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  1. Article ; Online: How to do quantitative myocardial perfusion cardiovascular magnetic resonance.

    Sharrack, Noor / Chiribiri, Amedeo / Schwitter, Juerg / Plein, Sven

    European heart journal. Cardiovascular Imaging

    2021  Volume 23, Issue 3, Page(s) 315–318

    MeSH term(s) Coronary Circulation ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Myocardial Perfusion Imaging ; Perfusion ; Predictive Value of Tests ; Reproducibility of Results
    Language English
    Publishing date 2021-09-29
    Publishing country England
    Document type Journal Article
    ZDB-ID 2638345-7
    ISSN 2047-2412 ; 2047-2404
    ISSN (online) 2047-2412
    ISSN 2047-2404
    DOI 10.1093/ehjci/jeab193
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  2. Article ; Online: Acute Myocarditis Mimicking Hypertrophic Cardiomyopathy in Marfan Syndrome and Morphologically Abnormal Mitral Valve.

    Sharrack, Noor / Poenar, Ana-Maria / Simms, Alexander D / Greenwood, John P / Plein, Sven

    JACC. Case reports

    2022  Volume 4, Issue 2, Page(s) 105–110

    Abstract: A 40-year-old man with Marfan syndrome presented with chest pain and troponin elevation. Urgent echocardiography was suggestive of hypertrophic cardiomyopathy, but cardiovascular magnetic resonance identified features of acute myocarditis. Repeated ... ...

    Abstract A 40-year-old man with Marfan syndrome presented with chest pain and troponin elevation. Urgent echocardiography was suggestive of hypertrophic cardiomyopathy, but cardiovascular magnetic resonance identified features of acute myocarditis. Repeated imaging 4 months later showed resolution of septal thickness, confirming acute myocarditis. (
    Language English
    Publishing date 2022-01-19
    Publishing country Netherlands
    Document type Case Reports
    ISSN 2666-0849
    ISSN (online) 2666-0849
    DOI 10.1016/j.jaccas.2021.11.023
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  3. Article ; Online: The impact of water exchange on estimates of myocardial extracellular volume calculated using contrast enhanced T

    Sharrack, Noor / Biglands, John D / Broadbent, David A / Kellman, Peter / Chow, Kelvin / Greenwood, John P / Levelt, Eylem / Plein, Sven / Buckley, David L

    Magnetic resonance in medicine

    2023  Volume 91, Issue 4, Page(s) 1637–1644

    Abstract: Purpose: Guidelines recommend measuring myocardial extracellular volume (ECV) using T: Methods: Twenty-five patients with severe AS and 5 healthy controls were recruited. T: Results: Median (range) ECV estimated using the 2SXM model was 25% (21%- ... ...

    Abstract Purpose: Guidelines recommend measuring myocardial extracellular volume (ECV) using T
    Methods: Twenty-five patients with severe AS and 5 healthy controls were recruited. T
    Results: Median (range) ECV estimated using the 2SXM model was 25% (21%-39%) for patients and 26% (22%-29%) for controls. ECV estimated in patients using the LM at 10 min following a cumulative contrast dose of 0.15 mmol/kg was 21% (17%-32%) and increased significantly to 22% (19%-35%) at 30 min (p = 0.0001). ECV estimated using the LM was highest following low dose gadobutrol, 25% (19%-38%).
    Conclusion: Current guidelines on contrast agent dose for ECV measurements may lead to underestimated ECV in patients with severe AS because of limited WX. Use of a lower contrast agent dose may mitigate this effect.
    MeSH term(s) Humans ; Contrast Media ; Organometallic Compounds ; Myocardium ; Predictive Value of Tests ; Aortic Valve Stenosis/diagnostic imaging ; Magnetic Resonance Imaging, Cine
    Chemical Substances gadobutrol (1BJ477IO2L) ; Contrast Media ; Organometallic Compounds
    Language English
    Publishing date 2023-12-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 605774-3
    ISSN 1522-2594 ; 0740-3194
    ISSN (online) 1522-2594
    ISSN 0740-3194
    DOI 10.1002/mrm.29956
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  4. Article ; Online: Adrenal haemorrhage as a complication of COVID-19 infection.

    Sharrack, Noor / Baxter, Conal Thomas / Paddock, Michael / Uchegbu, Elizabeth

    BMJ case reports

    2020  Volume 13, Issue 11

    Abstract: We report an unusual complication of COVID-19 infection in a 53-year-old Caucasian man. He presented with shortness of breath, fever and pleuritic chest pain. A CT pulmonary angiogram (CTPA) demonstrated acute bilateral pulmonary embolism and bilateral ... ...

    Abstract We report an unusual complication of COVID-19 infection in a 53-year-old Caucasian man. He presented with shortness of breath, fever and pleuritic chest pain. A CT pulmonary angiogram (CTPA) demonstrated acute bilateral pulmonary embolism and bilateral multifocal parenchymal ground glass change consistent with COVID-19 (SARS-CoV-2) infection. Right adrenal haemorrhage was suspected on the CTPA which was confirmed on triple-phase abdominal CT imaging. A short Synacthen test revealed normal adrenal function. He was treated initially with an intravenous heparin infusion, which was changed to apixaban with a planned outpatient review in 3 months' time. He made an uncomplicated recovery and was discharged. Follow-up imaging nearly 5 months later showed near complete resolution of the right adrenal haemorrhage with no CT evidence of an underlying adrenal lesion.
    MeSH term(s) Adrenal Cortex Function Tests/methods ; Adrenal Gland Diseases/diagnosis ; Adrenal Gland Diseases/etiology ; Adrenal Gland Neoplasms/diagnosis ; Adrenal Glands/diagnostic imaging ; Antithrombins/administration & dosage ; COVID-19/complications ; COVID-19/diagnosis ; COVID-19/physiopathology ; COVID-19/therapy ; Clinical Deterioration ; Computed Tomography Angiography/methods ; Diagnosis, Differential ; Hemorrhage/diagnosis ; Hemorrhage/etiology ; Heparin/administration & dosage ; Humans ; Male ; Middle Aged ; Pulmonary Embolism/diagnosis ; Pulmonary Embolism/etiology ; Pulmonary Embolism/physiopathology ; Pulmonary Embolism/therapy ; Pyrazoles/administration & dosage ; Pyridones/administration & dosage ; SARS-CoV-2/isolation & purification ; SARS-CoV-2/pathogenicity ; Treatment Outcome
    Chemical Substances Antithrombins ; Pyrazoles ; Pyridones ; apixaban (3Z9Y7UWC1J) ; Heparin (9005-49-6)
    Language English
    Publishing date 2020-11-30
    Publishing country England
    Document type Case Reports ; Journal Article
    ISSN 1757-790X
    ISSN (online) 1757-790X
    DOI 10.1136/bcr-2020-239643
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  5. Article: Late-onset ataxia telangiectasia.

    Newrick, Laurence / Sharrack, Noor / Hadjivassiliou, Marios

    Neurology. Clinical practice

    2018  Volume 4, Issue 4, Page(s) 365–367

    Language English
    Publishing date 2018-02-23
    Publishing country United States
    Document type Case Reports
    ZDB-ID 2645818-4
    ISSN 2163-0933 ; 2163-0402
    ISSN (online) 2163-0933
    ISSN 2163-0402
    DOI 10.1212/CPJ.0000000000000008
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  6. Article ; Online: AI-AIF: artificial intelligence-based arterial input function for quantitative stress perfusion cardiac magnetic resonance.

    Scannell, Cian M / Alskaf, Ebraham / Sharrack, Noor / Razavi, Reza / Ourselin, Sebastien / Young, Alistair A / Plein, Sven / Chiribiri, Amedeo

    European heart journal. Digital health

    2022  Volume 4, Issue 1, Page(s) 12–21

    Abstract: Aims: One of the major challenges in the quantification of myocardial blood flow (MBF) from stress perfusion cardiac magnetic resonance (CMR) is the estimation of the arterial input function (AIF). This is due to the non-linear relationship between the ... ...

    Abstract Aims: One of the major challenges in the quantification of myocardial blood flow (MBF) from stress perfusion cardiac magnetic resonance (CMR) is the estimation of the arterial input function (AIF). This is due to the non-linear relationship between the concentration of gadolinium and the MR signal, which leads to signal saturation. In this work, we show that a deep learning model can be trained to predict the unsaturated AIF from standard images, using the reference dual-sequence acquisition AIFs (DS-AIFs) for training.
    Methods and results: A 1D U-Net was trained, to take the saturated AIF from the standard images as input and predict the unsaturated AIF, using the data from 201 patients from centre 1 and a test set comprised of both an independent cohort of consecutive patients from centre 1 and an external cohort of patients from centre 2 (
    Conclusion: Quantification of stress perfusion CMR is feasible with a single-sequence acquisition and a single contrast injection using an AI-based correction of the AIF.
    Language English
    Publishing date 2022-12-07
    Publishing country England
    Document type Journal Article
    ISSN 2634-3916
    ISSN (online) 2634-3916
    DOI 10.1093/ehjdh/ztac074
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  7. Article ; Online: Detection of Intramyocardial Iron in Patients Following ST-Elevation Myocardial Infarction Using Cardiac Diffusion Tensor Imaging.

    Das, Arka / Kelly, Christopher / Teh, Irvin / Sharrack, Noor / Stoeck, Christian T / Kozerke, Sebastian / Schneider, Jürgen E / Plein, Sven / Dall'Armellina, Erica

    Journal of magnetic resonance imaging : JMRI

    2022  Volume 56, Issue 4, Page(s) 1171–1181

    Abstract: Background: Intramyocardial hemorrhage (IMH) following ST-elevation myocardial infarction (STEMI) is associated with poor prognosis. In cardiac magnetic resonance (MR), T2* mapping is the reference standard for detecting IMH while cardiac diffusion ... ...

    Abstract Background: Intramyocardial hemorrhage (IMH) following ST-elevation myocardial infarction (STEMI) is associated with poor prognosis. In cardiac magnetic resonance (MR), T2* mapping is the reference standard for detecting IMH while cardiac diffusion tensor imaging (cDTI) can characterize myocardial architecture via fractional anisotropy (FA) and mean diffusivity (MD) of water molecules. The value of cDTI in the detection of IMH is not currently known.
    Hypothesis: cDTI can detect IMH post-STEMI.
    Study type: Prospective.
    Subjects: A total of 50 patients (20% female) scanned at 1-week (V1) and 3-month (V2) post-STEMI.
    Field strength/sequence: A 3.0 T; inversion-recovery T1-weighted-imaging, multigradient-echo T2* mapping, spin-echo cDTI.
    Assessment: T2* maps were analyzed to detect IMH (defined as areas with T2* < 20 msec within areas of infarction). cDTI images were co-registered to produce averaged diffusion-weighted-images (DWIs), MD, and FA maps; hypointense areas were manually planimetered for IMH quantification.
    Statistics: On averaged DWI, the presence of hypointense signal in areas matching IMH on T2* maps constituted to true-positive detection of iron. Independent samples t-tests were used to compare regional cDTI values. Results were considered statistically significant at P ≤ 0.05.
    Results: At V1, 24 patients had IMH on T2*. On averaged DWI, all 24 patients had hypointense signal in matching areas. IMH size derived using averaged-DWI was nonsignificantly greater than from T2* (2.0 ± 1.0 cm<sup>2</sup> vs 1.89 ± 0.96 cm<sup>2</sup> , P = 0.69). Compared to surrounding infarcted myocardium, MD was significantly reduced (1.29 ± 0.20 × 10<sup>-3</sup>  mm<sup>2</sup> /sec vs 1.75 ± 0.16 × 10<sup>-3</sup>  mm<sup>2</sup> /sec) and FA was significantly increased (0.40 ± 0.07 vs 0.23 ± 0.03) within areas of IMH. By V2, all 24 patients with acute IMH continued to have hypointense signals on averaged-DWI in the affected area. T2* detected IMH in 96% of these patients. Overall, averaged-DWI had 100% sensitivity and 96% specificity for the detection of IMH.
    Data conclusion: This study demonstrates that the parameters MD and FA are susceptible to the paramagnetic properties of iron, enabling cDTI to detect IMH.
    Evidence level: 1 TECHNICAL EFFICACY: Stage 2.
    MeSH term(s) Diffusion Tensor Imaging ; Female ; Hemorrhage/pathology ; Humans ; Iron ; Magnetic Resonance Imaging, Cine/methods ; Male ; Myocardium/pathology ; Prospective Studies ; ST Elevation Myocardial Infarction/diagnostic imaging ; ST Elevation Myocardial Infarction/pathology
    Chemical Substances Iron (E1UOL152H7)
    Language English
    Publishing date 2022-01-12
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1146614-5
    ISSN 1522-2586 ; 1053-1807
    ISSN (online) 1522-2586
    ISSN 1053-1807
    DOI 10.1002/jmri.28063
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  8. Article ; Online: Cardiac q-space trajectory imaging by motion-compensated tensor-valued diffusion encoding in human heart in vivo.

    Teh, Irvin / Shelley, David / Boyle, Jordan H / Zhou, Fenglei / Poenar, Ana-Maria / Sharrack, Noor / Foster, Richard J / Yuldasheva, Nadira Y / Parker, Geoff J M / Dall'Armellina, Erica / Plein, Sven / Schneider, Jürgen E / Szczepankiewicz, Filip

    Magnetic resonance in medicine

    2023  Volume 90, Issue 1, Page(s) 150–165

    Abstract: Purpose: Tensor-valued diffusion encoding can probe more specific features of tissue microstructure than what is available by conventional diffusion weighting. In this work, we investigate the technical feasibility of tensor-valued diffusion encoding at ...

    Abstract Purpose: Tensor-valued diffusion encoding can probe more specific features of tissue microstructure than what is available by conventional diffusion weighting. In this work, we investigate the technical feasibility of tensor-valued diffusion encoding at high b-values with q-space trajectory imaging (QTI) analysis, in the human heart in vivo.
    Methods: Ten healthy volunteers were scanned on a 3T scanner. We designed time-optimal gradient waveforms for tensor-valued diffusion encoding (linear and planar) with second-order motion compensation. Data were analyzed with QTI. Normal values and repeatability were investigated for the mean diffusivity (MD), fractional anisotropy (FA), microscopic FA (μFA), isotropic, anisotropic and total mean kurtosis (MKi, MKa, and MKt), and orientation coherence (C
    Results: QTI data in the left ventricular myocardium were MD = 1.62 ± 0.07 μm
    Conclusion: We demonstrated the first tensor-valued diffusion encoding and QTI analysis in the heart in vivo, along with first measurements of myocardial μFA, MKi, MKa, and C
    MeSH term(s) Humans ; Diffusion Tensor Imaging/methods ; Heart/diagnostic imaging ; Diffusion Magnetic Resonance Imaging ; Myocardium ; Heart Ventricles ; Anisotropy
    Language English
    Publishing date 2023-03-20
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 605774-3
    ISSN 1522-2594 ; 0740-3194
    ISSN (online) 1522-2594
    ISSN 0740-3194
    DOI 10.1002/mrm.29637
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  9. Article ; Online: 4D Flow Cardiac MR in Primary Mitral Regurgitation.

    Gorecka, Miroslawa / Cole, Charlotte / Bissell, Malenka M / Craven, Thomas P / Chew, Pei G / Dobson, Laura E / Brown, Louise A E / Paton, Maria F / Higgins, David M / Thirunavukarasu, Sharmaine / Sharrack, Noor / Javed, Wasim / Kotha, Sindhoora / Giannoudi, Marilena / Procter, Henry / Parent, Martine / Kidambi, Ananth / Swoboda, Peter P / Plein, Sven /
    Levelt, Eylem / Garg, Pankaj / Greenwood, John P

    Journal of magnetic resonance imaging : JMRI

    2024  

    Abstract: Background: Four-dimensional-flow cardiac MR (4DF-MR) offers advantages in primary mitral regurgitation. The relationship between 4DF-MR-derived mitral regurgitant volume (MR-Rvol) and the post-operative left ventricular (LV) reverse remodeling has not ... ...

    Abstract Background: Four-dimensional-flow cardiac MR (4DF-MR) offers advantages in primary mitral regurgitation. The relationship between 4DF-MR-derived mitral regurgitant volume (MR-Rvol) and the post-operative left ventricular (LV) reverse remodeling has not yet been established.
    Purpose: To ascertain if the 4DF-MR-derived MR-Rvol correlates with the LV reverse remodeling in primary mitral regurgitation.
    Study type: Prospective, single-center, two arm, interventional vs. nonintervention observational study.
    Population: Forty-four patients (male N = 30; median age 68 [59-75]) with at least moderate primary mitral regurgitation; either awaiting mitral valve surgery (repair [MVr], replacement [MVR]) or undergoing "watchful waiting" (WW).
    Field strength/sequence: 5 T/Balanced steady-state free precession (bSSFP) sequence/Phase contrast imaging/Multishot echo-planar imaging pulse sequence (five shots).
    Assessment: Patients underwent transthoracic echocardiography (TTE), phase-contrast MR (PMRI), 4DF-MR and 6-minute walk test (6MWT) at baseline, and a follow-up PMRI and 6MWT at 6 months. MR-Rvol was quantified by PMRI, 4DF-MR, and TTE by one observer. The pre-operative MR-Rvol was correlated with the post-operative decrease in the LV end-diastolic volume index (LVEDVi).
    Statistical tests: Included Student t-test/Mann-Whitney test/Fisher's exact test, Bland-Altman plots, linear regression analysis and receiver operating characteristic curves. Statistical significance was defined as P < 0.05.
    Results: While Bland-Altman plots demonstrated similar bias between all the modalities, the limits of agreement were narrower between 4DF-MR and PMRI (bias 15; limits of agreement -36 mL to 65 mL), than between 4DF-MR and TTE (bias -8; limits of agreement -106 mL to 90 mL) and PMRI and TTE (bias -23; limits of agreement -105 mL to 59 mL). Linear regression analysis demonstrated a significant association between the MR-Rvol and the post-operative decrease in the LVEDVi, when the MR-Rvol was quantified by PMRI and 4DF-MR, but not by TTE (P = 0.73). 4DF-MR demonstrated the best diagnostic performance for reduction in the post-operative LVEDVi with the largest area under the curve (4DF-MR 0.83; vs. PMRI 0.78; and TTE 0.51; P = 0.89).
    Data conclusion: This study demonstrates the potential clinical utility of 4DF-MR in the assessment of primary mitral regurgitation.
    Evidence level: 2 TECHNICAL EFFICACY: Stage 5.
    Language English
    Publishing date 2024-02-12
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1146614-5
    ISSN 1522-2586 ; 1053-1807
    ISSN (online) 1522-2586
    ISSN 1053-1807
    DOI 10.1002/jmri.29284
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  10. Article ; Online: Pathophysiology of LV Remodeling Following STEMI: A Longitudinal Diffusion Tensor CMR Study.

    Das, Arka / Kelly, Christopher / Teh, Irvin / Stoeck, Christian T / Kozerke, Sebastian / Sharrack, Noor / Swoboda, Peter P / Greenwood, John P / Schneider, Jürgen E / Plein, Sven / Dall'Armellina, Erica

    JACC. Cardiovascular imaging

    2022  Volume 16, Issue 2, Page(s) 159–171

    Abstract: Background: Adverse LV remodeling post-ST-segment elevation myocardial infarction (STEMI) is associated with a poor prognosis, but the underlying mechanisms are not fully understood. Diffusion tensor (DT)-cardiac magnetic resonance (CMR) allows in vivo ... ...

    Abstract Background: Adverse LV remodeling post-ST-segment elevation myocardial infarction (STEMI) is associated with a poor prognosis, but the underlying mechanisms are not fully understood. Diffusion tensor (DT)-cardiac magnetic resonance (CMR) allows in vivo characterization of myocardial architecture and provides unique mechanistic insight into pathophysiologic changes following myocardial infarction.
    Objectives: This study evaluated the potential associations between DT-CMR performed soon after STEMI and long-term adverse left ventricular (LV) remodeling following STEMI.
    Methods: A total of 100 patients with STEMI underwent CMR at 5 days and 12 months post-reperfusion. The protocol included DT-CMR for assessing fractional anisotropy (FA), secondary eigenvector angle (E2A) and helix angle (HA), cine imaging for assessing LV volumes, and late gadolinium enhancement for calculating infarct and microvascular obstruction size. Adverse remodeling was defined as a 20% increase in LV end-diastolic volume at 12 months.
    Results: A total of 32 patients experienced adverse remodeling at 12 months. Compared with patients without adverse remodeling, they had lower FA (0.23 ± 0.03 vs 0.27 ± 0.04; P < 0.001), lower E2A (37 ± 6° vs 51 ± 7°; P < 0.001), and, on HA maps, a lower proportion of myocytes with right-handed orientation (RHM) (8% ± 5% vs 17% ± 9%; P < 0.001) in their acutely infarcted myocardium. On multivariable logistic regression analysis, infarct FA (odds ratio [OR]: <0.01; P = 0.014) and E2A (OR: 0.77; P = 0.001) were independent predictors of adverse LV remodeling after adjusting for left ventricular ejection fraction (LVEF) and infarct size. There were no significant changes in infarct FA, E2A, or RHM between the 2 scans.
    Conclusions: Extensive cardiomyocyte disorganization (evidenced by low FA), acute loss of sheetlet angularity (evidenced by low E2A), and a greater loss of organization among cardiomyocytes with RHM, corresponding to the subendocardium, can be detected within 5 days post-STEMI. These changes persist post-injury, and low FA and E2A are independently associated with long-term adverse remodeling.
    MeSH term(s) Humans ; ST Elevation Myocardial Infarction/diagnostic imaging ; ST Elevation Myocardial Infarction/therapy ; ST Elevation Myocardial Infarction/pathology ; Stroke Volume ; Magnetic Resonance Imaging, Cine/methods ; Contrast Media ; Ventricular Function, Left ; Predictive Value of Tests ; Gadolinium ; Myocardial Infarction ; Percutaneous Coronary Intervention ; Ventricular Remodeling
    Chemical Substances Contrast Media ; Gadolinium (AU0V1LM3JT)
    Language English
    Publishing date 2022-06-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2491503-8
    ISSN 1876-7591 ; 1936-878X
    ISSN (online) 1876-7591
    ISSN 1936-878X
    DOI 10.1016/j.jcmg.2022.04.002
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