteries = 26, healthy volunteers (HV) = 24) underwent quantitative stress perfusion CMR with myocardial blood flow (MBF) mapping. Twenty-six myocardial biopsies and 3 explanted hearts with CA were analysed histopathologically.

Results

Stress MBF was severely reduced in patients with CA with lower values than patients with 3VD, unobstructed coronary arteries and HV (CA = 1.03±0.51 ml/min/g, 3VD = 1.35±0.50 ml/min/g, Unobstructed coronaries = 2.92±0.52 ml/min/g, HV = 3.14±0.69 ml/min/g; CA vs 3VD p=0.008, CA vs Unobstructed coronaries p&lt;0.001, CA vs HV p&lt;0.001). After adjustment for intracellular volume the MBF in patients with CA remained significantly lower than in HV (stress MBF/ICV: AL = 2.24±1.12, ATTR = 2.22±0.93, HV = 4.38±1.06; AL vs. ATTR p=1.000, AL vs HV p&lt;0.001, ATTR vs. HV p&lt;0.001). Myocardial perfusion reserve (MPR) was severely reduced in CA patients, compared to HV and patients with unobstructed coronary arteries, with the degree of reduction being comparable only to patients with 3VD (CA = 1.55±0.60, 3VD = 1.54±0.51, unobstructed coronaries = 2.78±0.70, HV = 4.08±0.86; CA vs 3VD p=1.000, CA vs unobstructed coronary arteries p&lt;0.001, CA vs. HV p&lt;0.001). Myocardial perfusion abnormalities correlated with amyloid burden, systolic and diastolic function, structural parameters and blood biomarkers (p&lt;0.05). Biopsies demonstrated diffuse hypoxia with abnormal VEGF staining in cardiomyocytes and endothelial cells. Amyloid infiltration in intramural arteries was associated with severe lumen reduction in 20% of vessels, and severe reduction in capillary density.

Conclusion

CA is associated with severe myocardial ischaemia demonstrable by histology and CMR stress perfusion mapping. Histological evaluation indicates a complex pathophysiology, where systolic and diastolic dysfunction, amyloid infiltration of the epicardial arteries and disruption and rarefaction of the capillaries play a role in contributing to myocardial ischaemia.

Funding Acknowledgement

Type of funding sources: None.

Changes in referral pathway and phenotypic status of patients diagnosed with ATTR cardiac amyloidosis during the past 20 years

Background

Diagnostic and therapeutic advances have led to much increased awareness of transthyretin (ATTR) cardiac amyloidosis (CA).

Purpose

We sought to characterise the impact of this on referral practice, cardiac phenotype at diagnosis and specifically to determine whether patients are now being diagnosed at an earlier stage in their disease process.

Methods

We studied 1845 patients diagnosed with ATTR-CA at the National Amyloidosis Centre (NAC) from 2002–2021, all of whom underwent deep clinical phenotyping and follow-up.

Results

Analysis by 5-year quartiles revealed a substantial incremental increase in patients diagnosed with ATTR-CA (35 vs 260 vs 704 vs 846), which was associated with greater proportions of patients referred following advanced cardiac imaging (referrals following cardiac magnetic resonance and bone scintigraphy: 3% vs 44% vs 67% vs 76%; P&lt;0.001). Over time, median duration of symptoms prior to diagnosis diminished from 36-months between 2002–2006 to 12-months between 2017–2021 (P&lt;0.001) and a greater proportion of patients presented with milder disease across the 5-yearly quartiles (NAC stage 1: 40% vs 43% vs 44% vs 57%; P&lt;0.001). The latter was associated with more favourable echocardiographic parameters of structure and function, including an incremental reduction in maximal left ventricular wall thickness (18.26mm vs 17.41mm vs 17.09mm vs 16.68mm; P=0.017). This was associated with improved survival in the overall population (2007–2011 vs 2012–2016: HR=1.65, 95% CI [1.33–2.06]; P&lt;0.001 and 2012–2016 vs 2017–2021: HR =1.83, 95% CI [1.45–2.31]; P&lt;0.001) and in each genotype (wtATTR, T60A and V122I). Despite a significant increase in the proportion of patients enrolled into clinical trials (0.0% vs 0.0% vs 2.6% vs 23.9%; P&lt;0.001) and prescribed disease modifying therapy (5.7% vs 0.4% vs 4.8% vs 13.5%; P&lt;0.001); the improved survival remained significant even after adjusting for clinical trials and disease modifying therapy (2012–2016 vs. 2017–2021: HR=1.65 95% CI [1.29–2.11], P&lt;0.001).

Conclusion

Increased awareness and advances in cardiac imaging have been associated with a substantial increase in the diagnosis of ATTR-CA and at a progressively earlier stage of the disease, which has contributed to improved survival in recent years. These changes may have important implications for initiation and outcome of therapy. Given that ATTR-CA is now being diagnosed earlier, more data are needed to guide decisions on in whom and when to initiate treatment, and which treatments should be used at each disease stage. Furthermore, the changes in ATTR-CA phenotype at diagnosis urgently need to be factored into clinical trial design, given that pre-determined end-points based on trials performed in the past may no longer be appropriate, or at least sufficiently powered, or of adequate duration to evaluate efficacy of novel agents.

Funding Acknowledgement

Type of funding sources: None.

Cardiac transplantation in transthyretin amyloid cardiomyopathy: outcomes from three decades of tertiary centre experience

Background

Transthyretin cardiac amyloidosis (ATTR-CM) is a progressive and fatal cardiomyopathy. Treatment options in patients with advanced heart failure are limited to cardiac transplantation (CT). Despite small case series demonstrating comparable outcomes with CT between patients with ATTR-CM and non-amyloid cardiomyopathies, ATTR-CM is considered to be an absolute contraindication to CT in some centres. This is in part due to a perceived risk of amyloid recurrence in the cardiac allograft. We report outcomes of patients with ATTR-CM assessed at our centre whom underwent CT over the past thirty years.

Methods

We retrospectively evaluated all ATTR-CM patients assessed at the UK National Amyloidosis Centre between 1990 and 2020 who underwent CT. Pre-transplantation disease and patient characteristics were determined and outcomes were compared with our large cohort of non-transplanted ATTR-CM patients. Censor date was 11th January 2022.

Results

Eleven (9 male, 2 female) patients with ATTR-CM underwent CT including 8 with wild-type ATTR-CM and 3 with variant ATTR-CM (ATTRv). Median age at CT was 60.3 years and median follow up post-CT was 65.7 months. Median (range) NT-proBNP concentration pre-transplant was 4478ng/L (1057–8778ng/L), median (range) left ventricular ejection fraction (LVEF) was 39% (27–56%) and mean (IQR) interventricular septal (IVSD) was 18 mm (15.9–20.1 mm). 8 patients were NYHA functional class III, the 3 remaining patients were class II.

One, three, and five-year survival was 100%, 89% and 86%, respectively and the longest surviving patient was censored &gt;19 years post CT. Survival is at least comparable to UK and US CT outcome registry data for all non-amyloid patients undergoing CT. No patients had recurrence of amyloid in the cardiac allograft as assessed by endomyocardial biopsy and/or Tc-DPD scintigraphy. Two patients were commenced on Patisiran for amyloid polyneuropathy at 211 and 5 months post-CT. Graft rejection requiring treatment was observed in 2 patients, and successfully treated with intravenous steroids. Renal impairment was common, with 6 patients being left with chronic kidney disease.

Three patients died, including one with ATTRv-CM from complications of leptomeningeal amyloidosis. Survival among the cohort of patients who underwent CT was significantly longer than UK patients with ATTR-CM generally (P≤0.006), regardless of NAC ATTR disease stage and including those diagnosed under 65 years of age (P=0.028). (Figure 1) All surviving patients were NYHA functional class I at time of censor.

Conclusion

Our data indicates that cardiac transplantation is well tolerated, restores functional capacity, and prolongs survival in ATTR-CM with little risk of recurrence of amyloid in the cardiac allograft. We believe that our data argues strongly for ATTR-CM to be routinely included in the list of indications for cardiac transplantation.

Funding Acknowledgement

Type of funding sources: None.

A multi-modality, multi-parametric phenotyping study of transthyretin amyloid cardiomyopathy associated with the p.V142I TTR variant

Introduction

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an increasingly recognised cause of heart failure. 3–4% of individuals of African descent carry a transthyretin gene mutation encoding the p.V142I variant, a powerful risk factor for development of variant ATTR-CM. This equates to 1.6 million potential carriers in the USA alone. We report findings from a multi-parametric, multi-modality phenotyping study of p.V142I ATTR-CM.

Hypothesis

The phenotype of p.V142I variant ATTR-CM is an aggressive form of ATTR CM.

Methods

A retrospective phenotyping study of 395 patients with p.V142I-ATTR-CM at our national referral centre was conducted. Patients underwent evaluation at the centre at time of diagnosis, including clinical and functional assessment, echocardiography, biomarker analysis; a subgroup had cardiac magnetic resonance imaging. 395 wild type ATTR-CM patients matched for independent predictors of prognosis (NAC Disease Stage, age, decade of first presentation) were used as a comparator group.

Results

Average age of pV142I ATTR-CM patients was 75.8 years. There was significant functional impairment (38.2% of cases NHYA ≥ III, mean 6 minute walk test distance 272m). Significant impairment of echocardiographic parameters was seen; mean LVEF 43%, global longitudinal strain −9.1%, TAPSE 14.2mm, E/E prime 17.4, E/A ratio 2.47 with high frequency of at least moderate mitral (44%) and tricuspid regurgitation (51%). Median NT-proBNP was 3165 ng/L (IQR 4224). Arrhythmias were common with 17.4% of patients having a bradyarrhythmia, 26.1% having atrial fibrillation/flutter, and 5.6% having a pacemaker at presentation. Uni and multivariate cox regression analysis identified serum troponin, tricuspid regurgitation, LVEF, TAPSE and lower systolic blood pressure as independent predictors of prognosis. Prognostic parameters were statistically significantly worse and five year survival by Kaplan Meier analysis was significantly reduced when compared to matched WT ATTR-CM patients (p&lt;0.05) (Figure 1).

Mean serum high sensitivity troponin T and extracellular volume (ECV) by cardiac magnetic resonance (CMR) was higher in p.V142I ATTR-CM than WT ATTR-CM cases (94 ng/L vs 74.2 ng/L, p&lt;0.05, 58% vs 55%, p&lt;0.05). Interventricular wall thickness however was lower in p.V142I ATTR-CM than matched WT cases (17.2 mm vs 16.8 mm).

Conclusion

p.V142I ATTR-CM is an aggressive phenotype, with significant functional impairment, burden of regurgitant valvular disease and systolic impairment resulting in poor survival.

Patients with p.V142I ATTR-CM had a higher burden of amyloid infiltration as measured as shown by ECV measurements on CMR, higher serum troponin and lower wall thickness when compared to a matched cohort of WT ATTR-CM patients. This novel observation suggests a unique disease mechanism that is more cardiotoxic which results in myocyte loss and myocardial thinning as opposed to myocyte hypertrophy.

Funding Acknowledgement

Type of funding sources: None.

Extracellular volume fraction by computed tomography predicts long-term prognosis among patients with cardiac amyloidosis

Objective

This study sought to investigate the association of extracellular volume fraction by computed tomography (ECVCT), myocardial remodeling and mortality in patients with systemic amyloidosis.

Background

Light chain (AL) and transthyretin (ATTR) amyloid fibrils are deposited in the extracellular space of the myocardium, resulting in heart failure and premature mortality. Extracellular expansion can be quantified by CT, offering a rapid and cost-effective alternative to cardiovascular magnetic resonance (CMR), especially among patients with cardiac devices or on renal dialysis.

Methods

Patients with confirmed systemic amyloidosis and varying degrees of cardiac involvement underwent ECG-gated cardiac CT. ECVCT was analysed in the inter-ventricular septum. All patients also underwent clinical assessment, ECG, echocardiography, serum amyloid protein component (SAP) and/or technetium-99m (99mTc) 3,3-diphosphono-1,2-propanodicarboxylic acid scintigraphy. ECVCT was compared across different extents of cardiac infiltration (ATTR Perugini Grade / AL Mayo Class) and evaluated for its association with myocardial remodelling and all-cause mortality.

Results

72 patients were studied (AL n=35, ATTR n=37; age 67 (59–76) years, 71% males). Mean septal ECVCT was 42.7±13.1% and 55.8±10.9% in AL and ATTR, respectively, and correlated with indexed left ventricular (LV) mass (r=0.426, p&lt;0.001), LV ejection fraction [LVEF, (r=0.460, p&lt;0.001)], NT-proBNP (r=0.563, p&lt;0.001) and hsTnT (r=0.546, p=0.02). ECVCT increased with cardiac amyloid involvement in both AL and ATTR (Figure 1). Over a mean follow-up of 5.3±2.4 years, 40 deaths occurred (AL 14 [35%]; ATTR 26 [65%]). ECVCT was independently associated with all-cause mortality in ATTR (not AL) after adjustment for age and IV septal wall thickness (HR: 1.046, 95% CI: 1.003–1.090, p=0.037).

Conclusion

Cardiac amyloid burden quantified by ECVCT is associated with adverse cardiac remodelling as well as all-cause mortality among ATTR amyloid patients. ECVCT may address the need for better identification and risk stratification of amyloid patients, using a widely-accessible imaging modality (Figure 2).

Funding Acknowledgement

Type of funding sources: None.

Progression, regression and redefining the treatment response – cardiac magnetic resonance with T1 and extracellular volume mapping in cardiac light-chain amyloidosis

Background

The presence and severity of cardiac involvement in AL amyloidosis is the main driver of prognosis [1]; patients with symptomatic heart failure frequently die within 6 months [1] but median survival has nearly doubled over the past decade, mainly due to significant improvements in chemotherapy. The haematological response to chemotherapy is principally evaluated with serial measurements of serum-free light-chains (FLC) [2]. The cardiac response to chemotherapy is assessed through changes in serum concentrations of brain natriuretic peptides (including NT-proBNP) and echocardiographic parameters [3–5]. Neither are able to directly measure cardiac amyloid burden. Cardiovascular magnetic resonance (CMR) with extra-cellular volume (ECV) mapping can measure the extent cardiac amyloid infiltration [6].

Aims

We investigated the ability of CMR to: 1) measure changes in response to chemotherapy; 2) assess the correlation between haematological response (HMR) and changes in cardiac amyloid; 3) assess the association between changes in cardiac amyloid and prognosis over and above existing predictors.

Methods

In total, 176 patients with cardiac light-chain amyloidosis treated with chemotherapy were assessed with FLC, NT-proBNP and CMR with ECV mapping at baseline (before chemotherapy), 6-months, 12-months & 24-months after commencing chemotherapy. Haematological response was categorized by reductions in FLC as: complete response (CR), very good partial response (VGPR), partial response (PR) or no response (NR). CMR response was categorized by changes in ECV as: progression (≥0.05 increase), stable (&lt;0.05 change) or regression (≥0.05 decrease).

Results

A progressive increase in patients achieving either CR or VGPR was observed at each time point (61% of patients at 6-months, 71% at 12-months and 80% at 24-months). At 6-months, CMR regression was observed in 3% (all had either CR or VGPR) and progression in 32% (61% had either PR or NR; 39% had either CR or VGPR). At 1-year, CMR regression was observed in 22% (all had either CR or VGPR); progression in 22% (63% had either PR or NR; 37% had either CR or VGPR). At 2-years, CMR regression was observed in 38% (all had CR/VGPR); progression in 14% (80% had either PR or NR; 20% had either CR or VGPR). During follow-up (40±15 months), 36 (25%) patients died. CMR response at 6-months predicted death (progression HR 3.821; 95% CI 1.950–7.487; p&lt;0.001) and remained independently associated with prognosis after adjusting for haematological response, NT-proBNP and longitudinal strain on echocardiography (p&lt;0.01).

Conclusions

CMR demonstrates that cardiac amyloid deposits frequently regress following chemotherapy, but only in patients who achieve CR or VGPR, highlighting the need for deep haematological response. Changes in amyloid burden (ECV) predict outcomes after adjusting for known predictors, showing the crucial role of CMR in redefining treatment response.

Funding Acknowledgement

Type of funding sources: Foundation.

Quantitative myocardial blood flow as a prognostic marker for cardiovascular outcomes in patients with Type 2 Diabetes Mellitus: a multicentre study

 

Introduction: Patients with Type 2 Diabetes Mellitus (T2DM) are at increased risk of cardiovascular disease, including epicardial coronary heart disease, silent myocardial infarction (MI), and coronary microvascular dysfunction (CMD) [1]. All of these can be assessed and quantified using cardiac magnetic resonance (CMR), including most recently quantitative myocardial blood flow (MBF). We aimed to determine the prognostic relevance of MBF in patients with T2DM and test the hypothesis that impaired stress MBF and myocardial perfusion reserve (MPR) have independent prognostic value over standard clinical and imaging parameters.

Methods

A 4-centre study of patients with T2DM who underwent quantitative perfusion assessment using CMR. Diagnosis of T2DM was based on Hba1c &gt;48mmol/l or a known diagnosis of T2DM. Image analysis was performed automatically using an artificial intelligence approach deriving global MBF and MPR [2]. Cox proportional hazard models adjusting for comorbidities and CMR parameters sought associations between stress MBF and MPR with death and major adverse cardiovascular events (MACE), including MI, non-fatal stroke, heart failure hospitalisation and death.

Results

A total of 630 patients with T2DM were included with a median follow-up of 722 days (interquartile range 493) days. There were 27 (4.3%) deaths and 76 MACE events in 62 (12.1%) patients. Patient data was represented into groups depending on threshold stress MBF values of 1.94ml/g/min and MPR thresholds of 1.96 using validated data from invasive coronary physiology [3]. Patient demographics and CMR data are seen in table 1. Kaplan-Meier curves are seen in figure 1. Stress MBF was associated with mortality and MACE after adjusting for age, LV ejection fraction and HbA1c. The stress MBF adjusted hazard ratios for all cause death and death and MACE were 0.35 (95% CI, 0.13–0.95, P=0.04) and 0.54 (95% CI, 0.30–0.96, P=0.04), respectively. MPR was not significantly associated with death and MACE after adjusting for age, LV ejection fraction and HbA1c; hazard ratio for all cause death and death and MACE was 0.83 (95% CI, 0.41–1.69, P=0.60) and 0.81 (95% CI, 0.53–1.23, p=0.32) respectively.

Conclusion

In patients with T2DM, reduced stress MBF measured automatically inline using artificial intelligence quantification of cardiovascular magnetic resonance perfusion mapping provides a strong, independent predictor of adverse cardiovascular outcome.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): 1. REC ID 14/EE/0007 (Barts Heart Centre funding). 2. For PREDICT (Leicester data) ethical approval was provided by the UK Health Research Authority Research Ethics Committee (reference 17/WM/0192). 3. MATCH Study, Leeds - British Heart Foundation - 17/YH/0300. 4. LEAN-DM, Leeds - British Heart Foundation - 18/YH/01685. CEED, Leeds: British Heart Foundation - REC reference - 18/YH/0190

Multi-imaging characterisation of cardiac phenotype in different types of amyloidosis

Background

Bone scintigraphy is extremely valuable when assessing patients with suspected cardiac amyloidosis (CA), but the clinical significance and associated phenotype of different degrees of myocardial tracer uptake across different types of amyloidosis is yet to be defined.

Purpose

We sought to define the phenotypes of patients with varying degrees of cardiac uptake on bone scintigraphy, across multiple types of systemic amyloidosis using extensive characterisation comprising of biomarkers, echocardiographic and cardiac magnetic resonance (CMR) imaging.

Methods

A total of 296 patients (117 immunoglobulin light-chain [AL] amyloidosis, 165 transthyretin [ATTR] amyloidosis, 7 apolipoprotein-A1-amyloidosis [AApoAI],and 7 apolipoprotein-A4-amyloidosis [AApoA4]) underwent deep characterisation of their cardiac phenotype.

Results

AL-amyloidosis patients with grade 0 myocardial radiotracer uptake spanned the spectrum of CMR findings from no evidence of CA to characteristic features of CA, while AL-amyloidosis patients with grade 1–3 always produced characteristic CMR features. In ATTR-amyloidosis the CA burden strongly correlated with myocardial tracer uptake (correlation between bone scintigraphy cardiac uptake and CMR derived extracellular volume: R=0.88, 95% CI [0.84–0.91], P&lt;0.001), except in patients with the Ser77Tyr variant. AApoAI-amyloidosis presented with grade 0–1 myocardial tracer uptake, and unique features of disproportionate right sided involvement such as disproportionate right ventricular (RV) and right atrial uptake on bone scintigraphy, RV free wall thickening, and tricuspid valve thickening and dysfunction. Within our cohort, AApoAIV-amyloidosis always presented with grade 0 myocardial tracer uptake, and characteristic features of CA on CMR. All AL-amyloidosis patients with grade 1 myocardial tracer uptake had characteristic CMR features of CA (n=48, 100%), while only ATTR-amyloidosis grade 1 patients with the Ser77Tyr variant had characteristic features of CA on CMR (n=5, 11.4%). Following the exclusion of Ser77Tyr and AApoAI, a CMR showing characteristic features of CA or an extracellular volume &gt;0.40 in a patient with grade 1 myocardial tracer uptake had a sensitivity and specificity of 100% for diagnosing AL-amyloidosis.

Conclusion

Deep characterisation of the cardiac phenotype in different types of amyloidosis, across a range of bone scintigraphy cardiac uptake grades has identified clear differences between each amyloidosis type. The distinctive characteristics in each cohort has allowed the development of a diagnostic pathway to help define the diagnostic differentials and the clinical phenotype in each individual patient, following comprehensive assessment with bone scintigraphy and CMR.

Funding Acknowledgement

Type of funding sources: None.

NNC6019–0001, a humanized monoclonal antibody, in patients with transthyretin amyloid cardiomyopathy (ATTR-CM): rationale and study design of a phase 2, randomized, placebo-controlled trial

Introduction

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a chronic condition associated with progressive heart failure, resulting from extracellular deposition of misfolded transthyretin (TTR) protein as amyloid fibrils in the myocardium. Currently, there are few disease-modifying treatments. NNC6019–0001 is a humanized monoclonal antibody designed to deplete amyloid via antibody-mediated phagocytosis by targeting a unique epitope that is exposed only on misfolded monomeric and aggregated forms of TTR. In a phase 1, open-label, 3-month dose escalation trial, NNC6019–0001 was well tolerated at all doses tested (up to and including 30 mg/kg).1 The maximum tolerated dose was not reached. Exploratory cardiac endpoints were stable or indicated a possible benefit.

Purpose

To evaluate the effect of NNC6019–0001 30 mg/kg and 100 mg/kg on cardiac functional endpoints and predictive biomarkers in patients with ATTR-CM, and to assess pharmacokinetics, safety and tolerability, to establish the optimal dose for a phase 3 trial.

Methods

This is a randomized, double-blind, placebo-controlled trial recruiting 99 patients with hereditary or wild-type ATTR-CM (Figure). Inclusion criteria are New York Heart Association (NYHA) class II or III heart failure, left ventricle wall thickening (LVWT) ≥12 mm, N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels ≥650 pg/mL in sinus rhythm and &gt;1000 pg/mL in atrial fibrillation, and a 6-minute walk test (6MWT) distance of 150–450 m. Patients will be randomly assigned to receive intravenous NNC6019–0001 30 mg/kg or 100 mg/kg or placebo, each in addition to standard of care, every 4 weeks for 52 weeks, followed by a 12-week follow-up. In a sentinel dosing phase, three patients per arm will receive the study drug or placebo, in combination with 24-hour inpatient cardiac monitoring and 7 days of continuous cardiac (tele-) monitoring. The primary endpoints are change from baseline to week 52 in 6MWT and in NT-proBNP levels. Secondary endpoints include cardiac measures: extracellular volume on cardiac magnetic resonance imaging, global longitudinal strain, troponin T levels, hospitalization due to cardiovascular events, and urgent visits due to heart failure. Quality of life will be assessed using the Kansas City Cardiomyopathy Questionnaire (KCCQ). All-cause mortality, pharmacokinetics and treatment-emergent adverse events will also be assessed.

Results

The trial will start mid-2022 with global recruitment.

Conclusion

Disease-modifying treatments are needed for patients with ATTR-CM, where treatment is often limited to managing symptoms and best supportive care; the first disease-modifying therapies recently became available. This phase 2 trial will be used to determine the appropriate dose for the phase 3 trial of NNC6019–0001, a novel antibody therapy designed to deplete amyloid in patients with ATTR-CM.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This trial was funded by Novo Nordisk A/S. Medical writing support was provided by Johanna Scheinost PhD, PharmaGenesis Oxford Central, Oxford, UK, with funding from Novo Nordisk A/S.

First Measurement of the Z→μ^{+}μ^{-} Angular Coefficients in the Forward Region of pp Collisions at sqrt[s]=13 TeV

The first study of the angular distribution of μ^{+}μ^{-} pairs produced in the forward rapidity region via the Drell-Yan reaction pp→γ^{*}/Z+X→ℓ^{+}ℓ^{-}+X is presented, using data collected with the LHCb detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.1  fb^{-1}. The coefficients of the five leading terms in the angular distribution are determined as a function of the dimuon transverse momentum and rapidity. The results are compared to various theoretical predictions of the Z-boson production mechanism and can also be used to probe transverse-momentum-dependent parton distributions within the proton.

Convolutional neural network transformer (CNNT) for free-breathing real-time cine imaging

Funding Acknowledgements

Type of funding sources: None.

Background

Real-time cine imaging does not require breath-holding and is a robust cine imaging technique in the presence of irregular heartbeats. It is a good alternative to the conventional breath-hold retro-gated cine for simplified acquisition and improved patient comfort. Real-time acquisition is achieved with the single-shot BSSFP readout without retro-gating. To maintain good temporal and spatial resolution, higher acceleration (e.g. &gt;4x parallel imaging) is required. As a result, the real-time cine images experience reduced signal-to-noise ratio (SNR), which limits its clinical acceptance.

Purpose

We developed a novel deep learning model architecture, the Convolutional Neural Network Transformer (CNNT), to improve the quality of real-time cine, under 4x, 5x and 6x acceleration.

Method

Convolutional Neural Networks (CNN) are widely used in CMR research to process cardiac images. Cardiac images are often acquired as a time series with strong inter-phase correlation. We combined the CNN with the more recent transformer model to develop a novel CNNT architecture. It takes in the entire 2D+T time series as input and has advantages of CNN for efficient computation and spatial invariance. It further inherits the advantages of attention layer in the transformer and is able to efficiently utilize the temporal correlation within a time series.

A CNNT model is developed to improve the SNR of real-time cine imaging. N=10 patients were scanned at a heart center, with 4x, 5x and 6x acceleration. Typical imaging parameters are: FOV 360×270mm2, flip angle 50°, acquired matrix size 160×90 for R=4 acceleration, 192×108 for R=5 and 6, temporal resolution 40ms for R=4, 42ms for R=5 and 35ms for R=6. The real-time images went through a TGRAPPA reconstruction [1] and the CNNT model. The SNR of TGRAPPA was measured with SNR units [2]. The Monte-Carlo pseudo-replica test was used to measure SNR for the CNNT model. For every cine series, two phases were picked for the end-systole and end-diastole. For every image picked, two region-of-interests were drawn in the myocardium and in the LV blood pool. The CNNT model was deployed inline on the MR scanner using the Gadgetron InlineAI [3].

Results

Figure 1 gives real-time cine images for three accelerations, reconstructed with TGRAPPA and CNNT. The parallel imaging TGRAPPA reconstruction suffers significant SNR loss from elevated g-factor and less acquired data. The deep learning CNNT model recovered SNR even at the very high 6x acceleration, without observed loss of boundary sharpness.

Table 1 lists the SNR measurement results. The TGRAPPA SNR decreased ∼4x from R=4 to R=6 for both the blood and myocardium. For the blood, the CNNT increased the SNR by 170%, 335%, 371% at R=4, 5 and 6. For the myocardium, the SNR increases were 335%, 634% and 828%.

Conclusion

We developed a convolutional neural network transformer model to recover the SNR for real-time cine imaging at higher acceleration.

CNNT DB-LGE: free-breathing dark blood late enhancement imaging using the convolutional neural network transformer speeds acquisition by 50%

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Supported in part by the Division of Intramural Research of the National Heart, Lung, and Blood Institute, National Institutes of Health (grants Z1A-HL006214-05 and Z1A-HL006242-02).

Background

Dark blood late gadolinium enhancement (DB-LGE) imaging shows superior delineation of myocardial infarction (MI), especially at the sub-endocardial boundary. Our previous study [1] developed a free-breathing DB-LGE with the single shot SSFP readout, phase sensitive inversion recovery (PSIR) reconstruction, and respiratory motion corrected averaging. To compensate the potential signal-to-noise ratio loss, our previous DB-LGE doubled the measurements, thereby increasing the acquisition time.

Purpose

In this study, we developed a deep learning image enhancement model using a novel neural network architecture called the convolutional neural network transformer (CNNT) to improve the image quality of DB-LGE and to reduce the acquisition time by decreasing the number of measurements.

Methods

A novel image enhancement model was developed using a novel network architecture called the Convolutional Neural Network Transformer (CNNT) proposed by us. This architecture is suitable for the 2D+Time CMR acquisition, by exploiting the temporal correlation between images over multiple averages.

The evaluation was first retrospectively conducted on a cohort of 12 patients acquired with the original protocol [1] using the full 16 measurements. For every subject, a complete short-axis stack (typically 12 slices) was acquired to cover the entire left ventricular. The imaging data was reconstructed in three ways. Original: using all acquired 16 measurements. This is our base-line protocol. Original 50%: using only the first 8 measurements. CNNT 50%: using only the first 8 averages, but performing the CNNT deep learning image enhancement before MOCO PSIR reconstruction. Two experienced imaging researchers (PK and MF, &gt;10 years of experience for both) scored all DB-LGE images for the overall quality, diagnostic confidence and delineation of MI/boundaries (5 = excellent, 4 = good, 3 = fair, 2 = poor, and 1 = non-diagnostic). The CNNT DB-LGE was deployed to the MR scanner using the Gadgetron InlineAI [2].

Results

Figure 1 gives examples of DB-LGE with three reconstruction methods. The CNNT image has higher SNR and well delineated MI. The Original images with the longest acquisition have good quality and the Original-50% acquired with 8 measurements are good quality but have reduced SNR. The mean scores for overall image quality, diagnostic confidence and MI delineation of two reviewers were 4.88±0.23, 4.88±0.23, 4.83±0.25 for CNNT and 4.96±0.14, 4.96±0.14, 4.67±0.39 for the original approach. No significant differences were found between the original and the CNNT (P&gt;0.15 for all).

Figure 2 shows an acute MI patient prospectively acquired with the 50% scan time reduction, with and without the CNNT enhancement. The resulting PSIR images well delineate the MVO due to the acute MI, with improved SNR.

Conclusion

A novel CNNT model was proposed and evaluated to speed up the free-breathing MOCO DB LGE by 50% without sacrificing image quality.

Concurrent validity of the short-form Family Impact Scale (FIS-8) in 4-year-old US children

Background

US data on the validity and reliability of the short-form Family Impact Scale (FIS-8; a scale for measuring the impact of a child’s oral condition on his/her family) are lacking.

Methods

Cross-sectional analysis of data on four-year-old US children taking part in a multi-center cohort study. For child-caregiver dyads recruited at child age 12 months, the impact of the child’s oral condition on the family was assessed at age 48 months using the FIS-8, with a subsample of 422 caregivers (from 686 who were approached). Internal consistency reliability was assessed using Cronbach’s α, with concurrent validity assessed against a global family impact item (“How much are your family’s daily lives affected by your child’s teeth, lips, jaws or mouth?”) and a global oral health item (“How would you describe the health of your child’s teeth and mouth?”).

Results

Cronbach’s alpha was 0.83. Although gradients in mean scores across ordinal response categories of the global family impact item were inconsistent, there were marked, consistent gradients across the ordinal categories of the global item on the child’s oral health, with scores highest for those rating their child’s oral health as ‘Poor’.

Conclusions

While the findings provide some evidence for the utility of the FIS in a US child sample, the study’s replication in samples of preschoolers with greater disease experience would be useful.

Study of the doubly charmed tetraquark [Formula: see text]

Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar [Formula: see text] tetraquark with a quark content of [Formula: see text] and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector [Formula: see text] state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the [Formula: see text] state. In addition, an unexpected dependence of the production rate on track multiplicity is observed.

Angular Analysis of D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} Decays and Search for CP Violation

The first full angular analysis and an updated measurement of the decay-rate CP asymmetry of the D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} decays are reported. The analysis uses proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. The dataset corresponds to an integrated luminosity of 9  fb^{-1}. The full set of CP -averaged angular observables and their CP asymmetries are measured as a function of the dimuon invariant mass. The results are consistent with expectations from the standard model and with CP symmetry.