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BackgroundComputed tomography (CT)-based fat and muscle measures are associated with outcome in large populations. We tested if muscle and fat characteristics are associated with long-term outcomes after TAVR.MethodsWe included 403 clinical CTs performed prior to TAVR at our center between 2008 and 2016, measuring area (cm2) and density (Hounsfield units, HU) of both psoas muscles (PM), subcutaneous adipose (SAT), and visceral adipose tissue (VAT). Area measures were indexed to height, log-transformed and both area and density were standardized for analysis. We assessed the association of each measure with all-cause mortality (adjusted for age, sex, body mass index (BMI), and the Society of Thoracic Surgeons (STS) risk score.ResultsOf the 403 individuals (83 ± 8 years; 52% female), 167 (41.4%) died during a median follow-up of 458 days (interquartile range IQR 297-840). Fat measures were feasible and rapid. Fat area was available in 242 (60%) patients with an adequate field of view. Individuals with the lowest PM area, SAT area or VAT area exhibited the highest hazard of mortality. In addition, greater SAT density was associated with a higher mortality hazard (adjusted HR per standard deviation increase in density = 1.35, 95%CI 1.10-1.67, P = 0.005).ConclusionRapid CT-based tissue characterization is feasible in patients referred for TAVR. Decreased PM area and increased SAT density are associated with long-term mortality after TAVR, even after accounting for age, sex, BMI, and STS score. Further studies are necessary to interrogate sex-specific relationships between CT tissue metrics and mortality and whether CT measures are incremental to well-established frailty metrics.

Intracranial aneurysms manifest in a vast variety of morphologies and their growth and rupture risk are subject to patient-specific conditions that are coupled with complex, non-linear effects of hemodynamics. Thus, studies that attempt to understand and correlate rupture risk to aneurysm morphology have to incorporate hemodynamics, and at the same time, address a large enough sample size so as to produce reliable statistical correlations. In order to perform accurate hemodynamic simulations for a large number of aneurysm cases, automated methods to convert medical imaging data to simulation-ready configuration withminimal (or no) human intervention are required. In the present study, we develop a highly-automatedmethod based on the immersed boundary method framework to construct computational models from medical imaging data which is the key idea is the direct use of voxelized contrast information from the 3D angiograms to construct a level-set based computational "mask" for the hemodynamic simulation. Appropriate boundary conditions are provided to the mask and the dynamics of blood flow inside the vessels and aneurysm is simulated by solving the Navier-Stokes equations on the Cartesian grid using the sharp-interface immersed boundary method. The present method does not require body conformal surface/volume mesh generation or other intervention for model clean-up. The viability of the proposed method is demonstrated for a number of distinct aneurysms derived from actual, patient-specific data. [ABSTRACT FROM AUTHOR]

Wall shear stress (WSS) has been shown to be associated with myocardial infarction (MI) and progression of atherosclerosis. Wall elasticity is an important feature of hemodynamic modeling affecting WSS calculations. The objective of this study was to investigate the role of wall elasticity on WSS, and justify use of either rigid or elastic models in future studies. Digital anatomic models of the aorta and coronaries were created based on coronary computed tomography angiography (CCTA) in four patients. Hemodynamics was computed in rigid and elastic models using a finite element flow solver. WSS in five timepoints in the cardiac cycle and time averaged wall shear stress (TAWSS) were compared between the models at each 3 mm subsegment and 4 arcs in cross sections along the centerlines of coronaries. In the left main (LM), proximal left anterior descending (LAD), left circumflex (LCX), and proximal right coronary artery (RCA) of the elastic model, the mean percent radial increase 5.95 ± 1.25, 4.02 ± 0.97, 4.08 ± 0.94, and 4.84 ± 1.05%, respectively. WSS at each timepoint in the cardiac cycle had slightly different values; however, when averaged over the cardiac cycle, there were negligible differences between the models. In both the subsegments (n = 704) and subarc analysis, TAWSS in the two models were highly correlated (r = 0.99). In investigation on the effect of coronary wall elasticity on WSS in CCTA-based models, the results of this study show no significant differences in TAWSS justifying using rigid wall models for future larger studies. [ABSTRACT FROM AUTHOR]

Background: Identifying regional wall motion abnormalities (RWMAs) is critical for diagnosing and risk stratifying patients with cardiovascular disease, particularly ischemic heart disease. We hypothesized that a deep neural network could accurately identify patients with regional wall motion abnormalities from a readily available standard 12-lead electrocardiogram (ECG)., Methods: This observational, retrospective study included patients who were treated at Beth Israel Deaconess Medical Center and had an ECG and echocardiogram performed within 14 days of each other between 2008 and 2019. We trained a convolutional neural network to detect the presence of RWMAs, qualitative global right ventricular (RV) hypokinesis, and varying degrees of left ventricular dysfunction (left ventricular ejection fraction [LVEF] ≤50%, LVEF ≤40%, and LVEF ≤35%) identified by echocardiography, using ECG data alone. Patients were randomly split into development (80%) and test sets (20%). Model performance was assessed using area under the receiver operating characteristic curve (AUC). Cox proportional hazard models adjusted for age and sex were performed to estimate the risk of future acute coronary events., Results: The development set consisted of 19,837 patients (mean age 66.7±16.4; 46.7% female) and the test set comprised of 4,953 patients (mean age 67.5±15.8 years; 46.5% female). On the test dataset, the model accurately identified the presence of RWMA, RV hypokinesis, LVEF ≤50%, LVEF ≤40%, and LVEF ≤35% with AUCs of 0.87 (95% CI 0.858-0.882), 0.888 (95% CI 0.878-0.899), 0.923 (95% CI 0.914-0.933), 0.93 (95% CI 0.921-0.939), and 0.876 (95% CI 0.858-0.896), respectively. Among patients with normal biventricular function at the time of the index ECG, those classified as having RMWA by the model were 3 times the risk (age- and sex-adjusted hazard ratio, 2.8; 95% CI 1.9-3.9) for future acute coronary events compared to those classified as negative., Conclusions: We demonstrate that a deep neural network can help identify regional wall motion abnormalities and reduced LV function from a 12-lead ECG and could potentially be used as a screening tool for triaging patients who need either initial or repeat echocardiographic imaging.

Objective: Skeletal muscle quality and mass are important for maintaining physical function during advancing age. We leveraged baseline data from Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE) to evaluate whether paraspinal muscle density and muscle area are associated with cardiac or physical function outcomes in people with HIV (PWH)., Methods: REPRIEVE is a double-blind randomized trial evaluating the effect of pitavastatin for primary prevention of major adverse cardiovascular events in PWH. This cross-sectional analysis focuses on participants who underwent coronary computed tomography at baseline. Lower thoracic paraspinal muscle density (Hounsfield units [HU]) and area (cm 2 ) were assessed on noncontrast computed tomography., Results: Of 805 PWH, 708 had paraspinal muscle measurements. The median age was 51 years and 17% were natal female patients. The median muscle density was 41 HU (male) and 30 HU (female); area 13.2 cm 2 /m (male) and 9.9 cm 2 /m (female). In adjusted analyses, greater density (less fat) was associated with a lower prevalence of any coronary artery plaque, coronary artery calcium score >0, and high plaque burden ( P = 0.06); area was not associated with plaque measures. Among 139 patients with physical function measures, greater area (but not density) was associated with better performance on a short physical performance battery and grip strength., Conclusions: Among PWH, greater paraspinal muscle density was associated with a lower prevalence of coronary artery disease while greater area was associated with better physical performance. Whether changes in density or area are associated with changes in CAD or physical performance will be evaluated through longitudinal analyses in REPRIEVE., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background:  Rapid improvement of scanner and postprocessing technology as well as the introduction of minimally invasive procedures requiring preoperative imaging have led to the broad utilization of cardiac computed tomography (CT) beyond coronary CT angiography (CTA)., Method:  This review article presents an overview of recent literature on cardiac CT. The goal is to summarize the current guidelines on performing cardiac CT and to list established as well as emerging techniques with a special focus on extracoronary applications., Results and Conclusion:  Most recent guidelines for the appropriate use of cardiac CT include the evaluation of coronary artery disease, cardiac morphology, intra- and extracardiac structures, and functional and structural assessment of the myocardium under certain conditions. Besides coronary CTA, novel applications such as the calculation of a CT-derived fractional flow reserve (CT-FFR), assessment of myocardial function and perfusion imaging, as well as pre-interventional planning in valvular heart disease or prior pulmonary vein ablation in atrial fibrillation are becoming increasingly important. Especially these extracoronary applications are of growing interest in the field of cardiac CT and are expected to be gradually implemented in the daily clinical routine., Key Points:   · Coronary artery imaging remains the main indication for cardiac CT. · Novel computational fluid dynamics allow the calculation of a CT-derived fractional flow reserve in patients with known or suspected coronary artery disease. · Cardiac CT delivers information on left ventricular volume as well as myocardial function and perfusion. · CT is the cardinal element for pre-interventional planning in transcatheter valve implantation and pulmonary vein isolation., Citation Format: · Taron J, Foldyna B, Eslami P et al. Cardiac Computed Tomography - More Than Coronary Arteries? A Clinical Update. Fortschr Röntgenstr 2019; 191: 817 - 826., Competing Interests: Prof. Dr. Fabian Bamberg: Bayer Healthcare, speakers bureau and unrestricted research grant Siemens Healthineers, speakers bureau and unrestricted research grant.Prof. Dr. Udo Hoffmann: Research support on behalf of the institution: KOWA, MedImmune, HeartFlow, Duke University (Abbott), Oregon Health & Science University (AHA, 13FTF16450001), Columbia University (NIH, 5R01-HL109711), NIH/NHLBI 5K24HL113128, NIH/NHLBI 5T32HL076136, NIH/NHLBI 5U01HL123339 Consulting Fees from: Abbott, Duke University (NIH), Recor Medical., (© Georg Thieme Verlag KG Stuttgart · New York.)