35 research outputs found

    Endomyocardial fibrosis of the right ventricle

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    Endomyocardial fi brosis is a rare cause of restrictive cardiomyopathy which predominates in lowincome population living in tropical areas. ItÂŽs characterized by endomyocardial fi brous tissue deposition causing restrictive physiology with poor prognosis without proper management. We present a 40-yearold woman with right ventricular endomyocardial fi brosis complicated by pericardial effusion and a giant atrial thrombus. The use of multimodal imaging is very important for the diagnosis of this extremely rare pathology in our country.</p

    Vasodilator Strain Stress Echocardiography in Suspected Coronary Microvascular Angina

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    Background: In patients with Ischemia and non-obstructive coronary artery stenosis (INOCA) wall motion is rarely abnormal during stress echocardiography (SE). Our aim was to determine if patients with INOCA and reduced coronary flow velocity reserve (CVFR) have altered cardiac mechanics using two-dimensional speckle-tracking echocardiography (2DSTE) during SE. Methods: In a prospective, multicenter, international study, we recruited 135 patients with INOCA. Overall, we performed high dose (0.84 mg/kg) dipyridamole SE with combined assessment of CVFR and 2DSTE. The population was divided in patients with normal CVFR (>2, group 1, n = 95) and abnormal CVFR (≀2, group 2, n = 35). Clinical and 2DSTE parameters were compared between groups. Results: Feasibility was high for CFVR (98%) and 2DSTE (97%). A total of 130 patients (mean age 63 ± 12 years, 67 women) had complete flow and strain data. The two groups showed similar 2DSTE values at rest. At peak SE, Group 1 patients showed lower global longitudinal strain (p p p p Conclusions: In patients with INOCA, vasodilator SE with simultaneous assessment of CFVR and strain is highly feasible. Coronary microvascular dysfunction is accompanied by an impairment of global and layer-specific deformation indices during stress

    Vasodilator Strain Stress Echocardiography in Suspected Coronary Microvascular Angina

    No full text
    Background: In patients with Ischemia and non-obstructive coronary artery stenosis (INOCA) wall motion is rarely abnormal during stress echocardiography (SE). Our aim was to determine if patients with INOCA and reduced coronary flow velocity reserve (CVFR) have altered cardiac mechanics using two-dimensional speckle-tracking echocardiography (2DSTE) during SE. Methods: In a prospective, multicenter, international study, we recruited 135 patients with INOCA. Overall, we performed high dose (0.84 mg/kg) dipyridamole SE with combined assessment of CVFR and 2DSTE. The population was divided in patients with normal CVFR (&gt;2, group 1, n = 95) and abnormal CVFR (&le;2, group 2, n = 35). Clinical and 2DSTE parameters were compared between groups. Results: Feasibility was high for CFVR (98%) and 2DSTE (97%). A total of 130 patients (mean age 63 &plusmn; 12 years, 67 women) had complete flow and strain data. The two groups showed similar 2DSTE values at rest. At peak SE, Group 1 patients showed lower global longitudinal strain (p &lt; 0.007), higher mechanical dispersion (p &lt; 0.0005), lower endocardial (p &lt; 0.001), and epicardial (p &lt; 0.0002) layer specific strain. Conclusions: In patients with INOCA, vasodilator SE with simultaneous assessment of CFVR and strain is highly feasible. Coronary microvascular dysfunction is accompanied by an impairment of global and layer-specific deformation indices during stress

    Study of b−b-hadron decays to Λc+h−hâ€Č−\Lambda_c^+h^-h^{\prime -} final states

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    Decays of Ξb−\Xi_{b}^{-} and Ωb−\Omega_{b}^{-} baryons to Λc+h−hâ€Č−\Lambda_{c}^{+} h^- h^{\prime -} final states, with h−hâ€Č−h^- h^{\prime -} being π−π−\pi^{-}\pi^{-}, K−π−K^{-}\pi^{-} and K−K−K^{-}K^{-} meson pairs, are searched for using data collected with the LHCb detector. The data sample studied corresponds to an integrated luminosity of 8.7fb−18.7 \rm fb^{-1} of pppp collisions collected at centre-of-mass energies s=7\sqrt{s} = 7, 88 and 13TeV13 \rm TeV. The products of the relative branching fractions and fragmentation fractions for each signal mode, relative to the B−→Λc+pˉπ−B^{-} \rightarrow \Lambda_{c}^{+} \bar{p} \pi^{-} mode, are measured, with Ξb−→Λc+K−π−\Xi_{b}^{-} \rightarrow\Lambda_{c}^{+} K^{-} \pi^{-}, Ξb−→Λc+K−K−\Xi_{b}^{-} \rightarrow\Lambda_{c}^{+} K^{-} K^{-} and Ωb−→Λc+K−K−\Omega_{b}^{-} \rightarrow\Lambda_{c}^{+} K^{-} K^{-} decays being observed at over 5 σ5\,\sigma significance. The Ξb−→Λc+K−π−\Xi_{b}^{-} \rightarrow\Lambda_{c}^{+} K^{-} \pi^{-} mode is also used to measure the Ξb−\Xi_{b}^{-} production asymmetry, which is found to be consistent with zero. In addition, the B−→Λc+pˉK−B^{-} \rightarrow \Lambda_{c}^{+} \bar{p} K^{-} decay is observed for the first time, and its branching fraction is measured relative to that of the B−→Λc+pˉπ−B^{-} \rightarrow \Lambda_{c}^{+} \bar{p} \pi^{-} mode.Decays of Ξb−\Xi_b^- and Ωb−\Omega_b^- baryons to Λc+h−hâ€Č−\Lambda_c^+ h^- h^{\prime -} final states, with h−hâ€Č−h^- h^{\prime -} being π−π−\pi^-\pi^-, K−π−K^-\pi^- and K−K−K^-K^- meson pairs, are searched for using data collected with the LHCb detector. The data sample studied corresponds to an integrated luminosity of 8.7 fb−18.7\,\mathrm{fb}^{-1} of pppp collisions collected at centre-of-mass energies s=7\sqrt{s} = 7, 88 and 13 TeV13\,\mathrm{Te\kern -0.1em V}. The products of the relative branching fractions and fragmentation fractions for each signal mode, relative to the B−→Λc+p‟π−B^- \to \Lambda_c^+ \overline{p} \pi^- mode, are measured, with Ξb−→Λc+K−π−\Xi_{b}^- \to\Lambda_{c}^+ K^- \pi^-, Ξb−→Λc+K−K−\Xi_{b}^- \to\Lambda_{c}^+ K^- K^- and Ωb−→Λc+K−K−\Omega_{b}^- \to\Lambda_{c}^+ K^- K^- decays being observed at over 5 σ5\,\sigma significance. The Ξb−→Λc+K−π−\Xi_{b}^- \to\Lambda_{c}^+ K^- \pi^- mode is also used to measure the Ξb−\Xi_{b}^- production asymmetry, which is found to be consistent with zero. In addition, the B−→Λc+p‟K−B^- \to \Lambda_{c}^+ \overline{p} K^- decay is observed for the first time, and its branching fraction is measured relative to that of the B−→Λc+p‟π−B^- \to \Lambda_{c}^+ \overline{p} \pi^- mode

    Tracking of charged particles with nanosecond lifetimes at LHCb

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    A method is presented to reconstruct charged particles with lifetimes between 10 ps and 10 ns, which considers a combination of their decay products and the partial tracks created by the initial charged particle. Using the Ξ−\Xi^- baryon as a benchmark, the method is demonstrated with simulated events and proton-proton collision data at s=13\sqrt{s}=13 TeV, corresponding to an integrated luminosity of 2.0 fb−1{}^{-1} collected with the LHCb detector in 2018. Significant improvements in the angular resolution and the signal purity are obtained. The method is implemented as part of the LHCb Run 3 event trigger in a set of requirements to select detached hyperons. This is the first demonstration of the applicability of this approach at the LHC, and the first to show its scaling with instantaneous luminosity

    Search for the Bs0→Ό+ÎŒâˆ’ÎłB_s^0 \rightarrow \mu^+\mu^-\gamma decay

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    International audienceA search for the fully reconstructed Bs0→Ό+ÎŒâˆ’ÎłB_s^0 \rightarrow \mu^+\mu^-\gamma decay is performed at the LHCb experiment using proton-proton collisions at s=13\sqrt{s}=13 TeV corresponding to an integrated luminosity of 5.4 fb−15.4\,\mathrm{fb^{-1}}. No significant signal is found and upper limits on the branching fraction in intervals of the dimuon mass are set \begin{align} {\cal B}(B_s^0 \rightarrow \mu^+\mu^-\gamma) < 4.2\times10^{-8},~&m(\mu\mu)\in[2m_\mu,~1.70]\,\mathrm{GeV/c^2} ,\nonumber {\cal B}(B_s^0 \rightarrow \mu^+\mu^-\gamma) < 7.7\times10^{-8},~&m(\mu\mu)\in[1.70,~2.88]\,\mathrm{GeV/c^2},\nonumber {\cal B}(B_s^0 \rightarrow \mu^+\mu^-\gamma) < 4.2\times10^{-8},~&m(\mu\mu)\in[3.92 ,~m_{B_s^0}]\,\mathrm{GeV/c^2},\nonumber \end{align} at 95% confidence level. Additionally, upper limits are set on the branching fraction in the [2mÎŒ, 1.70] GeV/c2[2m_\mu,~1.70]\,\mathrm{GeV/c^2} dimuon mass region excluding the contribution from the intermediate ϕ(1020)\phi(1020) meson, and in the region combining all dimuon-mass intervals

    First observation of Λb0→Σc(∗)++D(∗)−K−\Lambda_{b}^{0} \rightarrow \Sigma_c^{(*)++} D^{(*)-} K^{-} decays

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    International audienceThe four decays, Λb0→Σc(∗)++D(∗)−K−\Lambda_{b}^{0} \rightarrow \Sigma_c^{(*)++} D^{(*)-} K^{-}, are observed for the first time using proton-proton collision data collected with the LHCb detector at a centre-of-mass energy of 13 TeV13\,\rm{TeV}, corresponding to an integrated luminosity of 6 fb−16\,\rm{fb}^{-1}. By considering the Λb0→Λc+D‟0K−\Lambda_b^0 \rightarrow \Lambda_c^{+} \overline{D}^0 K^{-} decay as reference channel, the following branching fraction ratios are measured to be, B(Λb0→Σc++D−K−)B(Λb0→Λc+D‟0K−)=0.282±0.016±0.016±0.005,B(Λb0→Σc∗++D−K−)B(Λb0→Σc++D−K−)=0.460±0.052±0.028,B(Λb0→Σc++D∗−K−)B(Λb0→Σc++D−K−)=2.261±0.202±0.129±0.046,B(Λb0→Σc∗++D∗−K−)B(Λb0→Σc++D−K−)=0.896±0.137±0.066±0.018,\frac{\cal{B} (\Lambda_{b}^{0} \rightarrow \Sigma_{c}^{++} \rm{D}^{-} {K}^{-})}{\cal{B}(\Lambda_{b}^{0} \rightarrow \Lambda_c^{+} \rm \overline{D}^0 {K}^{-})} = {0.282}\pm{0.016}\pm{0.016}\pm{0.005}, \frac{\cal{B}(\Lambda_{b}^{0} \rightarrow \Sigma_{c}^{*++} \rm {D}^{-} {K}^{-})}{\cal{B}(\Lambda_{b}^{0} \rightarrow \Sigma_c^{++} \rm {D}^{-} {K}^{-})} = {0.460}\pm{0.052}\pm{0.028}, \frac{\cal{B}(\Lambda_{b}^{0} \rightarrow \Sigma_{c}^{++} \rm {D}^{*-} {K}^{-})}{\cal{B}(\Lambda_{b}^{0} \rightarrow \Sigma_c^{++} \rm {D}^{-} {K}^{-})} = {2.261}\pm{0.202}\pm{0.129}\pm{0.046}, \frac{\cal{B}(\Lambda_{b}^{0} \rightarrow \Sigma_{c}^{*++} \rm D^{*-} K^{-})}{\cal{B}(\Lambda_{b}^{0} \rightarrow \Sigma_c^{++} \rm D^{-} K^{-})} = {0.896}\pm{0.137}\pm{0.066}\pm{0.018}, where the first uncertainties are statistical, the second are systematic, and the third are due to uncertainties in the branching fractions of intermediate particle decays. These initial observations mark the beginning of pentaquark searches in these modes, with more data set to become available following the LHCb upgrade

    Observation of the Bc+→J/ψπ+π0B_c^+ \to J/\psi \pi^+ \pi^0 decay

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    International audienceThe first observation of the Bc+→J/ψπ+π0B_c^+ \to J/\psi \pi^+ \pi^0 decay is reported with high significance using proton-proton collision data, corresponding to an integrated luminosity of 9fb−1^{-1}, collected with the LHCb detector at centre-of-mass energies of 7, 8, and 13 TeV. The ratio of its branching fraction relative to the Bc+→J/ψπ+B_c^+ \to J/\psi \pi^+ channel is measured to be B(Bc+→J/ψπ+π0)B(Bc+→J/ψπ+)=2.80±0.15±0.11±0.16 , \frac{ {\cal{B}}( B_c^+ \to J/\psi \pi^+\pi^0 ) } { {\cal{B}}( B_c^+ \to J/\psi \pi^+ ) } = 2.80 \pm 0.15 \pm 0.11 \pm 0.16 \,, where the first uncertainty is statistical, the second systematic and the third related to imprecise knowledge of the branching fractions for B+→J/ψK∗+B^+ \to J/\psi K^{*+} and B+→J/ψK+B^+ \to J/\psi K^+ decays, which are used to determine the π0\pi^0 detection efficiency. The π+π0\pi^+\pi^0 mass spectrum is found to be consistent with the dominance of an intermediate ρ+\rho^+ contribution in accordance with a model based on QCD factorisation

    Tracking of charged particles with nanosecond lifetimes at LHCb

    No full text
    International audienceA method is presented to reconstruct charged particles with lifetimes between 10 ps and 10 ns, which considers a combination of their decay products and the partial tracks created by the initial charged particle. Using the Ξ−\Xi^- baryon as a benchmark, the method is demonstrated with simulated events and proton-proton collision data at s=13\sqrt{s}=13 TeV, corresponding to an integrated luminosity of 2.0 fb−1{}^{-1} collected with the LHCb detector in 2018. Significant improvements in the angular resolution and the signal purity are obtained. The method is implemented as part of the LHCb Run 3 event trigger in a set of requirements to select detached hyperons. This is the first demonstration of the applicability of this approach at the LHC, and the first to show its scaling with instantaneous luminosity

    Observation of new charmonium(-like) states in B+→D∗±D∓K+B^+ \to D^{*\pm} D^{\mp} K^+ decays

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    A study of resonant structures in B+→D∗+D−K+B^{+}\rightarrow{D^{*+}D^{-}K^{+}} and B+→D∗−D+K+B^{+}\rightarrow{D^{*-}D^{+}K^{+}} decays is performed, using proton-proton collision data at centre-of-mass energies of s=7,8\sqrt{s}=7, 8, and 1313TeV recorded by the LHCb experiment, corresponding to an integrated luminosity of 9 fb−1{}^{-1}. A simultaneous amplitude fit is performed to the two channels with contributions from resonances decaying to D∗−D+D^{*-}D^{+} and D∗+D−D^{*+}D^{-} states linked by CC-parity. This procedure allows the CC-parities of resonances in the D∗±D∓D^{*\pm}D^{\mp} mass spectra to be determined. Four charmonium(-like) states are observed decaying into D∗±D∓D^{*\pm}D^{\mp}: ηc(3945)\eta_c(3945), hc(4000)h_c(4000), χc1(4010)\chi_{c1}(4010) and hc(4300)h_c(4300), with quantum numbers JPCJ^{PC} equal to 0−+0^{-+}, 1+−1^{+-}, 1++1^{++} and 1+−1^{+-}, respectively. At least three of these states have not been observed previously. In addition, the existence of the Tcˉsˉ0∗(2870)0T_{\bar{c}\bar{s}0}^{*}(2870)^{0} and Tcˉsˉ1∗(2900)0T_{\bar{c}\bar{s}1}^{*}(2900)^{0} resonances in the D−K+D^{-}K^{+} mass spectrum, already observed in the B+→D+D−K+B^{+} \rightarrow D^{+} D^{-} K^{+} decay, is confirmed in a different production channel.A study of resonant structures in B+→D∗+D−K+B^{+}\rightarrow{D^{\ast+}D^{-}K^{+}} and B+→D∗−D+K+B^{+}\rightarrow{D^{\ast-}D^{+}K^{+}} decays is performed, using proton-proton collision data at centre-of-mass energies of s=7,8\sqrt{s}=7, 8, and 1313 TeV recorded by the LHCb experiment, corresponding to an integrated luminosity of 9 fb−1^{-1}. A simultaneous amplitude fit is performed to the two channels with contributions from resonances decaying to D∗−D+D^{\ast-}D^{+} and D∗+D−D^{\ast+}D^{-} states linked by CC parity. This procedure allows the CC-parities of resonances in the D∗±D∓D^{\ast\pm}D^{\mp} mass spectra to be determined. Four charmonium(-like) states are observed decaying into D∗±D∓D^{\ast\pm}D^{\mp}: ηc(3945)\eta_c(3945), hc(4000)h_c(4000), χc1(4010)\chi_{c1}(4010) and hc(4300)h_c(4300), with quantum numbers JPCJ^{PC} equal to 0−+0^{-+}, 1+−1^{+-}, 1++1^{++} and 1+−1^{+-}, respectively. At least three of these states have not been observed previously. In addition, the existence of the Tcˉsˉ0∗(2870)0T_{\bar{c}\bar{s}0}^{*}(2870)^{0} and Tcˉsˉ1∗(2900)0T_{\bar{c}\bar{s}1}^{*}(2900)^{0} resonances in the D−K+D^-K^+ mass spectrum, already observed in the B+→D+D−K+B^+ \to D^+ D^- K^+ decay, is confirmed in a different production channel
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