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Abstract Background There is a paucity of literature regarding outcomes of patients with mitral valve prolapse (MVP) and mitral annular disjunction (MAD) after mitral surgery, with many unanswered questions including the post-surgical persistence of MAD, effect of MAD on mitral valve reparability, and incidence of arrhythmia after mitral valve surgery. We aimed to examine the prevalence, imaging characteristics and clinical associations of mitral annular disjunction among patients undergoing mitral valve surgery for mitral valve prolapse, as well as outcomes after surgery including the persistence of MAD, arrhythmic events and excess mortality. Results A retrospective analysis of 111 consecutive patients who underwent mitral valve surgery for MVP was performed. A total of 32 patients (28.8%) had MAD. Patients with MAD were younger (64 vs 67 yrs, p = 0.04), with lower rates of hypertension (21.9% vs 50.6%, p = 0.01) and hyperlipidaemia (25% vs 50.6%; p = 0.01) and were more likely to be female (43.8% vs 21.4%, p = 0.04) with myxomatous leaflets > 5mm (90.6% vs 15.2%, p =

PurposeIn this cohort study, 5-year data from the Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter Registry (ie, CONFIRM) were examined to identify associations of baseline aspirin and statin use with mortality, major adverse cardiovascular events (MACE), and myocardial infarction (MI) in individuals without substantial (≥50%) stenosis.Materials and methodsIn this prospective cohort study, all participants in the registry underwent coronary CT angiography and were classified as having no detectable coronary plaque or having nonobstructive coronary artery disease (CAD) (1%-49% stenosis). Participants with obstructive (≥50%) stenosis were excluded from analysis. The study commenced in June 2003 and was completed in March 2016. All unadjusted and risk-adjusted analyses utilized the Cox proportional hazard model with hospital sites modeled using shared frailty.ResultsA total of 6386 participants with no detectable plaque or with nonobstructive CAD were included (mean age, 56.0 years ± 13.3 [SD], 52% men). The mean follow-up period was 5.66 years ± 1.10. Nonobstructive CAD (n = 2815, 44% of all participants included in the study) was associated with a greater risk of all-cause mortality (10.6% [298 of 2815] vs 4.8% [170 of 3571], P < .001) compared to those without CAD (n = 3571, 56%). Baseline aspirin and statin use was documented for 1415 and 1429 participants, respectively, with nonobstructive CAD, and for 1560 and 1565 participants without detectable plaque, respectively. In individuals with nonobstructive CAD, baseline aspirin use was not associated with a reduction in MACE (10.9% [102 of 936] vs 14.7% [52 of 355], P = .06), all-cause mortality (9.6% [95 of 991] vs 10.9% [46 of 424], P = .468), or MI (4.4% [41 of 936] vs 6.2% [22 of 355], P = .18). On multivariate risk-adjusted analysis, baseline statin use was associated with a lower rate of MACE (hazard ratio, 0.59; 95% CI: 0.40, 0.87; P = .007). Neither therapy improved clinical outcomes for participants with no detectable plaque.ConclusionIn participants with nonobstructive CAD, baseline use of statins, but not of aspirin, was associated with improved clinical outcomes. Neither therapy was associated with benefit in participants without plaque.Keywords: Aspirin, Statin, Coronary Artery Disease, CT Angiography, Nonobstructive Coronary Artery DiseaseClinical trial registration no. NCT01443637 Supplemental material is available for this article. © RSNA, 2022See also the commentary by Canan and Navar in this issue.

Past studies have shown that shallow subgrade soil can transform to a slurry (i.e., fluidization) under unfavourable cyclic loading. However, the depth-dependent behaviour of soil parameters during this process has not been properly understood. The current study utilised a large-scale cylindrical test rig, where instrumentation was installed to observe the soil behaviour along the depth of the test specimens under cyclic loading, to examine and quantify the onset of soil fluidization. The results show that excess pore water pressure tends to rise more at the upper layers causing zero-effective stress, while void ratio expands rapidly within the deteriorated soil fabric, making the water content approach the liquid limit of soil when internal moisture migration occurs from the bottom to the top of the specimen. The larger the cyclic load, the deeper the fluidized zone and the faster the fluidization. The study also suggests that the zero-effective stress condition alone cannot interpret the inception of soil fluidization; hence, the change in void ratio and the liquidity index during the application of cyclic loading should also be considered in tandem. Key words: consolidation, excess pore pressures, soil fluidization, cyclic loading, fabric/structure of soils, 1. Introduction Subjected to unfavourable cyclic loading induced by heavy haul trains, surface soil layer tends to degrade considerably with increasing excess pore water pressure (EPWP) to initiate fluidization (Duong [...]

Abstract The guidelines released by the American College of Cardiology/American Heart Association/Heart Failure Society of America (ACC/AHA/HFSA) in 2022 and those released in 2021 by the European Society of Cardiology (ESC) play a crucial role in offering evidence-based recommendations for the diagnosis and management of heart failure (HF). This comprehensive review aims to provide an overview of these guidelines, incorporating insights from relevant clinical trials. While there is considerable alignment between the two sets of guidelines, certain notable differences arise due to variations in publication timelines, which we will outline. By presenting this summary, our objective is to empower clinicians to make informed decisions regarding HF management in their own practice, and facilitate the development of more harmonized guidelines in the future.

This study demonstrates the change in porosity of permeable reactive barrier (PRB) material when it reacts with acidic flow. The laboratory column test data obtained over 9 months prove that the porosity of a granular limestone assembly decreases significantly due to bio-geochemical clogging caused by a continuous flow of acidic groundwater. The variations in pH, the pressure measurements, ion concentrations, and the results from X-ray diffraction suggest that clogging at the outlet of the column is much less than at the inlet. About 57% of the total reduction in porosity of the column is attributed to chemical clogging, while the remainder is mainly due to biological clogging. In this paper, a mathematical approach is proposed to estimate the reduction of reactive surface area based on changes in the pore volume. These proposed equations suggest that at the end of experimentation, the dissolution of calcite and bio-geochemical clogging can reduce the total surface area of limestone aggregates by more than 70%. The rigorous approach presented in this paper to determine the dominant clogging component within a granular filter at a given time is vital in estimating the longevity of a PRB and for planning its maintenance. Key words: acidic groundwater, permeable reactive barrier, biogeochemical clogging, porosity, surface area, 1. Introduction Biological and chemical clogging reduces the porosity of granular filters, obstructs the flow, and increases the hydraulic gradients in porous media (Cooke et al. 2005; McIsaac and Rowe [...]

Recent investigations have shown that under adverse cyclic triaxial loading, the upper part of soil specimens can turn into a fluid-like state with increased water content (i.e., fluidization), whereas the lower layers can maintain a relatively high stiffness. This paper aims to gain further insight into this behaviour by monitoring the development in excess pore water pressure (EPWP) at the top and bottom of the test specimens, followed by post- analysis of water content distribution along the specimen. The results show that the EPWP at the uppermost part of the specimen develops rapidly and approaches the zeroeffective stress level, whereas the EPWP at the bottom part of the specimen tends to stabilize while undergoing densification. Accompanied with this process is a redistribution of the water content along the specimen height where the water content at the upper soil layer increases to approach the liquid limit while increasing the void ratio. Key words: railways, excess pore water pressures, cyclic loading, soil fluidization, mud pumping Des etudes recentes ont montre que sous une charge triaxiale cyclique defavorable, la partie superieure des echantillons de sol peut se transformer en un etat fluide avec une teneur en eau accrue (c'est- a-dire une fluidisation), tandis que les couches inferieures peuvent maintenir une rigidite relativement elevee. L'article actuel vise a mieux comprendre ce comportement en surveillant l'evolution de la surpression d'eau interstitielle (EPWP) en haut et en bas des specimens d'essai, puis en analysant la distribution de la teneur en eau le long du specimen. Les resultats montrent que la PEMP dans la partie superieure de l'eprouvette se developpe rapidement et s'approche du niveau de contrainte effective nulle, tandis que la PEMP dans la partie inferieure de l'eprouvette tend a se stabiliser tout en subissant une densification. Ce processus s'accompagne d'une redistribution de la teneur en eau le long de la hauteur de l'echantillon, ou la teneur en eau de la couche superieure du sol augmente pour se rapprocher de la limite de liquidite tout en augmentant le taux de vide. [Traduit par la Redaction] Mots-cles : chemins de fer, pressions excessives de l'eau interstitielle, charge cyclique, fluidification du sol, pompage de boue, Introduction Low-to-medium-plasticity soils can transform to a slurry under adverse cyclic loading induced by the passage of trains (e.g., mud pumping and slurry holes), as shown in recent studies (Duong [...]

For the development of a high-speed rail network in urbanised areas, ground vibration and associated damage to surrounding structures are major concerns. The problem becomes critical especially in areas with soft soil deposits due to amplification of vibration during Rayleigh wave propagation. In the present study, near field ground vibrations from a high-speed rail ballasted track are predicted for an area which contains predominantly soft marine clay deposits. A two-dimensional finite element model coupled with infinite boundaries is developed in ABAQUS. Using the finite element model, the vibration in terms of peak particle velocity (PPV) and root mean square (RMS) velocity is determined for different train speeds and soil profiles, at varying distances from the track centre. Different soil profiles are considered in this study by varying the thickness and depth of the soft clay layer. From the results, it was observed that maximum ground vibration happens when the train speed is close to the Rayleigh velocity of the soft clay layer. Further, the safe limits for residential and sensitive structures are determined for different conditions based on peak particle velocity. Considering human discomfort during vibration propagation, the vibration level in decibel scale is determined for different track configurations.