Search

BACKGROUND: A recent study reported that the outcome of patients with plaque erosion treated with stenting is poor when the underlying plaque is lipid rich. However, the detailed phenotype of patients with plaque erosion, particularly as related to different age groups, has not been systematically studied. METHODS AND RESULTS: Patients with acute coronary syndromes caused by plaque erosion were selected from 2 data sets. Demographic, clinical, angiographic, and optical coherence tomography findings of the culprit lesion were compared between 5 age groups. Among 579 erosion patients, male sex and current smoking were less frequent, and hypertension, diabetes, and chronic kidney disease were more frequent in older patients. ST-segment–elevation myocardial infarction was more frequent in younger patients. Percentage of diameter stenosis on angiogram was greater in older patients. The prevalence of lipid-rich plaque (27.3% in age <45 years and 49.4% in age ≥75 years, P<0.001), cholesterol crystal (3.9% in age <45 years and 21.8% in age ≥75 years, P=0.027), and calcification (5.5% in age <45 years and 54.0% in age ≥75 years, P<0.001) increased with age. After adjusting risk factors, younger patients were associated with the presence of thrombus, and older patients were associated with greater percentage of diameter stenosis and the presence of lipid-rich plaque and calcification. CONCLUSIONS: The demographic, clinical, angiographic, and plaque phenotypes of patients with plaque erosion distinctly vary depending on age. This may affect the clinical outcome in these patients. REGISTRATION: URL: https://www.clini​caltr​ials.gov. Unique identifiers: NCT03479723, NCT02041650.

Antiplatelet agents and statin therapies are widely used in patients with known cardiovascular disease. Plaque rupture (PR) and plaque erosion (PE) are the most frequent underlying mechanisms of acute coronary syndromes (ACS). The conditions and medications that are associated with ST-segment elevation myocardial infarction (STEMI) following PR or PE have not been systematically studied. A total of 838 ACS patients (494 with STEMI, 344 with NSTE-ACS) who were diagnosed with PR or PE by optical coherence tomography were included. The patients were categorized into two groups based on underlying pathology, and the baseline characteristics and culprit plaque morphology associated with STEMI were investigated within each group. Among 838 patients, 467 (55.7%) had PR, and 371 (44.3%) were diagnosed with PE. Among patients with PR, older age, hyperlipidemia, no antiplatelet therapy, higher level of low-density lipoprotein cholesterol, and greater lipid burden and macrophage infiltration were associated with increased probability of STEMI. Among patients with PE, no dual antiplatelet therapy and no statin therapy were associated with increased probability of STEMI. The incidence of STEMI caused by PR was significantly lower on antiplatelet therapy (P < 0.001), and the incidence of STEMI caused by PE was significantly lower on antiplatelet therapy (P < 0.001) or on statin therapy (P < 0.001). Antiplatelet therapy is associated with lower probability of STEMI, regardless of underlying pathology, and statin therapy is associated with lower probability of STEMI in PE as clinical presentation of ACS. Graphic Abstract: Statin therapy prior to the onset of acute coronary syndromes (ACS) may reduce the probability of plaque rupture. Antiplatelet therapy prior to the onset of ACS is associated with reduced probability of ST-segment elevation myocardial infarction (STEMI) following both plaque rupture and plaque erosion, and dual antiplatelet therapy offers additi

Synchrotron‐based full‐field tomographic microscopy established itself as a tool for noninvasive investigations. Many beamlines worldwide routinely achieve micrometer spatial resolution while the isotropic 100‐nm barrier is reached and trespassed only by few instruments, mainly in the soft x‐ray regime. We present an x‐ray, full‐field microscope with tomographic capabilities operating at 10 keV and with a 3D isotropic resolution of 144 nm recently installed at the TOMCAT beamline of the Swiss Light Source. Custom optical components, including a beam‐shaping condenser and phase‐shifting dot arrays, were used to obtain an ideal, aperture‐matched sample illumination and very sensitive phase‐contrast imaging. The instrument has been successfully used for the nondestructive, volumetric investigation of single, unstained cells.

During its first four years of life, the TOMCAT beamline [1] at the Swiss Light Source has established itself as a state‐of‐the art hard x‐ray tomographic microscopy endstation for experiments on a large variety of samples, ranging from the fields of biology to materials science. It routinely performs absorption as well as phase‐contrast imaging with an isotropic voxel size ranging from 0.360 up to 14.8 microns. Phase contrast is obtained either with simple edge‐enhancement, a modified transport of intensity approach [2] or grating interferometry [3]. Typical acquisition times are on the order of a few minutes, depending on energy and resolution. A recently implemented automatic sample exchanger is now available for high‐throughput studies [4]. In addition to further developments in phase‐contrast imaging, current scientific activities at the beamline focus on pushing spatial and temporal resolution by a few orders of magnitude, aiming at nano‐ [5] and “real‐time” [6] tomography.

Despite the exposure of the entire vasculature to the atherogenic effects of systemic risk factors, atherosclerotic plaques preferentially develop at sites with disturbed flow. This study aimed at exploring in vivo the relationship between local endothelial shear stress (ESS) and coronary plaque characteristics in humans, using computational fluid dynamics and frequency-domain optical coherence tomography (FD-OCT).

Recent studies described different clinical and underlying plaque characteristics between patients with and without plaque rupture presenting with acute coronary syndrome (ACS). In light of the systemic nature of atherosclerosis, we hypothesized that nonculprit plaques might also express different morphological features in these 2 groups of patients.

X-ray tomography can provide structural information of whole cells in close to their native state. Radiation-induced damage, however, imposes a practical limit to image resolution, and as such, a choice between damage, image contrast, and image resolution must be made. New coherent diffractive imaging techniques, such Fresnel Coherent Diffractive Imaging (FCDI), allows quantitative phase information with exceptional dose efficiency, high contrast, and nano-scale resolution. Here we present three-dimensional quantitative images of a whole eukaryotic cell by FCDI at a spatial resolution below 70 nm with sufficient phase contrast to distinguish major cellular components. From our data, we estimate that the minimum dose required for a similar resolution is close to that predicted by the Rose criterion, considerably below accepted estimates of the maximum dose a frozen-hydrated cell can tolerate. Based on the dose efficiency, contrast, and resolution achieved, we expect this technique will find immediate applications in tomographic cellular characterisation.

n/a