Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Chem Soc Rev ; 53(17): 8878-8902, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39106108

RESUMEN

The inherent limitations of lithium (Li)-ion batteries have sparked interest in exploring alternative technologies, especially those relying on metallic anodes: monovalent Li and divalent zinc (Zn), magnesium (Mg), and calcium (Ca) metals. In particular, Mg and Ca metal batteries offer significant advantages based on the natural abundance of their raw materials and high energy-storage capabilities resulting from the bivalency of the carrier ions. Yet, these battery systems are far from commercialization, and the lack of reliable electrolytes constitutes a primary concern. The formation of ion-insulating passivation layers on these metallic anodes and their inferior desolvation kinetics have long been recognized as formidable hurdles in the way of optimizing the electrolyte composition. These impediments call for innovative strategies in electrolyte engineering and an extensive analysis of the resulting solid-electrolyte-interphase (SEI) layer. In this review, we introduce recent pioneering studies of divalent Mg and Ca metal batteries that have been concerned with these issues. This review particularly focuses on drawing an analogy with Li and Zn metal batteries in terms of the relative advancement and by benchmarking against the strategies developed for these analogous systems. The areas of interest include a fundamental understanding of the thermodynamics and evolution of the morphology of metallic anodes, a correlation between the electrolyte and SEI compositions, state-of-the-art electrolyte strategies to realize reversible (de)plating of Mg and Ca, and new perspectives on the SEI properties and their relevance to corrosion and the calendar life. We finally encourage researchers in the community to delve into these emerging areas by linking with successful stories in the analogous systems, but identifying distinct aspects of Mg and Ca batteries that still require attention.

2.
J Environ Manage ; 370: 122574, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39321675

RESUMEN

Non-thermal plasma has been an emerging technology for water treatment for decades. In this study, we have designed and fabricated a bubbling plasma batch reactor using an atmospheric pressure dielectric barrier discharge with a hydrophobic porous membrane. The reactor performance is assessed for purifying synthetic contaminated water samples containing chemical contaminant sulfamethoxazole (SMX), a widely used antibiotic, and biological contaminant E. coli K12. The SMX decontamination tests indicate that the degradation process is not first-order and the reaction rate dwindle with increasing initial concentration. The yield at 50% removal achieves its highest value of 8.12 g/kWh for 50 mg/L SMX sample. For inactivation of E. coli K12 tests, the inactivation process is also not first-order, and the pathogen is completely inactivated for 102 CFU/mL and 104 CFU/mL cases after 10 min and 45 min of plasma treatment, respectively. For the 108 CFU/mL sample, a 5-log reduction is achieved after 60 min of treatment. The developed plasma reactor can achieve fast deployment in point of use, low cost for manufacturing, and simple for maintenance. Moreover, it can be used for in-situ water purification in future long duration crewed space missions as well as tackling with water pollution issues on our planet.

3.
J Am Chem Soc ; 145(29): 15776-15787, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37436721

RESUMEN

Aqueous zinc-ion batteries (AZIBs) are receiving increasing attention for power-grid energy storage systems. Nevertheless, warranting long-term reversible operation is not trivial owing to uncontrolled interfacial phenomena related to zinc dendritic growth and parasitic reactions. Herein, the addition of hexamethylphosphoramide (HMPA) to the electrolyte revealed the surface overpotential (|ηs|) to be a key metric of the reversibility. HMPA adsorbs onto active sites on the zinc metal surface, raising the surface overpotential toward lowering the nucleation energy barrier and decreasing the critical size (rcrit) of nuclei. We also correlated the observed interface-to-bulk properties by the Wagner (Wa) dimensionless number. The controlled interface enables a Zn|V6O13 full cell to retain 75.97% capacity for 2000 cycles, with a capacity loss of only 1.5% after 72 h resting. Our study not only delivers AZIBs with unparalleled cycling and storage performance but also proposes surface overpotential as a key descriptor regarding the sustainability of AZIB cycling and storage.

4.
J Cardiovasc Electrophysiol ; 34(1): 189-196, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36349711

RESUMEN

INTRODUCTION: This study aimed to elucidate the relationship between premature ventricular complexes (PVCs) and right ventricular (RV) dysfunction, and the effects of radiofrequency catheter ablation (RFCA) on RV function. METHODS: A total of 110 patients (age, 50.8 ± 14.4 years; 30 men) without structural heart disease who had undergone RFCA for RV outflow tract (RVOT) PVCs were retrospectively included. RV function was assessed using fractional area change (FAC) and global longitudinal strain (GLS) before and after RFCA. Clinical data were compared between the RV dysfunction (n = 63) and preserved RV function (n = 47) groups. The relationship between PVC burden and RV function was analyzed. Change in RV function before and after RFCA was compared between patients with successful and failed RFCA. RESULTS: PVC burden was significantly higher in the RV dysfunction group than in the preserved RV function group (p < .001). FAC and GLS were significantly worse in proportion to PVC burden (p < .001 and p < .001, respectively). The risk factor associated with RV dysfunction was PVC burden [odds ratio (95% confidence interval), 1.092 (1.052-1.134); p < .001]. Improvement in FAC (13.0 ± 8.7% and -2.5 ± 5.6%, respectively; p < .001) and GLS (-6.8 ± 5.7% and 2.1 ± 4.2%, respectively; p < .001) was significant in the patients with successful RFCA, compared to the patients in whom RFCA failed. CONCLUSIONS: Frequent RVOT PVCs are associated with RV dysfunction. RV dysfunction is reversible by successful RFCA.


Asunto(s)
Ablación por Catéter , Disfunción Ventricular Derecha , Complejos Prematuros Ventriculares , Masculino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Función Ventricular Derecha , Resultado del Tratamiento , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Complejos Prematuros Ventriculares/diagnóstico , Complejos Prematuros Ventriculares/cirugía , Complejos Prematuros Ventriculares/complicaciones , Ablación por Catéter/efectos adversos , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología , Disfunción Ventricular Derecha/cirugía
5.
Nano Lett ; 22(6): 2194-2201, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35240776

RESUMEN

Stochastic optical fluctuation imaging (SOFI) generates super-resolution fluorescence images by emphasizing the positions of fluorescent emitters via statistical analysis of their on-and-off blinking dynamics. In SOFI with speckle illumination (S-SOFI), the diffraction-limited grain size of the far-field speckles prevents independent blinking of closely located emitters, becoming a hurdle to realize the full super-resolution granted by SOFI processing. Here, we present a surface-sensitive super-resolution technique exploiting dynamic near-field speckle illumination to bring forth the full super-resolving power of SOFI without blinking fluorophores. With our near-field S-SOFI technique, up to 2.8- and 2.3-fold enhancements in lateral spatial resolution are demonstrated with computational and experimental fluorescent test targets labeled with conventional fluorophores, respectively. Fluorescent beads separated by 175 nm are also super-resolved by near-field speckles of 150 nm grain size, promising sub-100 nm resolution with speckle patterns of much smaller grain size.


Asunto(s)
Iluminación , Imagen Óptica , Colorantes Fluorescentes , Microscopía Fluorescente/métodos , Imagen Óptica/métodos
6.
Opt Lett ; 47(10): 2482-2485, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35561381

RESUMEN

We introduce a novel, to the best of our knowledge, method to increase the bandwidth in holographic displays. Here, multi-angle illumination using multiple laser diodes (LDs) is adopted to expand the limited diffraction angle of the spatial light modulator (SLM). To solve the problem of signal repetitions caused by sharing the same SLM pattern, we use a random binary mask (BM). We demonstrate via simulations and experiments that our method effectively increases the bandwidth with sufficient image quality. Furthermore, the speckle noise, a critical issue of the holographic display that decreases the contrast and is potentially harmful to eyes, is reduced by the advantage of incoherent summation in the reconstruction plane. We believe that this method is a practical approach that can expand the bandwidth of the holographic display by alleviating the bottleneck of hardware limitations.

7.
Angew Chem Int Ed Engl ; 61(47): e202211589, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36180384

RESUMEN

Despite substantial progresses, in aqueous zinc ion batteries (AZIBs), developing zinc metal anodes with long-term reliable cycling capabilities is nontrivial because of dendritic growth and related parasitic reactions on the zinc surface. Here, we exploit the tip-blocking effect of a scandium (Sc3+ ) additive in the electrolyte to induce uniform zinc deposition. Additional to the tri-valency of Sc3+ , the rigidity of its hydration shell effectively prevents zinc ions from concentrating at the surface tips, enabling highly stable cycling under challenging conditions. The shell rigidity, quantified by the rate constant of the exchange reaction (kex ), is established as a key descriptor for evaluating the tip-blocking effect of redox-inactive cations, explaining inconsistent results when only the valence state is considered. Moreover, the tip-blocking effect of Sc3+ is maintained in blends with organic solvents, allowing the zinc anode to cycle reliably even at -40 °C without corrosion.

8.
Opt Lett ; 46(17): 4176-4179, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34469968

RESUMEN

We propose a compact tomographic near-eye display by combining a micro-electro-mechanical systems (MEMS) scanning mirror device, focus tunable lens, and a single light-emitting diode source. A holographic optical element was used to elaborately focus the light source into the MEMS scanning mirror while providing further miniaturization. We implemented a drastically downsized multifocal display system that expresses a depth range of 4.8 D with eight focal planes by synchronizing these modules. Furthermore, the planar images are optimized to achieve correct retinal scenes at each accommodation state. The simulated and experimental results verify that the suggested near-eye display system can provide three-dimensional virtual images while showing physical feasibility.


Asunto(s)
Holografía , Lentes , Sistemas Microelectromecánicos , Miniaturización , Tomografía
9.
Catheter Cardiovasc Interv ; 98(3): E332-E341, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33817960

RESUMEN

OBJECTIVES: We investigated whether the dual antiplatelet therapy (DAPT) score (DS) predicts clinical outcome in an East-Asian population that received exclusively second generation drug-eluting stent (DES). BACKGROUNDS: It is uncertain whether the DS could adequately risk stratify patients exclusively receiving second generation DES. METHODS: From the Grand-DES registry, we evaluated patients who were treated with DAPT for at least 12 months and were event-free at 12 months after DES implantation. Patients were classified into two categories: high DS (≧2) (n = 3,157); and low DS (<2) (n = 5,226). The primary ischemic outcome was a composite of stent thrombosis and all myocardial infarction (MI), and the primary bleeding outcome was TIMI major or minor bleeding. A propensity score (PS)-matched analysis was done to correct for baseline differences between extended DAPT group and the conventional group. RESULTS: Among 8,383 subjects, the primary ischemic outcome occurred in 48 patients (0.6%) and the primary bleeding outcome in 49 patients (0.6%). High DS was associated with a higher incidence of ischemic events (ischemic outcome: 0.8% vs. 0.4%, for high vs. low DS, Log-rank p = .039), but not with any differences in bleeding events (Log-rank p = .734). In the PS-matched analysis, extended group was associated with lower risk of composite endpoint of MI, stent thrombosis, or cardiac death in only the high DS group (1.8% vs. 3.7%, Log-rank p = .004; hazard ratio 0.45, 95% confidence interval 0.27-0.76; p = .003 after adjustment). CONCLUSIONS: The DS was an adequate risk stratifier for future ischemic events in East Asians receiving exclusively second generation DES.


Asunto(s)
Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Pueblo Asiatico , Quimioterapia Combinada , Humanos , Intervención Coronaria Percutánea/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
10.
J Korean Med Sci ; 35(40): e366, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33075857

RESUMEN

BACKGROUND: This study aimed to investigate the cardiac manifestations of coronavirus disease 2019 (COVID-19). METHODS: From February to March 2020, we prospectively and retrospectively enrolled consecutive patients diagnosed with COVID-19. Patient's data such as the demographic characteristics, symptoms, vital signs, laboratory and radiologic findings, electrocardiographic, and echocardiographic data, including the global longitudinal strain (GLS) of both ventricles, were obtained. RESULTS: Forty patients (median age, 58 years; 50% men) were enrolled in the initial analysis. Patients were classified into severe and nonsevere groups based on the current guidelines. The 13 patients in the severe group were significantly older, had a greater prevalence of bilateral pneumonia and leukocytosis, and higher aspartate transaminase levels than patients in the nonsevere group. Patients in the severe group had a slightly lower left ventricular ejection fraction (LVEF) than those in the nonsevere group (median [interquartile range], 61.0% [58.5%, 62.3%] vs. 66.7% [60.6%, 69.8%], P = 0.015). In a subgroup of 34 patients in whom GLS could be analyzed, patients in the severe group had a significantly impaired left ventricular GLS (LVGLS) than those in the nonsevere group (-18.1% [-18.8%, -17.1%] vs. -21.7% [-22.9%, -19.9%], P = 0.001). There were no significant differences in total wall (RVGLStotal, -19.3% [-23.9%, -18.4%] vs. -24.3% [-26.0%, -22.6%], P = 0.060) and free wall (RVGLSfw, -22.7% [-27.2%, -18.6%] vs. -28.8% [-30.4%, -24.1%], P = 0.066) right ventricle GLS (RVGLS). CONCLUSION: Patients with severe COVID-19 had lower LVEF and LVGLS. RVGLS was not different between patients with severe and nonsevere COVID-19.


Asunto(s)
Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico , Cardiopatías/diagnóstico , Cardiopatías/virología , Neumonía Viral/complicaciones , Neumonía Viral/diagnóstico , Adulto , Anciano , Betacoronavirus , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Ecocardiografía , Electrocardiografía , Femenino , Corazón/fisiopatología , Ventrículos Cardíacos , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Pandemias , Estudios Prospectivos , Reproducibilidad de los Resultados , Estudios Retrospectivos , SARS-CoV-2 , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/virología , Función Ventricular Izquierda
11.
Int Heart J ; 57(3): 278-84, 2016 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-27150001

RESUMEN

Individuals with intermediate to high cardiac risk for major noncardiac surgery suffer from perioperative myocardial ischemic injury. The purpose of this study was to evaluate the long-term impact of postoperative cardiac troponin elevation on clinical outcome after major noncardiac surgery.Patients (n = 750) aged ≥ 50 years who underwent major noncardiac surgery were eligible for the study. Postoperative cardiac troponin-I data were collected retrospectively and consecutively. The primary outcome measure was allcause mortality. The median follow-up period was 1727 days in all patients.Among 750 patients, 92 (12.2%) showed elevated postoperative troponin-I above 0.10 ng/mL. Operative mortality was 4.1% (31 subjects), and patients with troponin-I elevation showed a higher operative mortality rate (RR: 4.23, 95% CI: 2.67-11.31, P < 0.001). In multivariate Cox regression analysis, a troponin-I concentration above 0.10 ng/mL was associated with all-cause mortality (RR: 1.73, 95% CI: 1.27-2.36, P < 0.001). It should be noted that there was a significant difference between patients with elevated and non-elevated troponin-I in the rate of mortality until 6 months. However, these differences disappeared after 6 months.An elevated troponin-I level conferred an increase in mortality during the 7 year follow-up period after major noncardiac surgery. This difference in mortality was mainly derived from the result within the first 6 months.


Asunto(s)
Efectos Adversos a Largo Plazo , Isquemia Miocárdica , Complicaciones Posoperatorias/sangre , Procedimientos Quirúrgicos Operativos/efectos adversos , Troponina I/sangre , Anciano , Biomarcadores/sangre , Femenino , Estudios de Seguimiento , Humanos , Efectos Adversos a Largo Plazo/etiología , Efectos Adversos a Largo Plazo/mortalidad , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/sangre , Isquemia Miocárdica/etiología , Evaluación de Resultado en la Atención de Salud , Periodo Posoperatorio , Valor Predictivo de las Pruebas , República de Corea/epidemiología , Procedimientos Quirúrgicos Operativos/estadística & datos numéricos , Factores de Tiempo
12.
Phys Rev Lett ; 113(11): 113901, 2014 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-25259979

RESUMEN

Light-matter interaction gives optical microscopes tremendous versatility compared with other imaging methods such as electron microscopes, scanning probe microscopes, or x-ray scattering where there are various limitations on sample preparation and where the methods are inapplicable to bioimaging with live cells. However, this comes at the expense of a limited resolution due to the diffraction limit. Here, we demonstrate a novel method utilizing elastic scattering from disordered nanoparticles to achieve subdiffraction limited imaging. The measured far-field speckle fields can be used to reconstruct the subwavelength details of the target by time reversal, which allows full-field dynamic super-resolution imaging. The fabrication of the scattering superlens is extremely simple and the method has no restrictions on the wavelength of light that is used.

13.
J Cardiovasc Imaging ; 32(1): 22, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39113162

RESUMEN

BACKGROUND: Right ventricular (RV) systolic dysfunction is an established prognostic factor in patients with severe tricuspid regurgitation (TR). However, accurate assessment of RV systolic function using conventional echocardiography remains challenging. We investigated the accuracy of strain measurement using speckle tracking echocardiography (STE) for evaluating RV systolic function in patients with severe TR. METHODS: We included consecutive patients with severe TR who underwent echocardiography and cardiac magnetic resonance imaging (CMR) within 30 days between 2011 and 2023. Two-dimensional STE was used to measure RV free wall longitudinal strain (RVFWLS) and global longitudinal strain (RVGLS). These values were compared with the RV ejection fraction (RVEF) from CMR. RV systolic dysfunction was defined as a CMR-derived RVEF < 35%. RESULTS: A total of 87 patients with severe TR were identified during the study period. Among echocardiographic RV strain measurements, RVFWLS was the best correlate of CMR-derived RVEF (r = -0.37, P < 0.001), followed by RVGLS (r = -0.27, P = 0.012). Receiver operating characteristic (ROC) curve analysis revealed that RVFWLS provided better discrimination of RV systolic dysfunction, yielding an area under the ROC curve (AUC) of 0.770 (95% confidence interval [CI], 0.696-0.800) than RV fractional area change (AUC, 0.615; 95% CI, 0.500-0.859). CONCLUSIONS: In patients with severe TR, STE-derived RVFWLS showed the best correlation with RVEF on CMR and displayed superior discrimination of RV systolic dysfunction compared with the RV fractional area change. This study suggests the potential usefulness of STE in assessing RV systolic function in this population.

14.
Ann Lab Med ; 44(3): 279-288, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38205526

RESUMEN

Background: The mechanism and medical treatment target for degenerative aortic valve disease, including aortic stenosis, is not well studied. In this study, we investigated the effect of clonal hematopoiesis of indeterminate potential (CHIP) on the development of aortic valve sclerosis (AVS), a calcified aortic valve without significant stenosis. Methods: Participants with AVS (valves ≥2 mm thick, high echogenicity, and a peak transaortic velocity of <2.5 m/sec) and an age- and sex-matched control group were enrolled. Twenty-four CHIP genes with common variants in cardiovascular disease were used to generate a next-generation sequencing panel. The primary endpoint was the CHIP detection rate between the AVS and control groups. Inverse-probability treatment weighting (IPTW) analysis was performed to adjust for differences in baseline characteristics. Results: From April 2020 to April 2022, 187 participants (125 with AVS and 62 controls) were enrolled; the mean age was 72.6±8.5 yrs, and 54.5% were male. An average of 1.3 CHIP variants was observed. CHIP detection, defined by a variant allele frequency (VAF) of ≥0.5%, was similar between the groups. However, the AVS group had larger CHIP clones: 49 (39.2%) participants had a VAF of ≥1% (vs. 13 [21.0%] in the control group; P=0.020), and 25 (20.0%) had a VAF of ≥2% (vs. 4 [6.5%]; P=0.028). AVS is independently associated with a VAF of ≥1% (adjusted odds ratio: 2.44, 95% confidence interval: 1.11-5.36; P=0.027). This trend was concordant and clearer in the IPTW cohort. Conclusions: Participants with AVS more commonly had larger CHIP clones than age- and sex-matched controls. Further studies are warranted to identify causality between AVS and CHIP.


Asunto(s)
Estenosis de la Válvula Aórtica , Calcinosis , Humanos , Masculino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Femenino , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Hematopoyesis Clonal , Esclerosis/patología , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/genética , Estenosis de la Válvula Aórtica/patología , Calcinosis/patología
15.
J Glob Health ; 14: 04210, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39388680

RESUMEN

Background: Although socioeconomic status (SES) is considered a risk factor for cardio-cerebrovascular diseases (CCVDs), few studies have examined this association. In this cross-sectional study, we aimed to assess the prevalence and trends of CCVDs across different SES groups over a 12-year period in a representative Korean population. Methods: We analysed 47 745 economically active adults aged ≥30 and <65 years from 97 622 patients in the Korean National Health and Nutrition Examination Survey (2007-18), where a new independent sample of the population was examined each year. We categorised the participants into four groups based on education level and income. The prevalence of hypertension, diabetes mellitus, dyslipidaemia, and CCVD, including angina, myocardial infarction, and stroke, was analysed at four-year intervals. Results: Average age, urban residence, white-collar occupation, and body mass index >30 increased, whereas CCVD prevalence did not change significantly (P = 0.410) over the study period. Low education (odds ratio (OR) = 1.24; 95% confidence interval (CI) = 1.04-1.47, P < 0.001) and low income (OR = 1.14; 95% CI = 1.02-1.28, P = 0.017) were significant determinants of CCVD in addition to existing traditional risk factors. CCVD prevalence was significantly higher in both the low-education and low-income groups compared to the high-education and high-income groups every four years, with no significant change in this gap over the study period (P = 0.239). Conclusions: Despite the increase in the elderly population and the prevalence of obesity, the incidence of CCVDs in Korea has remained unchanged. Individuals with low education or low income had a significantly higher prevalence of CCVD, with the lowest SES group, defined by both low education and low income, consistently having the highest prevalence of CCVDs.


Asunto(s)
Enfermedades Cardiovasculares , Trastornos Cerebrovasculares , Humanos , Estudios Transversales , Femenino , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Adulto , Trastornos Cerebrovasculares/epidemiología , Prevalencia , Enfermedades Cardiovasculares/epidemiología , Disparidades en el Estado de Salud , Factores de Riesgo , Encuestas Nutricionales , Factores Socioeconómicos , Clase Social , Disparidades Socioeconómicas en Salud
16.
Korean Circ J ; 54(4): 203-217, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38654567

RESUMEN

BACKGROUND AND OBJECTIVE: The effects of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) on right ventricular (RV) function are not well known. METHODS: Patients who underwent RFCA for AF and underwent pre- and post-procedural echocardiography were enrolled consecutively. Fractional area change (FAC), RV free-wall longitudinal strain (RVFWSL), and RV 4-chamber strain including the ventricular septum (RV4CSL) were measured. Changes in FAC, RVFWSL, and RV4CSL before and after RFCA were compared among paroxysmal AF (PAF), persistent AF (PeAF), and long-standing persistent AF (LSPeAF) groups. RESULTS: A total of 164 participants (74 PAF, 47 PeAF, and 43 LSPeAF; age, 60.8 ± 9.8 years; men, 74.4%) was enrolled. The patients with PeAF and LSPeAF had worse RV4CSL (p<0.001) and RVFWSL (p<0.001) than those with PAF and reference values. Improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared with the PAF and LSPeAF groups (ΔRV4CSL, 8.4% [5.1, 11.6] in PeAF vs. 1.0% [-1.0, 4.1] in PAF, 1.9% [-0.2, 4.4] in LSPeAF, p<0.001; ΔRVFWSL, 9.0% [6.9, 11.5] in PeAF vs. 0.9% [-1.4, 4.9] in PAF, 1.0% [-1.0, 3.6] in LSPeAF, p<0.001). In patients without recurrence, improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared to the LSPeAF group. CONCLUSIONS: RV systolic function is more impaired in patients with PeAF and LSPeAF than in those with PAF. RV systolic function is more improved after RFCA in patients with PeAF than in those with PAF or LSPeAF.

17.
Front Cardiovasc Med ; 10: 1213557, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900564

RESUMEN

Background: The relative importance of left atrial reservoir strain (LASr) regarding the Heart Failure Association Pre-test assessment, Echocardiography and natriuretic peptide, Functional testing, Final etiology (HFA-PEFF) score, a diagnostic tool for patients with heart failure with preserved ejection fraction (HFpEF), remains unclear. We aimed to identify the relative importance of LASr compared with variables associated with HFpEF and HFA-PEFF scores. Methods: Between August 2021 and July 2022, we obtained retrospective data from the participants visiting a single cardiovascular center with subjective symptoms of heart failure, such as dyspnea or chest discomfort. In total, 2,712 participants with sinus rhythm and ejection fraction of more than 50% were enrolled. Multivariable logistic regression analysis, random forest analysis, and supervised machine learning algorithms were performed to identify the relative importance of LASr to the HFA-PEFF score. Results: The average HFA-PEFF score was 2.4 ± 1.6 points. Two hundred and thirty-eight participants had 5 or 6 points. LASr showed a moderate correlation with the HFA-PEFF score (r = -0.50, p < 0.001). Impaired LASr < 25.2% was an independent variable affecting a high HFA-PEFF score with traditional diastolic function parameters and components of the HFA-PEFF diagnostic algorithm. The odds ratio (OR) [1.74, 95% confidence interval (CI) 1.23-2.47] for LASr was higher compared to that of left ventricular global longitudinal strain (OR 1.59, 95% CI 1.14-2.21), septal E/e' (OR 1.23, 95% CI 0.85-1.77), and relative wall thickness (OR 1.20, 95% CI 0.76-1.89). LASr was also a relatively more important variable in estimating a high HFA-PEFF score than TR-Vmax, septal E/e', septal e', left ventricular mass index, and relative wall thickness, the major echocardiographic components of the HFA-PEFF score. Conclusions: LASr is an important factor with components of the HFA-PEFF score and is a useful tool to assess patients with HFpEF. Clinical Trial Registration: URL: https://clinicaltrials.org. Unique identifiers: NCT05638230.

18.
Int J Cardiol ; 378: 151-158, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36863423

RESUMEN

BACKGROUND: The usefulness of preoperative measurement of left ventricular global longitudinal strain (LVGLS) for predicting prognosis in patients undergoing non-cardiac surgery has not been evaluated. We analyzed the prognostic value of LVGLS in predicting postoperative 30-day cardiovascular events and myocardial injury after non-cardiac surgery (MINS). METHODS: This prospective cohort study was conducted in two referral hospitals and included 871 patients who underwent non-cardiac surgery <1 month after preoperative echocardiography. Those with ejection fraction <40%, valvular heart disease, and regional wall motion abnormality were excluded. The co-primary endpoints were the (1) composite incidence of all-cause death, acute coronary syndrome (ACS), and MINS and (2) composite incidence of all-cause death and ACS. RESULTS: Among the 871 participants enrolled (mean age: 72.9 years; female: 60.8%), there were 43 cases of the primary endpoint (4.9%): 10 deaths, 3 ACS, and 37 MINS. Participants with impaired LVGLS (≤16.6%) had a higher incidence of the co-primary endpoints (log-rank P < 0.001 and 0.015) than those without. The result was similar after adjustment with clinical variables and preoperative troponin T levels (hazard ratio = 1.30, 95% confidence interval [CI] = 1.03-1.65; P = 0.027). In sequential Cox analysis and net reclassification index, LVGLS had an incremental value for predicting the co-primary endpoints after non-cardiac surgery. Among the 538 (61.8%) participants who underwent serial troponin assay, LVGLS predicted MINS independently from the traditional risk factors (odds ratio = 3.54, 95% CI = 1.70-7.36; P = 0.001). CONCLUSIONS: Preoperative LVGLS has an independent and incremental prognostic value in predicting early postoperative cardiovascular events and MINS. CLINICAL TRIAL REGISTRATION: URL: https://trialsearch.who.int/. Unique identifiers: KCT0005147.


Asunto(s)
Enfermedades Cardiovasculares , Tensión Longitudinal Global , Anciano , Femenino , Humanos , Ecocardiografía , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Volumen Sistólico , Estudios de Cohortes
19.
Front Cardiovasc Med ; 10: 1305824, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38045912

RESUMEN

Introduction: Amlodipine, widely used as a first-line treatment for hypertension, has inconclusive clinical evidence regarding its efficacy in patients with heart failure. This retrospective cohort study aimed to investigate the clinical effectiveness of amlodipine treatment after hospitalization for heart failure in patients with dilated cardiomyopathy (DCMP). Methods: A total of 20,851 patients who were diagnosed with DCMP and admitted for heart failure between 2005 and 2016 according to Korean nationwide medical insurance service database were enrolled. Amlodipine use was defined as its prescription at the time of discharge and for at least 180 days within a year. The primary outcome was all-cause death, and the secondary outcome was heart failure rehospitalization during a 5-year period. The outcomes between patients who received amlodipine (n = 6,798) and those who did not (n = 14,053) were compared. Results: During the 5-year follow-up, the group treated with amlodipine exhibited a significantly lower risk of all-cause death and heart failure rehospitalization than the group not treated with amlodipine [all-cause death: adjusted hazard ratio (HR): 0.64, 95% confidence interval (CI): 0.59-0.70, p < 0.001; cardiovascular death: adjusted HR: 0.71, 95% CI: 0.62-0.81, p < 0.001; heart failure rehospitalization: adjusted HR: 0.92, 95% CI: 0.86-0.98, p = 0.006]. In a subgroup analysis, amlodipine had a significant impact on decreasing all-cause mortality in older adults, those with a higher systolic blood pressure, and those with a lower Charlson Comorbidity Index. Conclusion: In summary, amlodipine use after hospitalization for heart failure in patients with DCMP was associated with a lower risk of all-cause death and readmission for heart failure.

20.
Nat Commun ; 14(1): 1296, 2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36894583

RESUMEN

Regulating the morphology of lithium plating is the key to extending the cycle life of lithium metal batteries. Fatal dendritic growth is closely related to out-of-plane nucleation on the lithium metal surface. Herein, we report a nearly perfect lattice match between the lithium metal foil and lithium deposits by removing the native oxide layer using simple bromine-based acid-base chemistry. The naked lithium surface induces homo-epitaxial lithium plating with columnar morphologies and lower overpotentials. Using the naked lithium foil, the lithium-lithium symmetric cell maintains stable cycling at 10 mA cm-2 for more than 10,000 cycles, and the full-cell paired with LiFePO4 with high areal capacity of 3.3 mAh cm-2 and practical N/P ratio of 2.5 exhibits 86% capacity retention after 300 cycles. This study elucidates the usefulness of controlling the initial surface state to facilitate homo-epitaxial lithium plating for sustainable cycling of lithium metal batteries.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA