Human iPSC-derived Committed Cardiac Progenitors Generate Cardiac Tissue Grafts in a Swine Ischemic Cardiomyopathy Model without Triggering Ventricular Arrhythmias.

Background: The adult human heart following a large myocardial infarction is unable to regenerate heart muscle and instead forms scar with the risk of progressive heart failure. Large animal studies have shown that intramyocardial injection of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) following a myocardial infarction result in cell grafts but also ventricular arrhythmias. We hypothesized that intramyocardial injection of committed cardiac progenitor cells (CCPs) derived from iPSCs, combined with cardiac fibroblast-derived extracellular matrix (cECM) to enhance cell retention will: i) form cardiomyocyte containing functional grafts, ii) be free of ventricular arrhythmias and iii) restore left ventricular contractility in a post-myocardial infarction (MI) cardiomyopathy swine model.

MR Angiography of Pulmonary Vasculature.

Pulmonary MR angiography (MRA) is a useful alternative to computed tomographic angiography (CTA) for the study of the pulmonary vasculature. For pulmonary hypertension and partial anomalous pulmonary venous return, a cardiac MR imaging and the pulmonary MRA are useful for flow quantification and planning treatment. For the diagnosis of pulmonary embolism (PE), MRA-PE has been shown to have non-inferior outcomes at 6 months when compared with CTA-PE.

MRA as the Preferred Test for Pulmonary Embolism During the Iodinated Contrast Media Shortage of 2022: A Single-Center Experience.

Closure of a GE Healthcare facility in Shanghai, China, in 2022 disrupted the iodinated contrast media supply. Technologic advances have addressed limitations associated with the use of pulmonary MRA for diagnosis of pulmonary embolism (PE). The purpose of this study was to describe a single institution's experience in the use of pulmonary MRA as an alternative to CTA for the diagnosis of PE in the general population during the iodinated contrast media shortage in 2022.

Pulmonary MRA During Pregnancy: Early Experience With Ferumoxytol.

Background: Ferumoxytol, an intravenous iron supplement, is commonly used to treat anemia in pregnancy. Ferumoxytol-enhanced magnetic resonance angiography (Fe-MRA) is a viable off-label alternative to gadolinium-enhanced MRA for assessment of pulmonary embolism (PE) in pregnancy.

Purpose: To describe our clinical experience with Fe-MRA in pregnant women with suspected PE.

Left upper lobe and lingula torsion after transplantation of single lung with complete major and minor fissures: A case report.

Background: Native lung torsion is rare and torsion in a lung transplant is even rarer.

Case Presentation: Here we report a case of left upper lobe (LUL) and lingula torsion in a patient with a unilateral left lung transplantation. The transplant was complicated by a graft with a short pulmonary artery cuff, which required significant vascular reconstruction and manipulation.

Patient Preferences for Diagnostic Imaging: CTA vs MRA When Diagnosing Pulmonary Embolism.

Objective: To identify preferences regarding choice of diagnostic imaging (computed tomographic angiography [CTA] vs magnetic resonance angiography [MRA]) for the evaluation of pulmonary embolism.

Methods: We conducted 4 focus group discussions with residents of 2 Wisconsin cities. Community members ≥18 years old were recruited via telephone using a commercially available telephone database.

Feasibility and optimization of ultra-short echo time MRI for improved imaging of IVC-filters at 3.0 T.

Purpose: To determine the feasibility of ultra-short echo time (UTE) MRA for assessment of inferior vena cava (IVC) filters and evaluate the impact of different imaging protocols at 3.0 T, using conventional Cartesian MRA (cMRA) as the reference standard.

Methods: Patients with IVC-filters were recruited for this prospective IRB-approved, HIPAA-compliant study.

Guidance for computed tomography (CT) imaging of the lungs for patients with cystic fibrosis (CF) in research studies.

Numerous issues must be addressed when developing standard operating procedures for clinical research studies involving chest computed tomography of lung disease in patients with cystic fibrosis (CF). Study success depends on the provision of adequate funding and the identification of personnel with the necessary expertise to conduct the study, along with clear guidelines that detail the CT operating procedure at each site, including breathing maneuvers, and image reconstruction. Close coordination of the quality assurance process between sites and the central review organization is required to maintain protocol adherence.

Comparison of gadolinium-enhanced and ferumoxytol-enhanced conventional and UTE-MRA for the depiction of the pulmonary vasculature.

Purpose: To evaluate the feasibility of ferumoxytol (FE)-enhanced UTE-MRA for depiction of the pulmonary vascular and nonvascular structures.

Methods: Twenty healthy volunteers underwent contrast-enhanced pulmonary MRA at 3 T during 2 visits, separated by at least 4 weeks. Visit 1: The MRA started with a conventional multiphase 3D T -weighted breath-held spoiled gradient-echo MRA before and after the injection of 0.

Deep convolutional neural networks with multiplane consensus labeling for lung function quantification using UTE proton MRI.

Background: Ultrashort echo time (UTE) proton MRI has gained popularity for assessing lung structure and function in pulmonary imaging; however, the development of rapid biomarker extraction and regional quantification has lagged behind due to labor-intensive lung segmentation.

Purpose: To evaluate a deep learning (DL) approach for automated lung segmentation to extract image-based biomarkers from functional lung imaging using 3D radial UTE oxygen-enhanced (OE) MRI.

Study Type: Retrospective study aimed to evaluate a technical development.

"Structure-Function Imaging of Lung Disease Using Ultrashort Echo Time MRI".

Rationale And Objectives: The purpose of this review is to acquaint the reader with recent advances in ultrashort echo time (UTE) magnetic resonance imaging (MRI) of the lung and its implications for pulmonary MRI when used in conjunction with functional MRI technique.

Materials And Methods: We provide an overview of recent technical advances of UTE and explore the advantages of combined structure-function pulmonary imaging in the context of restrictive and obstructive pulmonary diseases such as idiopathic pulmonary fibrosis (IPF) and cystic fibrosis (CF).

Results: UTE MRI clearly shows the lung parenchymal changes due to IPF and CF.

Three-dimensional Isotropic Functional Imaging of Cystic Fibrosis Using Oxygen-enhanced MRI: Comparison with Hyperpolarized He MRI.

Purpose To compare the performance of three-dimensional radial ultrashort echo time (UTE) oxygen-enhanced (OE) MRI with that of hyperpolarized helium 3 (He) MRI with respect to quantitative ventilation measurements in patients with cystic fibrosis (CF). Materials and Methods In this prospective study conducted from June 2013 to May 2015, 25 participants with CF aged 10-55 years (14 male; age range, 13-55 years; 11 female; age range, 10-37 years) successfully underwent pulmonary function tests, hyperpolarized He MRI, and OE MRI. OE MRI used two sequential 3.

Clinical outcomes after magnetic resonance angiography (MRA) versus computed tomographic angiography (CTA) for pulmonary embolism evaluation.

Purpose: To compare patient outcomes following magnetic resonance angiography (MRA) versus computed tomographic angiography (CTA) ordered for suspected pulmonary embolism (PE).

Methods: In this IRB-approved, single-center, retrospective, case-control study, we reviewed the medical records of all patients evaluated for PE with MRA during a 5-year period along with age- and sex-matched controls evaluated with CTA. Only the first instance of PE evaluation during the study period was included.

Downstream Imaging Utilization After MR Angiography Versus CT Angiography for the Initial Evaluation of Pulmonary Embolism.

Objective: To compare the proportion of emergency department (ED) patients who undergo subsequent chest CT or MR within 1 year of an initially negative scan for pulmonary embolism (PE).

Methods: This single-center, retrospective, observational study examined the use of chest CT or MR for ED patients with MR angiography (MRA) negative for PE during April 2008 to March 2013. We compared the 1-year scan utilization for these cases to an age- and sex-matched cohort of patients who underwent CT angiography (CTA).

Mucus plugs in patients with asthma linked to eosinophilia and airflow obstruction.

Background: The link between mucus plugs and airflow obstruction has not been established in chronic severe asthma, and the role of eosinophils and their products in mucus plug formation is unknown.

Methods: In clinical studies, we developed and applied a bronchopulmonary segment-based scoring system to quantify mucus plugs on multidetector computed tomography (MDCT) lung scans from 146 subjects with asthma and 22 controls, and analyzed relationships among mucus plug scores, forced expiratory volume in 1 second (FEV1), and airway eosinophils. Additionally, we used airway mucus gel models to explore whether oxidants generated by eosinophil peroxidase (EPO) oxidize cysteine thiol groups to promote mucus plug formation.

Regional Heterogeneity of Lobar Ventilation in Asthma Using Hyperpolarized Helium-3 MRI.

Rationale And Objectives: To determine lobar ventilation patterns in asthmatic lungs with hyperpolarized He magnetic resonance imaging (HP He MRI).

Materials And Methods: Eighty-two subjects (14 normal, 48 mild-to-moderate asthma, and 20 severe asthma) underwent HP He MRI, computed tomography (CT), and pulmonary function testing. After registering proton to He images, we segmented the lungs from proton MRI and further segmented the five lung lobes (right upper lobe [RUL], right middle lobe [RML], and right lower lobe [RLL]; left upper lobe and left lower lobe [LLL]) by referring to the lobar segmentation from CT.

Pulmonary ventilation imaging in asthma and cystic fibrosis using oxygen-enhanced 3D radial ultrashort echo time MRI.

Background: A previous study demonstrated the feasibility of using 3D radial ultrashort echo time (UTE) oxygen-enhanced MRI (UTE OE-MRI) for functional imaging of healthy human lungs. The repeatability of quantitative measures from UTE OE-MRI needs to be established prior to its application in clinical research.

Purpose: To evaluate repeatability of obstructive patterns in asthma and cystic fibrosis (CF) with UTE OE-MRI with isotropic spatial resolution and full chest coverage.

Motion robust high resolution 3D free-breathing pulmonary MRI using dynamic 3D image self-navigator.

Purpose: To achieve motion robust high resolution 3D free-breathing pulmonary MRI utilizing a novel dynamic 3D image navigator derived directly from imaging data.

Methods: Five-minute free-breathing scans were acquired with a 3D ultrashort echo time (UTE) sequence with 1.25 mm isotropic resolution.

Magnetic Resonance Imaging for the Evaluation of Pulmonary Embolism.

Pulmonary embolism (PE) is a leading cause of acute cardiovascular death throughout the world. Although computed tomography angiography (CTA) is the primary imaging study used to diagnose acute PE, pulmonary magnetic resonance angiography (MRA) is increasingly being used in patients with contraindications for CTA. This manuscript reviews the MRA techniques used for the diagnosis of PE and discuss how these techniques can be implemented in routine clinical practice.

Contrast-enhanced pulmonary MRA for the primary diagnosis of pulmonary embolism: current state of the art and future directions.

CT pulmonary angiography (CTPA) is currently considered the imaging standard of care for the diagnosis of pulmonary embolism (PE). Recent advances in contrast-enhanced pulmonary MR angiography (MRA) techniques have led to increased use of this modality for the detection of PE in the proper clinical setting. This review is intended to provide an introduction to the state-of-the-art techniques used in pulmonary MRA for the detection of PE and to discuss possible future directions for this modality.

Negative D-dimer testing excludes pulmonary embolism in non-high risk patients in the emergency department.

Purpose: The purpose of this study was to assess the ability of d-dimer testing to obviate the need for cross-sectional imaging for patients at "non-high risk" for pulmonary embolism (PE).

Methods: This is a retrospective study of emergency department patients at an academic medical center who underwent cross-sectional imaging (MRA or CTA) to evaluate for PE from 2008 to 2013. The primary outcome was the NPV of d-dimer testing when used in conjunction with clinical decision instruments (CDIs = Wells', Revised Geneva, and Simplified Revised Geneva Scores).

Anemia is not a risk factor for developing pulmonary embolism.

Objective: Our aim was to validate the previously published claim of a positive relationship between low blood hemoglobin level (anemia) and pulmonary embolism (PE).

Methods: This was a retrospective study of patients undergoing cross-sectional imaging to evaluate for PE at an academic medical center. Patients were identified using billing records for charges attributed to either magnetic resonance angiography or computed tomography angiography of the chest from 2008 to 2013.