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1.
Sci Adv ; 10(11): eadk3539, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38478600

RESUMEN

The field-induced quantum-disordered state of layered honeycomb magnet α-RuCl3 is a prime candidate for Kitaev spin liquids hosting Majorana fermions and non-Abelian anyons. Recent observations of anomalous planar thermal Hall effect demonstrate a topological edge mode, but whether it originates from Majorana fermions or bosonic magnons remains controversial. Here, we distinguish these origins from combined low-temperature measurements of high-resolution specific heat and thermal Hall conductivity with rotating magnetic fields within the honeycomb plane. A distinct closure of the low-energy bulk gap is observed for the fields in the Ru-Ru bond direction, and the gap opens rapidly when the field is tilted. Notably, this change occurs concomitantly with the sign reversal of the Hall effect. General discussions of topological bands show that this is the hallmark of an angle rotation-induced topological transition of fermions, providing conclusive evidence for the Majorana-fermion origin of the thermal Hall effect in α-RuCl3.

2.
Sci Adv ; 10(6): eadk3772, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38324692

RESUMEN

The recently discovered superconductor UTe2 is a promising candidate for spin-triplet superconductors, but the symmetry of the superconducting order parameter remains highly controversial. Here, we determine the superconducting gap structure by the thermal conductivity of ultraclean UTe2 single crystals. We find that the a-axis thermal conductivity divided by temperature κ/T in zero-temperature limit is vanishingly small for both magnetic field H‖a and H‖c axes up to H/Hc2 ∼ 0.2, demonstrating the absence of nodes around the a axis contrary to the previous belief. The present results, combined with the reduction of nuclear magnetic resonance Knight shift, indicate that the superconducting order parameter belongs to the isotropic Au representation with a fully gapped pairing state, analogous to the B phase of superfluid 3He. These findings reveal that UTe2 is likely to be a long-sought three-dimensional strong topological superconductor, hosting helical Majorana surface states on any crystal plane.

3.
Sci Adv ; 9(18): eabq5561, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37134174

RESUMEN

Continued advances in quantum technologies rely on producing nanometer-scale wires. Although several state-of-the-art nanolithographic technologies and bottom-up synthesis processes have been used to engineer these wires, critical challenges remain in growing uniform atomic-scale crystalline wires and constructing their network structures. Here, we discover a simple method to fabricate atomic-scale wires with various arrangements, including stripes, X-junctions, Y-junctions, and nanorings. Single-crystalline atomic-scale wires of a Mott insulator, whose bandgap is comparable to those of wide-gap semiconductors, are spontaneously grown on graphite substrates by pulsed-laser deposition. These wires are one unit cell thick and have an exact width of two and four unit cells (1.4 and 2.8 nm) and lengths up to a few micrometers. We show that the nonequilibrium reaction-diffusion processes may play an essential role in atomic pattern formation. Our findings offer a previously unknown perspective on the nonequilibrium self-organization phenomena on an atomic scale, paving a unique way for the quantum architecture of nano-network.

4.
J Appl Biomech ; 39(2): 90-98, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36848903

RESUMEN

This study aims to investigate the difference in hand acceleration induced by rapid changes in hand movement directions and propulsion between fast and slow groups of swimmers during front crawl swimming. Twenty-two participants, consisting of 11 fast and 11 slow swimmers, performed front crawl swimming at their maximal effort. Hand acceleration and velocity and the angle of attack were measured using a motion capture system. The dynamic pressure approach was used to estimate hand propulsion. In the insweep phase, the fast group attained significantly higher hand acceleration than the slow group in the lateral and vertical directions (15.31 [3.44] m·s-2 vs 12.23 [2.60] m·s-2 and 14.37 [1.70] m·s-2 vs 12.15 [1.21] m·s-2), and the fast group exerted significantly larger hand propulsion than the slow group (53 [5] N vs 44 [7] N). Although the fast group attained large hand acceleration and propulsion during the insweep phase, the hand velocity and the angle of attack were not significantly different in the 2 groups. The rapid change in hand movement direction could be considered in the technique of underwater arm stroke, particularly in the vertical direction, to increase hand propulsion during front crawl swimming.


Asunto(s)
Mano , Natación , Humanos , Fenómenos Biomecánicos , Extremidad Superior , Movimiento
5.
Am Heart J Plus ; 30: 100298, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38510923

RESUMEN

Background: Periodontal disease (PD) is associated with an increased risk of cardiovascular disease (CVD). Pericardial adipose tissue (PAT) is known as a marker of progressive CVD. This study sought to assess the association between PD and PAT in patients with CVD. Methods: We retrospectively investigated 135 patients admitted for CVD who underwent computed tomography coronary angiography (CTCA) and periodontal examinations. Periodontal assessment using the community periodontal index (CPI) was based on the probing pocket depth around teeth. Patients with CPI ≥3 were categorized as having PD. PAT volume was measured with a quantitative semi-automated procedure using CTCA images. Patients were divided into tertiles according to PAT volume. Baseline characteristics and PD findings were compared among the tertiles. Results: Eighty-six patients were diagnosed with PD (63.7 %). Mean PAT volume was 181.4 ml, and patients were categorized as small-PAT (PAT <148.9 ml), intermediate-PAT (148.9 ml ≤ PAT ≤204.6 ml), and large-PAT (PAT >204.6 ml). The prevalence of PD was significantly higher in large-PAT (38/46, 82.6 %) than in small-PAT (18/45, 40.0 %) and intermediate-PAT (30/44, 68.2 %) patients. Multivariate logistic regression analysis showed that body weight, history of hypertension, and the presence of PD were independent predictors for large-PAT (odds ratio [OR]: 1.12, P < 0.001, OR: 3.97, P = 0.017, and OR: 4.18, P = 0.0078, respectively). Conclusion: The presence and severity of PD were significantly correlated with PAT volume, which has been associated with progressive CVD. Further prospective studies are warranted to assess the impact of PD on the onset and outcomes of CVD.

7.
Sci Rep ; 12(1): 9187, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35654914

RESUMEN

A finite residual linear term in the thermal conductivity at zero temperature in insulating magnets indicates the presence of gapless excitations of itinerant quasiparticles, which has been observed in some candidate materials of quantum spin liquids (QSLs). In the organic triangular insulator ß'-EtMe3Sb[Pd(dmit)2]2, a QSL candidate material, the low-temperature thermal conductivity depends on the cooling process and the finite residual term is observed only in samples with large thermal conductivity. Moreover, the cooling rate dependence is largely sample dependent. Here we find that, while the low-temperature thermal conductivity significantly depends on the cooling rate, the high-temperature resistivity is almost perfectly independent of the cooling rate. These results indicate that in the samples with the finite residual term, the mean free path of the quasiparticles that carry the heat at low temperatures is governed by disorders, whose characteristic length scale of the distribution is much longer than the electron mean free path that determines the high-temperature resistivity. This explains why recent X-ray diffraction and nuclear magnetic resonance measurements show no cooling rate dependence. Naturally, these measurements are unsuitable for detecting disorders of the length scale relevant for the thermal conductivity, just as they cannot determine the residual resistivity of metals. Present results indicate that very careful experiments are needed when discussing itinerant spin excitations in ß'-EtMe3Sb[Pd(dmit)2]2.

8.
Intern Emerg Med ; 17(6): 1669-1678, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35486329

RESUMEN

INTRODUCTION: Coronary artery disease (CAD) is the most frequent cause of out-of-hospital cardiac arrest (OHCA). Nevertheless, there have been limited studies focusing on the impact of lesion complexity on resuscitated CAD patients. The purpose of the present study was to investigate the association between coronary lesion complexity and the mortality of CAD patients after OHCA. METHODS: From pooled database of two centers, which comprised 706 successfully resuscitated OHCA patients, 172 patients undergoing coronary angiography were retrospectively investigated. A total of 148 patients exhibited coronary stenosis on angiogram and were included in the final analysis. Baseline characteristics, pre-and post-hospital care, general status after resuscitation and angiographical findings were compared between the patients who deceased within 30 days and those who survived and the predictors of 30-day mortality were determined. RESULTS: Ninety-four patients (63.5%) survived at 30 days. Bystander cardiopulmonary resuscitation (CPR) (Odds ratio (OR) 0.36; 95% confidence interval (CI) 0.14-0.96; P = 0.041), revascularization of coronary stenosis (OR 0.15; 95% CI 0.19-0.86; P < 0.001), GRACE risk score (OR 1.04; 95% CI 1.02-1.05; P < 0.001) and SYNTAX score (OR 1.07; 95% CI 1.01-1.13; P = 0.025) were independent predictors of 30-day mortality. As multiple predictors such as bystander CPR, GRACE score and SYNTAX score were combined, the 30-day mortality gradually deteriorated. CONCLUSIONS: In addition to bystander CPR, GRACE score and revascularization, SYNTAX score independently predicted 30-day mortality of CAD patients after OHCA.


Asunto(s)
Reanimación Cardiopulmonar , Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Paro Cardíaco Extrahospitalario , Enfermedad de la Arteria Coronaria/complicaciones , Humanos , Paro Cardíaco Extrahospitalario/terapia , Estudios Retrospectivos
9.
Front Cardiovasc Med ; 9: 842914, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35265688

RESUMEN

Background: Near-infrared spectroscopy (NIRS) provides the localization of lipid-rich components in coronary plaques. However, morphological features in NIRS-detected lipid-rich plaques (LRP) are unclear. Methods: A total of 140 de novo culprit lesions in 140 patients with the acute coronary syndrome (ACS) who underwent NIRS and optical coherence tomography (OCT) examinations for the culprit lesions at the time of percutaneous coronary interventions were investigated. We defined a NIRS-LRP as a lesion with a maximum lipid core burden index of 4 mm [LCBI4mm] > 500 in the culprit plaque. Clinical demographics, angiographic, and OCT findings were compared between the patients with NIRS-LRP (n = 54) vs. those without NIRS-LRP (n = 86). Uni- and multivariable logistic regression analyses were performed to examine the independent OCT morphological predictors for NIRS-LRP. Results: Clinical demographics showed no significant differences between the two groups. The angiographic minimum lumen diameter was smaller in the NIRS-LRP group than in the non- NIRS-LRP group. In OCT analysis, the minimum flow area was smaller; lipid angle, lipid length, the prevalence of thin-cap fibroatheroma, and cholesterol crystals were greater in the NIRS-LRP group than in the non-NIRS-LRP group. Plaque rupture and thrombi were more frequent in the NIRS-LRP group, albeit not significant. In a multivariable logistic regression analysis, presence of thin-cap fibroatheroma [odds ratio (OR): 2.56; 95% CI: 1.12 to 5.84; p = 0.03] and cholesterol crystals (OR: 2.90; 95% CI: 1.20 to 6.99; p = 0.02) were independently predictive of NIRS-LRP. Conclusions: In ACS culprit lesions, OCT-detected thin-cap fibroatheroma and cholesterol crystals rather than plaque rupture and thrombi were closely associated with a great lipid-core burden.

10.
Circ Cardiovasc Interv ; 15(2): e011045, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35167332

RESUMEN

BACKGROUND: Coronary access (CA) after transcatheter aortic valve replacement (TAVR) with supra-annular transcatheter heart valves (THV) can be challenging. Specific Evolut R/Pro and Acurate Neo THVs orientations are associated with reduced neo-commissure overlap with coronary ostia, while SAPIEN 3 THV cannot be oriented. With the ALIGN-ACCESS study (TAVR With Commissural Alignment Followed by Coronary Access), we investigated the impact of commissural alignment on the feasibility of CA after TAVR. METHODS: We performed coronary angiography after TAVR with intra-annular SAPIEN 3, supra-annular Evolut R/Pro, and Acurate Neo THVs in 206 patients. Evolut THVs were implanted aiming for commissure alignment. Alignment of Acurate Neo was retrospectively assessed in 36, intentionally attempted in 26 cases. The primary end point was the rate of unfeasible and nonselective CA after TAVR. RESULTS: Thirty-eight percent of patients received SAPIEN 3, 31.1% Evolut Pro/R, 30.1% Acurate Neo THV. Final valve orientation was favorable to commissural alignment in 85.9% of Evolut and 69.4% of Acurate Neo cases (with intentional alignment successful in 88.5%). Selective CA was higher for SAPIEN 3 than for aligned and misaligned supra-annular THVs (95% versus 71% versus 46%, P<0.001). Cannulation of at least one coronary was unfeasible with 11% misaligned supra-annular, 3% aligned supra-annular, and 0% SAPIEN 3 THVs. Independent predictors of unfeasible/nonselective CA were implantation of a misaligned supra-annular THV (odds ratio, 4.59 [95% CI, 1.81-11.61]; P<0.01), sinus of Valsalva height (odds ratio, 0.83 [95% CI, 0.7-0.98]; P=0.03), and THV-sinus of Valsalva relation (odds ratio, 1.06 [95% CI, 1.02-1.1]; P<0.01). CONCLUSIONS: Commissural alignment improves the rate of selective CA after TAVR with supra-annular THVs. Nevertheless, aligned supra-annular THVs carry higher risk of unfeasible/nonselective CA than SAPIEN 3. Patients with a misaligned supra-annular THV, low sinus of Valsalva, and higher THV-sinus of Valsalva relation are at highest risk of impaired CA after TAVR.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Humanos , Diseño de Prótesis , Estudios Retrospectivos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento
11.
Sports Biomech ; : 1-15, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34784836

RESUMEN

The three-dimensional (3D) motion of lower-limb joints is evaluated during various sports. However, few studies have reported the 3D lower-limb joint movement during undulatory underwater swimming (UUS). This study aimed to investigate the relationship between 3D lower-limb kinematics and forward-swimming velocity during UUS at maximal velocity. A total of 26 male international- and national-level swimmers were assessed during UUS using a motion-capture system. The 3D angle and angular velocity of the lower-limb joints were calculated and relationships between forward-swimming velocity, angle, and angular velocity were investigated using correlation analysis. The peak angular velocities of hip internal and external rotation were significantly correlated with forward-swimming velocity (r = .48, p = .01 and r =-.74, p < .01, respectively). Peak hip internal rotation was observed at the middle of down-kicking (25% kick cycle, 243 ∘/s), whereas peak external rotation was observed at the terminal of down-kicking (50% kick cycle, -351 ∘/s). The swimmers showed a higher peak angular velocity of hip internal/external rotation with a large active range of motion for hip rotation. The swimmers moved their lower-limb joints three-dimensionally, and aside from flexion/extension movements, and hip rotation may increase UUS proficiency.

12.
Proc Natl Acad Sci U S A ; 118(20)2021 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-33980712

RESUMEN

We use polarization-resolved electronic Raman spectroscopy to study quadrupolar charge dynamics in a nonmagnetic [Formula: see text] superconductor. We observe two types of long-wavelength [Formula: see text] symmetry excitations: 1) a low-energy quasi-elastic scattering peak (QEP) and 2) a broad electronic continuum with a maximum at 55 meV. Below the tetragonal-to-orthorhombic structural transition at [Formula: see text], a pseudogap suppression with temperature dependence reminiscent of the nematic order parameter develops in the [Formula: see text] symmetry spectra of the electronic excitation continuum. The QEP exhibits critical enhancement upon cooling toward [Formula: see text] The intensity of the QEP grows with increasing sulfur concentration x and maximizes near critical concentration [Formula: see text], while the pseudogap size decreases with the suppression of [Formula: see text] We interpret the development of the pseudogap in the quadrupole scattering channel as a manifestation of transition from the non-Fermi liquid regime, dominated by strong Pomeranchuk-like fluctuations giving rise to intense electronic continuum of excitations in the fourfold symmetric high-temperature phase, to the Fermi liquid regime in the broken-symmetry nematic phase where the quadrupole fluctuations are suppressed.

13.
PLoS One ; 16(5): e0251699, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33989342

RESUMEN

PURPOSE: The aim of this study was to investigate the frequency of eyedrop instillation failure and its related physical and visual function factors among glaucoma patients who used hypotensive eyedrops daily. SUBJECTS AND METHODS: Patients with a history of self-instillation of one or more ocular hypotensive ophthalmic solutions for six or more months were enrolled. Definitions of instillation failure were eyedrop instillation other than on the eye surface; eyedrop contact with eyelashes; eyedrop bottle tip contact with the eyelashes, eye surface or ocular adnexa; or two or more drops instilled with one instillation trial. To clarify factors related to instillation failure, we used visual function tests and investigated cervical spine extension angles during instillation, pinching strength, physical ataxia (evaluated using the Scale for the Assessment and Rating of Ataxia), motor dysfunction of the upper limbs (evaluated using the Disabilities of the Arm, Shoulder and Hand questionnaire), and vision quality (evaluated using the National Eye Institute Visual Function Questionnaire 25). RESULTS: Of 103 total subjects, 61.2% satisfied the definition of instillation failure. Instillation of the eyedrop other than at the cul-desac (76.2%) was the most frequent reason for failure, followed by contact of the tip of the eyedrop bottle (22.2%) and instillation of the same or more than two eyedrops in a single attempt (11.1%). Advanced age, a shallow cervical spine extension angle, weak pinching strength, poor motor dysfunction of the upper limbs, the degree of ataxia, poor best-corrected visual acuity, and visual field scores were significant risk factors for instillation failure. Vision quality may have some relation to instillation failure. CONCLUSION: It is highly recommended that instillation failure be routinely investigated even among patients with adequate experience using eyedrops and that correct therapies are chosen in a patient-based fashion.


Asunto(s)
Glaucoma/tratamiento farmacológico , Glaucoma/fisiopatología , Soluciones Oftálmicas/administración & dosificación , Equilibrio Postural , Encuestas y Cuestionarios , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
14.
Curr Cardiol Rep ; 23(3): 15, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33495895

RESUMEN

PURPOSE OF REVIEW: In this review, we discuss about the reasons behind the failure of the Absorb bioresorbable vascular scaffold (BVS) device and about the challenges the future holds for the next generation of the bioresorbable scaffold (BRS) technology. RECENT FINDINGS: Absorb BVS was burdened by intrinsic structural limitations which resulted in augmented rates of device thrombosis and clinical adverse events compared to current-generation metallic stent. Nevertheless, new generation devices with novel design and materials are in development. Second generation BRS have enhanced mechanical strength, smaller footprints, less thrombogenicity and modified bioresorption. These features, paired with proper patient and lesion selection and optimal "user-friendly" implant techniques, could possibly overcome the previous BRS generation limitations, rekindling physicians, and industry interest on this promising technology.


Asunto(s)
Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Implantes Absorbibles , Enfermedad de la Arteria Coronaria/cirugía , Humanos , Diseño de Prótesis , Factores de Tiempo , Resultado del Tratamiento
15.
Catheter Cardiovasc Interv ; 97(4): E536-E543, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32584507

RESUMEN

BACKGROUND: Stroke is a feared complication of transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR). OBJECTIVES: With this meta-analysis we aimed to evaluate the incidence of 30-day stroke with TAVR and SAVR focusing on its possible correlation with surgical risk. METHODS: Major electronic databases were searched for studies published between January 2002 and October 2019 reporting the rates of 30-day stroke after TAVR and SAVR. Data were pooled using fixed- and random-effects models. The primary outcome of the study was stroke rate within 30-day from TAVR or SAVR. Results were stratified according to surgical risk score (high, intermediate and low). RESULTS: A total of 23 studies were identified (TAVR: 14,589 patients; SAVR: 11,681 patients). Regardless of the model used, in the overall population TAVR was associated with a significant reduction in the risk of stroke compared with SAVR (fixed effect: OR 0.78, 95% CI 0.66-0.92, p = .003; random-effects: OR 0.80, 95% CI 0.64-1.00, p = .045). Rates of 30-day stroke after TAVR and SAVR were not significantly different in the high- (OR 1.01, 95% CI 0.44-1.98, p = .105) and intermediate-risk groups (OR 0.92, 95% CI 0.63-1.36, p = .319), while low-risk patients had a lower rate of 30-day stroke after TAVR than SAVR (OR 0.65, 95% CI 0.50-0.83, p < .001). Meta-regression showed a significant association between surgical risk score and 30-day stroke rate (p = .007). CONCLUSIONS: TAVR is associated with a lower risk of 30-day stroke compared with SAVR, mainly as a result of the significant advantage observed in patients at low surgical risk.


Asunto(s)
Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Accidente Cerebrovascular , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento
16.
Eur Heart J ; 42(4): 308-319, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33284979

RESUMEN

AIMS: After percutaneous coronary intervention (PCI) with second-generation drug-eluting stent (DES), whether short dual antiplatelet therapy (DAPT) followed by single antiplatelet therapy (SAPT) with a P2Y12 receptor inhibitor confers benefits compared with prolonged DAPT is unclear. METHODS AND RESULTS: Multiple electronic databases, including PubMed, Scopus, Web of Sciences, Ovid, and ScienceDirect, were searched to identify randomized clinical trials comparing ≤3 months of DAPT followed by P2Y12 inhibitor SAPT vs. 12 months of DAPT after PCI with second-generation DES implantation. The primary and co-primary outcomes of interest were major bleeding and stent thrombosis 1 year after randomization. Summary hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by fixed-effect and random-effects models. Multiple sensitivity analyses including random-effects models 95% CI adjustment were applied. A sensitivity analysis comparing trials using P2Y12 inhibitor SAPT with those using aspirin SAPT was performed. A total of five randomized clinical trials (32 145 patients) were available. Major bleeding was significantly lower in the patients assigned to short DAPT followed by P2Y12 inhibitor SAPT compared with those assigned to 12-month DAPT (random-effects model: HR 0.63, 95% 0.45-0.86). No significant differences between groups were observed in terms of stent thrombosis (random-effects model: HR 1.19, 95% CI 0.86-1.65) and the secondary endpoints of all-cause death (random-effects model: HR 0.85, 95% CI 0.70-1.03), myocardial infarction (random-effects model: HR 1.05, 95% CI 0.89-1.23), and stroke (random-effects model: HR 1.08, 95% CI 0.68-1.74). Sensitivity analyses showed overall consistent results. By comparing trials testing ≤3 months of DAPT followed by P2Y12 inhibitor SAPT vs. 12 months of DAPT with trials testing ≤3 months of DAPT followed by aspirin SAPT vs. 12-month of DAPT, there was no treatment-by-subgroup interaction for each endpoint. By combining all these trials, regardless of the type of SAPT, short DAPT was associated with lower major bleeding (random-effects model: HR 0.63, 95% CI 0.48-0.83) and no differences in stent thrombosis, all-cause death, myocardial infarction, and stroke were observed between regimens. CONCLUSION: After second-generation DES implantation, 1-3 months of DAPT followed by P2Y12 inhibitor SAPT is associated with lower major bleeding and similar stent thrombosis, all-cause death, myocardial infarction, and stroke compared with prolonged DAPT. Whether P2Y12 inhibitor SAPT is preferable to aspirin SAPT needs further investigation.


Asunto(s)
Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Quimioterapia Combinada , Humanos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Antagonistas del Receptor Purinérgico P2Y , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
17.
Circ Arrhythm Electrophysiol ; 14(1): e009028, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33306415

RESUMEN

BACKGROUND: Conduction disturbances after transcatheter aortic valve replacement (TAVR) are often transient. Limited data exist on anatomic factors predisposing to pacemaker dependency after TAVR. We sought to assess the rate and the possible predictors of pacemaker dependency after TAVR. METHODS: Consecutive patients undergoing pacemaker implantation up to 30 days after TAVR between May 2014 and September 2019 were included. Baseline electrocardiographic, computed tomography, and procedural characteristics were collected, including valve implantation depth and membranous septum length, an anatomic surrogate of the distance between the aortic annulus and the His bundle. Pacemaker dependency at 30 days and 1 year and all-cause mortality during follow-up were evaluated. RESULTS: Of 728 TAVR patients, 112 (53.5% men; median age, 81 years) underwent pacemaker implantation after TAVR. Of these, 44.6% (50 of 112) were pacemaker dependent at 30 days and 46.7% (36 of 77) at 1 year. By multivariate analysis, independent predictors of 30-day pacemaker dependency included left ventricular outflow tract calcifications under the left coronary cusp (odds ratio, 5.69 [95% CI, 1.45-22.31]; P=0.013) and a difference between membranous septum length and implantation depth (ΔMSID) ≥3 mm (odds ratio, 7.58 [95% CI, 2.07-27.78]; P=0.002). Conversely, membranous septum length and implantation depth alone were not associated with pacemaker dependency (odds ratio, 0.79 [95% CI, 0.60-1.05]; P=0.11 and odds ratio, 1.11 [95% CI, 0.99-1.24]; P=0.08). At a median follow-up of 28.1 (11.7-48.6) months, pacemaker-dependent patients did not show a worse survival (P=0.26). CONCLUSIONS: Less than half of the patients undergoing pacemaker implantation after TAVR are pacemaker-dependent at midterm follow-up. ΔMSID ≥3 mm and the presence of left ventricular outflow tract calcifications under the left coronary cusp, but not membranous septum length nor implantation depth alone, are predictive of long-term pacemaker dependency after TAVR, thus influencing device selection and programming.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Arritmias Cardíacas/prevención & control , Marcapaso Artificial , Complicaciones Posoperatorias/prevención & control , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Anciano , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico , Arritmias Cardíacas/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Complicaciones Posoperatorias/etiología , Pronóstico , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
18.
G Ital Cardiol (Rome) ; 21(11 Suppl 1): 35S-44S, 2020 11.
Artículo en Italiano | MEDLINE | ID: mdl-33295333

RESUMEN

Transcatheter aortic valve implantation (TAVI) has been a revolution in the treatment of severe aortic stenosis evolving to a high procedural success rate and low rate of complications. Embolization of the percutaneous device is a rare but potentially life-threatening complication. The spectrum of clinical manifestations ranges between incidental finding on cardiac imaging to cardiogenic shock or cardiac arrest. Data about predictors and management of transcatheter heart valve embolization are scarce and mostly anecdotical. Management strategies are related to the type, the size, the location of the embolized device, the timing of diagnosis, and the clinical presentation of the patient. According to recent data from TRAVEL registry, device embolization and migration occur in approximately 1% of the patients and is responsible for increased morbidity and mortality. However, in a considerable proportion of cases it could have been prevented, hence structural interventionalists should plan the procedures carefully and know thoroughly the risk factors for device embolization. Increased awareness of predisposing factors, preventive measures, and appropriate bail-out options and techniques are strongly advisable. This paper is a review of the incidence, and outcomes of percutaneous prosthesis embolization during TAVI. It also suggests an integrated algorithmic approach for the management of device embolization incorporating both percutaneous and surgical techniques.


Asunto(s)
Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Cateterismo Cardíaco , Humanos , Factores de Riesgo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento
19.
Sci Adv ; 6(45)2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33158862

RESUMEN

The crossover from the superconductivity of the Bardeen-Cooper-Schrieffer (BCS) regime to the Bose-Einstein condensation (BEC) regime holds a key to understanding the nature of pairing and condensation of fermions. It has been mainly studied in ultracold atoms, but in solid systems, fundamentally previously unknown insights may be obtained because multiple energy bands and coexisting electronic orders strongly affect spin and orbital degrees of freedom. Here, we provide evidence for the BCS-BEC crossover in iron-based superconductors FeSe1 - x S x from laser-excited angle-resolved photoemission spectroscopy. The system enters the BEC regime with x = 0.21, where the nematic state that breaks the orbital degeneracy is fully suppressed. The substitution dependence is opposite to the expectation for single-band superconductors, which calls for a new mechanism of BCS-BEC crossover in this system.

20.
Materials (Basel) ; 13(20)2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33076490

RESUMEN

Intraocular stability during or after cataract and glaucoma filtration surgeries and vitreous surgery with a gas/silicone oil tamponade might differ among intraocular lenses (IOLs). We used six different one-piece IOL models and measured the force that displaced the IOLs from the vitreous cavity to anterior chamber as a measure of stability against the pressure gradient between the anterior and posterior IOL surfaces. We measured IOL hardness, haptics junction area, and posterior IOL bulge to identify what determines the IOL displacement force. The KOWA YP2.2 IOL (1.231 mN) required significantly greater force than the HOYA XY1 (0.416 mN, p = 0.0004), HOYA 255 (0.409 mN, p = 0.0003), Alcon SN60WF (0.507 mN, p = 0.0010), and Nidek NS60YG (0.778 mN, p = 0.0186) IOLs; J&J ZCB00V IOL (1.029 mN) required greater force than the HOYA XY1 (p = 0.0032) and HOYA 255 (p = 0.0029) IOLs; the Nidek NS60YG IOL required greater force than the HOYA 255 (p = 0.0468) IOL. The haptics junction area was correlated positively with the IOL displacement force (r = 0.8536, p = 0.0306); the correlations of the other parameters were non-significant. After adjusting for any confounding effects, the haptics junction area was correlated significantly with the IOL displacement force (p = 0.0394); the IOL hardness (p = 0.0573) and posterior IOL bulge (p = 0.0938) were not. The forces that displace IOLs anteriorly differed among one-piece soft-acrylic IOLs, and the optics/haptics junction area was the major force determinant.

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