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}.

Thoracic endovascular aortic repair for acute aortic dissection complicated by mesenteric malperfusion: an evaluation by computational fluid dynamics

Computational fluid dynamics was performed to simulate haemodynamics of type B aortic dissection complicated by mesenteric malperfusion caused by dynamic obstruction in a 70-year-old man. Streamline analysis showed disappearance of antegrade flow in the false lumen of the descending aorta and attenuation of intermittent flap-induced disruption of visceral vessel perfusion after entry coverage. Quantitative analysis showed endovascular repair increased perfusion volume of the coeliac artery and superior mesenteric artery by 55.6% and 77.4%, respectively. Entry closure with thoracic endovascular prosthesis improved mesenteric malperfusion by attenuating the intermittent flap-induced perfusion disruption.

The effect of balloon-expandable stent and self-expanding stent on changes in mitral annular motion after aortic valve replacement in patients with aortic stenosis

OBJECTIVES

The purpose of this study was to evaluate the effect of decalcification and existence of stent at the aortic annulus on mitral annular motion after surgery.

METHODS

Patients receiving Inspiris (Edwards, CA, USA, n = 117), Intuity (Edwards, n = 36), Perceval (Corcym, London, UK, n = 36), Evolut (Medtronics, MN, USA, n = 81) and Sapien 3 (Edwards, n = 250) were included in the study. Mitral annular motion was evaluated by E', using tissue doppler imaging.

RESULTS

After surgery, a significant increase in E' was observed in patients receiving Inspiris (Before: 4.2 ± 1.21 cm/s vs. Discharge: 5.0 ± 1.23 cm/s, p < 0.001). Mid-term echocardiogram performed at 11.8 ± 2.2 months after the surgery, showed a significant increase in E' in patients receiving Inspiris (Before: 4.2 ± 1.21 cm/s vs. Mid-term: 5.2 ± 1.20 cm/s, p < 0.001) and Perceval (Before: 3.9 ± 1.34 cm/s vs. Mid-term: 4.5 ± 1.24 cm/s, p = 0.008). Univariable analysis showed a higher increase in E' in patients with decalcified annulus compared to those without decalcified annulus (Decalcification: 0.15 ± 1.321 cm/s vs. No Decalcification: 0.66 ± 1.420 cm/s, p < 0.001). Multivariable analysis showed that balloon-expandable stent (β = - 0.6960, p < 0.001) and self-expanding stent (r = - 0.3592, p = 0.042) were independent limiting factors for an increase in E' at discharge. However, balloon-expandable stent (β = - 0.8382, p < 0.001), and not self-expanding stent (β = - 0.3682, p = 0.089), was a remaining independent factor associated with E' at mid-term follow-up.

CONCLUSIONS

Decalcification was associated with improvement in E' after surgery. Balloon-expandable stent was an independent limiting factor for improvement in E' up to 1 year after the surgery, while self-expanding stent was not a significant factor after 1 year.

Left ventricular remodeling and long-term outcomes of aortic stenosis patients receiving 19 mm Mosaic

Mosaic valve shows higher pressure gradient after aortic valve replacement compared to other same size labeled prostheses in postoperative echocardiogram. The purpose of this study was to evaluate the mid-term echocardiogram findings and long-term clinical outcomes of patients receiving a 19 mm Mosaic. Forty-six aortic stenosis patients receiving 19 mm Mosaic and 112 patients receiving either 19 mm Magna or Inspiris, who underwent mid-term follow-up echocardiogram were included in the study. Mid-term hemodynamic measurements evaluated by trans-thoracic echocardiogram and long-term outcomes were compared. Patients receiving Mosaic were significantly older (Mosaic: 76 ± 5.1 years vs. Magna/Inspiris: 74 ± 5.5 years, p = 0.046) and had smaller body surface area (Mosaic: 1.40 ± 0.114m2 vs. Magna/Inspiris: 1.48 ± 0.143m2, p < 0.001). There were no significant differences in comorbidities and medications. Post-operative echocardiogram performed at 1 week after the surgery showed higher maximum pressure gradient in patients receiving Mosaic (Mosaic: 38 ± 13.5 mmHg vs. Magna/Inspiris: 31 ± 10.7 mmHg, p = 0.002). Furthermore, mid-term echocardiogram follow-up performed at median duration of 53 ± 14.9 months after the surgery continuously showed higher maximum pressure gradient in patients receiving Mosaic (Mosaic: 45 ± 15.6 mmHg vs. Magna/Inspiris: 32 ± 13.0 mmHg, p < 0.001). However, there were no significant difference in changes in left ventricular mass from baseline in both groups. Kaplan-Meyer curve also showed no difference in long-term mortality and major adverse cardiac and cerebrovascular event between the two groups. Although the pressure gradient across the valve evaluated by echocardiogram was higher in 19 mm Mosaic compared to 19 mm Magna/Inspiris, there were no significant differences in left ventricular remodeling and long-term outcomes between the two groups.

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.

Appropriate sizing of the frozen elephant trunk: How to predict proximal descending aortic diameter prior to dissection?

OBJECTIVE

The predissection aortic diameter is the best reference for determining the size of the frozen elephant trunk in aortic dissection. We aimed to develop a new prediction method to estimate the predissection diameter of proximal descending aorta. Furthermore, we evaluated the accuracy of the estimated predissection proximal descending aortic diameters calculated using 3 prediction methods.

METHODS

A total of 39 patients with acute type A aortic dissection who underwent predissection computed tomography were included in derivation sets. We measured the aortic dimensions at 3 levels of the proximal descending aorta: 5, 10, and 15 cm from zone 2. We developed a new prediction method-postdissection aortic diameter divided by 1.13 (AoDNew factor)-and estimated the predissection aortic diameter using the new and previously proposed methods by Rylski (AoDRylski) and Yamauchi (EquationYamauchi). Furthermore, we validated the new prediction method using a validation dataset with 24 patients.

RESULTS

The rate of bias ≤2 mm was significantly greater with EquationYamauchi and AoDNew factor than with AoDRylski in the derivation group at each level of the proximal descending aorta (P < .001). In the validation group, the rate of bias ≤2 mm was significantly greater with EquationYamauchi and AoDNew factor than with AoDRylski at 10 cm and 15 cm from zone 2 (10 cm: P = .014, 15 cm: P < .001).

CONCLUSIONS

These results suggest that the new prediction method can be used as a simple and accurate estimation method for the predissection aortic diameter at the proximal descending aorta.

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.

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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[Non-A Non-B Aortic Dissection Complicated with Right Aortic Arch Treated by Extended Thoracic Aortic Repair]

A 44-year old man with a history of Stanford type B acute aortic dissection was admitted for the treatment of acute aortic dissection. Computed tomography( CT) scan showed a descending entry-type non-A non-B aortic dissection with a maximum diameter of 65 mm occurring in a patient with Edwards typeⅢ right aortic arch whose left subclavian artery was obliterated. The patient was initially treated conservatively and underwent one-stage extended aortic repair from the ascending aorta to the descending thoracic aorta via median sternotomy 22 days after the symptom onset. Although the patient suffered from right empyema postoperatively, he was discharged from the hospital on postoperative day 64 after 4 weeks antibiotics therapy. The patient was also complicated by right recurrent nerve palsy, hoarseness improved over the 8 months after surgery.

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.

Association between Plasma Ascorbic Acid Levels and Postoperative Delirium in Older Patients Undergoing Cardiovascular Surgery: A Prospective Observational Study

BACKGROUND

The incidence of delirium is high in older patients undergoing cardiovascular surgery with cardiopulmonary bypass (CPB). Intraoperative tissue hypoperfusion and re-reperfusion injury, which generate reactive oxygen species (ROS), are suggested to induce delirium. Ascorbic acid is an excellent antioxidant and may reduce organ damage by inhibiting the production of ROS. This prospective observational study aimed to measure pre- and postoperative plasma ascorbic acid levels and examine their association with delirium.

METHODS

Patients older than 70 years of age scheduled for elective cardiovascular surgery using CPB were enrolled. From September 2020 to December 2021, we enrolled 100 patients, and the data of 98 patients were analyzed.

RESULTS

In total, 31 patients developed delirium, while 67 did not. Preoperative plasma ascorbic acid levels did not differ between the non-delirium and delirium groups (6.0 ± 2.2 vs. 5.5 ± 2.4 µg/mL, p = 0.3). Postoperative plasma ascorbic acid levels were significantly different between the groups (2.8 [2.3-3.5] vs. 2.3 [1.6-3.3] µg/mL, p = 0.037).

CONCLUSIONS

In patients who undergo cardiovascular surgery with CPB, lower postoperative plasma ascorbic acid levels may be associated with the development of delirium.

Association between frailty and long-term outcomes among patients undergoing thoracic aortic surgery via median sternotomy

OBJECTIVE

Preoperative assessment of frailty is important for predicting postoperative outcomes. This study investigated the association between frailty and late outcomes among patients who underwent thoracic aortic surgery via median sternotomy.

METHODS

A total of 1010 patients underwent thoracic aortic surgery via median sternotomy between April 2008 and December 2016. Patients < 65 years of age, those who underwent urgent or emergent surgery, and those with incomplete data were excluded; as such, 374 patients were ultimately included in the present study. Frailty was evaluated using an index comprising history of dementia, body mass index < 18.5 kg/m², and hypoalbuminemia. A frailty score from 0 to 3 was determined by assigning 1 point for each criterion met. Frailty was defined as a score ≥ 1. Patients were categorized into of 2 groups: frail (n = 52) and non-frail (n = 322). The mean follow-up was 6.1 ± 3.1 years.

RESULTS

Overall in-hospital mortality did not differ between the frail and non-frail groups. However, the incidence of re-exploration for bleeding and discharge to a health care facility was higher in the frail group than in the non-frail group. Multivariable analysis revealed that preoperative frailty was an independent predictor of late mortality during follow-up [hazard ratio 3.71 (95% confidence interval 2.16-6.37); P < 0.001].

CONCLUSION

Preoperative frailty was associated with late mortality after thoracic aortic surgery. Assessment of preoperative frailty using a simple frailty index may be useful in the decision-making process for elderly patients.

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.

The effect of stent and decalcification on mitral annular motion after aortic valve replacement

OBJECTIVE

The purpose of this study was to evaluate the changes in mitral annular motion after surgery in patients with aortic stenosis.

METHODS

Patients receiving Edwards (Edwards) valves were included in the study. Echocardiographic findings were compared among the three treatments postoperatively, at discharge, and at 1 year after the surgery. Mitral annular motion was evaluated by e prime, using tissue doppler imaging.

RESULTS

There were 111 patients receiving Inspiris, 30 patients receiving Intuity and 241 patients receiving Sapien 3. The patients receiving Sapien 3 were significantly older, (Inspiris: 71 ± 6.7 years vs. Intuity: 75 ± 5.2 years vs. Sapien 3: 84 ± 5.1 years, p < .001), and prevalence of hemodialysis were significantly higher in patients receiving Intuity (Inspiris: 11.7% vs. Intuity: 46.7% vs. Sapien 3: 0.0%, p < .001). There was a significant improvement in mean pressure gradient in all groups (Inspiris: 55 ± 21.2-13 ± 5.2 mmHg, p < .001; Intuity: 48 ± 17.6-12 ± 4.9 mmHg, p < .001, Sapien 3: 55 ± 16.6-14 ± 5.2 mmHg, p < .001). Decalcification was associated with increase in e prime after surgery (no decalcification: 0.10 ± 1.280 cm/s vs. decalcification: 0.68 ± 1.405 cm/s, p < .001) Further, existence of stent was associated with less increase in e prime after surgery (no stent: 0.83 ± 1.210 cm/s vs. stent: 0.10 ± 1.356; p < .001). Multivariate analysis showed that existence of stent but not decalcification of the aortic valve was independently associated with changes in e prime after surgery (β: -.4679, 95% confidence interval: -0.93389 to -0.00200, p = .049).

CONCLUSIONS

Although improvement in pressure gradient was achieved in all treatments, existence of stent inhibited mitral annular motion after surgery.

Effect of nadir hematocrit during cardiopulmonary bypass on the early outcomes after surgical repair of acute type A aortic dissection

OBJECTIVE

Although hemodilution during hypothermic cardiopulmonary bypass (CPB) had been thought to improve microcirculation and reduce blood viscosity, there has been no report investigating the effect of low nadir hematocrit (Hct) values caused by severe hemodilution on the surgical outcomes of patients with acute type A aortic dissection (ATAAD).

METHODS

We retrospectively reviewed 112 consecutive patients who emergently underwent emergency surgical repair of ATAAD at our institution. The patients were classified into the high Hct (nadir Hct ≥ 21% during CPB; n = 51) and low Hct (nadir Hct < 21% during CPB; n = 61) groups. After propensity score matching of preoperative characteristics, surgical outcomes were compared between the groups.

RESULTS

Although there was no difference in the surgical procedure, longer CPB time and more blood transfusion during surgery were needed in the low Hct group than in the high Hct group. After surgery, estimated glomerular filtration rate was significantly lower (p = .015), lactaic acid was higher (p = .045), and intubation time was longer (p = .018) in the low Hct group than in the high Hct group, although there was no difference in hospital mortality between the groups. The AUC of the nadir Hct during CPB as a prognostic indicator of prolonged postoperative ventilator support was 0.8, with the highest accuracy at 16.7% (sensitivity 88%, specificity 76.9%). In all cohorts, female sex was an independent risk factor for a lower nadir Hct value of <21% during CPB.

CONCLUSION

A lower nadir Hct value of <21% during CPB may be associated with postoperative renal dysfunction and prolonged ventilator support in patients with ATAAD.

A Compressed Collagen Construct for Studying Endothelial-Smooth Muscle Cell Interaction Under High Shear Stress

The coculture of vascular endothelial cells (ECs) on collagen gels containing smooth muscle cells (SMCs) has been carried out to investigate cellular interactions associated with blood vessel pathophysiology under wall shear stress (WSS) conditions. However, due to a lack of gel stiffness, the previous collagen gel coculture constructs are difficult to use for pathologic higher WSS conditions. Here, we newly constructed a coculture model with centrifugally compressed cell-collagen combined construct (C6), which withstands higher WSS conditions. The elastic modulus of C6 was approximately 6 times higher than that of the uncompressed collagen construct. The level of α-smooth muscle actin, a contractile SMC phenotype marker observed in healthy arteries, was elevated in C6 compared with that of the uncompressed construct, and further increased by exposure to a physiological level WSS of 2 Pa, but not by a pathological level of 20 Pa. WSS conditions of 2 and 20 Pa also induced different expression ratios of matrix metalloproteinases and their inhibitors in the C6 coculture model but did not in monocultured ECs and SMCs. The C6 coculture model will be a powerful tool to investigate interactions between ECs and SMCs under pathologically high WSS conditions.

High-precision measurement of the W boson mass with the CDF II detector

The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass, M_W, using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 tera-electron volt center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider. A sample of approximately 4 million W boson candidates is used to obtain [Formula: see text], the precision of which exceeds that of all previous measurements combined (stat, statistical uncertainty; syst, systematic uncertainty; MeV, mega-electron volts; c, speed of light in a vacuum). This measurement is in significant tension with the standard model expectation.

Aortic Agatston score correlates with the progression of acute type A aortic dissection

Aortic calcification in the tunica media is correlated with aortic stiffness, elastin degradation, and wall shear stress. The study aim was to determine if aortic calcifications influence disease progression in patients with acute type A aortic dissection (ATAAD). We retrospectively reviewed a total of 103 consecutive patients who had undergone surgery for ATAAD at our institution between January 2009 and December 2019. Of these, 85 patients who had preoperatively undergone plain computed tomography angiography (CTA) for evaluation of their aortic calcification were included. Moreover, we assessed the progression of aortic dissection after surgery via postoperative CTA. Using a classification and regression tree to identify aortic Agatston score thresholds predictive of disease progression, the patients were classified into high-score (Agatston score ≥ 3344; n  =   36) and low-score (<3344; n  =   49) groups. Correlations between aortic Agatston scores and CTA variables were assessed. Higher aortic Agatston scores were significantly correlated with the smaller distal extent of aortic dissection (p < 0.001), larger true lumen areas of the ascending (p  =  0.009) and descending aorta (p =   0.002), and smaller false lumen areas of the descending aorta (p =  0.028). Patients in the high-score group were more likely to have DeBakey type II dissection (p =  0.001) and false lumen thrombosis (p  =  0.027) than those in the low-score group, thereby confirming the correlations. Aortic dissection in the high-score group was significantly less distally extended (p < 0.001). A higher aortic Agatston score correlates with the larger true lumen area of the ascending and descending aorta and the less distal progression of aortic dissection in patients with ATAAD. Interestingly, the findings before and after surgery were consistent. Hence, aortic Agatston scores are associated with aortic dissection progression and may help predict postoperative residual dissected aorta remodeling.

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.

Influence of residual primary entry following the tear-oriented strategy for acute type A aortic dissection

OBJECTIVES

Although a tear-oriented strategy has contributed to improving short-term surgical outcomes of acute type A aortic dissection (ATAAD), long-term clinical influences of residual entry tear in the downstream aorta have not been fully investigated. The goal of this study was to assess the long-term surgical outcomes of ATAAD with or without a residual entry tear in the downstream aorta.

METHODS

Medical records of 1107 patients with ATAAD who underwent emergency surgery between 1990 and 2018 were retrospectively reviewed. A tear-oriented paradigm was adopted for the baseline strategy. The 837 patients in whom the entry tears were resected comprised the resected group, and the 270 patients with a residual entry tear comprised the residual group. Of these patients, 252 in each group were analysed using propensity score matching, and long-term outcomes were compared with or without residual entry.

RESULTS

Hospital deaths were lower in the resected group (3.2% vs 8.3%; P = 0.020). The survival rate was not significantly different between the groups: It was 83.8% and 68.5% in the resected group and 80.2% and 66.5% in the residual group at 5 and 10 years, respectively (P = 0.600). However, residual entry in the downstream aorta affected the distal aortic event-free survival rate (90.4% and 80.6% in the resected group and 82.3% and 67.4% in the residual group at 5 and 10 years, respectively; P = 0.003). Furthermore, multivariable risk analysis of 1107 patients confirmed that a residual entry in the downstream aorta was a risk factor for distal aortic events.

CONCLUSIONS

The tear-oriented strategy remains the gold standard for high-risk patients; however, the extensive operation might be considered for stable patients to reduce long-term aortic events.

Treatment Site Does Not Affect Changes in Pulse Wave Velocity but Treatment Length and Device Selection Are Associated With Increased Pulse Wave Velocity After Thoracic Endovascular Aortic Repair

Background: Endovascular treatment of aortic aneurysm is associated with an increase in pulse wave velocity (PWV) after surgery. However, the effect of different types of endovascular devices on PWV at different sites of the thoracic aorta remains unclear.

Objectives: The purposes of this study were (1) to investigate the changes in PWV after endovascular treatment of thoracic aortic aneurysm; (2) to evaluate whether there is a difference in the changes in PWV at different treatment sites; and (3) to evaluate the effect of treatment length on changes in PWV.

Methods: From July 2008 to July 2021, 276 patients underwent endovascular treatment of the true thoracic aortic aneurysm. Of these patients, 183 patients who underwent preoperative and postoperative PWV measurement within 1 year of surgery were included in the study. The treatment length index was calculated by treatment length divided by the height of the patients.

Results: Five different types of endovascular devices were used (Najuta, Kawasumi Laboratories, Inc., Tokyo, Japan; TAG, W.L. Gore & Associates, Inc., AZ, USA; Relay, Bolton Medical, Inc., FL, USA; Talent/Valiant, Medtronic, MN, USA; and Zenith, Cook Medical, IN, USA). There was no significant change in PWV in patients receiving Najuta (Before: 2,040 ± 346.8 cm/s vs. After: 2,084 ± 390.5 cm/s, p = 0.14). However, a significant increase was observed in other devices: TAG (Before: 2,090 ± 485.9 cm/s vs. After: 2,300 ± 512.1 cm/s, p = 0.025), Relay (Before: 2,102 ± 465.3 cm/s vs. After: 2,206 ± 444.4 cm/s, p = 0.004), Valiant (Before: 1,696 ± 330.2 cm/s vs. After: 2,186 ± 378.7 cm/s, p < 0.001), and Zenith (Before: 2,084 ± 431.7 cm/s vs. After: 2,321 ± 500.6 cm/s, p < 0.001). There was a significant increase in PWV in patients treated from aortic arch (Before: 2,006 ± 333.7 cm/s vs. After: 2,132 ± 423.7 cm/s, p < 0.001) and patients treated from descending thoracic aorta (Before: 2,116 ± 460.9 cm/s vs. After: 2,292 ± 460.9 cm/s, p < 0.001). Multivariate analysis showed that treatment site was not an independent factor associated with changes in PWV. However, Najuta (Coef −219.43, 95% CI −322.684 to −116.176, p < 0.001) and treatment index (Coef 147.57, 95% CI 24.826 to 270.312, p = 0.019) were independent factors associated with changes in PWV.

Conclusion: Najuta did not show a significant increase in PWV, while other commercially available devices showed a significant increase. The treatment site did not have a different effect on PWV. However, the treatment length was an independent factor associated with an increase in PWV.

Evaluation of oversizing in association with conduction disorder after implantation of a rapid deployment valve

Rapid deployment valve has expanded surgical indication for high-risk patients with aortic stenosis despite its accommodated risk for conduction disorder (CD). The purpose of this study was to evaluate the degree of oversizing in association with postoperative CD. During June 2019 to September 2021, 25 patients underwent aortic valve replacement with Edwards INTUITY. Device size selection was evaluated intraoperatively using provided sizers. Oversizing was evaluated retrospectively by measuring the difference of the dimension of the annulus and left ventricular outflow tract (LVOT) compared to the dimensions of the device used by preoperative-computed tomography. Although there was no incidence of pacemaker implantation, seven patients (28.0%) experienced CD after surgery. There was no difference in device area and annulus area (CD: - 37 ± 22.7 mm² vs. no CD: - 56 ± 63.6 mm², p = 0.47), and device circumference and annulus circumference (CD: - 4.4 ± 2.77 mm vs. no CD: - 6.9 ± 5.60 mm, p = 0.26) in patients with and without CD. However, there was a significant difference in area of the device skirt and sub-annular area at the LVOT (CD: 114 ± 28.4 mm² vs. no CD: - 8 ± 80.0 mm², p < 0.001), and circumference of device skirt and the LVOT (CD: 3.9 ± 2.08 mm vs. no CD: - 4.6 ± 5.24 mm, p < 0.001) between the two groups. Receiver operating characteristic curve analysis showed that an area difference of 77.7 mm² and circumference difference of 0.91 mm at LVOT were associated with postoperative CD with specificities of 0.83, 0.78 and sensitivity of 1.0, 1.0, respectively. Preoperative measurement of the LVOT may be useful in evaluating the risk of postoperative CD in patients receiving rapid deployment valve.

An increased prothrombin time-international normalized ratio in patients with acute type A aortic dissection: contributing factors and their influence on outcomes

PURPOSE

We investigated factors contributing to coagulopathy in patients with acute type A aortic dissection (ATAAD) and coagulopathy's influence on patient outcomes.

METHODS

We grouped 420 patients who underwent ATAAD repair-none under anticoagulation therapy or with liver disease-by the prothrombin time-international normalized ratio (PT-INR) at admission:  <  1.2 (no coagulopathy, n  =  371), 1.2-1.49 (mild coagulopathy, n  =  33), or  ≥  1.5 (severe coagulopathy, n  =  16). We then compared the clinical presentation, dissection morphology, and outcomes among the groups. We assessed the PT-INR in relation to the preoperative hemodynamics and searched for factors predictive of a PT-INR  ≥  1.2.

RESULTS

The transfusion volume and operation time were increased among patients with coagulopathy (P  <  0.05). The in-hospital mortality (15.2-37.5% vs. 5.1%, P  < 0.001) and 5-year survival (61.1-74.4% vs. 87.6%) were relatively poor for these patients. The median PT-INR was 1.03 (0.97-1.1) for patients with stable hemodynamics (n  =  318), 1.11 (1.02-1.21) for those in shock (blood pressure  <  80 mmHg) not given cardiopulmonary resuscitation (CPR) (n  =  81), and 1.1 (1.0-1.54) for those in shock given CPR (n  =  21) (P  < 0.001). A multivariable analysis identified shock (P  <  0.001), a partially thrombosed false lumen (P  =  0.006), and mesenteric malperfusion (P  =  0.016) as predictive variables.

CONCLUSIONS

Shock, a partially thrombosed false lumen, and mesenteric malperfusion appear to be predictive of dissection-related coagulopathy, which influences outcomes negatively.

Impact of prosthesis-patient mismatch on late outcomes after bioprosthetic mitral valve replacement for mitral regurgitation

Negative impact of prosthesis-patient mismatch on long-term survival after valve replacement has been reported. However, the effect of prosthesis-patient mismatch after bioprosthetic mitral valve replacement has not yet been well examined. The purpose of this study was to investigate the effect of prosthesis-patient mismatch on late outcomes after bioprosthetic mitral valve replacement for mitral regurgitation. A total of 181 patients underwent bioprosthetic mitral valve replacement between April 2008 and December 2016. After excluding patients with mitral stenosis and those with incomplete data, 128 patients were included in the study. Postoperative transthoracic echocardiography was performed before discharge for all patients and the effective orifice area of bioprosthetic mitral valve was calculated using the formula: 220/pressure half-time, and the effective orifice area index was calculated by the formula: effective orifice area/body surface area. Prosthesis-patient mismatch was defined as a postoperative effective orifice area index ≤ 1.2 cm²/m². The characteristics and outcomes were compared between the groups. There were 34 patients (26.6%) with prosthesis-patient mismatch and 94 patients (73.4%) without prosthesis-patient mismatch. There were no significant differences in the in-hospital mortality and morbidities. Multivariable analysis showed that prosthesis-patient mismatch was an independent predictor of late mortality (hazard ratio 3.38; 95% confidence interval 1.69-6.75; p = 0.001) and death from heart failure (hazard ratio 31.03, 95% confidence interval 4.49-214.40, p < 0.001). Prosthesis-patient mismatch at discharge after mitral valve replacement for mitral regurgitation was associated with long-term mortality and death from heart failure.

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.

Long-term outcomes after aortic valve replacement using a 19-mm bioprosthesis

OBJECTIVES

Transcatheter aortic valve replacement is known to be associated with improved haemodynamics in patients with aortic stenosis and a small aortic annulus. However, limited benchmark data are available regarding the long-term outcomes in patients treated with surgical aortic valve replacement (SAVR). We investigated the long-term outcomes of SAVR using a 19-mm bioprosthesis.

METHODS

This study included consecutive patients who underwent SAVR using a 19-mm bioprosthesis at our hospital between 2008 and 2012.

RESULTS

In a total of 132 patients, moderate and severe prosthesis-patient mismatch occurred in 36 (27.3%) and 7 patients (5.3%), respectively. The median follow-up period was 7.7 years. The overall 5- and 10-year survival rates were 79.4% and 52.9%, respectively. The 5- and 10-year freedom from major adverse valve-related events rates were 89.6% and 74.2%, respectively. Neither moderate nor severe prosthesis-patient mismatch was associated with late mortality, major adverse valve-related events or heart failure. Follow-up echocardiographic data were obtained at a median interval of 4.8 years in 80% of patients who survived ≥6 months postoperatively. Follow-up echocardiographic data showed a significantly increased left ventricular ejection fraction, decreased mean transvalvular/transprosthetic pressure gradients and a decreased mean left ventricular mass. At follow-up, we observed moderate or severe haemodynamic structural valve deterioration in 17 patients; however, structural valve deterioration did not affect late survival or freedom from major adverse valve-related events rates, or heart failure.

CONCLUSIONS

SAVR using the 19-mm bioprosthesis was associated with satisfactory long-term clinical and haemodynamic outcomes.

Early cardiac contractility outcome of reoperative coronary artery bypass grafting using right gastroepiploic artery

BACKGROUND AND AIM OF THE STUDY

Reoperative coronary artery bypass grafting (redo CABG) still carries higher mortality and increased morbidity compared with primary CABG. In this study, we retrospectively reviewed our operative outcome of redo CABG to evaluate the impact of the left anterolateral thoracotomy approach using the right gastroepiploic artery (RGEA).

METHODS

Between 1994 and 2020, 11 patients (mean age 60.3 ± 13.1 years; nine men, two women) underwent isolated redo CABG using the RGEA via the left anterolateral thoracotomy.

RESULTS

The mean duration from the initial CABG was 128.3 ± 88.4 months. Redo CABG was performed because of graft occlusion in six patients (54.5%), graft stenosis in one patient (9.1%), and progressive disease of previously ungrafted vessels in four patients (36.4%). The total number of bypasses using RGEA (including Y-composite vein grafts) was 16 (four left anterior descending branches, two diagonal branches, five circumflex branches, five right coronary arteries). No residual graft injury, major comorbidity, or in-hospital death was observed. Changes in echocardiographic values before and after redo CABG were 210.9 ± 48.2 ml and 175.0 ± 41.4 ml in left ventricular end-diastolic volume, 130.2 ± 49.2 ml and 94.4 ± 33.0 ml in left ventricular end-systolic volume, and 45.6 ± 11.0% and 52.2 ± 10.7% in left ventricular ejection fraction, respectively. These parameters significantly improved after redo CABG.

CONCLUSIONS

Redo CABG with RGEA grafting via the left anterolateral thoracotomy approach is a safe and effective surgical procedure especially in improving cardiac contractility in patients who required revascularization.

[Rapid Growing Thoracic Aortic Aneurysm in a Patient with Relapsing Polychondritis]

A 26-year-old man with relapsing polychondritis was admitted for the treatment of multiple thoracic aortic aneurysms in the ascending and descending aorta. Descending thoracic aortic aneurysm showed rapid expansion, therefore, the patient underwent an extended thoracic aortic repair from the ascending aorta to the descending aorta via anterolateral thoracotomy and partial sternotomy. Although postoperative course was uneventful, aortic root enlargement and severe aortic insufficiency progressed over the next two years. He and his family refused redo surgical intervention and the patient died of heart failure. Careful perioperative follow-up may be mandatory in a patient with relapsing polychondritis complicated by cardiovascular disease.

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.

Preoperative sarcopenia is associated with late mortality after off-pump coronary artery bypass grafting

OBJECTIVES

We investigated the association between sarcopenia (a marker of frailty) and outcomes after coronary artery bypass grafting (CABG).

METHODS

This study included 304 patients who underwent elective isolated off-pump CABG at our hospital between October 2008 and August 2013. Psoas muscle area was measured on preoperative computed tomography scans. Sarcopenia was defined as the lowest sex-specific quartile of the psoas muscle area index (the psoas muscle area normalized for height). Patients were categorized into a sarcopenia group (76 patients) and a non-sarcopenia group (228 patients). Patients in the sarcopenia group were older and showed a lower body mass index, lower serum haemoglobin and albumin levels and lower prevalence of dyslipidaemia but higher prevalence of renal dysfunction and peripheral artery disease. The mean follow-up period was 4.5 ± 2.3 years.

RESULTS

The cut-off values for sarcopenia were psoas muscle area index 215 and 142 mm2/m2 in men and women, respectively. No intergroup difference was observed in the in-hospital mortality and morbidity rates. After risk adjustment using inverse probability weighting analysis, late mortality rates were significantly higher in the sarcopenia group than in the non-sarcopenia group (P = 0.022). Multivariable analysis showed that preoperative sarcopenia was an independent predictor of late mortality (hazard ratio 4.25, 95% confidence interval 2.18-8.28; P < 0.001). Preoperative sarcopenia was not associated with major adverse cardiac and cerebrovascular events during follow-up.

CONCLUSIONS

Preoperative sarcopenia (assessed by psoas muscle area index) was associated with late mortality after CABG and effectively predicts postoperative prognosis.

Utility of double arterial cannulation for surgical repair of acute type A dissection

OBJECTIVES

Outcomes of planned and unplanned (rescue) double arterial cannulation (DAC) in surgery for acute type A aortic dissection were investigated retrospectively.

METHODS

The study involved 805 patients who were divided into 4 groups according to the cannulation strategy: single cannulation of the femoral artery (n = 338), axillary artery (n = 256), left ventricular apex (n = 52) or ascending aorta (n = 5) (total, n = 57), and DAC (n = 154). Patients who underwent DAC were divided between planned (n = 132) and rescue (n = 22) usage. Characteristics and outcomes were compared between groups. Both unmatched and propensity score-matched analyses were performed.

RESULTS

Shock (39%, 19%, 33% and 14%, in the femoral artery, axillary artery, left ventricular apex/ascending aorta and DAC, respectively) and leg malperfusion (5%, 16%, 16% and 26%, respectively) differed significantly (P < 0.001), but in-hospital mortality did not (9%, 8%, 18% and 7%, respectively; P = 0.096). The 5-year survival rates were 79.4%, 79.7%, 78.6% and 82.2%, respectively. Propensity score-matched analysis showed no statistically significant differences in in-hospital mortality rates (10%, 12%, 14% and 9%, respectively; P = 0.78) and 5-year survival rates (78.4%, 72.3%, 82.3% and 78.0%, respectively). The leading vessel combination and indications for planned and rescue DAC were the femoral and axillary arteries (98%) and true lumen narrowing and/or leg malperfusion (34%), and the axillary followed by femoral (77%) artery and low cardiopulmonary bypass flow (36%). In-hospital mortality in the planned and rescue DAC groups was 7% and 9%, respectively.

CONCLUSIONS

DAC seems effective for both prevention and management of intraoperative malperfusion.