James Carr

Northwestern University, Evanston, Illinois, United States

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Publications (133)668.49 Total impact

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    ABSTRACT: Atrial fibrillation (AF) is associated with embolic stroke due to thrombus formation in the left atrium (LA). Based on the relationship of atrial stasis to thromboembolism and the marked disparity in pulmonary versus systemic thromboembolism in AF, we tested the hypothesis that flow velocity distributions in the left (LA) versus right atrium (RA) in patients with would demonstrate increased stasis. Whole heart 4D flow MRI was performed in 62 AF patients (n = 33 in sinus rhythm during imaging, n = 29 with persistent AF) and 8 controls for the assessment of in vivo atrial 3D blood flow. 3D segmentation of the LA and RA geometry and normalized velocity histograms assessed atrial velocity distribution and stasis (% of atrial velocities <0.2 m/s). Atrial hemodynamics were similar for RA and LA and significantly correlated (mean velocity: r = 0.64; stasis: r = 0.55, p < 0.001). RA and LA mean and median velocities were lower in AF patients by 15-33 % and stasis was elevated by 11-19 % compared to controls. There was high inter-individual variability in LA/RA mean velocity ratio (range 0.5-1.8) and LA/RA stasis ratio (range 0.7-1.7). Patients with a history of AF and in sinus rhythm showed most pronounced differences in atrial flow (reduced mean velocities, higher stasis in the LA). While there is no systematic difference in LA versus RA flow velocity profiles, high variability was noted. Further delineation of patient specific factors and/or regional atrial effects on the LA and RA flow velocity profiles, as well as other factors such as differences in procoagulant factors, may explain the more prevalent systemic versus pulmonary thromboembolism in patients with AF.
    No preview · Article · Jan 2016 · The international journal of cardiovascular imaging
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    Full-text · Article · Jan 2016 · Journal of the American Heart Association

  • No preview · Article · Nov 2015
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    ABSTRACT: Objectives: Left atrial (LA) 4-dimensional flow magnetic resonance imaging (MRI) was used to derive anatomic maps of LA stasis, peak velocity, and time-to-peak (TTP) velocity in patients with atrial fibrillation (AF) and to identify relationships between LA flow with LA volume and patient characteristics. Materials and methods: Four-dimensional flow MRI for the in vivo assessment of time-resolved 3-dimensional LA blood flow velocities was performed in 111 subjects: 42 patients with a history of AF and in sinus rhythm (AF-sinus), 39 patients with persistent AF (AF-afib), 10 young healthy volunteers (HVs), and 20 age-appropriate controls (CTRL). Data analysis included the 3-dimensional segmentation of the LA and the calculation of LA stasis, peak velocity, and TTP maps. Regional LA flow dynamics were quantified by calculating mean stasis, peak velocity, and TTP in the LA center region and the region adjacent to the LA wall. Results: A sensitivity analysis identified thresholds for global LA stasis (<0.1 m/s) and peak velocity (top 5% LA velocities), which detected significant differences between AF patients and controls for global LA stasis (HV, 25% ± 5%; CTRL, 29% ± 10%; AF-sinus, 41% ± 13%; AF-afib, 52% ± 17%) and peak velocity (HV, 0.43 ± 0.02 m/s; CTRL, 0.37 ± 0.04 m/s; AF-sinus, 0.33 ± 0.05 m/s; AF-afib, 0.30 ± 0.05 m/s). Regional analysis revealed significantly increased stasis at both LA center and wall for AF patients compared with age-appropriate controls (29%-84% difference, P < 0.006) and for AF-afib versus AF-sinus patients (22%-30% difference, P < 0.004). In addition, stasis close to the LA wall was significantly elevated (P < 0.001) compared with the LA center for all subject groups. Multiple regressions revealed significant (RAdj = 0.45-0.50, P < 0.001) relationships between impaired global LA flow (reduced velocity and increased stasis) with age (|β| = 0.27-0.50, P < 0.002) and LA volume (|β| = 0.26-0.50, P < 0.003). Conclusions: Atrial 4-dimensional flow MRI detected changes in global and regional LA flow dynamics associated with AF, age, and LA volume. Longitudinal studies are needed to test the diagnostic value of LA flow metrics as potential risk factors for thromboembolic events.
    No preview · Article · Oct 2015 · Investigative radiology
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    ABSTRACT: Objective: The aim of this study was to systematically investigate a newly developed semiautomated workflow for the analysis of aortic 4-dimensional flow MRI and its ability to detect hemodynamic differences in patients with congenitally altered aortic valve (bicuspid or quadricuspid valves) compared with tricuspid aortic valves. Methods: Four-dimensional flow MRI data were acquired in 20 patients with aortic dilatation (9 tricuspid aortic valves, 11 congenitally altered aortic valves). A semiautomated workflow was evaluated regarding interobserver variability, accuracy of net flow, regurgitant fraction and peak systolic velocity, and the ability to detect differences between cohorts. Results were compared with manual segmentation of vessel contours. Results: Despite the significantly reduced analysis time, a good interobserver agreement was found for net flow and peak systolic velocity, and a moderate agreement was found for regurgitation. Significant differences in peak velocities in the descending aorta (P = 0.014) could be detected. Conclusions: Four-dimensional flow MRI-based semiautomated analysis of aortic hemodynamics can be performed with good reproducibility and accuracy.
    No preview · Article · Oct 2015 · Journal of computer assisted tomography
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    ABSTRACT: Purpose: Helical flow is often observed in patients with aortic dilation, aortic valve stenosis, or bicuspid aortic valve (BAV). In particular, local normalized helicity (LNH) can be used to characterize helical flow using both 2D measurements and multi-planar reformatting of 4D flow MRI 1-3. To improve on the limited coverage of these approaches, this study aims to use the full volume of the 4D flow MRI velocity fields to demonstrate that: 1) LNH volumetric quantification may differentiate helical flow alterations in the aorta between healthy controls and BAV subjects; 2) LNH volume may correlate with BAV aortic dilation and peak velocity. Methods: 115 subjects (65 healthy controls and 50 subjects with BAV and aortic dilatation were identified via IRB-approved retrospective chart review. Imaging was performed on 1.5T (n=74) and 3T (n=41) MRI (Siemens, Erlangen, Germany). The MRI protocol employed ECG-gated 4D flow during free breathing with adaptive navigator respiratory gating 4. Data were acquired in the sagittal oblique orientation, covering the entire aorta. Imaging parameters were: Venc=1.5–4 cm/s, TE/TR=2.3–2.84/4.6–5.4 ms, FOV=212–540 mm×132–326 mm, spatial resolution =1.66–2.81×1.66–2.81×2.2– 3.7 mm³, temporal resolution =36.8–43.2 ms, FA =15°. A phase contrast MR angiogram 4 (MRA) was calculated from 4D flow MRI data (Fig. 1A) and used to performed 3D segmentation of the entire aorta. LNH 1-3 in was calculated by í µí°¿í µí°¿í µí°¿í µí°¿í µí°¿í µí°¿ = í µí±‰í µí±‰.í µí¼”í µí¼” |í µí±‰í µí±‰||í µí¼”í µí¼”| , where V is the velocity field from 4D flow MRI and ω is the vorticity derived from V as given by ω=curl (V). A sensitivity analysis was perform to set the optimal absolute LNH threshold identifying elevated helicity within the flow domain. For LNH quantification, the aorta 3D segmentation was additionally subdivided in 3 segments: ascending aorta, aortic arch and descending aorta. The mean velocity in the entire aorta was used to identify peak systole, systole deceleration and mid-diastole phases. Results and Discussion: Absolute LNH volume sensitivity analysis lead to an optimal analysis threshold of 0.6. Absolute LNH volume was significantly higher (P<0.001) in BAV patients in comparison with controls for all evaluated segments and phases (Fig. 2). Absolute LNH volume in the ascending aorta correlated with MAA diameter (r=0.83, P<0.001, at peak systole; r=0.84, P<0.001, at systole deceleration; r=0.88, P<0.001, at mid-diastole). Previous studies have associated BAV with eccentric flow and elevated flow helicity in the MAA section, and it has been suggested that these flow alterations may contribute to the dilation of the aorta. This study showed that: 1) helical flow alterations can be identified by LNH and can be quantified by volume; 2) elevated LNH can differentiate helical flow alterations in healthy and BAV subjects; 3) elevated LNH was associated with BAV aortic dilation. Conclusion: In conclusion, this study demonstrates the potential usefulness of helical flow quantification to differentiate between controls and subjects with BAV and aortic dilation.
    Full-text · Conference Paper · Sep 2015
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    ABSTRACT: BACKGROUND Suspected genetic causes for extracellular matrix (ECM) dysregulation in the ascending aorta in patients with bicuspid aortic valves (BAV) have influenced strategies and thresholds for surgical resection of BAV aortopathy. Using 4-dimensional (4D) flow cardiac magnetic resonance imaging (CMR), we have documented increased regional wall shear stress (WSS) in the ascending aorta of BAV patients. OBJECTIVES This study assessed the relationship between WSS and regional aortic tissue remodeling in BAV patients to determine the influence of regional WSS on the expression of ECM dysregulation. METHODS BAV patients (n 1⁄4 20) undergoing ascending aortic resection underwent pre-operative 4D flow CMR to regionally map WSS. Paired aortic wall samples (i.e., within-patient samples obtained from regions of elevated and normal WSS) were collected and compared for medial elastin degeneration by histology and ECM regulation by protein expression. RESULTS Regions of increased WSS showed greater medial elastin degradation compared to adjacent areas with normal WSS: decreased total elastin (p 1⁄4 0.01) with thinner fibers (p 1⁄4 0.00007) that were farther apart (p 1⁄4 0.001). Multiplex protein analyses of ECM regulatory molecules revealed an increase in transforming growth factor b-1 (p 1⁄4 0.04), matrix metalloproteinase (MMP)-1 (p 1⁄4 0.03), MMP-2 (p 1⁄4 0.06), MMP-3 (p 1⁄4 0.02), and tissue inhibitor of metalloproteinase-1 (p 1⁄4 0.04) in elevated WSS regions, indicating ECM dysregulation in regions of high WSS. CONCLUSIONS Regions of increased WSS correspond with ECM dysregulation and elastic fiber degeneration in the ascending aorta of BAV patients, implicating valve-related hemodynamics as a contributing factor in the development of aortopathy. Further study to validate the use of 4D flow CMR as a noninvasive biomarker of disease progression and its ability to individualize resection strategies is warranted. (J Am Coll Cardiol 2015;66:892–900) © 2015 by the American College of Cardiology Foundation.
    Full-text · Article · Aug 2015 · Journal of the American College of Cardiology
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    ABSTRACT: Suspected genetic causes for extracellular matrix (ECM) dysregulation in the ascending aorta in patients with bicuspid aortic valves (BAV) have influenced strategies and thresholds for surgical resection of BAV aortopathy. Using 4-dimensional (4D) flow cardiac magnetic resonance imaging (CMR), we have documented increased regional wall shear stress (WSS) in the ascending aorta of BAV patients. This study assessed the relationship between WSS and regional aortic tissue remodeling in BAV patients to determine the influence of regional WSS on the expression of ECM dysregulation. BAV patients (n = 20) undergoing ascending aortic resection underwent pre-operative 4D flow CMR to regionally map WSS. Paired aortic wall samples (i.e., within-patient samples obtained from regions of elevated and normal WSS) were collected and compared for medial elastin degeneration by histology and ECM regulation by protein expression. Regions of increased WSS showed greater medial elastin degradation compared to adjacent areas with normal WSS: decreased total elastin (p = 0.01) with thinner fibers (p = 0.00007) that were farther apart (p = 0.001). Multiplex protein analyses of ECM regulatory molecules revealed an increase in transforming growth factor β-1 (p = 0.04), matrix metalloproteinase (MMP)-1 (p = 0.03), MMP-2 (p = 0.06), MMP-3 (p = 0.02), and tissue inhibitor of metalloproteinase-1 (p = 0.04) in elevated WSS regions, indicating ECM dysregulation in regions of high WSS. Regions of increased WSS correspond with ECM dysregulation and elastic fiber degeneration in the ascending aorta of BAV patients, implicating valve-related hemodynamics as a contributing factor in the development of aortopathy. Further study to validate the use of 4D flow CMR as a noninvasive biomarker of disease progression and its ability to individualize resection strategies is warranted. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
    No preview · Article · Aug 2015 · Journal of the American College of Cardiology
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    ABSTRACT: Hypertrophic cardiomyopathy (HCM) is associated with altered hemodynamics in the left ventricular outflow tract (LVOT) and myocardial tissue abnormalities such as fibrosis. The aim of this study was to quantify changes in LVOT 3D hemodynamics and myocardial extracellular volume fraction (ECV, measure of fibrosis) and to investigate relationships between elevated flow metrics and left ventricular (LV) tissue abnormalities. Cardiac magnetic resonance imaging (MRI) including 4D flow (field strength = 1.5T, resolution = 2.1-4.0 × 2.1-4.0 × 2.5-3.2 mm(3) ; venc = 150-250 cm/s; TE/TR/FA = 2.2-2.5msec/4.6-4.9msec/15°) for the in vivo assessment of 3D blood flow velocities with full coverage of the LVOT was applied in 35 patients with HCM (54 ± 15 years) and 10 age-matched healthy controls (45 ± 14 years). In addition, pre- and postcontrast myocardial T1 -mapping (resolution = 2.3 × 1.8 mm, slice thickness = 8 mm, TE/TR-FA = 1.0-1.1msec/2.0-2.2msec/35°) of the LV (basal, mid-ventricular, apical short axis) was performed in a subgroup of 23 HCM patients. Analysis included the segmentation of the LVOT and quantification of peak systolic LVOT pressure gradients and rate of viscous energy loss EL ' as well as left ventricular ECV. HCM patients demonstrated significantly elevated peak systolic LVOT pressure gradients (21 ± 16 mmHg vs. 9 ± 2 mmHg) and energy loss EL ' (3.8 ± 2.5 mW vs. 1.5 ± 0.7 mW, P < 0.005) compared to controls. There was a significant relationship between increased LV fibrosis (ECV) with both elevated pressure gradients (R(2) = 0.44, P < 0.001) and energy loss EL ' (R(2) = 0.46, P < 0.001). The integration of 4D-flow and T1 -mapping-MRI allowed for the evaluation of tissue and flow abnormalities in HCM patients. Our findings suggest a mechanistic link between abnormal LVOT flow, increased LV loading, and adverse myocardial remodeling in HCM. J. Magn. Reson. Imaging 2015. © 2015 Wiley Periodicals, Inc.
    Full-text · Article · Jul 2015 · Journal of Magnetic Resonance Imaging
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    ABSTRACT: Rosai-Dorfman disease (RDD) is a rare entity that usually involves the lymph nodes but extranodal involvements have been seen in numerous cases, although RDD with cardiovascular involvement is extremely rare. We describe a case of a young male who presented with intermittent palpitations and was found to have a left atrium mass. Our case not only emphasizes the rarity of the above lesion but also highlights the importance of modern-day imaging like computed tomography, Cardiac Magnetic Resonance Imaging (CMRI), and PET scan in characterizing such nonspecific lesions and directing appropriate line of treatment. RDD should be considered as one of the differentials even for isolated cardiac lesions.
    Full-text · Article · Jul 2015
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    ABSTRACT: Raghib Syndrome is a rare developmental complex, which consists of persistence of the left superior vena cava (PLSVC) along with coronary sinus ostial atresia and atrial septal defect. This Raghib complex anomaly has also been associated with other congenital malformations including ventricular septal defects, enlargement of the tricuspid annulus, and pulmonary stenosis. Our case demonstrates an isolated PLSVC draining into the left atrium along with coronary sinus atresia in a young patient presenting with cryptogenic stroke without the atrial septal defect. Majority of the cases reported in the literature were found to have the lesion during the postmortem evaluation or were characterized at angiography and/or echocardiography. We stress the importance of modern day imaging like the computed tomography (CT) angiography and cardiac MRI in diagnosis and surgical management of such rare lesions leading to cryptogenic strokes.
    Full-text · Article · Jun 2015
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    ABSTRACT: Smoking-related microvascular loss causes end-organ damage in the kidneys, heart and brain. Basic research suggests a similar process in the lungs but no large studies have assessed pulmonary microvascular blood flow (PMBF) in early chronic lung disease. We hypothesized that PMBF is reduced in mild as well as more severe COPD and emphysema. PMBF was measured using gadolinium-enhanced magnetic resonance imaging (MRI) among smokers with COPD and controls age 50-79 years without clinical cardiovascular disease. COPD severity was defined by standard criteria. Emphysema on computed tomography (CT) was defined by percent of lung regions <-950 Hounsfield units and radiologists using a standard protocol. We adjusted for potential confounders including smoking, oxygenation and left ventricular cardiac output. Among 144 participants, PMBF was reduced by 30% in mild COPD, 29% in moderate COPD and 52% in severe COPD (all P<0.01 vs. controls). PMBF was reduced with greater percent emphysema-950HU and radiologist-defined emphysema, particularly panlobular and centrilobular emphysema (all P≤0.01). Registration of MRI and CT images revealed that PMBF was reduced in mild COPD in both non-emphysematous and emphysematous lung regions. Associations for PMBF were independent of measures of small airways disease on CT and gas trapping largely since emphysema and small airways disease occurred in different smokers. PMBF was reduced in mild COPD, including in regions of lung without frank emphysema, and may represent a distinct pathological process from small airways disease. PMBF may provide an imaging biomarker for therapeutic strategies targeting the pulmonary microvasculature.
    No preview · Article · Jun 2015 · American Journal of Respiratory and Critical Care Medicine
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    ABSTRACT: Thoracic and abdominal 4D flow MRI is typically acquired in combination with navigator respiration control which can result in highly variable scan efficiency (Seff) and thus total scan time due to inter-individual variability in breathing patterns. The aim of this study was to test the feasibility of an improved respiratory control strategy based on diaphragm navigator gating with fixed Seff, respiratory driven phase encoding, and a navigator training phase. 4D flow MRI of the thoracic aorta was performed in 10 healthy subjects at 1.5T and 3T systems for the in-vivo assessment of aortic time-resolved 3D blood flow velocities. For each subject, four 4D flow scans (1: conventional navigator gating, 2-4: new implementation with fixed Seff =60%, 80% and 100%) were acquired. Data analysis included semi-quantitative evaluation of image quality of the 4D flow magnitude images (image quality grading on a four point scale), 3D segmentation of the thoracic aorta, and voxel-by-voxel comparisons of systolic 3D flow velocity vector fields between scans. Conventional navigator gating resulted in variable Seff = 74±13% (range = 56% - 100%) due to inter-individual variability of respiration patterns. For scans 2-4, the the new navigator implementation was able to achieve predictable total scan times with stable Seff, only depending on heart rate. Semi- and fully quantitative analysis of image quality in 4D flow magnitude images was similar for the new navigator scheme compared to conventional navigator gating. For aortic systolic 3D velocities, good agreement was found between all new navigator settings (scan 2-4) with the conventional navigator gating (scan 1) with best performance for Seff = 80% (mean difference = -0.01; limits od agreement = 0.23, Pearson's ρ=0.89, p <0.001). No significant differences for image quality or 3D systolic velocities were found for 1.5T compared to 3T. The findings of this study demonstrate the feasibility of the new navigator scheme to acquire 4D flow data with more predictable scan time while maintaining image quality and 3D velocity information, which may prove beneficial for clinical applications. Copyright © 2015. Published by Elsevier Inc.
    Full-text · Article · May 2015 · Magnetic Resonance Imaging
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    Full-text · Conference Paper · May 2015
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    Full-text · Conference Paper · May 2015
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    ABSTRACT: To assess changes in portal and splanchnic arterial haemodynamics in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) using four-dimensional (4D) flow MRI, a non-invasive, non-contrast imaging technique. Eleven patients undergoing TIPS implantation were enrolled. K-t GRAPPA accelerated non-contrast 4D flow MRI of the liver vasculature was applied with acceleration factor R = 5 at 3Tesla. Flow analysis included three-dimensional (3D) blood flow visualization using time-resolved 3D particle traces and semi-quantitative flow pattern grading. Quantitative evaluation entailed peak velocities and net flows throughout the arterial and portal venous (PV) systems. MRI measurements were taken within 24 h before and 4 weeks after TIPS placement. Three-dimensional flow visualization with 4D flow MRI revealed good image quality with minor limitations in PV flow. Quantitative analysis revealed a significant increase in PV flow (562 ± 373 ml/min before vs. 1831 ± 965 ml/min after TIPS), in the hepatic artery (176 ± 132 ml/min vs. 354 ± 140 ml/min) and combined flow in splenic and superior mesenteric arteries (770 ml/min vs. 1064 ml/min). Shunt-flow assessment demonstrated stenoses in two patients confirmed and treated at TIPS revision. Four-dimensional flow MRI might have the potential to give new information about the effect of TIPS placement on hepatic perfusion. It may explain some unexpected findings in clinical observation studies. • 4D flow MRI, a non-invasive, non-contrast imaging technique, is feasible after TIPS. • Provides visualization and quantification of hepatic arterial, portal venous, collateral and TIPS haemodynamics. • Better understanding of liver blood flow changes after TIPS and patient management.
    No preview · Article · Apr 2015 · European Radiology

  • No preview · Article · Mar 2015 · Circulation
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    ABSTRACT: The role of atherosclerosis in the progression of global left ventricular dysfunction and cardiovascular events has been well recognized. Left ventricular (LV) dyssynchrony is a measure of regional myocardial dysfunction. Our objective was to investigate the relationship of subclinical atherosclerosis with mechanical LV dyssynchrony in a population-based asymptomatic multi-ethnic cohort. Participants of the Multi-Ethnic Study of Atherosclerosis (MESA) at exam 5 were evaluated using 1.5T cardiac magnetic resonance (CMR) imaging, carotid ultrasound (n = 2062) for common carotid artery (CCA) and internal carotid artery (ICA) intima-media thickness (IMT), and cardiac computed tomography (n = 2039) for coronary artery calcium (CAC) assessment (Agatston method). Dyssynchrony indices were defined as the standard deviation of time to peak systolic circumferential strain (SD-TPS) and the difference between maximum and minimum (max-min) time to peak strain using harmonic phase imaging in 12 segments (3-slices × 4 segments). Multivariable regression analyses were performed to assess associations after adjusting for participant demographics, cardiovascular risk factors, LV mass, and ejection fraction. In multivariable analyses, SD-TPS was significantly related to measures of atherosclerosis, including CCA-IMT (8.7 ms/mm change in IMT, p = 0.020), ICA-IMT (19.2 ms/mm change in IMT, p < 0.001), carotid plaque score (1.2 ms/unit change in score, p < 0.001), and log transformed CAC+1 (0.66 ms/unit log-CAC+1, p = 0.018). These findings were consistent with other parameter of LV dyssynchrony i.e. max-min. In the MESA cohort, measures of atherosclerosis are associated with parameters of subclinical LV dyssynchrony in the absence of clinical coronary event and left-bundle-branch block. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
    No preview · Article · Feb 2015 · Atherosclerosis
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    ABSTRACT: Nonischemic cardiomyopathy is a common cause of left ventricular (LV) dysfunction and myocardial fibrosis. The purpose of this study was to noninvasively evaluate changes in segmental LV extracellular volume (ECV) fraction, LV velocities, myocardial scar, and wall motion in nonischemic cardiomyopathy patients. Cardiac MRI including pre- and postcontrast myocardial T1 mapping and velocity quantification (tissue phase mapping) of the LV (basal, midventricular, and apical short axis) was applied in 31 patients with nonischemic cardiomyopathy (50±18 years). Analysis based on the 16-segment American Heart Association model was used to evaluate the segmental distribution of ECV, peak systolic and diastolic myocardial velocities, scar determined by late gadolinium enhancement, and wall motion abnormalities. LV segments with scar or impaired wall motion were significantly associated with elevated ECV (rs =0.26; P<0.001) and reduced peak systolic radial velocities (r=-0.43; P<0.001). Regional myocardial velocities and ECV were similar for patients with reduced (n=12; ECV=0.28±0.06) and preserved left ventricular ejection fraction (n=19; ECV=0.30±0.09). Patients with preserved left ventricular ejection fraction showed significant relationships between increasing ECV and reduced systolic (r=-0.19; r=-0.30) and diastolic (r=0.34; r=0.26) radial and long-axis peak velocities (P<0.001). Even after excluding myocardial segments with late gadolinium enhancement, significant relationships between ECV and segmental LV velocities were maintained indicating the potential of elevated ECV to identify regional diffuse fibrosis not visible by late gadolinium enhancement, which was associated with impaired regional LV function. Regionally elevated ECV negatively affected myocardial velocities. The association of elevated regional ECV with reduced myocardial velocities independent of left ventricular ejection fraction suggests a structure-function relationship between altered ECV and segmental myocardial function in nonischemic cardiomyopathy. © 2014 American Heart Association, Inc.
    Preview · Article · Jan 2015 · Circulation Cardiovascular Imaging

  • No preview · Conference Paper · Nov 2014

Publication Stats

1k Citations
668.49 Total Impact Points

Institutions

  • 2001-2015
    • Northwestern University
      • • Feinberg School of Medicine
      • • Department of Radiology
      • • Department of Biomedical Engineering
      Evanston, Illinois, United States
  • 2014
    • University of Texas Southwestern Medical Center
      • Department of Neurology and Neurotherapeutics
      Dallas, Texas, United States
  • 2003-2013
    • Northwestern Memorial Hospital
      • Department of Radiology
      Chicago, Illinois, United States
  • 2008
    • University of Chicago
      Chicago, Illinois, United States