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Background Routine cine cardiovascular magnetic resonance (CMR) allows for the measurement of left atrial (LA) volumes. Normal reference values for LA volumes have been published based on a group of European individuals without known cardiovascular disease (CVD) but not on one of similar United States (US) based volunteers. Furthermore, the association between grades of LA dilatation by CMR and outcomes has not been established. We aimed to assess the relationship between grades of LA dilatation measured on CMR based on US volunteers without known CVD and all-cause mortality in a large, multicenter cohort of patients referred for a clinically indicated CMR scan. Method We identified 85 healthy US subjects to determine normal reference LA volumes using the biplane area-length method and indexed for body surface area (LAVi). Clinical CMR reports of patients with LA volume measures (n = 11,613) were obtained. Data analysis was performed on a cloud-based system for consecutive CMR exams performed at three geographically distinct US medical centers from August 2008 through August 2017. We identified 10,890 eligible cases. We categorized patients into 4 groups based on LAVi partitions derived from US normal reference values: Normal (21–52 ml/m2), Mild (52–62 ml/m2), Moderate (63–73 ml/m2) and Severe (> 73 ml/m2). Mortality data were ascertained for the patient group using electronic health records and social security death index. Cox proportional hazard risk models were used to derive hazard ratios for measuring association of LA enlargement and all-cause mortality. Results The distribution of LAVi from healthy subjects without known CVD was 36.3 ± 7.8 mL/m2. In clinical patients, enlarged LA was associated with older age, atrial fibrillation, hypertension, heart failure, inpatient status and biventricular dilatation. The median follow-up duration was 48.9 (IQR 32.1–71.2) months. On univariate analyses, mild [Hazard Ratio (HR) 1.35 (95% Confidence Interval [CI] 1.11 to 1.65], moderate [HR 1.51 (95% CI 1.22 to 1.88)] and severe LA enlargement [HR 2.14 (95% CI 1.81 to 2.53)] were significant predictors of death. After adjustment for significant covariates, moderate [HR 1.45 (95% CI 1.1 to 1.89)] and severe LA enlargement [HR 1.64 (95% CI 1.29 to 2.08)] remained independent predictors of death. Conclusion LAVi determined on routine cine-CMR is independently associated with all-cause mortality in patients undergoing a clinically indicated CMR.

Background Multiple gated acquisition scanning (MUGA) is a common imaging modality for baseline and serial assessment of left ventricular ejection fraction (LVEF) for cardiotoxicity risk assessment prior to, surveillance during, and surveillance after administration of potentially cardiotoxic cancer treatment. The objective of this study was to compare the accuracy of left ventricular ejection fractions (LVEF) obtained by contemporary clinical multiple gated acquisition scans (MUGA) with reference LVEFs from cardiovascular magnetic resonance (CMR) in consecutive patients with cancer. Methods In a cross-sectional study, we compared MUGA clinical and CMR reference LVEFs in 75 patients with cancer who had both studies within 30 days. Misclassification was assessed using the two most common thresholds of LVEF used in cardiotoxicity clinical studies and practice: 50 and 55%. Results Compared to CMR reference LVEFs, MUGA clinical LVEFs were only lower by a mean of 1.5% (48.5% vs. 50.0%, p = 0.17). However, the limits of agreement between MUGA clinical and CMR reference LVEFs were wide at −19.4 to 16.5%. At LVEF thresholds of 50 and 55%, there was misclassification of 35 and 20% of cancer patients, respectively. Conclusions MUGA clinical LVEFs are only modestly accurate when compared with CMR reference LVEFs. These data have significant implications on clinical research and patient care of a population with, or at risk for, cardiotoxicity.

Background Infarct size is increasingly used as an efficacy endpoint in randomized trials comparing acute myocardial infarct (AMI) therapies. Infarct size, depicted by delayedenhancement-CMR, is quantified using manual planimetry (MANUAL), visual scoring (VISUAL), or automated techniques using signal-intensity thresholding to define infarct borders (AUTO). Although AUTO is considered the most reproducible, prior studies did not account for the subjective determination of endocardial/epicardial borders, which all methods require. For MANUAL and VISUAL, prior studies have not explicitly defined how to treat intermediate signal-intensities due to partial volume. We wanted to assess sources of variability among 6 methods in quantification of AMI size, and illustrate the significance of these findings on sample size calculations for clinical trials.

In this report, we describe a case of primary pericardial mesothelioma, which is an extremely rare tumor arising from mesothelial cells lining the pericardium and is associated with a dismal prognosis.

Background Imaging in patients with renal insufficiency (RI) is limited by contrast induced nephropathy and nephrogenic systemic fibrosis. Ferumoxytol is an FDA approved superparamagnetic iron compound used for the treatment of anemia in patients with renal insufficiency. Previous studies of its use as an MRA contrast agent did not assess safety, were not conducted in patients with RI, and were limited by small sample size. We characterized the safety, image quality, and clinical impact of ferumoxytol-enhanced MRA (FeMRA) in patients with RI as compared to gadoliniumenhanced MRA (GeMRA) in patients without RI.

Background Mitral regurgitation (MR) is clinically important for patients with prosthetic mitral valves (PMV). While CMR can quantify MR based on flow, this requires dedicated imaging. Cine-CMR (SSFP) provides an alternative approach, whereby MR can be graded based on regurgitation-associated intervoxel dephasing. As cine-CMR is a standard component of nearly all exams, it could be used to screen for patients who warrant further quantitative imaging. Diagnostic performance of cine-CMR for prosthesis-associated MR has not been evaluated. Methods Databases at 6 sites were queried for all patients with PMV in whom CMR and echocardiography were performed within 10 days. Cine-CMR images were retrieved and interpreted using a uniform protocol: MR was visually graded based solely on jet size (mild 2/3) in relation to the left atrium. MR was graded in each long axis plane (2-,3-, 4-chamber), with overall severity based on mean grade. Additional parameters included jet directionality, signal intensity (3-grade scale), and pulmonary vein flow reversal. Echocardiography (TTE, TEE) was used as a comparator for MR based on clinically reported data. Cine-CMR was interpreted blinded to patient history and TTE/TEE. Results 56 patients with PMV (70% mechanical, 30% bio) underwent cine-CMR and echo (TTE 70%, TEE 48%) within 2.5±2.6 days. Cine-CMR (1.5T, typical TR=3msec, TE=1msec, BW=977Hz/pixel) was performed using commercial scanners (Siemens 59%/GE 36%/Philips 5%). MR was present on cine-CMR in 77% of patients (mild 43%, moderate 14%, severe 20%), and varied in direction (central 88%, eccentric 12%). Patients with severe MR had higher prevalence of dense regurgitant jets (73% vs. 3%, p

Background Adenosine stress CMR with visual interpretation is increasingly used in the evaluation of patients with CAD. The definition of a stress perfusion defect is inconsistent in the literature regarding i) the duration from contrast arrival, ii) persistence relative to a remote segment, iii) transmural extent, and iv) reversibility on rest perfusion. In this study we sought to test several semi-quantitative parameters assessed by rapid visual analysis, and determine their utility to identify stress-perfusion defects from obstructive CAD.

Background Intravenous iron-supplementation drugs are frequently used for treatment of iron-deficiency anemia in chronic kidney disease. Some iron-agents alter tissue T1-relaxation times (T1) for days after administration, and could obscure MRI diagnosis. Conversely, these agents may have the potential to delineate pathology. We sought to investigate the T1-shortening effect of ferumoxytol and iron-dextran, determine how T1 of blood, liver, and myocardium change over time in-vivo after iron administration, and explore the utility of these agents for imaging acute myocardial infarction (MI). Methods We determined in-vitro T1 of ferumoxytol and irondextran (20mg Fe ad 500ml 0.9%NaCl). Seven dogs with acute, reperfused MI were scanned five days later on a 3.0T MRI-scanner, at which time ferumoxytol (n=5) or iron-dextran (n=2) was administered in clinically used doses (approx. 130mg iron). Inversion-recovery, gradient-echo images with various inversion-times (1151600ms) were acquired prior to and serially after ironinjection at multiple time-points on day 1 (n=7), 2 (n=5), 3 (n=2), and 7 (n=7). T1 was determined by standard curve-fitting. Results In-vitro T1 of ferumoxytol and iron-dextran were 13% and 89% of 0.9%NaCl, respectively. T1 of blood, myocardium, and liver were 2027±421ms, 1384±143ms, and 806±74ms, respectively. Results for ferumoxytol were: T1 of blood dropped to 7% (p 0.05). Conclusions Ferumoxytol may affect cardiovascular MR beyond 2 days and liver MR beyond 1 week after administration of doses used clinically for iron-deficiency anemia. Unless recognized, this could affect MRI diagnosis. The differential kinetics suggest a potential use of ferumoxytol for delineation of acute MI.