Factors Influencing Image Quality in Fetal Cardiac Cine MRI Using Doppler US Gating:A Multicenter Study.

Background: Fetal cardiac cine MRI is an emerging technique for evaluating the fetal heart in conditions such as congenital heart disease, but limited evidence on factors affecting image quality restricts its clinical potential. This study investigated key determinants of image quality in a multicenter cohort.

Methods: This study analyzed fetal cardiac MRI scans from April 2021 to July 2023 at three centers (University Hospital Bonn, Children's Hospital Colorado, Phoenix Children's Hospital).

Quantitative evaluation of placental microvascular blood flow and microstructure in fetal growth restriction with IVIM MRI.

Background: Intravoxel incoherent motion (IVIM) MRI uses diffusion-weighted (DW) MRI acquisitions to evaluate the microvascular and cellular environments of tissue. Due to these properties, IVIM has been increasingly utilized to evaluate abnormal placentation.

Objective: Our primary objective was to compare IVIM parameters in the placenta of patients with fetal growth restriction and appropriate for gestational age controls across gestational ages.

Third trimester fetal 4D flow MRI with motion correction.

Purpose: To correct maternal breathing and fetal bulk motion during fetal 4D flow MRI.

Methods: A Doppler-ultrasound fetal cardiac-gated free-running 4D flow acquisition was corrected post hoc for maternal respiratory and fetal bulk motion in separate automated steps, with optional manual intervention to assess and limit fetal motion artifacts. Compressed-sensing reconstruction with a data outlier rejection algorithm was adapted from previous work.

Principal component analysis identified neo-aortic diameter variations post Norwood surgery associated with the single ventricle performance and flow quality.

The purpose of this study was to investigate neo-aortic curvature and diameter variation using the principal component analysis in patients who underwent a Norwood procedure for hypoplastic left heart syndrome. We further assessed whether neo-aortic curvature and diameter features are associated with clinical outcomes, single right ventricle function and flow hemodynamic patterns derived by 4D-Flow MRI. 55 patients with Fontan circulation who underwent a Norwood procedure in infancy underwent cardiac MRI as part of surveillance of their Fontan circulation.

Assessment of abnormal transvalvular flow and wall shear stress direction for pediatric/young adults with bicuspid aortic valve: A cross-sectional four-dimensional flow study.

Background: Aortic dilation is seen in pediatric/young adult patients with bicuspid aortic valve (BAV), and hemodynamic markers to predict aortic dilation are necessary for monitoring. Although promising hemodynamic metrics, such as abnormal wall shear stress (WSS) magnitude, have been proposed for adult BAV patients using four-dimensional (4D) flow cardiovascular magnetic resonance, those for pediatric BAV patients have less frequently been reported, partly due to scarcity of data to define normal WSS range. To circumvent this challenge, this study aims to investigate if a recently proposed 4D flow-based hemodynamic measurement, abnormal flow directionality, is associated with aortic dilation in pediatric/young adult BAV patients.

Fetal Cardiac MRI Using Doppler US Gating: Emerging Technology and Clinical Implications.

Fetal cardiac MRI using Doppler US gating is an emerging technique to support prenatal diagnosis of congenital heart disease and other cardiovascular abnormalities. Analogous to postnatal electrocardiographically gated cardiac MRI, this technique enables directly gated MRI of the fetal heart throughout the cardiac cycle, allowing for immediate data reconstruction and review of image quality. This review outlines the technical principles and challenges of cardiac MRI with Doppler US gating, such as loss of gating signal due to fetal movement.

Sleep duration and association with cardiometabolic health in adolescents and adults with type 1 diabetes: Results from the BCQR-T1D study.

Aim: Type 1 diabetes (T1D) increases the risk of morbidity and mortality from cardiovascular disease, and insufficient sleep is prevalent. Emerging evidence suggests a link between sleep and cardiometabolic health, but this has not been examined across the lifespan in individuals with T1D. We aimed to examine associations between sleep and cardiometabolic health in adolescents and adults with T1D in a secondary analysis of data from a 4-week double-blind, random-order, placebo-controlled crossover trial of bromocriptine quick release (BCQR) therapy with a 4-week washout in between conditions.

Multiyear Interval Changes in Aortic Wall Shear Stress in Patients with Bicuspid Aortic Valve Assessed by 4D Flow MRI.

Background: In patients with bicuspid aortic valve (BAV), 4D flow MRI can quantify regions exposed to abnormal aortic hemodynamics, including high wall shear stress (WSS), a known stimulus for arterial wall dysfunction. However, the long-term multiscan reproducibility of 4D flow MRI-derived hemodynamic parameters is unknown.

Purpose: To investigate the long-term stability of 4D flow MRI-derived peak velocity, WSS, and WSS-derived heatmaps in patients with BAV undergoing multiyear surveillance imaging.

Valvular and ascending aortic hemodynamics of the On-X aortic valved conduit by same-day echocardiography and 4D flow MRI.

This study aims to assess whether the On-X aortic valved conduit better restores normal valvular and ascending aortic hemodynamics than other commonly used bileaflet mechanical valved conduit prostheses from St. Jude Medical and Carbomedics by using same-day transthoracic echocardiography (TTE) and 4D flow magnetic resonance imaging (MRI) examinations. TTE and 4D flow MRI were performed back-to-back in 10 patients with On-X, six patients with St.

4D-Flow MRI intracardiac flow analysis considering different subtypes of pulmonary hypertension.

Intracardiac flow hemodynamic patterns have been considered to be an early sign of diastolic dysfunction. In this study we investigated right ventricular (RV) diastolic dysfunction between patients with pulmonary arterial hypertension (PAH) and pulmonary hypertension with chronic lung disease (PH-CLD) via 4D-Flow cardiac MRI (CMR). Patients underwent prospective, comprehensive CMR for function and size including 4D-Flow CMR protocol for intracardiac flow visualization and analysis.

The Inner Complexities of Multimodal Medical Data: Bitmap-Based 3D Printing for Surgical Planning Using Dynamic Physiology.

Motivated by the need to develop more informative and data-rich patient-specific presurgical planning models, we present a high-resolution method that enables the tangible replication of multimodal medical data. By leveraging voxel-level control of multimaterial three-dimensional (3D) printing, our method allows for the digital integration of disparate medical data types, such as functional magnetic resonance imaging, tractography, and four-dimensional flow, overlaid upon traditional magnetic resonance imaging and computed tomography data. While permitting the explicit translation of multimodal medical data into physical objects, this approach also bypasses the need to process data into mesh-based boundary representations, alleviating the potential loss and remodeling of information.

Reference Values for Fetal Cardiac Dimensions, Volumes, Ventricular Function and Left Ventricular Longitudinal Strain Using Doppler Ultrasound Gated Cardiac Magnetic Resonance Imaging in Healthy Third Trimester Fetuses.

Background: Recent advances in hardware and software permit the use of cardiac MRI of late gestation fetuses, however there is a paucity of MRI-based reference values.

Purpose: To provide initial data on fetal cardiac MRI-derived cardiac dimensions, volumes, ventricular function, and left ventricular longitudinal strain in healthy developing fetuses >30 weeks gestational age.

Study Type: Prospective.

Obesity dominates early effects on cardiac structure and arterial stiffness in people with type 2 diabetes.

Objective: Type 2 diabetes (T2D) and obesity are global epidemics leading to excess cardiovascular disease (CVD). This study investigates standard and novel cardiac MRI parameters to detect subclinical cardiac and central vascular dysfunction in inactive people with and without T2D.

Methods: Physically inactive age and BMI-similar premenopausal women and men with ( n  = 22) and without [ n  = 34, controls with overweight/obesity (CWO)] uncomplicated T2D were compared to an age-similar and sex-similar reference control cohort ( n  = 20).

Myocardial strain-curve deformation patterns after Fontan operation.

Myocardial deformation analysis by cardiac MRI (CMR) yielding global circumferential and longitudinal strain (GCS and GLS) is an increasingly utilized method to accurately quantify systolic function and predict clinical events in patients with Fontan circulation. The purpose of this study was to use principal component analysis (PCA) to investigate myocardial temporal deformation patterns derived from strain-time curves to learn about latent strain features beyond peak values. We conducted the study with specific attention to dominant single left or right ventricle (SLV and SRV) morphologies.

4D Flow cardiovascular magnetic resonance consensus statement: 2023 update.

Hemodynamic assessment is an integral part of the diagnosis and management of cardiovascular disease. Four-dimensional cardiovascular magnetic resonance flow imaging (4D Flow CMR) allows comprehensive and accurate assessment of flow in a single acquisition. This consensus paper is an update from the 2015 '4D Flow CMR Consensus Statement'.

Aortic shape variation after frozen elephant trunk procedure predicts aortic events: Principal component analysis study.

Objective: The frozen elephant trunk procedure is a well-established technique for the repair of type A ascending aortic dissection and complex aortic arch pathology. The ultimate shape created by the repair may have consequences in long-term complications. The purpose of this study was to apply a machine learning technique to comprehensively describe 3-dimensional aortic shape variations after the frozen elephant trunk procedure and associate these variations with aortic events.

A classification approach to improve out of sample predictability of structure-based constitutive models for ascending thoracic aortic tissue.

In this research, a pipeline was developed to assess the out-of-sample predictive capability of structure-based constitutive models of ascending aortic aneurysmal tissue. The hypothesis being tested is that a biomarker can help establish similarities among tissues sharing the same level of a quantifiable property, thus enabling the development of biomarker-specific constitutive models. Biomarker-specific averaged material models were constructed from biaxial mechanical tests of specimens that shared similar biomarker properties such as level of blood-wall shear stress or microfiber (elastin or collagen) degradation in the extracellular matrix.

Core-Shell Architecture in Poly(3-hexylthiophene) Nanoparticles: Tuning of the Photophysical Properties for Enhanced Neuronal Photostimulation.

This study shows that entirely thiophene-based core@shell nanoparticles, in which the shell is made of the oxidized form of the core polymer (P3HT@PTDO NPs), result in a type II interface at the particle surface. This enables the development of advanced photon nanotransducers with unique chemical-physical and biofunctional properties due to the core@shell nanoarchitecture. We demonstrate that P3HT@PTDO NPs present a different spatial localization of the excitation energy with respect to the nonoxidized NPs, showing a prevalence of surface states as a result of a different alignment of the HOMO/LUMO energy levels between the core and shell.

Magnetic resonance imaging-based hemodynamic wall shear stress alters aortic wall tissue biomechanics in bicuspid aortic valve patients.

Objective: In this study we aimed to conclusively determine whether altered aortic biomechanics are associated with wall shear stress (WSS) independent of region of tissue collection. Elevated WSS in the ascending aorta of patients with bicuspid aortic valve has been shown to contribute to local maladaptive aortic remodeling and might alter biomechanics.

Methods: Preoperative 4-dimensional flow magnetic resonance imaging was performed on 22 patients who underwent prophylactic aortic root and/or ascending aorta replacement.