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Troger F, Tiller C, Reindl M, Lechner I, Holzknecht M, Pamminger M, Poskaite P, Kremser C, Ulmer H, Gizewski ER, Bauer A, Reinstadler S, Metzler B, Klug G, Mayr A. Slice positioning in phase-contrast MRI impacts aortic stenosis assessment. Eur J Radiol 2023; 161:110722. [PMID: 36758278 DOI: 10.1016/j.ejrad.2023.110722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/27/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023]
Abstract
AIMS To determine the phase-contrast cardiovascular magnetic resonance imaging (PC-CMR) slice-position above aortic leaflet-attachment-plane (LAP) that provides flow-velocity, -volume and aortic valve area (AVA) measurements with best agreement to invasive and echocardiographic measurements in aortic stenosis (AS). METHODS AND RESULTS Fifty-five patients with moderate/severe AS underwent cardiac catheterization, transthoracic echocardiography (TTE) and CMR. Overall, 171 image-planes parallel to LAP were measured via PC-CMR between 22 mm below and 24 mm above LAP. AVA via PC-CMR was calculated as flow-volume divided by peak-velocity during systole. Stroke volume (SV) and AVA were compared to volumetric SV and invasive AVA via the Gorlin-formula, respectively. Above LAP, SV by PC-CMR showed no significant dependence on image-plane-position and correlated strongly with volumetry (rho: 0.633, p < 0.001, marginal-mean-difference (MMD): 1 ml, 95 % confidence-interval (CI): -4 to 6). AVA assessed in image-planes 0-10 mm above LAP differed significantly from invasive measurement (MMD: -0.14 cm2, 95 %CI: 0.08-0.21). In contrast, AVA-values by PC-CMR measured 10-20 mm above LAP showed good agreement with invasive determination without significant MMD (0.003 cm2, 95 %CI: -0.09 to 0.09). Within these measurements, a plane 15 mm above LAP resulted in the lowest bias (MMD: 0.02 cm2, 95 %CI:-0.29 to 0.33). SV and AVA via TTE correlated moderately with volumetry (rho: 0.461, p < 0.001; bias: 15 ml, p < 0.001) and cardiac catheterization (rho: 0.486, p < 0.001, bias: -0.13 cm2, p < 0.001), respectively. CONCLUSION PC-CMR measurements at 0-10 mm above LAP should be avoided due to significant AVA-overestimation compared to invasive determination. AVA-assessment by PC-CMR between 10 and 20 mm above LAP did not differ from invasive measurements, with the lowest intermethodical bias measured 15 mm above LAP.
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Affiliation(s)
- Felix Troger
- University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Christina Tiller
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Martin Reindl
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Ivan Lechner
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Magdalena Holzknecht
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Mathias Pamminger
- University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Paulina Poskaite
- University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Christian Kremser
- University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Hanno Ulmer
- Department for Medical Statistics, Informatics and Health Economics, Medical University of Innsbruck, Schoepfstrasse 41/1, 6020 Innsbruck, Austria
| | - Elke Ruth Gizewski
- University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Axel Bauer
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Sebastian Reinstadler
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Bernhard Metzler
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Gert Klug
- University Clinic of Internal Medicine III, Cardiology and Angiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Agnes Mayr
- University Clinic of Radiology, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
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The Role of Cardiac Magnetic Resonance in Aortic Stenosis and Regurgitation. J Cardiovasc Dev Dis 2022; 9:jcdd9040108. [PMID: 35448084 PMCID: PMC9030119 DOI: 10.3390/jcdd9040108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 03/23/2022] [Accepted: 03/28/2022] [Indexed: 02/06/2023] Open
Abstract
Cardiac magnetic resonance (CMR) imaging is a well-set diagnostic technique for assessment of valvular heart diseases and is gaining ground in current clinical practice. It provides high-quality images without the administration of ionizing radiation and occasionally without the need of contrast agents. It offers the unique possibility of a comprehensive stand-alone assessment of the heart including biventricular function, left ventricle remodeling, myocardial fibrosis, and associated valvulopathies. CMR is the recognized reference for the quantification of ventricular volumes, mass, and function. A particular strength is the ability to quantify flow, especially with new techniques which allow accurate measurement of stenosis and regurgitation. Furthermore, tissue mapping enables the visualization and quantification of structural changes in the myocardium. In this way, CMR has the potential to yield important prognostic information predicting those patients who will progress to surgery and impact outcomes. In this review, the fundamentals of CMR in assessment of aortic valve diseases (AVD) are described, together with its strengths and weaknesses. This state-of-the-art review provides an updated overview of CMR potentials in all AVD issues, including valve anatomy, flow quantification, ventricular volumes and function, and tissue characterization.
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Alattar Y, Soulat G, Gencer U, Messas E, Bollache E, Kachenoura N, Mousseaux E. Left ventricular diastolic early and late filling quantified from 4D flow magnetic resonance imaging. Diagn Interv Imaging 2022; 103:345-352. [DOI: 10.1016/j.diii.2022.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 01/17/2022] [Accepted: 02/09/2022] [Indexed: 01/02/2023]
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Guzzetti E, Racine HP, Tastet L, Shen M, Larose E, Clavel MA, Pibarot P, Beaudoin J. Accuracy of stroke volume measurement with phase-contrast cardiovascular magnetic resonance in patients with aortic stenosis. J Cardiovasc Magn Reson 2021; 23:124. [PMID: 34732204 PMCID: PMC8567621 DOI: 10.1186/s12968-021-00814-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 09/13/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Phase contrast (PC) cardiovascular magnetic resonance (CMR) in the ascending aorta (AAo) is widely used to calculate left ventricular (LV) stroke volume (SV). The accuracy of PC CMR may be altered by turbulent flow. Measurement of SV at another site is suggested in the presence of aortic stenosis, but very few data validates the accuracy or inaccuracy of PC in that setting. Our objective is to compare flow measurements obtained in the AAo and LV outflow tract (LVOT) in patients with aortic stenosis. METHODS Retrospective analysis of patients with aortic stenosis who had CMR and echocardiography. Patients with mitral regurgitation were excluded. PC in the AAo and LVOT were acquired to derive SV. LV SV from end-systolic and end-diastolic tracings was used as the reference measure. A difference ≥ 10% between the volumetric method and PC derived SVs was considered discordant. Metrics of turbulence and jet eccentricity were assessed to explore the predictors of discordant measurements. RESULTS We included 88 patients, 41% with bicuspid aortic valve. LVOT SV was concordant with the volumetric method in 79 (90%) patients vs 52 (59%) patients for AAo SV (p = 0.015). In multivariate analysis, aortic stenosis flow jet angle was a strong predictor of discordant measurement in the AAo (p = 0.003). Mathematical correction for the jet angle improved the concordance from 59 to 91%. Concordance was comparable in patients with bicuspid and trileaflet valves (57% and 62% concordance respectively; p = 0.11). Accuracy of SV measured in the LVOT was not influenced by jet eccentricity. For aortic regurgitation quantification, PC in the AAo had better correlation to volumetric assessments than LVOT PC. CONCLUSION LVOT PC SV in patients with aortic stenosis and eccentric jet might be more accurate compared to the AAo SV. Mathematical correction for the jet angle in the AAo might be another alternative to improve accuracy.
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Affiliation(s)
- Ezequiel Guzzetti
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada
| | - Hugo-Pierre Racine
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada
| | - Lionel Tastet
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada
| | - Mylène Shen
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada
| | - Eric Larose
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada
| | - Marie-Annick Clavel
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada
| | - Philippe Pibarot
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada
| | - Jonathan Beaudoin
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V-4G5, Canada.
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Xu K, Wang XD, Yang ZG, Xu HY, Xu R, Xie LJ, Wen LY, Fu H, Yan WF, Guo YK. Quantification of peak blood flow velocity at the cardiac valve and great thoracic vessels by four-dimensional flow and two-dimensional phase-contrast MRI compared with echocardiography: a systematic review and meta-analysis. Clin Radiol 2021; 76:863.e1-863.e10. [PMID: 34404516 DOI: 10.1016/j.crad.2021.07.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 07/15/2021] [Indexed: 02/08/2023]
Abstract
AIM To objectively examine the agreement and correlation between four-dimensional (4D) flow magnetic resonance imaging (MRI) and traditional two-dimensional (2D) phase-contrast (PC) MRI with the reference standard of Doppler echocardiography for measuring peak blood velocity at the cardiac valve and great arteries, and to assess if 4D flow MRI offers an advantage over the traditional 2D method. MATERIALS AND METHODS The literature was searched systematically for studies that evaluate the degree of correlation and agreement between 4D flow MRI or 2D PC MRI and Doppler retrieved from PubMed, EMBASE, and the Cochrane Library. A meta-analysis was conducted to determine the peak velocity pooled bias with 95% limits of agreement (LoA) and correlation coefficient (r) for 4D flow MRI and 2D PC MRI compared with Doppler. RESULTS Ten studies that compared 4D flow MRI with Doppler and 12 studies that compared 2D PC MRI with Doppler were included. 4D flow MRI showed an underestimation with bias and 95% LoA of -0.09 (-0.41, 0.24) m/s (p=0.079) while 2D PC MRI showed a poorer agreement with a bias and 95% LoA of -0.25 (-0.53, 0.03), p=0.596. 4D flow MRI and 2D PC MRI showed a strong correlation with R=0.80 (95% CI 0.75, 0.84; p<0.001) and R=0.83 (95% CI 0.79, 0.87; p<0.001), respectively. CONCLUSION In this meta-analysis, 4D flow MRI provides improved assessment of peak velocity when compared with traditional 2D PC MRI. 4D flow MRI can be considered an important complement or substitute to Doppler echocardiography for peak velocity assessment.
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Affiliation(s)
- K Xu
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - X D Wang
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Z G Yang
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - H Y Xu
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - R Xu
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - L J Xie
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - L Y Wen
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - H Fu
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - W F Yan
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Y K Guo
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China.
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Hohri Y, Itatani K, Matsuo A, Komori Y, Okamoto T, Goto T, Kobayashi T, Hiramatsu T, Miyazaki S, Nishino T, Yaku H. Estimating the Haemodynamic Streamline Vena Contracta as the Effective Orifice Area Measured from Reconstructed Multislice Phase-contrast MR Images for Patients with Moderately Accelerated Aortic Stenosis. Magn Reson Med Sci 2021; 21:569-582. [PMID: 34334586 DOI: 10.2463/mrms.mp.2021-0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE In aortic stenosis (AS), the discrepancy between moderately accelerated flow and effective orifice area (EOA) continues to pose a challenge. We developed a method of measuring the vena contracta area as hemodynamic EOA using cardiac MRI focusing on AS patients with a moderately accelerated flow to solve the problem that AS severity can currently be determined only by echocardiography. METHODS We investigated 40 patients with a peak transvalvular velocity > 3.0 m/s on transthoracic echocardiography (TTE). The patients were divided into highly accelerated and moderately accelerated AS groups according to whether or not the peak transvalvular velocity was ≥ 4.0 m/s. From the multislice 2D cine phase-contrast MRI data, the cross-sectional area of the vena contracta of the reconstructed streamline in the Valsalva sinus was defined as MRI-EOAs. Patient symptoms and echocardiography data, including EOA (defined as TTE-EOA), were derived from the continuity equation using TTE. RESULTS All participants in the highly accelerated AS group (n = 19) showed a peak velocity ≥ 4.0 m/s in MRI. Eleven patients in the moderately accelerated AS group (n = 21) had a TTE-EOA < 1.00 cm2. In the moderately accelerated AS group, MRI-EOAs demonstrated a strong correlation with TTE-EOAs (r = 0.76, P < 0.01). Meanwhile, in the highly accelerated AS group, MRI-EOAs demonstrated positivity but a moderate correlation with TTE-EOAs (r = 0.63, P = 0.004). MRI-EOAs were overestimated compared to TTE-EOAs. In terms of the moderately accelerated AS group, the best cut-off value for MRI-EOAs was < 1.23 cm2, compatible with TTE-EOAs < 1.00 cm2, with an excellent prediction of the New York Heart Association classification ≥ III (sensitivity 87.5%, specificity 76.9%). CONCLUSION MRI-EOAs may be an alternative to conventional echocardiography for patients with moderately accelerated AS, especially those with discordant echocardiographic parameters.
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Affiliation(s)
- Yu Hohri
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine
| | | | - Akiko Matsuo
- Department of Cardiology, Japanese Red Cross Kyoto Daini Hospital
| | | | - Takeshi Okamoto
- Department of Radiology, Japanese Red Cross Kyoto Daini Hospital
| | - Tomoyuki Goto
- Department of Cardiovascular Surgery, Japanese Red Cross Kyoto Daini Hospital
| | - Takuma Kobayashi
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine
| | - Takeshi Hiramatsu
- Department of Cardiovascular Surgery, Tokyo Women's Medical University Yachiyo Medical Center
| | | | | | - Hitoshi Yaku
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine
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Woldendorp K, Bannon PG, Grieve SM. Evaluation of aortic stenosis using cardiovascular magnetic resonance: a systematic review & meta-analysis. J Cardiovasc Magn Reson 2020; 22:45. [PMID: 32536342 PMCID: PMC7294634 DOI: 10.1186/s12968-020-00633-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 05/08/2020] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND As the average age of patients with severe aortic stenosis (AS) who receive procedural intervention continue to age, the need for non-invasive modalities that provide accurate diagnosis and operative planning is increasingly important. Advances in cardiovascular magnetic resonance (CMR) over the past two decades mean it is able to provide haemodynamic data at the aortic valve, along with high fidelity anatomical imaging. METHODS Electronic databases were searched for studies comparing CMR to transthoracic echocardiography (TTE) and transoesophageal echocardiography (TEE) in the diagnosis of AS. Studies were included only if direct comparison was made on matched patients, and if diagnosis was primarily through measurement of aortic valve area (AVA). RESULTS Twenty-three relevant, prospective articles were included in the meta-analysis, totalling 1040 individual patients. There was no significant difference in AVA measured as by CMR compared to TEE. CMR measurements of AVA size were larger compared to TTE by an average of 10.7% (absolute difference: + 0.14cm2, 95% CI 0.07-0.21, p < 0.001). Reliability was high for both inter- and intra-observer measurements (0.03cm2 +/- 0.04 and 0.02cm2 +/- 0.01, respectively). CONCLUSIONS Our analysis demonstrates the equivalence of AVA measurements using CMR compared to those obtained using TEE. CMR demonstrated a small but significantly larger AVA than TTE. However, this can be attributed to known errors in derivation of left ventricular outflow tract size as measured by TTE. By offering additional anatomical assessment, CMR is warranted as a primary tool in the assessment and workup of patients with severe AS who are candidates for surgical or transcatheter intervention.
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Affiliation(s)
- Kei Woldendorp
- Sydney Translational Imaging Laboratory, Imaging and Phenotyping Laboratory, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006 Australia
- Sydney Medical School, The University of Sydney, Camperdown, NSW 2050 Australia
- Baird Institute of Applied Heart & Lung Surgical Research, Newtown, NSW 2042 Australia
- Department of Cardiothoracic Surgery, Royal Prince Alfred Hospital, Camperdown, NSW 2006 Australia
| | - Paul G. Bannon
- Sydney Translational Imaging Laboratory, Imaging and Phenotyping Laboratory, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006 Australia
- Sydney Medical School, The University of Sydney, Camperdown, NSW 2050 Australia
- Baird Institute of Applied Heart & Lung Surgical Research, Newtown, NSW 2042 Australia
| | - Stuart M. Grieve
- Sydney Translational Imaging Laboratory, Imaging and Phenotyping Laboratory, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006 Australia
- Sydney Medical School, The University of Sydney, Camperdown, NSW 2050 Australia
- Department of Radiology, Royal Prince Alfred Hospital, Camperdown, NSW 2006 Australia
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Dillinger H, Walheim J, Kozerke S. On the limitations of echo planar 4D flow MRI. Magn Reson Med 2020; 84:1806-1816. [PMID: 32212352 DOI: 10.1002/mrm.28236] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 02/06/2020] [Accepted: 02/07/2020] [Indexed: 01/09/2023]
Abstract
PURPOSE To compare EPI and GRE readout in high-flow velocity regimes and evaluate their impact on measurement accuracy in silico and in vitro. THEORY AND METHODS Phase-contrast sequences for EPI and GRE were simulated using CFD velocity data to assess displacement artifacts as well as effective spatial resolution. In silico findings were validated experimentally using a steady flow phantom. RESULTS For EPI factor 5 and simulated stenotic flow with peak velocity of 2.2 m s - 1 , displacement artifacts resulted in misregistration of 7.3 mm at echo time and the effective resolution was locally reduced by factors 5 and 8 compared to GRE for flow along phase and frequency encoding directions, respectively. In vitro, a maximum velocity difference between EPI factor 5 and GRE of 0.97 m s - 1 was found. CONCLUSIONS Four-dimensional flow MRI using EPI readout results not only in considerable velocity misregistration but also in spatially varying degradation of resolution. The proposed work indicates that EPI is inferior to standard GRE for 4D flow MRI.
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Affiliation(s)
- Hannes Dillinger
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Jonas Walheim
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
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Zoghbi W, Adams D, Bonow R, Enriquez-Sarano M, Foster E, Grayburn P, Hahn R, Han Y, Hung J, Lang R, Little S, Shah D, Shernan S, Thavendiranathan P, Thomas J, Weissman N. Recommendations for noninvasive evaluation of native valvular regurgitation
A report from the american society of echocardiography developed in collaboration with the society for cardiovascular magnetic resonance. JOURNAL OF THE INDIAN ACADEMY OF ECHOCARDIOGRAPHY & CARDIOVASCULAR IMAGING 2020. [DOI: 10.4103/2543-1463.282191] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Extent of size, shape and systolic variability of the left ventricular outflow tract in aortic stenosis determined by phase-contrast MRI. Magn Reson Imaging 2018; 45:58-65. [DOI: 10.1016/j.mri.2017.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 03/20/2017] [Accepted: 09/01/2017] [Indexed: 11/21/2022]
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da Silveira JS, Smyke M, Rich AV, Liu Y, Jin N, Scandling D, Dickerson JA, Rochitte CE, Raman SV, Potter LC, Ahmad R, Simonetti OP. Quantification of aortic stenosis diagnostic parameters: comparison of fast 3 direction and 1 direction phase contrast CMR and transthoracic echocardiography. J Cardiovasc Magn Reson 2017; 19:35. [PMID: 28270219 PMCID: PMC5339981 DOI: 10.1186/s12968-017-0339-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/10/2017] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Aortic stenosis (AS) is a common valvular disorder, and disease severity is currently assessed by transthoracic echocardiography (TTE). However, TTE results can be inconsistent in some patients, thus other diagnostic modalities such as cardiovascular magnetic resonance (CMR) are demanded. While traditional unidirectional phase-contrast CMR (1Dir PC-CMR) underestimates velocity if the imaging plane is misaligned to the flow direction, multi-directional acquisitions are expected to improve velocity measurement accuracy. Nonetheless, clinical use of multidirectional techniques has been hindered by long acquisition times. Our goal was to quantify flow parameters in patients using 1Dir PC-CMR and a faster multi-directional technique (3Dir PC-CMR), and compare to TTE. METHODS Twenty-three patients were prospectively assessed with TTE and CMR. Slices above the aortic valve were acquired for both PC-CMR techniques and cine SSFP images were acquired to quantify left ventricular stroke volume. 3Dir PC-CMR implementation included a variable density sampling pattern with acceleration rate of 8 and a reconstruction method called ReVEAL, to significantly accelerate acquisition. 3Dir PC-CMR reconstruction was performed offline and ReVEAL-based image recovery was performed on the three (x, y, z) encoding pairs. 1Dir PC-CMR was acquired with GRAPPA acceleration rate of 2 and reconstructed online. CMR derived flow parameters and aortic valve area estimates were compared to TTE. RESULTS ReVEAL based 3Dir PC-CMR derived parameters correlated better with TTE than 1Dir PC-CMR. Correlations ranged from 0.61 to 0.81 between TTE and 1Dir PC-CMR and from 0.61 to 0.87 between TTE and 3Dir-PC-CMR. The correlation coefficients between TTE, 1Dir and 3Dir PC-CMR Vpeakwere 0.81 and 0.87, respectively. In comparison to ReVEAL, TTE slightly underestimates peak velocities, which is not surprising as TTE is only sensitive to flow that is parallel to the acoustic beam. CONCLUSIONS By exploiting structure unique to PC-CMR, ReVEAL enables multi-directional flow imaging in clinically feasible acquisition times. Results support the hypothesis that ReVEAL-based 3Dir PC-CMR provides better estimation of hemodynamic parameters in AS patients in comparison to 1Dir PC-CMR. While TTE can accurately measure velocity parallel to the acoustic beam, it is not sensitive to the other directions of flow. Therefore, multi-directional flow imaging, which encodes all three components of the velocity vector, can potentially outperform TTE in patients with eccentric or multiple jets.
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Affiliation(s)
- Juliana Serafim da Silveira
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
- InCor Heart Institute, University of São Paulo Medical School, São Paulo, SP, Brazil
| | - Matthew Smyke
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Adam V Rich
- Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH, USA
| | - Yingmin Liu
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Ning Jin
- Siemens Healthcare, Erlangen, Germany
| | - Debbie Scandling
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Jennifer A Dickerson
- Department of Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University, Columbus, OH, USA
| | - Carlos E Rochitte
- InCor Heart Institute, University of São Paulo Medical School, São Paulo, SP, Brazil
| | - Subha V Raman
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
- Department of Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University, Columbus, OH, USA
| | - Lee C Potter
- Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH, USA
| | - Rizwan Ahmad
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
- Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH, USA
| | - Orlando P Simonetti
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA.
- Department of Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University, Columbus, OH, USA.
- Department of Radiology, The Ohio State University, 460 W. 12th Avenue, room 320, 43210, Columbus, OH, USA.
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Richau J, Dieringer MA, Traber J, von Knobelsdorff-Brenkenhoff F, Greiser A, Schwenke C, Schulz-Menger J. Effects of heart valve prostheses on phase contrast flow measurements in Cardiovascular Magnetic Resonance - a phantom study. J Cardiovasc Magn Reson 2017; 19:5. [PMID: 28088917 PMCID: PMC5238524 DOI: 10.1186/s12968-016-0319-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Accepted: 12/21/2016] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Cardiovascular Magnetic Resonance is often used to evaluate patients after heart valve replacement. This study systematically analyses the influence of heart valve prostheses on phase contrast measurements in a phantom trial. METHODS Two biological and one mechanical aortic valve prostheses were integrated in a flow phantom. B0 maps and phase contrast measurements were acquired at a 1.5 T MR scanner using conventional gradient-echo sequences in predefined distances to the prostheses. Results were compared to measurements with a synthetic metal-free aortic valve. RESULTS The flow results at the level of the prosthesis differed significantly from the reference flow acquired before the level of the prosthesis. The maximum flow miscalculation was 154 ml/s for one of the biological prostheses and 140 ml/s for the mechanical prosthesis. Measurements with the synthetic aortic valve did not show significant deviations. Flow values measured approximately 20 mm distal to the level of the prosthesis agreed with the reference flow for all tested all prostheses. CONCLUSIONS The tested heart valve prostheses lead to a significant deviation of the measured flow rates compared to a reference. A distance of 20 mm was effective in our setting to avoid this influence.
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Affiliation(s)
- Johanna Richau
- Working Group on Cardiovascular Magnetic Resonance Imaging, Experimental and Clinical Research Center, joint cooperation of the Max-Delbrück-Centrum and Charité -Medical University Berlin, Berlin, Germany
| | | | - Julius Traber
- Working Group on Cardiovascular Magnetic Resonance Imaging, Experimental and Clinical Research Center, joint cooperation of the Max-Delbrück-Centrum and Charité -Medical University Berlin, Berlin, Germany
- HELIOS Klinikum Berlin-Buch, Department of Cardiology and Nephrology, Berlin, Germany
| | - Florian von Knobelsdorff-Brenkenhoff
- Working Group on Cardiovascular Magnetic Resonance Imaging, Experimental and Clinical Research Center, joint cooperation of the Max-Delbrück-Centrum and Charité -Medical University Berlin, Berlin, Germany
- HELIOS Klinikum Berlin-Buch, Department of Cardiology and Nephrology, Berlin, Germany
- Department of Cardiology, Clinic Agatharied, Ludwig-Maximilians-University Munich, Hausham, Germany
| | | | | | - Jeanette Schulz-Menger
- Working Group on Cardiovascular Magnetic Resonance Imaging, Experimental and Clinical Research Center, joint cooperation of the Max-Delbrück-Centrum and Charité -Medical University Berlin, Berlin, Germany.
- HELIOS Klinikum Berlin-Buch, Department of Cardiology and Nephrology, Berlin, Germany.
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Rodrigues J, Minhas K, Pieles G, McAlindon E, Occleshaw C, Manghat N, Hamilton M. The effect of reducing spatial resolution by in-plane partial volume averaging on peak velocity measurements in phase contrast magnetic resonance angiography. Quant Imaging Med Surg 2016; 6:564-572. [PMID: 27942477 DOI: 10.21037/qims.2016.10.06] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The aim of this study was to quantify the degree of the effect of in-plane partial volume averaging on recorded peak velocity in phase contrast magnetic resonance angiography (PCMRA). METHODS Using cardiac optimized 1.5 Tesla MRI scanners (Siemens Symphony and Avanto), 145 flow measurements (14 anatomical locations; ventricular outlets, aortic valve (AorV), aorta (5 sites), pulmonary arteries (3 sites), pulmonary veins, superior and inferior vena cava)- in 37 subjects (consisting of healthy volunteers, congenital and acquired heart disease patients) were analyzed by Siemens Argus default voxel averaging technique (where peak velocity = mean of highest velocity voxel and four neighbouring voxels) and by single voxel technique (1.3×1.3×5 or 1.7×1.7×5.5 mm3) (where peak velocity = highest velocity voxel only). The effect of scan protocol (breath hold versus free breathing) and scanner type (Siemens Symphony versus Siemens Avanto) were also assessed. Statistical significance was defined as P<0.05. RESULTS There was a significant mean increase in peak velocity of 7.1% when single voxel technique was used compared to voxel averaging (P<0.0001). Significant increases in peak velocity were observed by single voxel technique compared to voxel averaging regardless of subject type, anatomical flow location, scanner type and breathing command. Disabling voxel averaging did not affect the volume of flow recorded. CONCLUSIONS Reducing spatial resolution by the use of voxel averaging produces a significant underestimation of peak velocity. While this is of itself not surprising this is the first report to quantify the size of the effect. When PCMRA is used to assess peak velocity recording pixel averaging should be disabled.
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Affiliation(s)
- Jonathan Rodrigues
- Department of Clinical Radiology, Bristol Royal Infirmary, Marlborough Street, Bristol, UK
| | - Kishore Minhas
- Department of Clinical Radiology, Bristol Royal Infirmary, Marlborough Street, Bristol, UK
| | - Guido Pieles
- Department of Paediatric Cardiology, Royal Bristol Hospital for Children, Marlborough Street, Bristol, UK
| | - Elisa McAlindon
- Department of Cardiology, Bristol Royal Infirmary, Bristol, UK
| | - Christopher Occleshaw
- Department of Cardiology, Green Lane Cardiovascular Group, Auckland City Hospital, Auckland, New Zealand
| | - Nathan Manghat
- Department of Clinical Radiology, Bristol Royal Infirmary, Marlborough Street, Bristol, UK
| | - Mark Hamilton
- Department of Clinical Radiology, Bristol Royal Infirmary, Marlborough Street, Bristol, UK
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15
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Multimodality Noninvasive Imaging of Thoracic Aortic Aneurysms: Time to Standardize? Can J Cardiol 2016; 32:48-59. [DOI: 10.1016/j.cjca.2015.09.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 01/16/2023] Open
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16
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Kowallick JT, Steinmetz M, Schuster A, Unterberg-Buchwald C, Nguyen TT, Fasshauer M, Staab W, Hösch O, Rosenberg C, Paul T, Lotz J, Sohns JM. Non-invasive estimation of pulmonary outflow tract obstruction: A comparative study of cardiovascular phase contrast magnetic resonance and Doppler echocardiography versus cardiac catheterization. IJC HEART & VASCULATURE 2015; 10:1-7. [PMID: 28616508 PMCID: PMC5441337 DOI: 10.1016/j.ijcha.2015.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 11/02/2015] [Accepted: 11/03/2015] [Indexed: 10/26/2022]
Abstract
AIM To compare estimated pressure gradients from routine follow-up cardiovascular phase-contrast magnetic resonance (PC-MR) with those from Doppler echocardiography and invasive catheterization in patients with congenital heart disease (CHD) and pulmonary outflow tract obstruction. METHODS In 75 patients with pulmonary outflow tract obstruction maximal and mean PC-MR gradients were compared to maximal and mean Doppler gradients. Additionally, in a subgroup of 31 patients maximal and mean PC-MR and Doppler pressure gradients were compared to catheter peak-to-peak pressure gradients (PPG). RESULTS Maximal and mean PC-MR gradients underestimated pulmonary outflow tract obstruction as compared to Doppler (max gradient: bias = + 8.4 mm Hg (+ 47.6%), r = 0.89, p < 0.001; mean gradient: + 4.3 mm Hg (+ 49.0%), r = 0.88, p < 0.001). However, in comparison to catheter PPG, maximal PC-MR gradients (bias = + 1.8 mm Hg (+ 8.8%), r = 0.90, p = 0.14) and mean Doppler gradients (bias = - 2.3 mm Hg (- 11.2%), r = 0.87, p = 0.17) revealed best agreement. Mean PC-MR gradients underestimated (bias = - 7.7 mm Hg (- 55.6%), r = 0.90, p < 0.001) while maximal Doppler gradients systematically overestimated catheter PPG (bias = + 13.9 mm Hg (+ 56.5%), r = 0.88, p < 0.001). CONCLUSIONS Estimated maximal PC-MR pressure gradients from routine CHD follow-up agree well with invasively assessed peak-to-peak pressure gradients. Estimated maximal Doppler pressure gradients tend to overestimate, while Doppler mean gradients agree better with catheter PPG. Therefore, our data provide reasonable arguments to either apply maximal PC-MR gradients or mean Doppler gradients to non-invasively evaluate the severity of pulmonary outflow tract obstruction in the follow-up of CHD.
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Affiliation(s)
- Johannes Tammo Kowallick
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Michael Steinmetz
- Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Andreas Schuster
- Department of Cardiology and Pneumology, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Christina Unterberg-Buchwald
- Department of Cardiology and Pneumology, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Thuy-Trang Nguyen
- Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Centre Göttingen, Germany
| | - Martin Fasshauer
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Wieland Staab
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Olga Hösch
- Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Centre Göttingen, Germany
| | - Christina Rosenberg
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Germany
| | - Thomas Paul
- Department of Pediatric Cardiology and Intensive Care Medicine, University Medical Centre Göttingen, Germany
| | - Joachim Lotz
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Jan Martin Sohns
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
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17
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Looi JL, Kerr AJ, Gabriel R. Morphology of congenital and acquired aortic valve disease by cardiovascular magnetic resonance imaging. Eur J Radiol 2015; 84:2144-54. [DOI: 10.1016/j.ejrad.2015.07.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 06/14/2015] [Accepted: 07/15/2015] [Indexed: 10/23/2022]
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18
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Castets CR, Ribot EJ, Lefrançois W, Trotier AJ, Thiaudière E, Franconi JM, Miraux S. Fast and robust 3D T1 mapping using spiral encoding and steady RF excitation at 7 T: application to cardiac manganese enhanced MRI (MEMRI) in mice. NMR IN BIOMEDICINE 2015; 28:881-889. [PMID: 25989986 DOI: 10.1002/nbm.3327] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 03/19/2015] [Accepted: 04/16/2015] [Indexed: 06/04/2023]
Abstract
Mapping longitudinal relaxation times in 3D is a promising quantitative and non-invasive imaging tool to assess cardiac remodeling. Few methods are proposed in the literature allowing us to perform 3D T1 mapping. These methods often require long scan times and use a low number of 3D images to calculate T1 . In this project, a fast 3D T1 mapping method using a stack-of-spirals sampling scheme and regular RF pulse excitation at 7 T is presented. This sequence, combined with a newly developed fitting procedure, allowed us to quantify T1 of the whole mouse heart with a high spatial resolution of 208 × 208 × 315 µm(3) in 10-12 min acquisition time. The sensitivity of this method for measuring T1 variations was demonstrated on mouse hearts after several injections of manganese chloride (doses from 25 to 150 µmol kg(-1) ). T1 values were measured in vivo in both pre- and post-contrast experiments. This protocol was also validated on ischemic mice to demonstrate its efficiency to visualize tissue damage induced by a myocardial infarction. This study showed that combining spiral gradient shape and steady RF excitation enabled fast and robust 3D T1 mapping of the entire heart with a high spatial resolution.
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Affiliation(s)
- Charles R Castets
- Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536 CNRS/Universite de Bordeaux, Bordeaux Cedex, France
| | - Emeline J Ribot
- Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536 CNRS/Universite de Bordeaux, Bordeaux Cedex, France
| | - William Lefrançois
- Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536 CNRS/Universite de Bordeaux, Bordeaux Cedex, France
| | - Aurélien J Trotier
- Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536 CNRS/Universite de Bordeaux, Bordeaux Cedex, France
| | - Eric Thiaudière
- Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536 CNRS/Universite de Bordeaux, Bordeaux Cedex, France
| | - Jean-Michel Franconi
- Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536 CNRS/Universite de Bordeaux, Bordeaux Cedex, France
| | - Sylvain Miraux
- Centre de Resonance Magnetique des Systemes Biologiques, UMR 5536 CNRS/Universite de Bordeaux, Bordeaux Cedex, France
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19
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Lu JC, Nielsen JC, Morowitz L, Musani M, Ghadimi Mahani M, Agarwal PP, Ibrahim ESH, Dorfman AL. Use of a 1.0 Tesla open scanner for evaluation of pediatric and congenital heart disease: a retrospective cohort study. J Cardiovasc Magn Reson 2015; 17:39. [PMID: 26004027 PMCID: PMC4490663 DOI: 10.1186/s12968-015-0144-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 05/04/2015] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Open cardiovascular magnetic resonance (CMR) scanners offer the potential for imaging patients with claustrophobia or large body size, but at a lower 1.0 Tesla magnetic field. This study aimed to evaluate the efficacy of open CMR for evaluation of pediatric and congenital heart disease. METHODS This retrospective, cross-sectional study included all patients ≤18 years old or with congenital heart disease who underwent CMR on an open 1.0 Tesla scanner at two centers from 2012-2014. Indications for CMR and clinical questions were extracted from the medical record. Studies were qualitatively graded for image quality and diagnostic utility. In a subset of 25 patients, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were compared to size- and diagnosis-matched patients with CMR on a 1.5 Tesla scanner. RESULTS A total of 65 patients (median 17.3 years old, 60% male) were included. Congenital heart disease was present in 32 (50%), with tetralogy of Fallot and bicuspid aortic valve the most common diagnoses. Open CMR was used due to scheduling/equipment issues in 51 (80%), claustrophobia in 7 (11%), and patient size in 3 (5%); 4 patients with claustrophobia had failed CMR on a different scanner, but completed the study on open CMR without sedation. All patients had good or excellent image quality on black blood, phase contrast, magnetic resonance angiography, and late gadolinium enhancement imaging. There was below average image quality in 3/63 (5%) patients with cine images, and 4/15 (27%) patients with coronary artery imaging. SNR and CNR were decreased in cine and magnetic resonance angiography images compared to 1.5 Tesla. The clinical question was answered adequately in all but 2 patients; 1 patient with a Fontan had artifact from an embolization coil limiting RV volume analysis, and in 1 patient the right coronary artery origin was not well seen. CONCLUSIONS Open 1.0 Tesla scanners can effectively evaluate pediatric and congenital heart disease, including patients with claustrophobia and larger body size. Despite minor artifacts and differences in SNR and CNR, the majority of clinical questions can be answered adequately, with some limitations with coronary artery imaging. Further evaluation is necessary to optimize protocols and image quality.
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Affiliation(s)
- Jimmy C Lu
- Department of Pediatrics and Communicable Diseases, Division of Pediatric Cardiology, University of Michigan, Ann Arbor, MI, USA.
- Department of Radiology, Section of Pediatric Radiology, University of Michigan, Ann Arbor, MI, USA.
| | - James C Nielsen
- Departments of Pediatrics and Radiology, Stony Brook University, Stony Brook, NY, USA.
| | - Layne Morowitz
- Departments of Pediatrics and Radiology, Stony Brook University, Stony Brook, NY, USA.
| | - Muzammil Musani
- Department of Medicine, Division of Cardiology, Stony Brook University, Stony Brook, NY, USA.
| | - Maryam Ghadimi Mahani
- Department of Radiology, Section of Pediatric Radiology, University of Michigan, Ann Arbor, MI, USA.
| | - Prachi P Agarwal
- Department of Radiology, Division of Cardiothoracic Radiology, University of Michigan, Ann Arbor, MI, USA.
| | - El-Sayed H Ibrahim
- Department of Radiology, Division of Cardiothoracic Radiology, University of Michigan, Ann Arbor, MI, USA.
| | - Adam L Dorfman
- Department of Pediatrics and Communicable Diseases, Division of Pediatric Cardiology, University of Michigan, Ann Arbor, MI, USA.
- Department of Radiology, Section of Pediatric Radiology, University of Michigan, Ann Arbor, MI, USA.
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20
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Negahdar MJ, Kadbi M, Kendrick M, Stoddard MF, Amini AA. 4D spiral imaging of flows in stenotic phantoms and subjects with aortic stenosis. Magn Reson Med 2015; 75:1018-29. [PMID: 25914199 DOI: 10.1002/mrm.25636] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 12/17/2014] [Accepted: 01/05/2015] [Indexed: 11/09/2022]
Abstract
PURPOSE The utility of four-dimensional (4D) spiral flow in imaging of stenotic flows in both phantoms and human subjects with aortic stenosis is investigated. METHODS The method performs 4D flow acquisitions through a stack of interleaved spiral k-space readouts. Relative to conventional 4D flow, which performs Cartesian readout, the method has reduced echo time. Thus, reduced flow artifacts are observed when imaging high-speed stenotic flows. Four-dimensional spiral flow also provides significant savings in scan times relative to conventional 4D flow. RESULTS In vitro experiments were performed under both steady and pulsatile flows in a phantom model of severe stenosis (one inch diameter at the inlet, with 87% area reduction at the throat of the stenosis) while imaging a 6-cm axial extent of the phantom, which included the Gaussian-shaped stenotic narrowing. In all cases, gradient strength and slew rate for standard clinical acquisitions, and identical field of view and resolution were used. For low steady flow rates, quantitative and qualitative results showed a similar level of accuracy between 4D spiral flow (echo time [TE] = 2 ms, scan time = 40 s) and conventional 4D flow (TE = 3.6 ms, scan time = 1:01 min). However, in the case of high steady flow rates, 4D spiral flow (TE = 1.57 ms, scan time = 38 s) showed better visualization and accuracy as compared to conventional 4D flow (TE = 3.2 ms, scan time = 51 s). At low pulsatile flow rates, a good agreement was observed between 4D spiral flow (TE = 2 ms, scan time = 10:26 min) and conventional 4D flow (TE = 3.6 ms, scan time = 14:20 min). However, in the case of high flow-rate pulsatile flows, 4D spiral flow (TE = 1.57 ms, scan time = 10:26 min) demonstrated better visualization as compared to conventional 4D flow (TE = 3.2 ms, scan time = 14:20 min). The feasibility of 4D spiral flow was also investigated in five normal volunteers and four subjects with mild-to-moderate aortic stenosis. The approach achieved TE = 1.68 ms and scan time = 3:44 min. The conventional sequence achieved TE = 2.9 ms and scan time = 5:23 min. In subjects with aortic stenosis, we also compared both MRI methods with Doppler ultrasound (US) in the measurement of peak velocity, time to peak systolic velocity, and eject time. Bland-Altman analysis revealed that, when comparing peak velocities, the discrepancy between Doppler US and 4D spiral flow was significantly less than the discrepancy between Doppler and 4D Cartesian flow (2.75 cm/s vs. 10.25 cm/s), whereas the two MR methods were comparable (-5.75 s vs. -6 s) for time to peak. However, for the estimation of eject time, relative to Doppler US, the discrepancy for 4D conventional flow was smaller than that of 4D spiral flow (-16.25 s vs. -20 s). CONCLUSION Relative to conventional 4D flow, 4D spiral flow achieves substantial reductions in both the TE and scan times; therefore, utility for it should be sought in a variety of in vivo and complex flow imaging applications.
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Affiliation(s)
- M J Negahdar
- Medical Imaging Lab, Department of Electrical and Computer Engineering, University of Louisville, Louisville, Kentucky, USA.,Robley Rex Veterans Affairs Medical Center, Louisville, Kentucky, USA
| | - Mo Kadbi
- Philips Medical Systems, Philips Healthcare, Cleveland, Ohio, USA
| | - Michael Kendrick
- Robley Rex Veterans Affairs Medical Center, Louisville, Kentucky, USA
| | - Marcus F Stoddard
- Robley Rex Veterans Affairs Medical Center, Louisville, Kentucky, USA.,Division of Cardiovascular Medicine, University of Louisville, School of Medicine, Louisville, Kentucky, USA
| | - Amir A Amini
- Medical Imaging Lab, Department of Electrical and Computer Engineering, University of Louisville, Louisville, Kentucky, USA.,Robley Rex Veterans Affairs Medical Center, Louisville, Kentucky, USA
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Multimodality Imaging of Diseases of the Thoracic Aorta in Adults: From the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr 2015; 28:119-82. [DOI: 10.1016/j.echo.2014.11.015] [Citation(s) in RCA: 409] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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22
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Functional imaging of murine hearts using accelerated self-gated UTE cine MRI. Int J Cardiovasc Imaging 2014; 31:83-94. [DOI: 10.1007/s10554-014-0531-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/02/2014] [Indexed: 12/21/2022]
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23
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Quantification of congenital aortic valve stenosis in pediatric patients: comparison between cardiac magnetic resonance imaging and transthoracic echocardiography. Pediatr Cardiol 2014; 35:771-7. [PMID: 24343730 DOI: 10.1007/s00246-013-0851-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 11/28/2013] [Indexed: 10/25/2022]
Abstract
Previous studies showed the reliability of cardiac magnetic resonance imaging (cMRI) in the quantification of aortic valve stenosis in adults. The aim of this retrospective study was to assess the ability of cMRI in the quantification of congenital aortic valve stenosis (CAS) in children. Nineteen patients (mean age 14.0 ± 3.2 years, 15 boys and 4 girls) with CAS were imaged by cMRI and transthoracic echocardiography (TTE). cMRI was performed on a 1.5-Tesla MR scanner (Magnetom Avanto; Siemens Healthcare, Erlangen, Germany) using cine steady-state free precession sequences for the assessment of the aortic valve area (AVA) by MR planimetry and left-ventricular function. Phase-contrast measurement was used in cMRI to assess peak flow velocity above the aortic valve. A positive correlation was found between maximum systolic pressure gradient (MPG) as assessed by cMRI and TTE (28.9 ± 21.2 vs. 41.3 ± 22.7 mmHg, r = 0.84, p = 0.001) with a mean underestimation of 12.4 mmHg by cMRI. Only a weak correlation could be observed between AVA by cMRI and MPG at the aortic valve by TTE (r = -0.50, p = 0.029) and cMRI (r = -0.27, p = 0.40). Furthermore, a positive correlation between myocardial mass (cMRI) and MPG (TTE, r = 0.57, p = 0.01), but not between myocardial mass (cMRI) and AVA (cMRI, r = 0.07, p = 0.77), was found. The assessment of MPG by cMRI in patients with CAS is feasible with a trend toward underestimatation compared with TTE. Moreover, MPG seems to be a more accurate parameter than AVA regarding the prediction of myocardial hypertrophy.
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Nilsson A, Revstedt J, Heiberg E, Ståhlberg F, Bloch KM. Volumetric velocity measurements in restricted geometries using spiral sampling: a phantom study. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2014; 28:103-18. [PMID: 24838252 DOI: 10.1007/s10334-014-0449-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 03/28/2014] [Accepted: 04/24/2014] [Indexed: 10/25/2022]
Abstract
OBJECT The aim of this study was to evaluate the accuracy of maximum velocity measurements using volumetric phase-contrast imaging with spiral readouts in a stenotic flow phantom. MATERIALS AND METHODS In a phantom model, maximum velocity, flow, pressure gradient, and streamline visualizations were evaluated using volumetric phase-contrast magnetic resonance imaging (MRI) with velocity encoding in one (extending on current clinical practice) and three directions (for characterization of the flow field) using spiral readouts. Results of maximum velocity and pressure drop were compared to computational fluid dynamics (CFD) simulations, as well as corresponding low-echo-time (TE) Cartesian data. Flow was compared to 2D through-plane phase contrast (PC) upstream from the restriction. RESULTS Results obtained with 3D through-plane PC as well as 4D PC at shortest TE using a spiral readout showed excellent agreements with the maximum velocity values obtained with CFD (<1 % for both methods), while larger deviations were seen using Cartesian readouts (-2.3 and 13 %, respectively). Peak pressure drop calculations from 3D through-plane PC and 4D PC spiral sequences were respectively 14 and 13 % overestimated compared to CFD. CONCLUSION Identification of the maximum velocity location, as well as the accurate velocity quantification can be obtained in stenotic regions using short-TE spiral volumetric PC imaging.
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Affiliation(s)
- Anders Nilsson
- Department of Medical Radiation Physics, Lund University, Lund, Sweden,
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25
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Speiser U, Quick S, Haas D, Youssef A, Waessnig NK, Ibrahim K, Strasser RH, Schoen S. 3-T magnetic resonance for determination of aortic valve area: A comparison to echocardiography. SCAND CARDIOVASC J 2014; 48:176-83. [DOI: 10.3109/14017431.2014.906646] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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26
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Harvey JJ, Hoey ETD, Ganeshan A. Imaging of the aortic valve with MRI and CT angiography. Clin Radiol 2013; 68:1192-205. [PMID: 24034550 DOI: 10.1016/j.crad.2013.07.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/20/2013] [Accepted: 07/15/2013] [Indexed: 12/31/2022]
Abstract
The aortic valve may be affected by a wide range of congenital and acquired diseases. Echocardiography is the main non-invasive imaging technique for assessing patho-anatomical alterations of the aortic valve and adjacent structures and in many cases is sufficient to establish a diagnosis and/or guide treatment decisions. Recent technological advances in magnetic resonance imaging (MRI) and multidetector computed tomography (MDCT) have enabled these techniques to play a complimentary role in certain clinical scenarios and as such can be useful problem-solving tools. Radiologists should be familiar with the indications, advantages, and limitations of MRI and MDCT in order to advise and direct an appropriate imaging strategy depending upon the clinical scenario. This article reviews the role of MRI and MDCT angiography for assessment of the aortic valve including relevant anatomy, scan acquisition protocols, and post-processing methods. An approach to interpretation and the key imaging features of commonly encountered aortic valvular diseases are discussed.
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Affiliation(s)
- J J Harvey
- Department of Radiology and Royal Centre for Defence Medicine, Queen Elizabeth Hospital, Edgbaston, UK
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Muzzarelli S, Monney P, O'Brien K, Faletra F, Moccetti T, Vogt P, Schwitter J. Quantification of aortic flow by phase-contrast magnetic resonance in patients with bicuspid aortic valve. Eur Heart J Cardiovasc Imaging 2013; 15:77-84. [DOI: 10.1093/ehjci/jet129] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Hoerr V, Nagelmann N, Nauerth A, Kuhlmann MT, Stypmann J, Faber C. Cardiac-respiratory self-gated cine ultra-short echo time (UTE) cardiovascular magnetic resonance for assessment of functional cardiac parameters at high magnetic fields. J Cardiovasc Magn Reson 2013; 15:59. [PMID: 23826850 PMCID: PMC3707860 DOI: 10.1186/1532-429x-15-59] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 06/19/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To overcome flow and electrocardiogram-trigger artifacts in cardiovascular magnetic resonance (CMR), we have implemented a cardiac and respiratory self-gated cine ultra-short echo time (UTE) sequence. We have assessed its performance in healthy mice by comparing the results with those obtained with a self-gated cine fast low angle shot (FLASH) sequence and with echocardiography. METHODS 2D self-gated cine UTE (TE/TR = 314 μs/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 5 min 5 sec) and self-gated cine FLASH (TE/TR = 3 ms/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 4 min 49 sec) images were acquired at 9.4 T. Volume of the left and right ventricular (LV, RV) myocardium as well as the end-diastolic and -systolic volume was segmented manually in MR images and myocardial mass, stroke volume (SV), ejection fraction (EF) and cardiac output (CO) were determined. Statistical differences were analyzed by using Student t test and Bland-Altman analyses. RESULTS Self-gated cine UTE provided high quality images with high contrast-to-noise ratio (CNR) also for the RV myocardium (CNRblood-myocardium = 25.5 ± 7.8). Compared to cine FLASH, susceptibility, motion, and flow artifacts were considerably reduced due to the short TE of 314 μs. The aortic valve was clearly discernible over the entire cardiac cycle. Myocardial mass, SV, EF and CO determined by self-gated UTE were identical to the values measured with self-gated FLASH and showed good agreement to the results obtained by echocardiography. CONCLUSIONS Self-gated UTE allows for robust measurement of cardiac parameters of diagnostic interest. Image quality is superior to self-gated FLASH, rendering the method a powerful alternative for the assessment of cardiac function at high magnetic fields.
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Affiliation(s)
- Verena Hoerr
- Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | - Nina Nagelmann
- Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | | | | | - Jörg Stypmann
- Department of Cardiovascular Medicine, Division of Cardiology, University Hospital Muenster, Muenster, Germany
| | - Cornelius Faber
- Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
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Bennett CJ, Maleszewski JJ, Araoz PA. CT and MR imaging of the aortic valve: radiologic-pathologic correlation. Radiographics 2013; 32:1399-420. [PMID: 22977027 DOI: 10.1148/rg.325115727] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Valvular disease is estimated to account for as many as 20% of cardiac surgical procedures performed in the United States. It may be congenital in origin or secondary to another disease process. One congenital anomaly, bicuspid aortic valve, is associated with increased incidence of stenosis, regurgitation, endocarditis, and aneurysmal dilatation of the aorta. A bicuspid valve has two cusps instead of the normal three; resultant fusion or poor excursion of the valve leaflets may lead to aortic stenosis, the presence of which is signaled by dephasing jets on magnetic resonance (MR) images. Surgery is generally recommended for patients with severe stenosis who are symptomatic or who have significant ventricular dysfunction; transcatheter aortic valve implantation (TAVI) is an emerging therapeutic option for patients who are not eligible for surgical treatment. Computed tomography (CT) is an essential component of preoperative planning for TAVI; it is used to determine the aortic root dimensions, severity of peripheral vascular disease, and status of the coronary arteries. Aortic regurgitation, which is caused by incompetent closure of the aortic valve, likewise leads to the appearance of jets on MR images. The severity of regurgitation is graded on the basis of valvular morphologic parameters; qualitative assessment of dephasing jets at Doppler ultrasonography; or measurements of the regurgitant fraction, volume, and orifice area. Mild regurgitation is managed conservatively, whereas severe or symptomatic regurgitation usually leads to valve replacement surgery, especially in the presence of substantial left ventricular enlargement or dysfunction. Bacterial endocarditis, although less common than aortic stenosis and regurgitation, is associated with substantial morbidity and mortality. Electrocardiographically gated CT reliably demonstrates infectious vegetations and benign excrescences of 1 cm or more on the valve surface, allowing the assessment of any embolic complications.
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Nordmeyer S, Riesenkampff E, Messroghli D, Kropf S, Nordmeyer J, Berger F, Kuehne T. Four-dimensional velocity-encoded magnetic resonance imaging improves blood flow quantification in patients with complex accelerated flow. J Magn Reson Imaging 2012; 37:208-16. [PMID: 22976284 DOI: 10.1002/jmri.23793] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 07/27/2012] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To evaluate the use of four-dimensional (4D) velocity-encoded magnetic resonance imaging (VEC MRI) for blood flow quantification in patients with semilunar valve stenosis and complex accelerated flow. MATERIALS AND METHODS Peak velocities (Vmax) and stroke volumes (SV) were quantified by 2D and 4D VEC MRI in volunteers (n = 7) and patients with semilunar valve stenosis (n = 18). Measurements were performed above the aortic and pulmonary valve with both techniques and, additionally, at multiple predefined planes in the ascending aorta and in the pulmonary trunk within the 4D dataset. In patients, 4D VEC MRI streamline analysis identified flow patterns and regions of highest flow velocity (4D(max-targeted)) for further measurements and Vmax was also measured by Doppler-echocardiography. RESULTS In patients, 4D VEC MRI showed higher Vmax than 2D VEC MRI (2.7 ± 0.6 m/s vs. 2.4 ± 0.5 m/s, P < 0.03) and was more comparable to Doppler-echocardiography (2.8 ± 0.7 m/s). 4D(max-targeted) revealed highest Vmax values (3.1 ± 0.6 m/s). SV measurements showed significant differences between different anatomical levels in the ascending aorta in patients with complex accelerated flow, whereas differences in volunteers with laminar flow patterns were negligible (P = 0.004). CONCLUSION 4D VEC MRI improves MRI-derived blood flow quantification in patients with semilunar valve stenosis and complex accelerated flow.
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Affiliation(s)
- Sarah Nordmeyer
- Deutsches Herzzentrum Berlin, Unit of Cardiovascular Imaging, Department of Congenital Heart Disease and Pediatric Cardiology, Berlin, Germany.
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Defrance C, Bollache E, Kachenoura N, Perdrix L, Hrynchyshyn N, Bruguière E, Redheuil A, Diebold B, Mousseaux E. Evaluation of aortic valve stenosis using cardiovascular magnetic resonance: comparison of an original semiautomated analysis of phase-contrast cardiovascular magnetic resonance with Doppler echocardiography. Circ Cardiovasc Imaging 2012; 5:604-12. [PMID: 22798520 DOI: 10.1161/circimaging.111.971218] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Accurate quantification of aortic valve stenosis (AVS) is needed for relevant management decisions. However, transthoracic Doppler echocardiography (TTE) remains inconclusive in a significant number of patients. Previous studies demonstrated the usefulness of phase-contrast cardiovascular magnetic resonance (PC-CMR) in noninvasive AVS evaluation. We hypothesized that semiautomated analysis of aortic hemodynamics from PC-CMR might provide reproducible and accurate evaluation of aortic valve area (AVA), aortic velocities, and gradients in agreement with TTE. METHODS AND RESULTS We studied 53 AVS patients (AVA(TTE)=0.87±0.44 cm(2)) and 21 controls (AVA(TTE)=2.96±0.59 cm(2)) who had TTE and PC-CMR of aortic valve and left ventricular outflow tract on the same day. PC-CMR data analysis included left ventricular outflow tract and aortic valve segmentation, and extraction of velocities, gradients, and flow rates. Three AVA measures were performed: AVA(CMR1) based on Hakki formula, AVA(CMR2) based on continuity equation, AVA(CMR3) simplified continuity equation=left ventricular outflow tract peak flow rate/aortic peak velocity. Our analysis was reproducible, as reflected by low interoperator variability (<4.56±4.40%). Comparison of PC-CMR and TTE aortic peak velocities and mean gradients resulted in good agreement (r=0.92 with mean bias=-29±62 cm/s and r=0.86 with mean bias=-12±15 mm Hg, respectively). Although good agreement was found between TTE and continuity equation-based CMR-AVA (r>0.94 and mean bias=-0.01±0.38 cm(2) for AVA(CMR2), -0.09±0.28 cm(2) for AVA(CMR3)), AVA(CMR1) values were lower than AVA(TTE) especially for higher AVA (mean bias=-0.45±0.52 cm(2)). Besides, ability of PC-CMR to detect severe AVS, defined by TTE, provided the best results for continuity equation-based methods (accuracy >94%). CONCLUSIONS Our PC-CMR semiautomated AVS evaluation provided reproducible measurements that accurately detected severe AVS and were in good agreement with TTE.
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Affiliation(s)
- Carine Defrance
- INSERM U678/UPMC Universite Paris 6, Hôpital Européen Georges Pompidou, 20 Rue Leblanc, Paris, France
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Vogel-Claussen J, Santaularia Tomas M, Newatia A, Boyce D, Pinheiro A, Abraham R, Abraham T, Bluemke DA. Cardiac MRI evaluation of hypertrophic cardiomyopathy: left ventricular outflow tract/aortic valve diameter ratio predicts severity of LVOT obstruction. J Magn Reson Imaging 2012; 36:598-603. [PMID: 22549972 DOI: 10.1002/jmri.23677] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 03/16/2012] [Indexed: 01/10/2023] Open
Abstract
PURPOSE To evaluate if left ventricular outflow tract/aortic valve (LVOT/AO) diameter ratio measured by cardiac magnetic resonance (CMR) imaging is an accurate marker for LVOT obstruction in patients with hypertrophic cardiomyopathy (HCM) compared to Doppler echocardiography. MATERIALS AND METHODS In all, 92 patients with HCM were divided into three groups based on their resting echocardiographic LVOT pressure gradient (PG): <30 mmHg at rest (nonobstructive, n = 31), <30 mmHg at rest, >30 mmHg after provocation (latent, n = 29), and >30 mmHg at rest (obstructive, n = 32). The end-systolic dimension of the LVOT on 3-chamber steady-state free precession (SSFP) CMR was divided by the end diastolic aortic valve diameter to calculate the LVOT/AO diameter ratio. RESULTS There were significant differences in the LVOT/AO diameter ratio among the three subgroups (nonobstructive 0.60 ± 0.13, latent 0.41 ± 0.16, obstructive 0.24 ± 0.09, P < 0.001). There was a strong linear inverse correlation between the LVOT/AO diameter ratio and the log of the LVOT pressure gradient (r = -0.84, P < 0.001). For detection of a resting gradient >30 mmHg, the LVOT/AO diameter ratio the area under the receiver operating characteristic (ROC) curve was 0.91 (95% confidence interval [CI] 0.85-0.97). For detection of a resting and/or provoked gradient >30 mmHg, the LVOT/AO diameter ratio area under the ROC curve was 0.90 (95% CI 0.84-0.96). CONCLUSION The LVOT/AO diameter ratio is an accurate, reproducible, noninvasive, and easy to use CMR marker to assess LVOT pressure gradients in patients with HCM.
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Affiliation(s)
- Jens Vogel-Claussen
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
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Achenbach S, Barkhausen J, Beer M, Beerbaum P, Dill T, Eichhorn J, Fratz S, Gutberlet M, Hoffmann M, Huber A, Hunold P, Klein C, Krombach G, Kreitner KF, Kühne T, Lotz J, Maintz D, Marholdt H, Merkle N, Messroghli D, Miller S, Paetsch I, Radke P, Steen H, Thiele H, Sarikouch S, Fischbach R. Konsensusempfehlungen der DRG/DGK/DGPK zum Einsatz der Herzbildgebung mit Computertomographie und Magnetresonanztomographie. KARDIOLOGE 2012. [DOI: 10.1007/s12181-012-0417-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Kahlert P, Parohl N, Albert J, Schäfer L, Reinhardt R, Kaiser GM, McDougall I, Decker B, Plicht B, Erbel R, Eggebrecht H, Ladd ME, Quick HH. Towards real-time cardiovascular magnetic resonance guided transarterial CoreValve implantation: in vivo evaluation in swine. J Cardiovasc Magn Reson 2012; 14:21. [PMID: 22453050 PMCID: PMC3337256 DOI: 10.1186/1532-429x-14-21] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 03/27/2012] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Real-time cardiovascular magnetic resonance (rtCMR) is considered attractive for guiding TAVI. Owing to an unlimited scan plane orientation and an unsurpassed soft-tissue contrast with simultaneous device visualization, rtCMR is presumed to allow safe device navigation and to offer optimal orientation for precise axial positioning. We sought to evaluate the preclinical feasibility of rtCMR-guided transarterial aortic valve implatation (TAVI) using the nitinol-based Medtronic CoreValve bioprosthesis. METHODS rtCMR-guided transfemoral (n = 2) and transsubclavian (n = 6) TAVI was performed in 8 swine using the original CoreValve prosthesis and a modified, CMR-compatible delivery catheter without ferromagnetic components. RESULTS rtCMR using TrueFISP sequences provided reliable imaging guidance during TAVI, which was successful in 6 swine. One transfemoral attempt failed due to unsuccessful aortic arch passage and one pericardial tamponade with subsequent death occurred as a result of ventricular perforation by the device tip due to an operating error, this complication being detected without delay by rtCMR. rtCMR allowed for a detailed, simultaneous visualization of the delivery system with the mounted stent-valve and the surrounding anatomy, resulting in improved visualization during navigation through the vasculature, passage of the aortic valve, and during placement and deployment of the stent-valve. Post-interventional success could be confirmed using ECG-triggered time-resolved cine-TrueFISP and flow-sensitive phase-contrast sequences. Intended valve position was confirmed by ex-vivo histology. CONCLUSIONS Our study shows that rtCMR-guided TAVI using the commercial CoreValve prosthesis in conjunction with a modified delivery system is feasible in swine, allowing improved procedural guidance including immediate detection of complications and direct functional assessment with reduction of radiation and omission of contrast media.
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Affiliation(s)
- Philipp Kahlert
- Department of Cardiology, West-German Heart Center Essen, Essen University Hospital, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Nina Parohl
- Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen University Hospital, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Juliane Albert
- Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen University Hospital, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Lena Schäfer
- Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen University Hospital, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Renate Reinhardt
- Department of General, Visceral and Transplantation Surgery, Essen University Hospital, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Gernot M Kaiser
- Department of General, Visceral and Transplantation Surgery, Essen University Hospital, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Ian McDougall
- Evasc Medical Systems, 107-1099 West 8th Avenue, Vancouver, BC V6H 1C3, Canada
| | - Brad Decker
- Evasc Medical Systems, 107-1099 West 8th Avenue, Vancouver, BC V6H 1C3, Canada
| | - Björn Plicht
- Department of Cardiology, West-German Heart Center Essen, Essen University Hospital, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Raimund Erbel
- Department of Cardiology, West-German Heart Center Essen, Essen University Hospital, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Holger Eggebrecht
- Department of Cardiology, West-German Heart Center Essen, Essen University Hospital, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Mark E Ladd
- Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen University Hospital, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Harald H Quick
- Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen University Hospital, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
- Institute of Medical Physics, Friedrich-Alexander-University Erlangen-Nürnberg, Henkestrasse 91, 91052 Erlangen, Germany
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Pennell DJ, Firmin DN, Kilner PJ, Manning WJ, Mohiaddin RH, Prasad SK. Review of journal of cardiovascular magnetic resonance 2010. J Cardiovasc Magn Reson 2011; 13:48. [PMID: 21914185 PMCID: PMC3182946 DOI: 10.1186/1532-429x-13-48] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 09/13/2011] [Indexed: 12/15/2022] Open
Abstract
There were 75 articles published in the Journal of Cardiovascular Magnetic Resonance (JCMR) in 2010, which is a 34% increase in the number of articles since 2009. The quality of the submissions continues to increase, and the editors were delighted with the recent announcement of the JCMR Impact Factor of 4.33 which showed a 90% increase since last year. Our acceptance rate is approximately 30%, but has been falling as the number of articles being submitted has been increasing. In accordance with Open-Access publishing, the JCMR articles go on-line as they are accepted with no collating of the articles into sections or special thematic issues. Last year for the first time, the Editors summarized the papers for the readership into broad areas of interest or theme, which we felt would be useful to practitioners of cardiovascular magnetic resonance (CMR) so that you could review areas of interest from the previous year in a single article in relation to each other and other recent JCMR articles 1. This experiment proved very popular with a very high rate of downloading, and therefore we intend to continue this review annually. The papers are presented in themes and comparison is drawn with previously published JCMR papers to identify the continuity of thought and publication in the journal. We hope that you find the open-access system increases wider reading and citation of your papers, and that you will continue to send your quality manuscripts to JCMR for publication.
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Affiliation(s)
- Dudley J Pennell
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK
- National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ, UK
| | - David N Firmin
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK
- National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ, UK
| | - Philip J Kilner
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK
- National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ, UK
| | - Warren J Manning
- Department of Medicine (Cardiovascular Division) and Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 USA
- Harvard Medical School, 25 Shattuck Street, Boston, MA 02115 USA
| | - Raad H Mohiaddin
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK
- National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ, UK
| | - Sanjay K Prasad
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK
- National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ, UK
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Garcia J, Kadem L, Larose E, Clavel MA, Pibarot P. Comparison between cardiovascular magnetic resonance and transthoracic Doppler echocardiography for the estimation of effective orifice area in aortic stenosis. J Cardiovasc Magn Reson 2011; 13:25. [PMID: 21527021 PMCID: PMC3108925 DOI: 10.1186/1532-429x-13-25] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Accepted: 04/28/2011] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The effective orifice area (EOA) estimated by transthoracic Doppler echocardiography (TTE) via the continuity equation is commonly used to determine the severity of aortic stenosis (AS). However, there are often discrepancies between TTE-derived EOA and invasive indices of stenosis, thus raising uncertainty about actual definite severity. Cardiovascular magnetic resonance (CMR) has emerged as an alternative method for non-invasive estimation of valve EOA. The objective of this study was to assess the concordance between TTE and CMR for the estimation of valve EOA. METHODS AND RESULTS 31 patients with mild to severe AS (EOA range: 0.72 to 1.73 cm2) and seven (7) healthy control subjects with normal transvalvular flow rate underwent TTE and velocity-encoded CMR. Valve EOA was calculated by the continuity equation. CMR revealed that the left ventricular outflow tract (LVOT) cross-section is typically oval and not circular. As a consequence, TTE underestimated the LVOT cross-sectional area (ALVOT, 3.84 ± 0.80 cm2) compared to CMR (4.78 ± 1.05 cm2). On the other hand, TTE overestimated the LVOT velocity-time integral (VTILVOT: 21 ± 4 vs. 15 ± 4 cm). Good concordance was observed between TTE and CMR for estimation of aortic jet VTI (61 ± 22 vs. 57 ± 20 cm). Overall, there was a good correlation and concordance between TTE-derived and CMR-derived EOAs (1.53 ± 0.67 vs. 1.59 ± 0.73 cm2, r = 0.92, bias = 0.06 ± 0.29 cm2). The intra- and inter- observer variability of TTE-derived EOA was 5 ± 5% and 9 ± 5%, respectively, compared to 2 ± 1% and 7 ± 5% for CMR-derived EOA. CONCLUSION Underestimation of ALVOT by TTE is compensated by overestimation of VTILVOT, thereby resulting in a good concordance between TTE and CMR for estimation of aortic valve EOA. CMR was associated with less intra- and inter- observer measurement variability compared to TTE. CMR provides a non-invasive and reliable alternative to Doppler-echocardiography for the quantification of AS severity.
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Affiliation(s)
- Julio Garcia
- Québec Heart and Lung Institute, Laval University, Québec, Canada
- Laboratory of Cardiovascular Fluid Dynamics, Concordia University, Montréal, Canada
| | - Lyes Kadem
- Laboratory of Cardiovascular Fluid Dynamics, Concordia University, Montréal, Canada
| | - Eric Larose
- Québec Heart and Lung Institute, Laval University, Québec, Canada
| | | | - Philippe Pibarot
- Québec Heart and Lung Institute, Laval University, Québec, Canada
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Nordmeyer S, Riesenkampff E, Crelier G, Khasheei A, Schnackenburg B, Berger F, Kuehne T. Flow-sensitive four-dimensional cine magnetic resonance imaging for offline blood flow quantification in multiple vessels: a validation study. J Magn Reson Imaging 2011; 32:677-83. [PMID: 20815066 DOI: 10.1002/jmri.22280] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
PURPOSE To further validate the quantitative use of flow-sensitive four-dimensional velocity encoded cine magnetic resonance imaging (4D VEC MRI) for simultaneously acquired venous and arterial blood flow in healthy volunteers and for abnormal flow in patients with congenital heart disease. MATERIALS AND METHODS Stroke volumes (SV) obtained in arterial and venous thoracic vessels were compared between standard two-dimensional (2D), 4D VEC MRI with and without respiratory navigator gating (gated/nongated) in volunteers (n = 7). In addition, SV and regurgitation fractions (RF) measured in aorta or pulmonary trunk of patients with malformed and/or insufficient valves (n = 10) were compared between 2D and nongated 4D VEC MRI methods. RESULTS In volunteers and patients, Bland-Altman tests showed excellent agreement between 2D, gated, and nongated 4D VEC MRI obtained quantitative blood flow measurements. The bias between 2D and gated 4D VEC MRI was <0.5 mL for SV; between 2D and nongated 4D VEC MRI the bias was <0.7 mL for SV and <1% for RF. CONCLUSION Blood flow can be quantified accurately in arterial, venous, and pathological flow conditions using 4D VEC MRI. Nongated 4D VEC MRI has the potential to be suited for clinical use in patients with congenital heart disease who require flow acquisitions in multiple vessels.
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Affiliation(s)
- Sarah Nordmeyer
- Deutsches Herzzentrum Berlin, Unit of Cardiovascular Imaging, Department of Congenital Heart Disease and Paediatric Cardiology, Berlin, Germany.
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Kahlert P, Eggebrecht H, Plicht B, Kraff O, McDougall I, Decker B, Erbel R, Ladd ME, Quick HH. Towards real-time cardiovascular magnetic resonance-guided transarterial aortic valve implantation: in vitro evaluation and modification of existing devices. J Cardiovasc Magn Reson 2010; 12:58. [PMID: 20942968 PMCID: PMC2964701 DOI: 10.1186/1532-429x-12-58] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2010] [Accepted: 10/13/2010] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Cardiovascular magnetic resonance (CMR) is considered an attractive alternative for guiding transarterial aortic valve implantation (TAVI) featuring unlimited scan plane orientation and unsurpassed soft-tissue contrast with simultaneous device visualization. We sought to evaluate the CMR characteristics of both currently commercially available transcatheter heart valves (Edwards SAPIEN™, Medtronic CoreValve®) including their dedicated delivery devices and of a custom-built, CMR-compatible delivery device for the Medtronic CoreValve® prosthesis as an initial step towards real-time CMR-guided TAVI. METHODS The devices were systematically examined in phantom models on a 1.5-Tesla scanner using high-resolution T1-weighted 3D FLASH, real-time TrueFISP and flow-sensitive phase-contrast sequences. Images were analyzed for device visualization quality, device-related susceptibility artifacts, and radiofrequency signal shielding. RESULTS CMR revealed major susceptibility artifacts for the two commercial delivery devices caused by considerable metal braiding and precluding in vivo application. The stainless steel-based Edwards SAPIEN™ prosthesis was also regarded not suitable for CMR-guided TAVI due to susceptibility artifacts exceeding the valve's dimensions and hindering an exact placement. In contrast, the nitinol-based Medtronic CoreValve® prosthesis was excellently visualized with delineation even of small details and, thus, regarded suitable for CMR-guided TAVI, particularly since reengineering of its delivery device toward CMR-compatibility resulted in artifact elimination and excellent visualization during catheter movement and valve deployment on real-time TrueFISP imaging. Reliable flow measurements could be performed for both stent-valves after deployment using phase-contrast sequences. CONCLUSIONS The present study shows that the Medtronic CoreValve® prosthesis is potentially suited for real-time CMR-guided placement in vivo after suggested design modifications of the delivery system.
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Affiliation(s)
- Philipp Kahlert
- Department of Cardiology, West-German Heart Center Essen, University Hospital Essen, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Holger Eggebrecht
- Department of Cardiology, West-German Heart Center Essen, University Hospital Essen, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Björn Plicht
- Department of Cardiology, West-German Heart Center Essen, University Hospital Essen, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Oliver Kraff
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Ian McDougall
- Evasc Medical Systems, 107-1099 West 8th Avenue, Vancouver, BC V6H 1C3, Canada
| | - Brad Decker
- Evasc Medical Systems, 107-1099 West 8th Avenue, Vancouver, BC V6H 1C3, Canada
| | - Raimund Erbel
- Department of Cardiology, West-German Heart Center Essen, University Hospital Essen, University Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Mark E Ladd
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Harald H Quick
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
- Institute of Medical Physics, Friedrich-Alexander University Erlangen-Nürnberg, Henkestrasse 91, 91052 Erlangen, Germany
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Current awareness in NMR in biomedicine. NMR IN BIOMEDICINE 2010; 23:651-658. [PMID: 20684066 DOI: 10.1002/nbm.1454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Flow and Valvular Disease Studied by Cardiovascular Magnetic Resonance. CURRENT CARDIOVASCULAR IMAGING REPORTS 2010. [DOI: 10.1007/s12410-010-9008-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Pennell DJ, Firmin DN, Kilner PJ, Manning WJ, Mohiaddin RH, Neubauer S, Prasad SK. Review of Journal of Cardiovascular Magnetic Resonance 2009. J Cardiovasc Magn Reson 2010; 12:15. [PMID: 20302618 PMCID: PMC2847562 DOI: 10.1186/1532-429x-12-15] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Accepted: 03/19/2010] [Indexed: 11/10/2022] Open
Abstract
There were 56 articles published in the Journal of Cardiovascular Magnetic Resonance in 2009. The editors were impressed with the high quality of the submissions, of which our acceptance rate was about 40%. In accordance with open-access publishing, the articles go on-line as they are accepted with no collating of the articles into sections or special thematic issues. We have therefore chosen to briefly summarise the papers in this article for quick reference for our readers in broad areas of interest, which we feel will be useful to practitioners of cardiovascular magnetic resonance (CMR). In some cases where it is considered useful, the articles are also put into the wider context with a short narrative and recent CMR references. It has been a privilege to serve as the Editor of the JCMR this past year. I hope that you find the open-access system increases wider reading and citation of your papers, and that you will continue to send your quality manuscripts to JCMR for publication.
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Affiliation(s)
- DJ Pennell
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP UK. National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ UK
| | - DN Firmin
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP UK. National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ UK
| | - PJ Kilner
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP UK. National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ UK
| | - WJ Manning
- Departments of Medicine (Cardiovascular Division) and Radiology, Beth Israel Deaconess Medical Center 330 Brookline Avenue, Boston, MA 02215 USA. Harvard Medical School, 25 Shattuck Street Boston, MA 02115 USA
| | - RH Mohiaddin
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP UK. National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ UK
| | - S Neubauer
- Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - SK Prasad
- CMR Unit Royal Brompton Hospital, Sydney Street, London SW3 6NP UK. National Heart and Lung Institute, Imperial College, Exhibition Road, London, SW7 2AZ UK
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