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1.
J Synchrotron Radiat ; 31(Pt 3): 469-477, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38517754

RESUMEN

Various X-ray techniques are employed to investigate specimens in diverse fields. Generally, scattering and absorption/emission processes occur due to the interaction of X-rays with matter. The output signals from these processes contain structural information and the electronic structure of specimens, respectively. The combination of complementary X-ray techniques improves the understanding of complex systems holistically. In this context, we introduce a multiplex imaging instrument that can collect small-/wide-angle X-ray diffraction and X-ray emission spectra simultaneously to investigate morphological information with nanoscale resolution, crystal arrangement at the atomic scale and the electronic structure of specimens.

2.
Circ J ; 87(2): 268-276, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36123011

RESUMEN

BACKGROUND: This study evaluated the association of body mass index (BMI) with adverse clinical outcomes during chronic maintenance antiplatelet monotherapy after percutaneous coronary intervention (PCI) with drug-eluting stents (DES).Methods and Results: Overall, 5,112 patients were stratified (in kg/m2) into underweight (BMI ≤18.4), normal weight (18.5-22.9), overweight (23.0-24.9), obesity (25.0-29.9) and severe obesity (≥30.0) categories with randomized antiplatelet monotherapy of aspirin 100 mg or clopidogrel 75 mg once daily for 24 months. The primary endpoint was the composite of all-cause death, non-fatal myocardial infarction, stroke, readmission due to acute coronary syndrome and major bleeding of Bleeding Academic Research Consortium type ≥3. Compared with normal weight, the risk of primary composite outcomes was higher in the underweight (hazard ratio [HR] 2.183 [1.199-3.974]), but lower in the obesity (HR 0.730 [0.558-0.954]) and severe obesity (HR 0.518 [0.278-0.966]) categories, which is partly driven by the difference in all-cause death. The risk of major bleeding was significantly higher in the underweight (HR 4.140 [1.704-10.059]) than in the normal weight category. A decrease in categorical BMI was independently associated with the increased risk of primary composite outcomes. CONCLUSIONS: Lower BMI is associated with a higher risk of primary composite outcomes, which is primarily related to the events of all-cause death or major bleeding during chronic maintenance antiplatelet monotherapy after PCI with DES.


Asunto(s)
Stents Liberadores de Fármacos , Obesidad Mórbida , Intervención Coronaria Percutánea , Humanos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Aspirina , Índice de Masa Corporal , Stents Liberadores de Fármacos/efectos adversos , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Obesidad Mórbida/tratamiento farmacológico , Obesidad Mórbida/etiología , Delgadez/inducido químicamente , Delgadez/tratamiento farmacológico , Quimioterapia Combinada , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Obesidad/complicaciones , Resultado del Tratamiento
3.
Catheter Cardiovasc Interv ; 98(4): E548-E554, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34137484

RESUMEN

OBJECTIVES: To evaluate the safety and technical utility of the short track sliding (STS) balloon catheter. BACKGROUND: An STS balloon catheter is designed to ensure a low profile at the shaft and perform distal anchoring using a single guidewire. However, its clinical practice with the STS balloon catheter has not been reported. METHODS: This prospective multi-center registry enrolled 100 patients with significant coronary artery disease who had undergone percutaneous coronary intervention using an STS balloon catheter at three hospitals in Korea from March 2019 to July 2020. Overall safety was assessed as any occurrences of device-related malfunction during the pre-dilation of the lesions. Its technical success rates of the kissing balloon technique or the distal anchoring technique using a single guidewire were also evaluated. RESULTS: Of the 118 lesions pre-dilated using the STS balloon, no significant complication was observed except for three significant coronary dissections, which were completely covered with stents. There was no incidence of balloon catheter malfunction, such as fracture, entrapment, or perforation. With 13 attempts of kissing ballooning techniques with the STS balloon with a 6F guiding catheter, all cases were successful. The distal anchoring techniques were attempted in 10 cases, the stent was successfully crossed to the target lesion in all 10 cases. CONCLUSIONS: The novel STS balloon catheter can be safely applied in routine coronary intervention with minimal complications. In addition, this catheter could be useful for performing the kissing balloon technique with a small-caliber guiding catheter and distal anchoring technique with a single guidewire.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad de la Arteria Coronaria , Angioplastia Coronaria con Balón/efectos adversos , Catéteres , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Humanos , Estudios Prospectivos , Stents , Resultado del Tratamiento
4.
Circulation ; 140(23): 1865-1877, 2019 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-31553203

RESUMEN

BACKGROUND: Owing to the differential propensity for bleeding and ischemic events with response to antiplatelet therapy, the safety and effectiveness of potent P2Y12 inhibitor ticagrelor in East Asian populations remain uncertain. METHODS: In this multicenter trial, 800 Korean patients hospitalized for acute coronary syndromes with or without ST elevation and intended for invasive management were randomly assigned to receive, in a 1:1 ratio, ticagrelor (180 mg loading dose, 90 mg twice daily thereafter) or clopidogrel (600 mg loading dose, 75 mg daily thereafter). The primary safety outcome was clinically significant bleeding (a composite of major bleeding or minor bleeding according to PLATO (Platelet Inhibition and Patient Outcomes) criteria at 12 months. RESULTS: At 12 months, the incidence of clinically significant bleeding was significantly higher in the ticagrelor group than in the clopidogrel group (11.7% [45/400] vs 5.3% [21/400]; hazard ratio [HR], 2.26; 95% confidence interval [CI], 1.34 to 3.79; P=0.002). The incidences of major bleeding (7.5% [29/400] vs 4.1% [16/400], P=0.04) and fatal bleeding (1% [4/400] vs 0%, P=0.04) were also higher in the ticagrelor group. The incidence of death from cardiovascular causes, myocardial infarction, or stroke was not significantly different between the ticagrelor group and the clopidogrel group (9.2% [36/400] vs 5.8% [23/400]; HR, 1.62; 95% CI, 0.96 to 2.74; P=0.07). Overall safety and effectiveness findings were similar with the use of several different analytic methods and in multiple subgroups. CONCLUSIONS: In Korean acute coronary syndrome patients intended to receive early invasive management, standard-dose ticagrelor as compared with clopidogrel was associated with a higher incidence of clinically significant bleeding. The numerically higher incidence of ischemic events should be interpreted with caution, given the present trial was underpowered to draw any conclusion regarding efficacy. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02094963.


Asunto(s)
Síndrome Coronario Agudo/tratamiento farmacológico , Clopidogrel/efectos adversos , Hemorragia/inducido químicamente , Inhibidores de Agregación Plaquetaria/efectos adversos , Antagonistas del Receptor Purinérgico P2Y/efectos adversos , Ticagrelor/efectos adversos , Síndrome Coronario Agudo/etnología , Síndrome Coronario Agudo/mortalidad , Síndrome Coronario Agudo/terapia , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Causas de Muerte , Clopidogrel/uso terapéutico , Terapia Combinada , Susceptibilidad a Enfermedades , Femenino , Estudios de Seguimiento , Hemorragia/epidemiología , Hemorragia/mortalidad , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Pacientes Desistentes del Tratamiento , Intervención Coronaria Percutánea , Inhibidores de Agregación Plaquetaria/uso terapéutico , Premedicación , Antagonistas del Receptor Purinérgico P2Y/uso terapéutico , República de Corea/epidemiología , Tamaño de la Muestra , Ticagrelor/uso terapéutico
5.
J Interv Cardiol ; 2020: 2475930, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32733170

RESUMEN

OBJECTIVES: The aim of this study was to assess the clinical impact of 3 bifurcation angles in left main (LM) bifurcation treated with the 2-stent technique. BACKGROUND: Data are limited regarding the impact of bifurcation angles after LM percutaneous coronary intervention (PCI). METHODS: Using patient-level 4 multicenter registries in Korea, 462 patients undergoing LM bifurcation PCI with the 2-stent technique were identified (181 crush, 167 T-stenting; 63% 1st generation drug-eluting stent (DES), 37% 2nd generation DES). Three bifurcation angles, between the LM and left anterior descending (LAD), the LM and left circumflex (LCX), and the LAD and LCX, were measured. The primary outcome was target lesion failure (TLF), a composite of cardiac death, myocardial infarction, and target lesion revascularization (TLR). RESULTS: In patients treated with the crush technique, the best cutoff value (BCV) to predict TLF was 152° of the LM-LAD angle. In the crush group, a significantly higher TLF rate, mostly driven by TLR, was observed in the LM-LAD angle ≥152° group compared with the <152° group (35.7% vs. 14.6%; adjusted hazard ratio 3.476; 95% confidence interval 1.612-7.492). An LM-LAD angle ≥152° was an independent predictor of TLF. In the T-stenting, no bifurcation angle affected the clinical outcomes. CONCLUSIONS: In LM bifurcation PCI using the 2-stent technique, wide LM-LAD angle (≥152°) was associated with a greater risk of TLF in the crush, whereas none of the bifurcation angles affected T-stenting outcomes.


Asunto(s)
Enfermedad de la Arteria Coronaria , Reestenosis Coronaria , Vasos Coronarios , Stents Liberadores de Fármacos/efectos adversos , Infarto del Miocardio , Intervención Coronaria Percutánea , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/cirugía , Reestenosis Coronaria/diagnóstico , Reestenosis Coronaria/etiología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/mortalidad , Evaluación de Procesos y Resultados en Atención de Salud , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/instrumentación , Intervención Coronaria Percutánea/métodos
6.
J Med Internet Res ; 22(8): e18136, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32491988

RESUMEN

BACKGROUND: The Rey-Osterrieth Complex Figure Test (RCFT) is a neuropsychological test that is widely used to assess visual memory and visuoconstructional deficits in patients with cognitive impairment, including Alzheimer disease (AD). Patients with AD have an increased tendency for exhibiting extraordinary behaviors in the RCFT for selecting the drawing area, organizing the figure, and deciding the order of images, among other activities. However, the conventional scoring system based on pen and paper has a limited ability to reflect these detailed behaviors. OBJECTIVE: This study aims to establish a scoring system that addresses not only the spatial arrangement of the finished drawing but also the drawing process of patients with AD by using digital pen data. METHODS: A digital pen and tablet were used to copy complex figures. The stroke patterns and kinetics of normal controls (NCs) and patients with early-onset AD (EOAD) and late-onset AD (LOAD) were analyzed by comparing the pen tip trajectory, spatial arrangement, and similarity of the finished drawings. RESULTS: Patients with AD copied the figure in a more fragmented way with a longer pause than NCs (EOAD: P=.045; LOAD: P=.01). Patients with AD showed an increased tendency to draw the figures closer toward the target image in comparison with the NCs (EOAD: P=.005; LOAD: P=.01) Patients with AD showed the lower accuracy than NCs (EOAD: P=.004; LOAD: P=.002). Patients with EOAD and LOAD showed similar but slightly different drawing behaviors, especially in space use and in the initial stage of drawing. CONCLUSIONS: The digitalized complex figure test evaluated copying performance quantitatively and further elucidated the patients' ongoing process during copying. We believe that this novel approach can be used as a digital biomarker of AD. In addition, the repeatability of the test will delineate the process of executive functions and constructional organization abilities with disease progression.


Asunto(s)
Enfermedad de Alzheimer/epidemiología , Pruebas Neuropsicológicas/normas , Anciano , Análisis de Datos , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Circ J ; 83(7): 1489-1497, 2019 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-31155604

RESUMEN

BACKGROUND: There are limited data on the long-term outcome of platinum chromium-based everolimus-eluting stents (PtCr-EES) vs. cobalt chromium-based zotarolimus-eluting stents (CoCr-ZES).Methods and Results:A total of 3,755 patients undergoing percutaneous coronary intervention (PCI) were randomized 2:1 to PtCr-EES or CoCr-ZES, and 96.0% of patients completed the 3-year clinical follow-up. The primary outcome was target lesion failure (TLF), defined as a composite of cardiac death, target vessel-related myocardial infarction (MI), and clinically-driven target lesion revascularization (TLR). At 3 years, TLF occurred in 5.3% and in 5.4% of the PtCr-EES and CoCr-ZES groups, respectively (hazard ratio 0.978; 95% confidence interval 0.730-1.310, P=0.919). There were no significant differences in the individual components of TLF. Routine angiographic follow-up was performed in 38.9% of the total patients. In a landmark analysis of the subgroup that had follow-up angiography, the clinically-driven TLR rate of CoCr-ZES was significantly higher than PtCr-EES group during the angiography follow-up period (P=0.009). Overall definite and probable stent thrombosis rates were very low in both groups (0.5% vs. 0.6%, P=0.677). CONCLUSIONS: PtCr-EES and CoCr-ZES had similar and excellent long-term outcomes in both efficacy and safety after PCI in an all-comer population.


Asunto(s)
Angiografía Coronaria , Stents Liberadores de Fármacos , Everolimus/administración & dosificación , Intervención Coronaria Percutánea , Sirolimus/análogos & derivados , Anciano , Cromo , Aleaciones de Cromo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Platino (Metal) , Estudios Prospectivos , Falla de Prótesis , Sirolimus/administración & dosificación
8.
Heart Surg Forum ; 20(5): E191-E194, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-29087282

RESUMEN

A 50-year-old woman was referred to our hospital with a chief complaint of chest pain. Coronary angiography revealed a fistula between the left anterior descending artery and pulmonary artery with giant aneurysms. Although coronary angiography is considered the standard tool to confirm a coronary artery fistula, the patient in this case underwent successful surgical repair with the aid of multi-modality imaging.


Asunto(s)
Fístula Arterio-Arterial/diagnóstico , Angiografía por Tomografía Computarizada/métodos , Ecocardiografía Transesofágica/métodos , Tomografía Computarizada Multidetector/métodos , Imagen Multimodal/métodos , Arteria Pulmonar/diagnóstico por imagen , Procedimientos Quirúrgicos Vasculares/métodos , Fístula Arterio-Arterial/complicaciones , Fístula Arterio-Arterial/cirugía , Angiografía Coronaria , Femenino , Humanos , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
9.
J Interv Cardiol ; 29(1): 99-107, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26864953

RESUMEN

BACKGROUND: We used optical coherence tomography (OCT) and intravascular ultrasound (IVUS) to assess the struts of implanted stents in patients with acute coronary syndrome (ACS). METHODS: A totle of 10,756 stent struts were analyzed with OCT in 42 patients of ACS. Of them, both of IVUS and OCT imaging were performed in 33 patients. Appearance of stent struts was classified as well apposed, buried, malapposed, and nondetectable, and the number of stent struts were counted by OCT and IVUS was compared. RESULTS: Most of stent struts were well apposed (78.1%, 8,407/10,756). However, malapposed struts were 5.6% (607/10,756), and 14.1% (1,514/10,756) of stent struts were buried by thrombus. The nondetectable struts were 2.11% (228/10,756) in ACS. 94.7% (216/228) of nondetectable stent struts were associated with red thrombus, and plaque prolapse was in 5.3% (12/228). The number of stent struts counted by OCT were larger than that of IVUS. The mean number of stent struts at the proximal and distal stent edges were 24 ± 6.57 in OCT, the stent struts IVUS counted were 20 ± 4.18 (P < 0.0001). Although the frequency of malapposed struts were similar 4.6% (376/8,248) in OCT versus 4.8% (369/7,674) in IVUS (P = 0.788). Stent struts were often buried by thrombus in ACS 15.2% (1,252/8,248) in OCT versus 9.7% (747/7,674) in IVUS; P = 0.006. The nondetectable struts were fewer in IVUS than OCT 0.2% (16/7,674) in IVUS versus 2.2% (187/8,248) in OCT; P < 0.0001. CONCLUSION: Stent struts are frequently buried and nondetectable due to thrombi burden in ACS patients. Adequate thrombus removal and proper selection of the imaging device is warranted in ACS.


Asunto(s)
Síndrome Coronario Agudo/cirugía , Intervención Coronaria Percutánea/efectos adversos , Complicaciones Posoperatorias/diagnóstico , Stents/efectos adversos , Tomografía de Coherencia Óptica/métodos , Ultrasonografía Intervencional/métodos , Anciano , Investigación sobre la Eficacia Comparativa , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/instrumentación , Intervención Coronaria Percutánea/métodos , Reproducibilidad de los Resultados
10.
J Korean Med Sci ; 31(12): 1929-1936, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27822931

RESUMEN

Data on the clinical outcomes in deferred coronary lesions according to functional severity have been limited. This study evaluated the clinical outcomes of deferred lesions according to fractional flow reserve (FFR) grade using Korean FFR registry data. Among 1,294 patients and 1,628 lesions in Korean FFR registry, 665 patients with 781 deferred lesions were included in this study. All participants were consecutively categorized into 4 groups according to FFR; group 1: ≥ 0.96 (n = 56), group 2: 0.86-0.95 (n = 330), group 3: 0.81-0.85 (n = 170), and group 4: ≤ 0.80 (n = 99). Primary endpoint was major adverse cardiac events (MACE), a composite of all-cause death, myocardial infarction, and target vessel revascularization. The median follow-up period was 2.1 years. During follow-up, the incidence of MACE in groups 1-4 was 1.8%, 7.6%, 8.8%, and 13.1%, respectively. Compared to group 1, the cumulative rate by Kaplan-Meier analysis of MACE was not different for groups 2 and 3. However, group 4 had higher cumulative rate of MACE compared to group 1 (log-rank P = 0.013). In the multivariate Cox hazard models, only FFR (hazard ratio [HR], 0.95; P = 0.005) was independently associated with MACE among all participants. In contrast, previous history of percutaneous coronary intervention (HR, 2.37; P = 0.023) and diagnosis of acute coronary syndrome (ACS) (HR, 2.35; P = 0.015), but not FFR, were independent predictors for MACE in subjects with non-ischemic (FFR ≥ 0.81) deferred coronary lesions. Compared to subjects with ischemic deferred lesions, clinical outcomes in subjects with non-ischemic deferred lesions according to functional severity are favorable. However, longer-term follow-up may be necessary.


Asunto(s)
Enfermedad de la Arteria Coronaria/patología , Reserva del Flujo Fraccional Miocárdico/fisiología , Síndrome Coronario Agudo/complicaciones , Anciano , Causas de Muerte , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Infarto del Miocardio/etiología , Revascularización Miocárdica , Intervención Coronaria Percutánea , Modelos de Riesgos Proporcionales , Sistema de Registros , Índice de Severidad de la Enfermedad
11.
Sci Adv ; 10(18): eadl6409, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701215

RESUMEN

Ultrafast photoinduced melting provides an essential platform for studying nonequilibrium phase transitions by linking the kinetics of electron dynamics to ionic motions. Knowledge of dynamic balance in their energetics is essential to understanding how the ionic reaction is influenced by femtosecond photoexcited electrons with notable time lag depending on reaction mechanisms. Here, by directly imaging fluctuating density distributions and evaluating the ionic pressure and Gibbs free energy from two-temperature molecular dynamics that verified experimental results, we uncovered that transient ionic pressure, triggered by photoexcited electrons, controls the overall melting kinetics. In particular, ultrafast nonequilibrium melting can be described by the reverse nucleation process with voids as nucleation seeds. The strongly driven solid-to-liquid transition of metallic gold is successfully explained by void nucleation facilitated by photoexcited electron-initiated ionic pressure, establishing a solid knowledge base for understanding ultrafast nonequilibrium kinetics.

12.
JACC Cardiovasc Interv ; 17(3): 329-340, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38355261

RESUMEN

BACKGROUND: Distal radial access (DRA) as an alternative access route lacks evidence, despite its recent reputation. OBJECTIVES: The aim of this study was to evaluate the safety and feasibility of DRA on the basis of daily practice. METHODS: The KODRA (Korean Prospective Registry for Evaluating the Safety and Efficacy of Distal Radial Approach) trial was a prospective multicenter registry conducted at 14 hospitals between September 2019 and September 2021. The primary endpoints were the success rates of coronary angiography (CAG) and percutaneous coronary intervention (PCI). The secondary endpoints included successful distal radial artery puncture, access-site crossover, access site-related complications, bleeding events, and predictors of puncture failure. RESULTS: A total of 4,977 among 5,712 screened patients were recruited after the exclusion of 735 patients. The primary endpoints, the success rates of CAG and PCI via DRA, were 100% and 98.8%, respectively, among successful punctures of the distal radial artery (94.4%). Access-site crossover occurred in 333 patients (6.7%). The rates of distal radial artery occlusion and radial artery occlusion by palpation were 0.8% (36 of 4,340) and 0.8% (33 of 4,340) at 1-month follow-up. DRA-related bleeding events were observed in 3.3% of patients, without serious hematoma. Multilevel logistic regression analysis identified weak pulse (OR: 9.994; 95% CI: 7.252-13.774) and DRA experience <100 cases (OR: 2.187; 95% CI: 1.383-3.456) as predictors of puncture failure. CONCLUSIONS: In this large-scale prospective multicenter registry, DRA demonstrated high success rates of CAG and PCI, with a high rate of puncture success but low rates of distal radial artery occlusion, radial artery occlusion, bleeding events, and procedure-related complications. Weak pulse and DRA experience <100 cases were predictors of puncture failure. (Korean Prospective Registry for Evaluating the Safety and Efficacy of Distal Radial Approach [KODRA]; NCT04080700).


Asunto(s)
Arteriopatías Oclusivas , Intervención Coronaria Percutánea , Humanos , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Resultado del Tratamiento , Arteria Radial/diagnóstico por imagen , Angiografía Coronaria/métodos , Hemorragia/etiología , Arteriopatías Oclusivas/complicaciones , Sistema de Registros
13.
Materials (Basel) ; 16(8)2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37110028

RESUMEN

In this study, the characteristics of the SKD61 material used for the stem of an extruder were analyzed through structural analysis, tensile testing, and fatigue testing. The extruder works by pushing a cylindrical billet into a die with a stem to reduce its cross-sectional area and increase its length, and it is currently used to extrude complex and diverse shapes of products in the field of plastic deformation processes. Finite element analysis was used to determine the maximum stress on the stem, which was found to be 1152 MPa, lower than the yield strength of 1325 MPa obtained from tensile testing. Fatigue testing was conducted using the stress-life (S-N) method, considering the characteristics of the stem, and statistical fatigue testing was employed to create an S-N curve. The predicted minimum fatigue life of the stem at room temperature was 424,998 cycles at the location with the highest stress, and the fatigue life decreased with increasing temperature. Overall, this study provides useful information for predicting the fatigue life of extruder stems and improving their durability.

14.
ACS Nano ; 17(22): 22488-22498, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37851941

RESUMEN

Mesoporous nanoparticles provide rich platforms to devise functional materials by customizing the three-dimensional (3D) structures of nanopores. With the pore network as a key tuning parameter, the noninvasive and quantitative characterization of these 3D structures is crucial for the rational design of functional materials. This has prompted researchers to develop versatile nanoprobes with a high penetration power to inspect various specimens sized a few micrometers at nanoscale 3D resolutions. Here, with adaptive phase retrievals on independent data sets with different sampling frequencies, we introduce multidistance coherent X-ray tomography as a noninvasive and quantitative nanoprobe to realize high-resolution 3D imaging of micrometer-sized specimens. The 3D density distribution of an entire mesoporous silica nanoparticle was obtained at 13 nm 3D resolution for quantitative physical and morphological analyses of its 3D pore structure. The morphological features of the whole 3D pore network and pore connectivity were examined to gain insight into the potential functions of the particles. The proposed multidistance tomographic imaging scheme with quantitative structural analyses is expected to advance studies of functional materials by facilitating their structure-based rational design.

15.
Cardiol J ; 30(1): 105-116, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-33634845

RESUMEN

BACKGROUND: The contribution of sex and initial clinical presentation to the long-term outcomes in patients undergoing percutaneous coronary intervention (PCI) is still debated. METHODS: Individual patient data from 5 Korean-multicenter drug-eluting stent (DES) registries (The GRAND-DES) were pooled. A total of 17,286 patients completed 3-year follow-up (5216 women and 12,070 men). The median follow-up duration was 1125 days (interquartile range 1097-1140 days), and the primary endpoint was cardiac death at 3 years. RESULTS: The clinical indication for PCI was stable angina pectoris (SAP) in 36.8%, unstable angina pectoris (UAP) or non-ST-segment elevation myocardial infarction (NSTEMI) in 47.4%, and ST-segment elevation myocardial (STEMI) in 15.8%. In all groups, women were older and had a higher proportion of hypertension and diabetes mellitus compared with men. Women presenting with STEMI were older than women with SAP, with the opposite seen in men. There was no sex difference in cardiac death for SAP or UAP/NSTEMI. In STEMI patients, the incidence of cardiac death (7.9% vs. 4.4%, p = 0.001), all-cause mortality (11.1% vs. 6.9%, p = 0.001), and minor bleeding (2.2% vs. 1.2%, p = 0.043) was significantly higher in women. After multivariable adjustment, cardiac death was lower in women for UAP/NSTEMI (HR 0.69, 95% CI 0.53-0.89, p = 0.005), while it was similar for STEMI (HR 0.97, 95% CI 0.65-1.44, p = 0.884). CONCLUSIONS: There was no sex difference in cardiac death after PCI with DES for SAP and UAP/NSTEMI patients. In STEMI patients, women had worse outcomes compared with men; however, after the adjustment of confounders, female sex was not an independent predictor of mortality.


Asunto(s)
Angina Estable , Stents Liberadores de Fármacos , Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Masculino , Humanos , Femenino , Infarto del Miocardio/etiología , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio con Elevación del ST/cirugía , Intervención Coronaria Percutánea/efectos adversos , Angina Inestable/diagnóstico , Angina Inestable/terapia , Angina Estable/diagnóstico , Angina Estable/terapia , Sistema de Registros , Muerte , Resultado del Tratamiento
16.
J Clin Hypertens (Greenwich) ; 25(9): 828-844, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37584254

RESUMEN

The authors performed this study to investigate the efficacy and safety of a rosuvastatin (RSV)/amlodipine (AML) polypill compared with those of atorvastatin (ATV)/AML polypill. We included 259 patients from 21 institutions in Korea. Patients were randomly assigned to 1 of 3 treatment groups: RSV 10 mg/AML 5 mg, RSV 20 mg/AML 5 mg, or ATV 20 mg /AML 5 mg. The primary endpoint was the efficacy of the RSV 10.20 mg/AML 5 mg via percentage changes in LDL-C after 8 weeks of treatment, compared with the ATV 20 mg /AML 5 mg. There was a significant difference in the mean percentage change of LDL-C at 8 weeks between the RSV 10 mg/AML 5 mg and the ATV 20 mg/AML 5 mg (full analysis set [FAS]: -7.08%, 95% CI: -11.79 to -2.38, p = .0034, per-protocol analysis set [PPS]: -6.97%, 95% CI: -11.76 to -2.19, p = .0046). Also, there was a significant difference in the mean percentage change of LDL-C at 8 weeks between the RSV 20 mg/AML 5 mg and the ATV 20 mg/AML 5 mg (FAS: -10.13%, 95% CI: -15.41 to -4.84, p = .0002, PPS: -10.96%, 95% CI: -15.98 to -5.93, p < .0001). There was no significant difference in the adverse events rates between RSV 10 mg/AML 5 mg, RSV 20 mg/AML 5 mg, and ATV 20 mg/AML 5 mg. In conclusion, while maintaining safety, RSV 10 mg/AML 5 mg and the RSV 20 mg/AML 5 mg more effectively reduced LDL-C compared with the ATV 20 mg /AML 5 mg (Clinical trial: NCT03951207).


Asunto(s)
Dislipidemias , Hipertensión , Leucemia Mieloide Aguda , Humanos , Rosuvastatina Cálcica/efectos adversos , Atorvastatina/efectos adversos , Amlodipino/efectos adversos , Hipertensión/tratamiento farmacológico , Hipertensión/inducido químicamente , LDL-Colesterol , Dislipidemias/tratamiento farmacológico , Leucemia Mieloide Aguda/inducido químicamente , Método Doble Ciego , Resultado del Tratamiento
17.
Clin Cardiol ; 45(4): 391-400, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35170778

RESUMEN

BACKGROUND: Chronic kidney disease (CKD) is a significant comorbidity in patients with heart failure and valvular heart disease. Renal impairment is not well evaluated in the patients with Stage B progressive aortic regurgitation (AR) (mild to moderate and moderate grades in this study), for estimating outcome. HYPOTHESIS: We sought to investigate the prognostic factor, especially CKD, in the patients with progressive AR. METHODS: We enrolled 262 patients with Stage B progressive AR and preserved left ventricular systolic function (ejection fraction ≥ 50%). Based on the presence of CKD, the patients were divided into CKD (n = 70) and non-CKD (n = 192) groups, which CKD was defined as estimated glomerular filtration rate < 60 ml/min/1.73 m2 . The primary outcome was major adverse cardiac events (MACEs), including cardiac death, myocardial infarction, hospitalization for heart failure, and aortic valve replacement. RESULTS: The median follow-up duration was 41.5 (interquartile range: 16.2-71.7) months. Between groups, the CKD patients were older; they had a higher pulse pressure and higher incidence of hypertension, diabetes mellitus, dyslipidemia, cerebrovascular accident, and atrial fibrillation. Compared to the non-CKD group, the CKD group had lower e' velocity (4.36 ± 2.21 vs. 5.20 ± 2.30 cm/s, p = .009), higher right ventricular systolic pressure (38.02 ± 15.79 vs. 33.86 ± 11.77 mmHg, p = .047). The CKD group was associated with increased risk of MACEs (41.4% vs. 22.4%; unadjusted hazard ratio [HR]: 1.78, 95% confidence interval [CI]: 1.11-2.85, p = .017). In multivariate Cox regression analyses, the risk of MACEs was significantly different between groups (adjusted HR: 1.71, 95% CI: 1.11-2.62, p = .015); furthermore, the risk of hospitalization for heart failure (10.0% vs. 2.6%; adjusted HR: 2.30, 95% CI: 1.16-4.55, p = .017) was significantly higher in the CKD group than in the non-CKD group. CONCLUSIONS: In patients with Stage B progressive AR, CKD is an independent prognostic factor for clinical outcomes (composite clinical outcome, hospitalization for heart failure).


Asunto(s)
Insuficiencia de la Válvula Aórtica , Insuficiencia Cardíaca , Insuficiencia Renal Crónica , Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/diagnóstico , Insuficiencia de la Válvula Aórtica/epidemiología , Femenino , Tasa de Filtración Glomerular , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Humanos , Masculino , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Factores de Riesgo
18.
JAMA Cardiol ; 7(4): 418-426, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35262625

RESUMEN

Importance: De-escalation of dual-antiplatelet therapy through dose reduction of prasugrel improved net adverse clinical events after acute coronary syndrome (ACS), mainly through the reduction of bleeding without an increase in ischemic outcomes. However, whether such benefits are similarly observed in those receiving complex procedures is unknown. Objective: To investigate whether the benefits of prasugrel dose de-escalation therapy are maintained in the complex percutaneous coronary intervention (PCI) subgroup. Design, Setting, and Participants: This was a post hoc analysis of the HOST-REDUCE-POLYTECH-ACS trial, a randomized, open-label, adjudicator-blinded, multicenter trial performed at 35 hospitals in South Korea. Study participants included patients with ACS who were receiving PCI. Data were collected from September 30, 2014, to December 18, 2015, and analyzed from September 17, 2020, to June 15, 2021. Interventions and Exposures: Patients were randomized to a prasugrel dose de-escalation (5 mg daily) at 1 month post-PCI group or a conventional (10 mg daily) group. Complex PCI was defined as having at least 1 of the following features: 3 or more stents implanted, 3 or more lesions treated, bifurcation PCI, total stent length 60 mm or larger, left main PCI, or heavy calcification. Main Outcomes and Measures: The main analysis end points were MACE (major adverse cardiac event, a composite of cardiovascular death, nonfatal myocardial infarction, stent thrombosis, and repeat revascularization) at 1 year for ischemic outcomes, and BARC (Bleeding Academic Research Consortium) class 2 or higher bleeding events at 1 year for bleeding outcomes. Results: Of 2271 patients (mean [SD] age, 58.9 [9.0] years; 2024 [89%] male patients) for whom full procedural data were available, 705 patients received complex PCI, and 1566 patients received noncomplex PCI. Complex PCI was associated with higher rates of ischemic outcomes but not with bleeding outcomes. Prasugrel dose de-escalation did not increase the risk of MACE (hazard ratio [HR], 0.88; 95% CI, 0.47-1.66; P = .70 in complex PCI; HR, 0.81; 95% CI, 0.45-1.46; P = .48 in noncomplex PCI; P for interaction = .84) but decreased BARC class 2 or higher bleeding events (HR, 0.25; 95% CI, 0.10-0.61; P = .002 in complex PCI; HR, 0.62; 95% CI, 0.38-1.00; P = .05 in noncomplex PCI; P for interaction = .08), albeit with wide 95% CIs. Conclusions and Relevance: In this post hoc analysis of patients with ACS, prasugrel dose de-escalation compared with conventional therapy was not associated with an increased risk of ischemic outcomes but may reduce the risk of minor bleeding events at 1 year, irrespective of PCI complexity. Trial Registration: ClinicalTrials.gov Identifier: NCT02193971.


Asunto(s)
Síndrome Coronario Agudo , Intervención Coronaria Percutánea , Síndrome Coronario Agudo/tratamiento farmacológico , Síndrome Coronario Agudo/etiología , Terapia Antiplaquetaria Doble , Femenino , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/métodos , Inhibidores de Agregación Plaquetaria , Clorhidrato de Prasugrel
19.
Korean Circ J ; 52(7): 544-555, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35491482

RESUMEN

BACKGROUND AND OBJECTIVES: The outcome benefits of ß-blockers in chronic coronary artery disease (CAD) have not been fully assessed. We evaluated the prognostic impact of ß-blockers on patients with chronic CAD after percutaneous coronary intervention (PCI). METHODS: A total of 3,075 patients with chronic CAD were included from the Grand Drug-Eluting Stent registry. We analyzed ß-blocker prescriptions, including doses and types, in each patient at 3-month intervals from discharge. After propensity score matching, 1,170 pairs of patients (ß-blockers vs. no ß-blockers) were derived. Primary outcome was defined as a composite endpoint of all-cause death and myocardial infarction (MI). We further analyzed the outcome benefits of different doses (low-, medium-, and high-dose) and types (conventional or vasodilating) of ß-blockers. RESULTS: During a median (interquartile range) follow-up of 3.1 (3.0-3.1) years, 134 (5.7%) patients experienced primary outcome. Overall, ß-blockers demonstrated no significant benefit in primary outcome (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.63-1.24), all-cause death (HR, 0.87; 95% CI, 0.60-1.25), and MI (HR, 1.25; 95% CI, 0.49-3.15). In subgroup analysis, ß-blockers were associated with a lower risk of all-cause death in patients with previous MI and/or revascularization (HR, 0.38; 95% CI, 0.14-0.99) (p for interaction=0.045). No significant associations were found for the clinical outcomes with different doses and types of ß-blockers. CONCLUSIONS: Overall, ß-blocker therapy was not associated with better clinical outcomes in patients with chronic CAD undergoing PCI. Limited mortality benefit of ß-blockers may exist for patients with previous MI and/or revascularization. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03507205.

20.
Clin Ther ; 44(10): 1310-1325, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36241463

RESUMEN

PURPOSE: Pitavastatin is a unique lipophilic statin with moderate efficacy in lowering LDL-C levels by 30% to 50% with a tolerable safety profile. However, the efficacy of adding ezetimibe to pitavastatin in patients with dyslipidemia has not been well investigated. Therefore, the objective of this double-blind, multicenter, randomized, Phase III study was to compare the efficacy and safety of pitavastatin and ezetimibe combination therapy with those of pitavastatin monotherapy in Korean patients with primary hypercholesterolemia. METHODS: Korean men and women aged >19 and <80 years with primary hypercholesterolemia requiring medical treatment were included in this study. During the 8-week screening period, all patients were instructed to make therapeutic lifestyle changes. The screening period consisted of a 4-week washout period and a placebo run-in period (4-8 weeks). During treatment period I, patients were randomly assigned to receive 1 of 4 treatments: pitavastatin 2 mg plus ezetimibe 10 mg, pitavastatin 2 mg, pitavastatin 4 mg plus ezetimibe 10 mg, or pitavastatin 4 mg. The 8-week double-blind treatment period then commenced. Adverse events (AEs), clinical laboratory data, and vital signs were assessed in all patients. FINDINGS: The percentages in LDL-C from baseline after 8 weeks of double-blind treatment decreased significantly in the pooled pitavastatin/ezetimibe (-52.8% [11.2%]) and pooled pitavastatin (-37.1% [14.1%]) groups. Treatment with pitavastatin/ezetimibe resulted in a significantly greater LDL-C-lowering effect than that with pitavastatin (difference, -15.8 mg/dL; 95% CI, -18.7 to -12.9; P < 0.001). The precentages of achieving LDL-C goal in pooled pitavastatin/ezetimibe and pooled pitavastatin groups were 94.2% and 69.1%, respectively (P < 0.001). There were no significant differences in the incidence of overall AEs and adverse drug reactions. Serious AEs were comparable between the groups. IMPLICATIONS: Pitavastatin and ezetimibe combinations effectively and safely decreased LDL-C levels by >50% in patients with dyslipidemia. The safety and tolerability of pitavastatin and ezetimibe combination therapy were comparable with those of pitavastatin monotherapy. CLINICALTRIALS: gov identifier: NCT04584736.


Asunto(s)
Anticolesterolemiantes , Dislipidemias , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Hipercolesterolemia , Humanos , Masculino , Femenino , Ezetimiba/efectos adversos , Hipercolesterolemia/tratamiento farmacológico , LDL-Colesterol , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Dislipidemias/diagnóstico , Dislipidemias/tratamiento farmacológico , Método Doble Ciego , Quimioterapia Combinada , Anticolesterolemiantes/efectos adversos , Resultado del Tratamiento
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