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The motion of binary particles in three horizontal rotating drums with continuous rotational speed changes was studied based on the Discrete Element Method (DEM). Different simulation conditions were compared between two circular drums and an elliptical drum using the same number of physical properties for binary particles and drums, rotating at a speed series from 0.01 to 21.9 rad/s. By varying the rotational speed, four flow regimes were produced in the simulation. Flow regimes, velocity vectors, normal forces, and the number of contacts between 1 mm particles and 3 mm particles were comparatively analyzed, especially the particle velocity at transient changing rotational speeds. The results showed that four flow regimes were found at the same rotational speed for three different rotating drums, and normal forces were weakest for the cataracting regime; moreover, the three layers of particles were damaged when the rotational speed was suddenly decreased and the velocity direction of the particle motion was changed at the top of the particles' bed. The maximum number of contacts was found with the rolling regime, based on the simulation results. The number of contacts of the major axis circular drum was smaller than for the minor axis at the same rotational speed, and the number of contacts of the elliptical drum was the largest among the three rotating drums. [ABSTRACT FROM AUTHOR]

Background: Myocardial bridging (MB) is commonly treated in patients with hypertrophic cardiomyopathy. However, whether and how MB should be treated in patients with hypertrophic obstructive cardiomyopathy (HOCM) who underwent septal myectomy remain unclear. Methods: A total of 823 adults with HOCM who underwent septal myectomy at the Fuwai Hospital from 2011 to 2017 were retrospectively studied. Results: Overall, 31 events occurred: 24 patients died and 7 had nonfatal myocardial infarction (MI). The 3‐year cumulative event‐free survival of all‐cause death (97.9% vs. 100% vs. 100% vs. 98.4%, p =.89) and cardiovascular death (98.3% vs. 100% vs. 100% vs. 98.4%, p =.63) were similar among the four groups (non‐MB, coronary artery bypass grafting [CABG], unroofing, untreated, respectively). However, the 3‐year cumulative event‐free survival of nonfatal MI (100% vs. 97.5% vs. 98.0% vs. 89.9%, p <.001) and combined endpoints (97.9% vs. 97.5% vs. 98.0% vs. 88.4%, p =.02) were significantly lowest in untreated MB (non‐MB, CABG, unroofing, untreated, respectively). Cox regression analysis indicated that untreated MB was a significant independent predictor of combined endpoints (hazard ratio: 4.06, 95% confidence interval: 1.60–10.32, p <.001). Moreover, 49 patients underwent coronary artery computed tomography 1 year after surgery. The patency rate of the saphenous vein graft was significantly higher than that of the left internal mammary artery (13.3% vs. 84.2%, p <.001). No MB was detected in the unroofing group. Conclusions: Surgical MB treatment could be beneficial and performed safely during septal myectomy. Myocardial unroofing is the recommended treatment for MB, and unroofing when technically possible may be preferable for long‐term outcomes. [ABSTRACT FROM AUTHOR]

Background and Objectives: The relationship between physical frailty, age-related conditions, and the incidence of degenerative valvular heart disease (VHD) remains unclear. This study aimed to investigate the potential association between physical frailty and the development of degenerative VHD., Research Design and Methods: Participants from the UK Biobank who were initially free of VHD and heart failure were categorized into 3 groups based on the frailty phenotype: non-frailty, pre-frailty, and frailty. The frailty phenotype was determined by evaluating the following 5 components: weight loss, exhaustion, reduced physical activity, slow gait speed, and low grip strength. The incidence of degenerative VHD, including mitral valve regurgitation (MR), aortic valve regurgitation (AR), and aortic valve stenosis (AS), was assessed using hospital admission or death registries., Results: Among the 331 642 participants, 11 885 (3.6%) exhibited frailty and 143 379 (43.2%) were categorized as pre-frailty. During a median follow-up of 13.8 years, there were 3 684 MR, 1 205 AR, and 3 166 AS events. Compared to non-frailty participants, those with pre-frailty and frailty showed significantly increased risks for MR (hazard ratio [HR], HR pre-frailty :1.19, 95% confidence interval [CI]: 1.11-1.28; HR frailty : 1.50, 95% CI: 1.30-1.74), AR (HR pre-frailty :1.19, 95% CI: 1.05-1.34; HR frailty : 1.58, 95% CI: 1.22-2.04), and AS (HR pre-frailty :1.19, 95% CI: 1.11-1.29; HR frailty : 1.74, 95% CI: 1.51-2.00). Among the 5 components, slow gait speed showed the strongest association with the risk of various types of VHD (HR MR : 1.50, 95% CI: 1.34-1.65; HR AR : 1.50, 95% CI: 1.24-1.80; HR AS : 1.46, 95% CI: 1.32-1.62), followed by exhaustion, low grip strength, and weight loss., Discussion and Implications: Pre-frailty and frailty were associated with a higher risk of all 3 types of degenerative VHD. Early detection and intervention for pre-frailty and frailty in middle-aged and older individuals may assist in preventing or delaying the onset of degenerative VHD., Competing Interests: All authors declare no conflict of interest. The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Gerontological Society of America.)

Objective: To assess the value of detecting the compositional features of carotid atherosclerotic plaques by 3.0T high resolution magnetic resonance imaging (MRI) in patients with coronary artery disease (CAD)., Methods: Consecutive 104 patients with coronary atherosclerosis confirmed by coronary angiography were prospectively recruited from January 2013 to January 2015 in Tiantan hospital. All patients were imaged with 3.0T high resolution MRI system. After exclusion patients with poor image quality, 97 patients were divided into 3 groups according to the degree of coronary artery stenosis: coronary atherosclerosis group (coronary stenosis between 1%-49%, n=16); single-vessel lesion group (single vessel lesion with stenosis between 50%-100%, n=48); multi-vessel lesion group (two or three vessel lesions with stenosis between 50%-100% or left main stem disease, n=33). The prevalence of total carotid plaque, calcified plaque, lipid-rich necrotic core, intra-plaque hemorrhage, plaque ulcer and rupture were compared among 3 groups., Results: The prevalence of total carotid plaque (81.3%(13/16), 72.9%(35/48), and 93.9%(31/33)) and calcified plaque (50.0%(8/16), 35.4%(17/48), and 42.4%(14/33)) were similar among the 3 groups (both P>0.05). The prevalence of carotid lipid-rich necrotic core in coronary atherosclerosis group was significantly lower than in single-vessel lesion group (18.8%(3/16) vs. 64.6%(31/48), P<0.01) and multi-vessel lesion group(18.8%(3/16) vs. 69.7%(23/33), P<0.01), but there was no significant difference between single-vessel lesion group and multi-vessel lesion group(P>0.05). Intra-plaque hemorrhage was detected in 2 patients of multi-vessel lesion group. There was no plaque ulcer or rupture in this cohort., Conclusion: Carotid plaque features are associated with the severity of coronary atherosclerosis in CAD patients.