- Cardiovascular Function and Risk Factors
- Cardiac Imaging and Diagnostics
- Advanced MRI Techniques and Applications
- Cardiovascular Disease and Adiposity
- Congenital Heart Disease Studies
- Machine Learning in Healthcare
- Cardiac Valve Diseases and Treatments
- Cardiac Structural Anomalies and Repair
- Coronary Artery Anomalies
- Cardiovascular Health and Risk Factors
- Pulmonary Hypertension Research and Treatments
- Cardiovascular Effects of Exercise
- Phonocardiography and Auscultation Techniques
- Medical Imaging and Analysis
- Atomic and Subatomic Physics Research
- Hemodynamic Monitoring and Therapy
- Artificial Intelligence in Healthcare
- Topic Modeling
- Medical Image Segmentation Techniques
- COVID-19 diagnosis using AI
- Bayesian Methods and Mixture Models
- Elasticity and Material Modeling
- Cardiovascular Health and Disease Prevention
- Cardiomyopathy and Myosin Studies
- Radiation Dose and Imaging
University of Kentucky
2014-2021
We investigated the relationship between clinically assessed left ventricular ejection fraction (LVEF) and survival in a large, heterogeneous clinical cohort.
Obesity affects nearly one in five children and is associated with increased risk of premature death. Obesity-related heart disease contributes to We aimed use cardiovascular magnetic resonance (CMR) comprehensively characterize the changes cardiac geometry function obese children. Forty-one obese/overweight (age 12 ± 3 years, 56 % female) 29 healthy weight 14 41 underwent CMR, including both standard cine imaging displacement encoded imaging, for a complete assessment left ventricular (LV)...
Previous studies using regression analyses have failed to identify which patients with repaired tetralogy of Fallot (rTOF) are at risk for deterioration in ventricular size and function despite common clinical cardiac parameters as well mechanics (strain dyssynchrony). This study used a machine learning pipeline comprehensively investigate the predictive value baseline variables derived from magnetic resonance (CMR) imaging provide models identifying deterioration.
Patients with repaired tetralogy of Fallot (TOF) have progressive, adverse biventricular remodeling, leading to abnormal contractile mechanics. Defining the mechanisms underlying this dysfunction, such as diffuse myocardial fibrosis, may provide insights into poor long-term outcomes. We hypothesized that left ventricular (LV) fibrosis is related impaired LV TOF were evaluated cardiac magnetic resonance in which modified Look-Locker (MOLLI) T1-mapping and spiral cine Displacement encoding...
Children with obesity have hypertrophic cardiac remodeling. Hypertension is common in pediatric obesity, and may independently contribute to hypertrophy. We hypothesized that both the degree of ambulatory blood pressure (ABP) would associate measures remodeling children. Children, aged 8–17 years, prospectively underwent cardiovascular magnetic resonance (CMR) ABP monitoring. Left ventricular (LV) mass indexed height2.7 (LVMI), myocardial thickness end-diastolic volume were quantified from a...
Patients with repaired tetralogy of Fallot (rTOF) suffer from progressive ventricular dysfunction decades after their surgical repair. We hypothesized that measures strain and dyssynchrony would predict deterioration function in patients rTOF. A database search identified all at a single institution rTOF who underwent cardiovascular magnetic resonance (CMR) least twice, >6 months apart, without intervening or catheter procedures. Seven primary predictors were derived the first CMR using...
Cardiovascular magnetic resonance (CMR) feature tracking is increasingly used to quantify cardiac mechanics from cine CMR imaging, although validation against reference standard techniques has been limited. Furthermore, studies have suggested that commonly-derived metrics, such as peak global strain (reported in 63% of studies), can be quantified using contours just two frames – end-diastole (ED) and end-systole (ES) without requiring software. We hypothesized derived would not agree with...
Displacement Encoding with Stimulated Echoes (DENSE) encodes displacement into the phase of magnetic resonance signal. Due to stimulated echo, signal is inherently low and fades through cardiac cycle. To compensate, a spiral acquisition has been used at 1.5T. This sequence not validated 3T, where increased would be valuable, but field inhomogeneities may result in measurement errors. We hypothesized that cine DENSE valid 3T tested this hypothesis by measuring errors both 1.5T vivo....
Mechanics of the left ventricle (LV) are important indicators cardiac function. The role right ventricular (RV) mechanics is largely unknown due to technical limitations imaging its thin wall and complex geometry motion. By combining 3D Displacement Encoding with Stimulated Echoes (DENSE) a post-processing pipeline that includes local coordinate system, it possible quantify RV strain, torsion, synchrony. In this study, we sought characterize in 50 healthy individuals compare these values...
Pediatric obesity is a growing public health problem, which associated with increased risk of cardiovascular disease and premature death. Left ventricular (LV) remodeling (increased myocardial mass thickness) contractile dysfunction (impaired longitudinal strain) have been documented in obese children, but little attention has paid to the right ventricle (RV). We hypothesized that obese/overweight children would evidence RV dysfunction.
Cardiovascular magnetic resonance using displacement encoding with stimulated echoes (DENSE) is capable of assessing advanced measures cardiac mechanics such as strain and torsion. A potential hurdle to widespread clinical adoption DENSE the time required manually segment myocardium during post-processing images. To overcome this hurdle, we proposed a radical approach in which only three contours per image slice are for (instead typical 30–40 slice). We hypothesized that peak left...
Advanced cardiovascular magnetic resonance (CMR) acquisitions often require long scan durations that necessitate respiratory navigator gating. The tradeoff of gating is reduced efficiency, particularly when the patient's breathing patterns are inconsistent, as commonly seen in children. We hypothesized engaging pediatric participants with a navigator-controlled videogame to help control would improve efficiency and maintain image quality.
Displacement Encoding with Stimulated Echoes (DENSE) encodes displacement into the phase of magnetic resonance signal. The encoding frequency (ke) maps measured to tissue while strength gradients affects image quality. 2D cine DENSE studies have used a ke 0.10 cycles/mm, which is high enough remove an artifact-generating echo from k-space, provide sensitivity displacements, and dephase blood pool. However, through-plane dephasing can unwanted pool without relying on ke. Additionally, comes...
Rat models have assumed an increasingly important role in cardiac research. However, a detailed profile of regional mechanics, such as strains and torsion, is lacking for rats. We hypothesized that healthy rat left ventricles (LVs) exhibit differences which are part normal function. In this study, images the LV were obtained with 3D cine displacement encoding stimulated echoes (DENSE) cardiovascular magnetic resonance 10 To evaluate was divided into basal, mid-ventricular, apical regions....
Represents peak strain and twist measured using a particular encoding frequency.**Statistical significance between measures of mechanics paired-sample t-test at level α = 0.05.
Electronic health records (EHR) contain a large variety of information on the clinical history patients such as vital signs, demographics, diagnostic codes and imaging data. The enormous potential for discovery in this rich dataset is hampered by its complexity heterogeneity. We present first study to assess unsupervised homogenization pipelines designed EHR clustering. To identify optimal pipeline, we tested accuracy simulated data with varying amounts redundancy, heterogeneity,...
Left ventricular (LV) torsion is an important indicator of cardiac function that limited by high inter-test variability (50% the mean value). We hypothesized this partly due to inconsistent breath-hold positions during serial image acquisitions, which could be significantly improved using a respiratory navigator for cardiovascular magnetic resonance (CMR) based quantification LV torsion.
Background Obesity affects one in five children the US and these tend to maintain excess weight into adulthood. It has recently been shown that childhood obesity is associated with both cardiac remodeling (hypertrophy) contractile dysfunction. However, etiology of changes not well understood. We hypothesized dysfunction could be entirely explained by elevations blood pressure abdominal epicardial adiposity may also correlate changes.
Purpose To determine the optimal respiratory navigator gating configuration for quantification of left ventricular strain using spiral cine displacement encoding with stimulated echoes (DENSE) MRI. Materials and Methods Two‐dimensional DENSE was performed on a 3 Tesla MRI two single‐navigator configurations (retrospective, prospective) combined “dual‐navigator” in 10 healthy adults 20 children. The also underwent breathhold as reference standard comparisons. Peak strains, signal‐to‐noise...
Background Measures of left ventricular cardiac mechanics such as strains and torsion are becoming increasingly important for assessing heart function. Cardiac magnetic resonance (CMR) can be used to quantify using several methods tagged CMR or cine Displacement Encoding with Stimulated Echoes (DENSE). These images generally acquired during an end-expiratory breath-hold. Unfortunately, it is difficult subjects hold their breath at the exact same position when undergoing a series breath-holds...