Aims: To identify changes in multidirectional strain and strain rate (SR) in patients with aortic stenosis (AS).
Methods And Results: A total of 420 patients (age 66.1 ± 14.5 years, 60.7% men) with aortic sclerosis, mild, moderate, and severe AS with preserved left ventricular (LV) ejection fraction [(EF), ≥50%] were included. Multidirectional strain and SR imaging were performed by two-dimensional speckle tracking. Patients were more likely to be older (P < 0.001) and at a worse New York Heart Association functional class (P < 0.001) with increasing AS severity. There was a progressive stepwise impairment in longitudinal, circumferential, and radial strain and SR with increasing AS severity (all P < 0.001). The myocardial dysfunction appeared to start in the subendocardium with mild AS, to mid-wall dysfunction with moderate AS, and eventually transmural dysfunction with severe AS. Aortic valve area, as a measure of AS severity, was an independent determinant of multidirectional strain and SR on multiple linear regressions.
Conclusions: Patients with AS have evidence of subclinical myocardial dysfunction early in the disease process despite normal LVEF. The myocardial dysfunction appeared to start in the subendocardium and progressed to transmural dysfunction with increasing AS severity. Symptomatic moderate and severe AS patients had more impaired multidirectional myocardial functions compared with asymptomatic patients.
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http://dx.doi.org/10.1093/eurheartj/ehr084 | DOI Listing |
Mater Horiz
January 2025
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang province, 315201, China.
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January 2025
State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, PR China. Electronic address:
Multidirectional strain sensors are of technological importance for wearable devices and soft robots. Here, we report that flexible materials capable of multidirectional anisotropic strain sensing can be constructed leveraging diffusion-induced infiltration of monomers and in situ polymerization of metal ion-containing double network hydrogels in and on the surface of micro-corrugated chiral nematic cellulose nanocrystal/glucose films. Integrating the micro-corrugated cellulose nanocrystal/glucose chiral nematic films with ionic conductive hydrogels of PAA-co-AAm/sodium alginate/Al endows the materials with multidirectional mechanoelectrical resistivity and mechanochromism anisotropy.
View Article and Find Full Text PDFSci Rep
November 2024
Department of Orthopaedics, General Hospital of Ningxia Medical University, Yinchuan City of Ningxia, China.
Oblique lateral interbody fusion (OLIF) is a minimally invasive surgery for the treatment of lumbar degenerative diseases (LDD). Under normal bone mass(NB), supplemental with lateral plate (LP) fixation has been proven to provide stability and reduce complications. However, it is unclear whether OLIF combined with LP fixation can achieve satisfactory fixation effects in cases of osteoporosis(OP) or osteopenia (OS)? In this study, Eighteen L3-5 spinal specimens from 3 to 6 months old fresh calves were equally divided into 3 groups: group A (NB), group B (OS) and group C (OP).
View Article and Find Full Text PDFMaterials (Basel)
October 2024
School of Aerospace Engineering, North University of China, Taiyuan 030051, China.
This study investigates the preparation of ultrahigh-strength AZ80 magnesium alloy bulks using room temperature multidirectional forging (MDF) at different strain rates. The focus is on elucidating the effects of multidirectional loading and strain rates on grain refinement and the subsequent impact on the mechanical properties of the AZ80 alloy. Unlike hot deformation, the alloy subjected to room temperature MDF exhibits a lamellar twinned structure with multi-scale interactions.
View Article and Find Full Text PDFSensors (Basel)
September 2024
State Key Laboratory of Mechanics and Control for Aerospace Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Embedded fiber Bragg gratings are increasingly applied for in-situ strain measurement in fiber-reinforced plastics, integral to high-end aerospace equipment. Existing research primarily focuses on in-plane strain measurement, limited by the fact that fiber Bragg gratings are mainly sensitive to axial strain. However, out-of-plane strain measurement is equally important for comprehending structural deformation.
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