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Background: People living with HIV have an increased risk of cardiovascular disease (CVD). Although coronary endothelial function (CEF) is an early direct indicator of CVD, only a few studies have been able to interrogate CEF directly. Most studies have examined vascular endothelial function through indirect assessment of brachial flow‐mediated dilatation (FMD). However, peripheral arteries are significantly larger and manifest atherogenesis differently from the coronary arteries, and so produce conflicting results. Additionally, none of these studies focused on young adults who acquired HIV perinatally or in early childhood. Objective: The present study investigates CEF in a unique population of young adults with lifelong HIV using direct magnetic resonance imaging (MRI) of coronary FMD (corFMD) with an in‐house developed MRI‐integrated isometric handgrip exercise system with continuous feedback and monitoring mechanisms (fmIHE). Methods: Young adults who acquired HIV perinatally or in early childhood (n = 23) and group‐matched healthy participants (n = 12) completed corFMD‐MRI with fmIHE. CorFMD was measured as the coronary cross‐sectional area response to the fmIHE. Results: In univariable and multivariable regression analysis, HIV status was a significant risk modifier. CD8+ T‐cell count and smoking pack‐years and their interaction with HIV status were independently associated with impaired coronary artery response to fmIHE. In people living with HIV, corFMD was significantly inversely correlated with CD8+ T‐cells and smoking pack‐years. In a multivariable regression analysis adjusted for age and body mass index, CD8+ T‐cells and smoking and their interaction with HIV status remained significant independent predictors of coronary endothelial dysfunction. Discussion: In this unique population of young adults, HIV status was a significant risk modifier, and immune activation and smoking were associated with decreased CEF, directly measured from the coronary vascular response to fmIHE. Conclusions: Management of CVD risk factors such as smoking and developing strategies that target immune activation in people living with HIV are warranted. [ABSTRACT FROM AUTHOR]

Abstract: Four different techniques for 3-T whole-heart coronary magnetic resonance angiography (MRA) using free-breathing three-dimensional segmented parallel imaging and adiabatic T2-preparation were assessed. Coronary MRA at 3 T is improved by shortening the acquisition window more than employing the highest spatial resolution. Double-oblique whole-heart acquisitions result in better overall image quality and allow for better delineation of the left anterior descending coronary artery. It is possible to attain shorter acquisition windows and a smaller voxel size at 3 T than previously reported at 1.5 T. [Copyright &y& Elsevier]

It is now recognized that prediction of the vulnerable coronary plaque rupture requires not only an accurate quantification of fibrous cap thickness and necrotic core morphology but also a precise knowledge of the mechanical properties of plaque components. Indeed, such knowledge would allow a precise evaluation of the peak cap-stress amplitude, which is known to be a good biomechanical predictor of plaque rupture. Several studies have been performed to reconstructa Young's modulus map from strain elastograms. It seems that the main issue for improving such methods does not rely on the optimization algorithm itself, but rather on preconditioning requiring the best estimation of the plaque components' contours. The present theoretical study was therefore designed to develop: 1) a preconditioning model to extract the plaque morphology in order to initiate the optimization process, and 2) an approach combining a dynamic segmentation method with an optimization procedure to highlight the modulogram of the atherosclerotic plaque. This methodology, based on the continuum mechanics theory prescribing the strain field, was successfully applied to seven intravascular ultrasound coronary lesion morphologies. The reconstructed cap thickness, necrotic core area, calcium area, and the Young's moduli of the calcium, necrotic core, and fibrosis were obtained with mean relative errors of 12%, 4% and 1%, 43%, 32%, and 2%, respectively. [ABSTRACT FROM AUTHOR]

We present a tool for tracking coronary vessels in MRI scans of the human heart to aid in the screening of heart diseases. The vessels are identified through a single click inside each vessel present in a standard orthogonal view. The vessel identification results from a series of computational steps including eigenvalue analysis of the Hessian of the MRI image followed by a level set-based extraction of the vessel centerline. All identified vessels are highlighted using a virtual contrast agent and displayed simultaneously in a spherical curved reformation view. In cases of over segmentation, the vessel traces can be shortened by a click on each vessel end point. Intermediate analysis results of the vessel computation steps can be displayed as well. We successfully validated the tool on 40 MRI scans demonstrating accuracy and significant time savings over manual vessel tracing. [ABSTRACT FROM AUTHOR]

An abstract of the conference paper "The feasibility of 350 micron spatial resolution coronary MRA at 3T in humans," by Ahmed Gharib and colleagues is presented.

Abstract: Hyper IgE recurrent infection syndrome (HIES, or Job’s syndrome) is a primary immunodeficiency characterized by recurrent skin and lung infections, eczema, elevated serum immunoglobulin E (IgE) levels, and various connective tissue and skeletal system abnormalities including characteristic facies, scoliosis, joint hyperextensibility, retained primary dentition, craniosynostosis, osteopenia, and pathologic fractures. We have identified two patients with aneurysmal coronary artery disease. One was a forty-three-year-old man with HIES and coronary artery aneurysms and ectasia identified on cardiac catheterization following myocardial infarction. The other was a 48-year-old man with coronary artery ectasia–aneurysm identified after cardiac catheterization for evaluation of chest pain. Although connective tissue abnormalities are common in HIES, this is the first report of coronary artery aneurysms in HIES. Further studies are necessary to determine the incidence, pathogenesis, and optimal therapy of these arterial abnormalities in HIES. [Copyright &y& Elsevier]

Background and aims Autosomal dominant hyper-IgE (AD-HIES) is a primary immunodeficiency caused by mutations in STAT3. Elevated levels of IgE, an ineffective immune response, connective tissue abnormalities, and coronary arterial dilation and tortuosity characterize AD-HIES. To date, coronary artery evaluation in AD-HIES patients has been limited to lumenography measurements. Direct in vivo coronary vessel wall (VW) imaging may allow for better interrogation of coronary vessel abnormalities. The goal of this prospective study was to evaluate the coronary VW of AD-HIES patients using Magnetic Resonance Imaging (MRI) and histology. VW image findings were compared in healthy subjects and subjects with coronary atherosclerotic disease (CAD). Methods A total of 28 subjects (10 with AD-HIES, 8 healthy, 10 with CAD) were studied by coronary VW MRI imaging. Additionally, a post-mortem coronary artery from one VW imaged AD-HIES patient was examined. Results Coronary VW in AD-HIES was thicker than in healthy controls but not significantly different from VW thickness in CAD subjects. AD-HIES coronaries showed increased VW area compared to healthy controls and CAD subjects. On histology, the AD-HIES coronary artery had findings consistent with atherosclerotic plaque, but had minimal luminal narrowing, deficient adventitia thickening and absence of both internal and external elastic laminae. Conclusions This is the first study to demonstrate subclinical coronary atherosclerosis in AD-HIES patients on VW imaging by MRI. Histologic evaluation confirmed the presence of atherosclerosis with lack of supportive adventitial thickening and elastic components. These findings suggest mechanisms for coronary dilation in AD-HIES and thereby help direct clinical management. [ABSTRACT FROM AUTHOR]