38 results on '"Piechnik, Stefan K."'
Search Results
2. Cardiovascular magnetic resonance reference values of mitral and tricuspid annular dimensions: the UK Biobank cohort
- Author
-
Ricci, Fabrizio, Aung, Nay, Gallina, Sabina, Zemrak, Filip, Fung, Kenneth, Bisaccia, Giandomenico, Paiva, Jose Miguel, Khanji, Mohammed Y., Mantini, Cesare, Palermi, Stefano, Lee, Aaron M., Piechnik, Stefan K., Neubauer, Stefan, and Petersen, Steffen E.
- Published
- 2021
- Full Text
- View/download PDF
3. Right ventricular shape and function: cardiovascular magnetic resonance reference morphology and biventricular risk factor morphometrics in UK Biobank
- Author
-
Mauger, Charlène, Gilbert, Kathleen, Lee, Aaron M., Sanghvi, Mihir M., Aung, Nay, Fung, Kenneth, Carapella, Valentina, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., Suinesiaputra, Avan, and Young, Alistair A.
- Published
- 2019
- Full Text
- View/download PDF
4. Automated quality control in image segmentation: application to the UK Biobank cardiovascular magnetic resonance imaging study
- Author
-
Robinson, Robert, Valindria, Vanya V., Bai, Wenjia, Oktay, Ozan, Kainz, Bernhard, Suzuki, Hideaki, Sanghvi, Mihir M., Aung, Nay, Paiva, José Miguel, Zemrak, Filip, Fung, Kenneth, Lukaschuk, Elena, Lee, Aaron M., Carapella, Valentina, Kim, Young Jin, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., Page, Chris, Matthews, Paul M., Rueckert, Daniel, and Glocker, Ben
- Published
- 2019
- Full Text
- View/download PDF
5. Automated cardiovascular magnetic resonance image analysis with fully convolutional networks
- Author
-
Bai, Wenjia, Sinclair, Matthew, Tarroni, Giacomo, Oktay, Ozan, Rajchl, Martin, Vaillant, Ghislain, Lee, Aaron M., Aung, Nay, Lukaschuk, Elena, Sanghvi, Mihir M., Zemrak, Filip, Fung, Kenneth, Paiva, Jose Miguel, Carapella, Valentina, Kim, Young Jin, Suzuki, Hideaki, Kainz, Bernhard, Matthews, Paul M., Petersen, Steffen E., Piechnik, Stefan K., Neubauer, Stefan, Glocker, Ben, and Rueckert, Daniel
- Published
- 2018
- Full Text
- View/download PDF
6. Splenic T1-mapping: a novel quantitative method for assessing adenosine stress adequacy for cardiovascular magnetic resonance
- Author
-
Liu, Alexander, Wijesurendra, Rohan S., Ariga, Rina, Mahmod, Masliza, Levelt, Eylem, Greiser, Andreas, Petrou, Mario, Krasopoulos, George, Forfar, John C., Kharbanda, Rajesh K., Channon, Keith M., Neubauer, Stefan, Piechnik, Stefan K., and Ferreira, Vanessa M.
- Published
- 2017
- Full Text
- View/download PDF
7. Automated quality control in image segmentation: application to the UK Biobank cardiac MR imaging study
- Author
-
Robinson, Robert, Valindria, Vanya V., Bai, Wenjia, Oktay, Ozan, Kainz, Bernhard, Suzuki, Hideaki, Sanghvi, Mihir M., Aung, Nay, Paiva, Jos$é$ Miguel, Zemrak, Filip, Fung, Kenneth, Lukaschuk, Elena, Lee, Aaron M., Carapella, Valentina, Kim, Young Jin, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., Page, Chris, Matthews, Paul M., Rueckert, Daniel, Glocker, Ben, Engineering & Physical Science Research Council (EPSRC), GlaxoSmithKline, National Institute for Health Research, UK DRI Ltd, Commission of the European Communities, and Innovate UK
- Subjects
FOS: Computer and information sciences ,Population imaging ,Nuclear Medicine & Medical Imaging ,Segmentation ,Computer Vision and Pattern Recognition (cs.CV) ,Computer Science - Computer Vision and Pattern Recognition ,Automatic quality control ,1102 Cardiovascular Medicine And Haematology ,cs.CV - Abstract
Background: The trend towards large-scale studies including population imaging poses new challenges in terms of quality control (QC). This is a particular issue when automatic processing tools, e.g. image segmentation methods, are employed to derive quantitative measures or biomarkers for later analyses. Manual inspection and visual QC of each segmentation isn't feasible at large scale. However, it's important to be able to automatically detect when a segmentation method fails so as to avoid inclusion of wrong measurements into subsequent analyses which could lead to incorrect conclusions. Methods: To overcome this challenge, we explore an approach for predicting segmentation quality based on Reverse Classification Accuracy, which enables us to discriminate between successful and failed segmentations on a per-cases basis. We validate this approach on a new, large-scale manually-annotated set of 4,800 cardiac magnetic resonance scans. We then apply our method to a large cohort of 7,250 cardiac MRI on which we have performed manual QC. Results: We report results used for predicting segmentation quality metrics including Dice Similarity Coefficient (DSC) and surface-distance measures. As initial validation, we present data for 400 scans demonstrating 99% accuracy for classifying low and high quality segmentations using predicted DSC scores. As further validation we show high correlation between real and predicted scores and 95% classification accuracy on 4,800 scans for which manual segmentations were available. We mimic real-world application of the method on 7,250 cardiac MRI where we show good agreement between predicted quality metrics and manual visual QC scores. Conclusions: We show that RCA has the potential for accurate and fully automatic segmentation QC on a per-case basis in the context of large-scale population imaging as in the UK Biobank Imaging Study., Comment: 14 pages, 7 figures, Journal of Cardiovascular Magnetic Resonance
- Published
- 2019
8. Adenosine stress CMR T1-mapping detects early microvascular dysfunction in patients with type 2 diabetes mellitus without obstructive coronary artery disease.
- Author
-
Levelt, Eylem, Piechnik, Stefan K., Liu, Alexander, Wijesurendra, Rohan S., Mahmod, Masliza, Ariga, Rina, Francis, Jane M., Greiser, Andreas, Clarke, Kieran, Neubauer, Stefan, Ferreira, Vanessa M., and Karamitsos, Theodoros D.
- Subjects
- *
ADENOSINES , *TYPE 2 diabetes , *PAPER chromatography , *PEPTIDES , *RESEARCH funding , *DATA analysis software , *DESCRIPTIVE statistics - Abstract
Background: Type 2 diabetes mellitus (T2DM) is associated with coronary microvascular dysfunction in the absence of obstructive coronary artery disease (CAD). Cardiovascular magnetic resonance (CMR) T1-mapping at rest and during adenosine stress can assess coronary vascular reactivity. We hypothesised that the non-contrast T1 response to vasodilator stress will be altered in patients with T2DM without CAD compared to controls due to coronary microvascular dysfunction. Methods: Thirty-one patients with T2DM and sixteen matched healthy controls underwent CMR (3 T) for cine, rest and adenosine stress non-contrast T1-mapping (ShMOLLI), first-pass perfusion and late gadolinium enhancement (LGE) imaging. Significant CAD (>50% coronary luminal stenosis) was excluded in all patients by coronary computed tomographic angiography. Results: All subjects had normal left ventricular (LV) ejection and LV mass index, with no LGE. Myocardial perfusion reserve index (MPRI) was lower in T2DM than in controls (1.60 ± 0.44 vs 2.01 ± 0.42; p = 0.008). There was no difference in rest native T1 values (p = 0.59). During adenosine stress, T1 values increased significantly in both T2DM patients (from 1196 ± 32 ms to 1244 ± 44 ms, p < 0.001) and controls (from 1194 ± 26 ms to 1273 ± 44 ms, p < 0. 001). T2DM patients showed blunted relative stress non-contrast T1 response (T2DM: ΔT1 = 4.1 ± 2.9% vs. controls: ΔT1 = 6.6 ± 2.6%, p = 0.007) due to a blunted maximal T1 during adenosine stress (T2DM 1244 ± 44 ms vs. controls 1273 ± 44 ms, p = 0.045). Conclusions: Patients with well controlled T2DM, even in the absence of arterial hypertension and significant CAD, exhibit blunted maximal non-contrast T1 response during adenosine vasodilatory stress, likely reflecting coronary microvascular dysfunction. Adenosine stress and rest T1 mapping can detect subclinical abnormalities of the coronary microvasculature, without the need for gadolinium contrast agents. CMR may identify early features of the diabetic heart phenotype and subclinical cardiac risk markers in patients with T2DM, providing an opportunity for early therapeutic intervention. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
9. Adenosine stress native T1 mapping in severe aortic stenosis: evidence for a role of the intravascular compartment on myocardial T1 values.
- Author
-
Mahmod, Masliza, Piechnik, Stefan K., Levelt, Eylem, Ferreira, Vanessa M., Francis, Jane M., Lewis, Andrew, Pal, Nikhil, Dass, Sairia, Ashrafian, Houman, Neubauer, Stefan, and Karamitsos, Theodoros D.
- Subjects
- *
LEFT heart ventricle , *HEART physiology , *MYOCARDIUM physiology , *ADENOSINES , *AORTIC stenosis , *VASODILATION , *DIAGNOSTIC imaging , *HEART function tests , *PROSTHETIC heart valves , *HYPEREMIA , *MAGNETIC resonance imaging , *POSTOPERATIVE period , *CONTRAST media , *SEVERITY of illness index , *INTRAVASCULAR space , *PREOPERATIVE period , *DIAGNOSIS - Abstract
Background: Myocardial T1 relaxation times have been reported to be markedly abnormal in diverse myocardial pathologies, ascribed to interstitial changes, evaluated by T1 mapping and calculation of extracellular volume (ECV). T1 mapping is sensitive to myocardial water content of both intra- and extracellular in origin, but the effect of intravascular compartment changes on T1 has been largely neglected. We aimed to assess the role of intravascular compartment on native (pre-contrast) T1 values by studying the effect of adenosine-induced vasodilatation in patients with severe aortic stenosis (AS) before and after aortic valve replacement (AVR). Methods: 42 subjects (26 patients with severe AS without obstructive coronary artery disease and 16 controls) underwent cardiovascular magnetic resonance at 3 T for native T1-mapping (ShMOLLI), first-pass perfusion (myocardial perfusion reserve index-MPRI) at rest and during adenosine stress, and late gadolinium enhancement (LGE). Results: AS patients had increased resting myocardial T1 (1196 ± 47 ms vs. 1168 ± 27 ms, p = 0.037), reduced MPRI (0.92 ± 0.31 vs. 1.74 ± 0.32, p < 0.001), and increased left ventricular mass index (LVMI) and LGE volume compared to controls. During adenosine stress, T1 in AS was similar to controls (1240 ± 51 ms vs. 1238 ± 54 ms, p = 0.88), possibly reflecting a similar level of maximal coronary vasodilatation in both groups. Conversely, the T1 response to stress was blunted in AS (AT1 3.7 ± 2.7% vs. 6.0 ± 4.2% in controls, p = 0.013). Seven months after AVR (n = 16) myocardial T1 and response to adenosine stress recovered towards normal. Native T1 values correlated with reduced MPRI, aortic valve area, and increased LVMI. Conclusions: Our study suggests that native myocardial T1 values are not only influenced by interstitial and intracellular water changes, but also by changes in the intravascular compartment. Performing T1 mapping during or soon after vasodilator stress may affect ECV measurements given that hyperemia alone appears to substantially alter T1 values. [ABSTRACT FROM AUTHOR]
- Published
- 2014
10. Native T1-mapping detects the location, extent and patterns of acute myocarditis without the need for gadolinium contrast agents.
- Author
-
Ferreira, Vanessa M., Piechnik, Stefan K., Dall¿Armellina, Erica, Karamitsos, Theodoros D., Francis, Jane M., Ntusi, Ntobeko, Holloway, Cameron, Choudhury, Robin P., Kardos, Attila, Robson, Matthew D., Friedrich, Matthias G., and Neubauer, Stefan
- Subjects
- *
MAGNETIC resonance imaging , *ANALYSIS of variance , *LONGITUDINAL method , *CARDIOMYOPATHIES , *STATISTICS , *T-test (Statistics) , *U-statistics , *DATA analysis , *CONTRAST media , *RECEIVER operating characteristic curves , *DATA analysis software , *DESCRIPTIVE statistics , *DIAGNOSIS - Abstract
Background Acute myocarditis can be diagnosed on cardiovascular magnetic resonance (CMR) using multiple techniques, including late gadolinium enhancement (LGE) imaging, which requires contrast administration. Native T1-mapping is significantly more sensitive than LGE and conventional T2-weighted (T2W) imaging in detecting myocarditis. The aims of this study were to demonstrate how to display the non-ischemic patterns of injury and to quantify myocardial involvement in acute myocarditis without the need for contrast agents, using topographic T1-maps and incremental T1 thresholds. Methods We studied 60 patients with suspected acute myocarditis (median 3 days from presentation) and 50 controls using CMR (1.5 T), including:(1) dark-blood T2W imaging; (2) native T1-mapping (ShMOLLI); (3) LGE. Analysis included: (1) global myocardial T2 signal intensity (SI) ratio compared to skeletal muscle; (2) myocardial T1 times; (3) areas of injury by T2W, T1-mapping and LGE. Results Compared to controls, patients had more edema (global myocardial T2 SI ratio 1.71 ± 0.27 vs.1.56 ± 0.15), higher mean myocardial T1 (1011 ± 64 ms vs. 946 ± 23 ms) and more areas of injury as detected by T2W (median 5% vs. 0%), T1 (median 32% vs. 0.7%) and LGE (median 11% vs. 0%); all p < 0.001. A threshold of T1 > 990 ms (sensitivity 90%, specificity 88%) detected significantly larger areas of involvement than T2W and LGE imaging in patients, and additional areas of injury when T2W and LGE were negative. T1-mapping significantly improved the diagnostic confidence in an additional 30% of cases when at least one of the conventional methods (T2W, LGE) failed to identify any areas of abnormality. Using incremental thresholds, T1-mapping can display the non-ischemic patterns of injury typical of myocarditis. Conclusion Native T1-mapping can display the typical non-ischemic patterns in acute myocarditis, similar to LGE imaging but without the need for contrast agents. In addition, T1-mapping offers significant incremental diagnostic value, detecting additional areas of myocardial involvement beyond T2W and LGE imaging and identified extra cases when these conventional methods failed to identify abnormalities. In the future, it may be possible to perform gadolinium-free CMR using cine and T1-mapping for tissue characterization and may be particularly useful for patients in whom gadolinium contrast is contraindicated. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
11. Subclinical myocardial inflammation and diffuse fibrosis are common in systemic sclerosis - a clinical study using myocardial T1-mapping and extracellular volume quantification.
- Author
-
Ntusi, Ntobeko A. B., Piechnik, Stefan K., Francis, Jane M., Ferreira, Vanessa M., Rai, Aitzaz B. S., Matthews, Paul M., Robson, Matthew D., Moon, James, Wordsworth, Paul B., Neubauer, Stefan, and Karamitsos, Theodoros D.
- Subjects
- *
INFLAMMATION , *FIBROSIS , *MAGNETIC resonance imaging , *ECHOCARDIOGRAPHY , *CHI-squared test , *STATISTICAL correlation , *FISHER exact test , *LONGITUDINAL method , *MYOCARDIUM , *RESEARCH funding , *STATISTICS , *SYSTEMIC scleroderma , *T-test (Statistics) , *U-statistics , *DATA analysis , *DATA analysis software , *DESCRIPTIVE statistics , *DISEASE complications , *DIAGNOSIS - Abstract
Background Systemic sclerosis (SSc) is characterised by multi-organ tissue fibrosis including the myocardium. Diffuse myocardial fibrosis can be detected non-invasively by T1 and extracellular volume (ECV) quantification, while focal myocardial inflammation and fibrosis may be detected by T2-weighted and late gadolinium enhancement (LGE), respectively, using cardiovascular magnetic resonance (CMR). We hypothesised that multiparametric CMR can detect subclinical myocardial involvement in patients with SSc. Methods 19 SSc patients (18 female, mean age 55 ± 10 years) and 20 controls (19 female, mean age 56 ± 8 years) without overt cardiovascular disease underwent CMR at 1.5T, including cine, tagging, T1-mapping, T2-weighted, LGE imaging and ECV quantification. Results Focal fibrosis on LGE was found in 10 SSc patients (53%) but none of controls. SSc patients also had areas of myocardial oedema on T2-weighted imaging (median 13 vs. 0% in controls). SSc patients had significantly higher native myocardial T1 values (1007 ± 29 vs. 958 ± 20 ms, p < 0.001), larger areas of myocardial involvement by native T1 >990 ms (median 52 vs. 3% in controls) and expansion of ECV (35.4 ± 4.8 vs. 27.6 ± 2.5%, p < 0.001), likely representing a combination of low-grade inflammation and diffuse myocardial fibrosis. Regardless of any regional fibrosis, native T1 and ECV were significantly elevated in SSc and correlated with disease activity and severity. Although biventricular size and global function were preserved, there was impairment in the peak systolic circumferential strain (-16.8 ± 1.6 vs. -18.6 ± 1.0, p < 0.001) and peak diastolic strain rate (83 ± 26 vs. 114 ± 16 s-1, p < 0.001) in SSc, which inversely correlated with diffuse myocardial fibrosis indices. Conclusions Cardiac involvement is common in SSc even in the absence of cardiac symptoms, and includes chronic myocardial inflammation as well as focal and diffuse myocardial fibrosis. Myocardial abnormalities detected on CMR were associated with impaired strain parameters, as well as disease activity and severity in SSc patients. CMR may be useful in future in the study of treatments aimed at preventing or reducing adverse myocardial processes in SSc. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
12. Normal variation of magnetic resonance T1 relaxation times in the human population at 1.5 T using ShMOLLI.
- Author
-
Piechnik, Stefan K., Vanessa M Ferreira, Vanessa M., Lewandowski, Adam J., Ntusi, Ntobeko A. B., Banerjee, Rajarshi, Holloway, Cameron, Hofman, Mark B. M., Sado, Daniel M., Maestrini, Viviana, White, Steven K., Lazdam, Merzaka, Karamitsos, Theodoros, Moon, James C., Neubauer, Stefan, Leeson, Paul, and Robson, Matthew D.
- Abstract
Background: Quantitative T1-mapping is rapidly becoming a clinical tool in cardiovascular magnetic resonance (CMR) to objectively distinguish normal from diseased myocardium. The usefulness of any quantitative technique to identify disease lies in its ability to detect significant differences from an established range of normal values. We aimed to assess the variability of myocardial T1 relaxation times in the normal human population estimated with recently proposed Shortened Modified Look-Locker Inversion recovery (ShMOLLI) T1 mapping technique. Methods: A large cohort of healthy volunteers (n = 342, 50% females, age 11-69 years) from 3 clinical centres across two countries underwent CMR at 1.5T. Each examination provided a single average myocardial ShMOLLI T1 estimate using manually drawn myocardial contours on typically 3 short axis slices (average 3.4 ± 1.4), taking care not to include any blood pool in the myocardial contours. We established the normal reference range of myocardial and blood T1 values, and assessed the effect of potential confounding factors, including artefacts, partial volume, repeated measurements, age, gender, body size, hematocrit and heart rate. Results: Native myocardial ShMOLLI T1 was 962 ± 25 ms. We identify the partial volume as primary source of potential error in the analysis of respective T1 maps and use 1 pixel erosion to represent "midwall myocardial" T1, resulting in a 0.9% decrease to 953 ± 23 ms. Midwall myocardial ShMOLLI T1 was reproducible with an intraindividual, intra- and inter-scanner variability of ≤2%. The principle biological parameter influencing myocardial ShMOLLI T1 was the female gender, with female T1 longer by 24 ms up to the age of 45 years, after which there was no significant difference from males. After correction for age and gender dependencies, heart rate was the only other physiologic factor with a small effect on myocardial ShMOLLI T1 (6ms/10bpm). Left and right ventricular blood ShMOLLI T1 correlated strongly with each other and also with myocardial T1 with the slope of 0.1 that is justifiable by the resting partition of blood volume in myocardial tissue. Overall, the effect of all variables on myocardial ShMOLLI T1 was within 2% of relative changes from the average. Conclusion: Native T1-mapping using ShMOLLI generates reproducible and consistent results in normal individuals within 2% of relative changes from the average, well below the effects of most acute forms of myocardial disease. The main potential confounder is the partial volume effect arising from over-inclusion of neighbouring tissue at the manual stages of image analysis. In the study of cardiac conditions such as diffuse fibrosis or small focal changes, the use of "myocardial midwall" T1, age and gender matching, and compensation for heart rate differences may all help to improve the method sensitivity in detecting subtle changes. As the accuracy of current T1 measurement methods remains to be established, this study does not claim to report an accurate measure of T1, but that ShMOLLI is a stable and reproducible method for T1-mapping. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
13. Non-contrast T1-mapping detects acute myocardial edema with high diagnostic accuracy: a comparison to T2-weighted cardiovascular magnetic resonance.
- Author
-
Ferreira, Vanessa M, Piechnik, Stefan K, Dall'Armellina, Erica, Karamitsos, Theodoros D, Francis, Jane M, Choudhury, Robin P, Friedrich, Matthias G, Robson, Matthew D, and Neubauer, Stefan
- Subjects
- *
EDEMA , *MYOCARDIAL infarction , *TAKOTSUBO cardiomyopathy , *MAGNETIC resonance , *CORONARY disease , *MYOCARDITIS , *TROPONIN , *DIAGNOSIS of edema , *MAGNETIC resonance imaging , *MYOCARDIUM , *CARDIOMYOPATHIES , *PROBABILITY theory , *RECEIVER operating characteristic curves , *SKELETAL muscle , *DESCRIPTIVE statistics - Abstract
Background: T2w-CMR is used widely to assess myocardial edema. Quantitative T1-mapping is also sensitive to changes in free water content. We hypothesized that T1-mapping would have a higher diagnostic performance in detecting acute edema than dark-blood and bright-blood T2w-CMR. Methods: We investigated 21 controls (55 ± 13 years) and 21 patients (61 ± 10 years) with Takotsubo cardiomyopathy or acute regional myocardial edema without infarction. CMR performed within 7 days included cine, T1-mapping using ShMOLLI, dark-blood T2-STIR, bright-blood ACUT2E and LGE imaging. We analyzed wall motion, myocardial T1 values and T2 signal intensity (SI) ratio relative to both skeletal muscle and remote myocardium. Results: All patients had acute cardiac symptoms, increased Troponin I (0.15-36.80 ug/L) and acute wall motion abnormalities but no LGE. T1 was increased in patient segments with abnormal and normal wall motion compared to controls (1113 ± 94 ms, 1029 ± 59 ms and 944 ± 17 ms, respectively; p<0.001). T2 SI ratio using STIR and ACUT2E was also increased in patient segments with abnormal and normal wall motion compared to controls (all p<0.02). Receiver operator characteristics analysis showed that T1-mapping had a significantly larger area-under-the-curve (AUC = 0.94) compared to T2-weighted methods, whether the reference ROI was skeletal muscle or remote myocardium (AUC = 0.58-0.89; p<0.03). A T1 value of greater than 990 ms most optimally differentiated segments affected by edema from normal segments at 1.5 T, with a sensitivity and specificity of 92 %. Conclusions: Non-contrast T1-mapping using ShMOLLI is a novel method for objectively detecting myocardial edema with a high diagnostic performance. T1-mapping may serve as a complementary technique to T2-weighted imaging for assessing myocardial edema in ischemic and non-ischemic heart disease, such as quantifying area-at-risk and diagnosing myocarditis. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
14. Shortened Modified Look-Locker Inversion recovery (ShMOLLI) for clinical myocardial T1- mapping at 1.5 and 3 T within a 9 heartbeatbreathhold.
- Author
-
Piechnik, Stefan K., Ferreira, Vanessa M., Dall'Armellina, Erica, Cochlin, Lowri E., Greiser, Andreas, Neubauer, Stefan, and Robson, Matthew D.
- Subjects
- *
CARDIOVASCULAR diseases , *MYOCARDIUM , *MAGNETIC resonance imaging , *COMPUTER simulation , *CARDIAC patients - Abstract
Background: T1 mapping allows direct in-vivo quantitation of microscopic changes in the myocardium, providing new diagnostic insights into cardiac disease. Existing methods require long breath holds that are demanding for many cardiac patients. In this work we propose and validate a novel, clinically applicable, pulse sequence for myocardial T1-mapping that is compatible with typical limits for end-expiration breath-holding in patients. Materials and methods: The Shortened MOdified Look-Locker Inversion recovery (ShMOLLI) method uses sequential inversion recovery measurements within a single short breath-hold. Full recovery of the longitudinal magnetisation between sequential inversion pulses is not achieved, but conditional interpretation of samples for reconstruction of T1-maps is used to yield accurate measurements, and this algorithm is implemented directly on the scanner. We performed computer simulations for 100 ms
- Published
- 2010
- Full Text
- View/download PDF
15. The diagnostic performance of novel techniques for the detection of acute myocarditis: a clinical study using cardiovascular magnetic resonance imaging.
- Author
-
Ferreira, Vanessa, Piechnik, Stefan K., Dall'Armellina, Erica, Karamitsos, Theodoros, Francis, Jane M., Ntusi, Ntobeko, Holloway, Cameron, Choudhury, Robin P., Kardos, Attila, Robson, Matthew D., Friedrich, Matthias G., and Neubauer, Stefan
- Subjects
- *
CARDIOMYOPATHIES , *CARDIOVASCULAR disease diagnosis , *CONFERENCES & conventions , *MAGNETIC resonance imaging , *DIAGNOSIS - Abstract
An abstract of the article "The diagnostic performance of novel techniques for the detection of acute myocarditis: a clinical study using cardiovascular magnetic resonance imaging," by Vanessa Ferreira and colleagues is presented.
- Published
- 2013
- Full Text
- View/download PDF
16. T1-mapping accurately detects acute myocardial edema: a comparison to T2-weighted cardiovascular magnetic resonance imaging.
- Author
-
Ferreira, Vanessa, Piechnik, Stefan K., Dall'Armellina, Erica, Karamitsos, Theodoros, Francis, Jane M., Choudhury, Robin P., Friedrich, Matthias G., Robson, Matthew D., and Neubauer, Stefan
- Subjects
- *
CARDIOVASCULAR system , *EDEMA , *MAGNETIC resonance imaging - Abstract
An abstract of the conference paper "T1-mapping accurately detects acute myocardial edema: A comparison to T2-weighted cardiovascular magnetic resonance imaging," by Daniel Messroghli and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
17. Single breath-hold Vd(m) calculation as good as multi breath-hold technique in Equilibrium Contrast CMR.
- Author
-
Sado, Daniel, Piechnik, Stefan K., Robson, Matthew D., Maestrini, Viviana, Flett, Andrew, White, Steven K., Banypersad, Sanjay M., and Moon, James
- Subjects
- *
CARDIOVASCULAR system , *MAGNETIC resonance imaging - Abstract
An abstract of the conference paper "Single breath-hold Vd(m) calculation as good as multi breath-hold technique in Equilibrium Contrast CMR," by Daniel Sado and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
18. Age and gender dependence of pre-contrast T1-relaxation times in normal human myocardium at 1.5T using ShMOLLI.
- Author
-
Piechnik, Stefan K., Ferreira, Vanessa, Lewandowski, Adam J., Ntusi, Ntobeko, Sado, Daniel, Maestrini, Viviana, White, Steven K., Lazdam, Merzaka, Banerjee, Rajarshi, Hofman, Mark B., Moon, James, Neubauer, Stefan, Leeson, Paul, and Robson, Matthew D.
- Subjects
- *
MYOCARDIUM - Abstract
An abstract of the conference paper "Age and gender dependence of pre-contrast T1-relaxation times in normal human myocardium at 1.5T using ShMOLLI," by Stefan K. Piechnik and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
19. The diagnostic performance of non-contrast T1-mapping in patients with acute myocarditis on cardiovascular magnetic resonance imaging.
- Author
-
Ferreira, Vanessa, Piechnik, Stefan K., Dall'Armellina, Erica, Karamitsos, Theodoros, Francis, Jane M., Choudhury, Robin P., Kardos, Attila, Friedrich, Matthias G., Robson, Matthew D., and Neubauer, Stefan
- Subjects
- *
MYOCARDITIS - Abstract
An abstract of the article " The diagnostic performance of non-contrast T1-mapping in patients with acute myocarditis on cardiovascular magnetic resonance imaging," by Vanessa Ferreira and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
20. Characterization of acute myocardial infarction by pre-contrast T1 mapping.
- Author
-
Dall'Armellina, Erica, Piechnik, Stefan K., Ferreira, Vanessa, Francis, Jane M., Robson, Matthew D., Cuculi, Florim, Kharbanda, Rajesh, Banning, Adrian P., Choudhury, Robin P., Karamitsos, Theodoros, and Neubauer, Stefan
- Subjects
- *
MYOCARDIAL infarction - Abstract
An abstract of the conference paper "Characterization of acute myocardial infarction by pre-contrast T1 mapping," by Stefan K. Piechnik and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
21. Histological validation of ShMOLLI equilibrium contrast CMR for the measurement of diffuse myocardial fibrosis.
- Author
-
White, Steven K., Piechnik, Stefan K., Neubauer, Stefan, Robson, Matthew D., and Moon, James
- Subjects
- *
CARDIOVASCULAR system , *FIBROSIS , *MAGNETIC resonance imaging - Abstract
An abstract of the conference paper "Histological validation of ShMOLLI equilibrium contrast CMR for the measurement of diffuse myocardial fibrosis," by Steven K. White and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
22. Gaussian modelling for operator-independent and threshold-free volumetric segmentation of phase sensitive inversion recovery late gadolinium enhanced images.
- Author
-
Piechnik, Stefan K., Dall'Armellina, Erica, Ferreira, Vanessa M., and Robson, Matthew D.
- Subjects
- *
GADOLINIUM - Abstract
An abstract of the paper "Gaussian Modelling for Operator-independent and Threshold-free Volumetric Segmentation of Phase Sensitive Inversion Recovery Late Gadolinium Enhanced Images," by Stefan K. Piechnik and colleagues, from the 2011 SCMR/Euro CMR Joint Scientific Sessions, held in Nice, France, from February 3-6, 2011, is presented.
- Published
- 2011
- Full Text
- View/download PDF
23. Quantification of acute myocardial injury by ShMOLLI T1-Mapping, T2-weighted and late gadolinium imaging in patients presenting with chest pain, positive troponins and non-obstructive coronary arteries.
- Author
-
Ferreira, Vanessa M., Piechnik, Stefan K., Dall'Armellina, Erica, Karamitsos, Theodoros D., Francis, Jane M., Friedrich, Matthias G., Robson, Matthew D., and Neubauer, Stefan
- Subjects
- *
CORONARY arteries - Abstract
An abstract of the paper "Quantification of Acute Myocardial Injury by ShMOLLI T1-Mapping, T2-Weighted and Late Gadolinium Imaging in Patients Presenting With Chest Pain, Positive Troponins and Non-Obstructive Coronary Arteries," by Vanessa M. Ferreira and colleagues is presented.
- Published
- 2011
- Full Text
- View/download PDF
24. Quantification of acute myocardial injury in STEMI patients post revascularization at 3Tesla. Comparison of T1-mapping, late gadolinium and edema imaging.
- Author
-
Erica, Dall'Armellina, Piechnik, Stefan K., Ferreira, Vanessa M., Karamitsos, Theodoros D., Francis, Jane M., Robson, Matthew D., Choudhury, Robin P., and Neubauer, Stefan
- Subjects
- *
MYOCARDIUM - Abstract
An abstract of the paper "Quantification of Acute Myocardial Injury in STEMI Patients Post Revascularization at 3Tesla. Comparison of T1-Mapping, Late Gadolinium and Edema Imaging," by Stefan K. Piechnik and colleagues is presented.
- Published
- 2011
- Full Text
- View/download PDF
25. Cardiovascular magnetic resonance reference values of mitral and tricuspid annular dimensions: the UK Biobank cohort.
- Author
-
Ricci, Fabrizio, Aung, Nay, Gallina, Sabina, Zemrak, Filip, Fung, Kenneth, Bisaccia, Giandomenico, Paiva, Jose Miguel, Khanji, Mohammed Y., Mantini, Cesare, Palermi, Stefano, Lee, Aaron M., Piechnik, Stefan K., Neubauer, Stefan, and Petersen, Stefen E.
- Abstract
Background: Mitral valve (MV) and tricuspid valve (TV) apparatus geometry are essential to define mechanisms and etiologies of regurgitation and to inform surgical or transcatheter interventions. Given the increasing use of cardiovascular magnetic resonance (CMR) for the evaluation of valvular heart disease, we aimed to establish CMR-derived age- and sex-specific reference values for mitral annular (MA) and tricuspid annular (TA) dimensions and tethering indices derived from truly healthy Caucasian adults.Methods: 5065 consecutive UK Biobank participants underwent CMR using cine balanced steady-state free precession imaging at 1.5 T. Participants with non-Caucasian ethnicity, prevalent cardiovascular disease and other conditions known to affect cardiac chamber size and function were excluded. Absolute and indexed reference ranges for MA and TA diameters and tethering indices were stratified by gender and age (45–54, 55–64, 65–74 years).Results: Overall, 721 (14.2%) truly healthy participants aged 45–74 years (54% women) formed the reference cohort. Absolute MA and TA diameters, MV tenting length and MV tenting area, were significantly larger in men. Mean ± standard deviation (SD) end-diastolic and end-systolic MA diameters in the 3-chamber view (anteroposterior diameter) were 2.9 ± 0.4 cm (1.5 ± 0.2 cm/m2) and 3.3 ± 0.4 cm (1.7 ± 0.2 cm/m2) in men, and 2.6 ± 0.4 cm (1.6 ± 0.2 cm/m2) and 3.0 ± 0.4 cm (1.8 ± 0.2 cm/m2) in women, respectively. Mean ± SD end-diastolic and end-systolic TA diameters in the 4-chamber view were 3.2 ± 0.5 cm (1.6 ± 0.3 cm/m2) and 3.2 ± 0.5 cm (1.7 ± 0.3 cm/m2) in men, and 2.9 ± 0.4 cm (1.7 ± 0.2 cm/m2) and 2.8 ± 0.4 cm (1.7 ± 0.3 cm/m2) in women, respectively. With advancing age, end-diastolic TA diameter became larger and posterior MV leaflet angle smaller in both sexes. Reproducibility of measurements was good to excellent with an inter-rater intraclass correlation coefficient (ICC) between 0.92 and 0.98 and an intra-rater ICC between 0.90 and 0.97.Conclusions: We described age- and sex-specific reference ranges of MA and TA dimensions and tethering indices in the largest validated healthy Caucasian population. Reference ranges presented in this study may help to improve the distinction between normal and pathological states, prompting the identification of subjects that may benefit from advanced cardiac imaging for annular sizing and planning of valvular interventions. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
26. Measurement of myocardial native T1 in cardiovascular diseases and norm in 1291 subjects.
- Author
-
Liu, Joanna M., Liu, Alexander, Leal, Joana, McMillan, Fiona, Francis, Jane, Greiser, Andreas, Rider, Oliver J., Myerson, Saul, Neubauer, Stefan, Ferreira, Vanessa M., and Piechnik, Stefan K.
- Subjects
- *
CARDIOMYOPATHIES , *CARDIAC hypertrophy , *MYOCARDIUM , *BODY surface mapping , *CARDIOVASCULAR diseases , *REPORTING of diseases , *REFERENCE values , *CONTRAST media , *DATA analysis software , *DESCRIPTIVE statistics , *ANATOMY , *DIAGNOSIS - Abstract
Background: Native T1-mapping provides quantitative myocardial tissue characterization for cardiovascular diseases (CVD), without the need for gadolinium. However, its translation into clinical practice is hindered by differences between techniques and the lack of established reference values. We provide typical myocardial T1-ranges for 18 commonly encountered CVDs using a single T1-mapping technique - Shortened Look-Locker Inversion Recovery (ShMOLLI), also used in the large UK Biobank and Hypertrophic Cardiomyopathy Registry study. Methods: We analyzed 1291 subjects who underwent CMR (1.5-Tesla, MAGNETOM-Avanto, Siemens Healthcare, Erlangen, Germany) between 2009 and 2016, who had a single CVD diagnosis, with mid-ventricular T1-map assessment. A region of interest (ROI) was placed on native T1-maps in the "most-affected myocardium", characterized by the presence of late gadolinium enhancement (LGE), or regional wall motion abnormalities (RWMA) on cines. Another ROI was placed in the "reference myocardium" as far as possible from LGE/RWMA, and in the septum if no focal abnormality was present. To further define normality, we included native T1 of healthy subjects from an existing dataset after sub-endocardial pixelerosions. Results: Native T1 of patients with normal CMR (938 ± 21 ms) was similar compared to healthy subjects (941 ± 23 ms). Across all patient groups (57 ± 19 yrs., 65% males), focally affected myocardium had significantly different T1 value compared to reference myocardium (all p < 0.001). In the affected myocardium, cardiac amyloidosis (1119 ± 61 ms) had the highest native T1 compared to normal and all other CVDs, while iron-overload (795 ± 58 ms) and Anderson-Fabry disease (863 ± 23 ms) had the lowest native reference T1 (all p < 0.001). Future studies designed to detect the large T1 differences between affected and reference myocardium are estimated to require small sample-sizes (n < 50). However, studies designed to detect the small T1 differences between reference myocardium in CVDs and healthy controls can require several thousand of subjects. Conclusions: We provide typical T1-ranges for common clinical cardiac conditions in the largest cohort to-date, using ShMOLLI T1-mapping at 1.5 T. Sample-size calculations from this study may be useful for the design of future studies and trials that use T1-mapping as an endpoint. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
27. Reference ranges for cardiac structure and function using cardiovascular magnetic resonance (CMR) in Caucasians from the UK Biobank population cohort.
- Author
-
Petersen, Steffen E., Nay Aung, Sanghvi, Mihir M., Zemrak, Filip, Fung, Kenneth, Miguel Paiva, Jose, Francis, Jane M., Khanji, Mohammed Y., Lukaschuk, Elena, Lee, Aaron M., Carapella, Valentina, Young Jin Kim, Leeson, Paul, Piechnik, Stefan K., and Neubauer, Stefan
- Subjects
- *
HEART atrium , *HEART ventricles , *AGE distribution , *STATISTICAL correlation , *LEFT heart ventricle , *HEART physiology , *RIGHT heart ventricle , *MAGNETIC resonance imaging , *REFERENCE values , *RESEARCH funding , *SEX distribution , *T-test (Statistics) , *WHITE people , *DATA analysis software , *STROKE volume (Cardiac output) , *INTRACLASS correlation , *PHYSIOLOGY , *ANATOMY - Abstract
Background: Cardiovascular magnetic resonance (CMR) is the gold standard method for the assessment of cardiac structure and function. Reference ranges permit differentiation between normal and pathological states. To date, this study is the largest to provide CMR specific reference ranges for left ventricular, right ventricular, left atrial and right atrial structure and function derived from truly healthy Caucasian adults aged 45-74. Methods: Five thousand sixty-five UK Biobank participants underwent CMR using steady-state free precession imaging at 1.5 Tesla. Manual analysis was performed for all four cardiac chambers. Participants with non-Caucasian ethnicity, known cardiovascular disease and other conditions known to affect cardiac chamber size and function were excluded. Remaining participants formed the healthy reference cohort; reference ranges were calculated and were stratified by gender and age (45-54, 55-64, 65-74). Results: After applying exclusion criteria, 804 (16.²%) participants were available for analysis. Left ventricular (LV) volumes were larger in males compared to females for absolute and indexed values. With advancing age, LV volumes were mostly smaller in both sexes. LV ejection fraction was significantly greater in females compared to males (mean ± standard deviation [SD] of 61 ± 5% vs 58 ± 5%) and remained static with age for both genders. In older age groups, LV mass was lower in men, but remained virtually unchanged in women. LV mass was significantly higher in males compared to females (mean ± SD of 53 ± 9 g/m² vs 4² ± 7 g/m²). Right ventricular (RV) volumes were significantly larger in males compared to females for absolute and indexed values and were smaller with advancing age. RV ejection fraction was higher with increasing age in females only. Left atrial (LA) maximal volume and stroke volume were significantly larger in males compared to females for absolute values but not for indexed values. LA ejection fraction was similar for both sexes. Right atrial (RA) maximal volume was significantly larger in males for both absolute and indexed values, while RA ejection fraction was significantly higher in females. Conclusions: We describe age- and sex-specific reference ranges for the left ventricle, right ventricle and atria in the largest validated normal Caucasian population. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
28. Native T1 lowering in iron overload and Anderson Fabry disease; a novel and early marker of disease.
- Author
-
Sado, Daniel, White, Steven K., Piechnik, Stefan K., Banypersad, Sanjay M., Treibel, Thomas A., Fontana, Marianna, Captur, Gaby, Maestrini, Viviana, Lachmann, Robin, Hughes, Derralyn, Murphy, Elaine, Porter, John, Mehta, Atul, Elliott, Perry, and Moon, James
- Subjects
- *
ANGIOKERATOMA corporis diffusum , *BIOMARKERS , *CONFERENCES & conventions , *IRON in the body , *MAGNETIC resonance imaging , *TIME , *DIAGNOSIS - Abstract
An abstract of the article "Native T1 lowering in iron overload and Anderson Fabry disease; a novel and early marker of disease," by Daniel Sado and colleagues is presented.
- Published
- 2013
- Full Text
- View/download PDF
29. Non-contrast T1 mapping characterizes the myocardium beyond that achieved by late gadolinium enhancement in both hypertrophic and dilated cardiomyopathy.
- Author
-
Dass, Sairia, Suttie, Joseph, Piechnik, Stefan K., Ferreira, Vanessa, Holloway, Cameron, Robson, Matthew D., Watkins, Hugh, Karamitsos, Theodoros, and Neubauer, Stefan
- Subjects
- *
CARDIOMYOPATHIES - Abstract
An abstract of the conference paper "Non-contrast T1 mapping characterizes the myocardium beyond that achieved by late gadolinium enhancement in both hypertrophic and dilated cardiomyopathy," by Sairia Dass and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
30. Systolic ShMOLLI myocardial T1-mapping for improved robustness to partial-volume effects and applications in tachyarrhythmias.
- Author
-
Ferreira, Vanessa M., Wijesurendra, Rohan S., Liu, Alexander, Greiser, Andreas, Casadei, Barbara, Robson, Matthew D., Neubauer, Stefan, and Piechnik, Stefan K.
- Subjects
- *
RESEARCH funding , *SEX distribution , *SINOATRIAL node , *TACHYCARDIA , *DATA analysis software , *DESCRIPTIVE statistics , *KRUSKAL-Wallis Test - Abstract
Background: T1-mapping using the Shortened Modified Look-Locker Inversion Recovery (ShMOLLI) technique enables non-invasive assessment of important myocardial tissue characteristics. However, tachyarrhythmia may cause mistriggering and inaccurate T1 estimation. We set out to test whether systolic T1-mapping might overcome this, and whether T1 values or data quality would be significantly different compared to conventional diastolic T1-mapping. Methods: Native T1 maps were acquired using ShMOLLI at 1.5 T (Magnetom Avanto, Siemens Healthcare) in 10 healthy volunteers (5 male) in sinus rhythm, at varying prescribed trigger delay (TD) times: 0, 50, 100 and 150 ms (all "systolic"), 340 ms (MOLLI TD 500 ms, the conventional TD for ShMOLLI) and also "end diastolic". T1 maps were also acquired using a shorter readout, to explore the effect of reducing image readout time and sensitivity to systolic motion. The feasibility and image quality of systolic T1-mapping was tested in 15 patients with tachyarrhythmia ( = 13 atrial fibrillation, = 2 sinus tachycardia; mean HR range 93-121 bpm). n n Results: In healthy volunteers, systolic readout increased the thickness of myocardium compared to the diastolic readout. There was a small overall effect of TD on T1 values ( = 0.04), with slightly shorter T1 values in systole p compared to diastole (maximum difference 10 ms). While there were apparent gender differences (with no effect of TD on T1 values in males, more marked differences in females, and exaggeration of this effect in thinner myocardial segments in females), dilatation and erosion of contours suggested that the effect of TD on T1 in females was almost entirely due to more partial-volume effects in diastole. All T1 maps were of excellent quality, but systolic TD and shorter readout were associated with less variability in segmental T1 values. In tachycardic patients, systolic acquisitions produced consistently excellent T1 maps (median R² = 0.993). Conclusions: In healthy volunteers, systolic ShMOLLI T1-mapping reduces T1 variability and reports clinically equivalent T1 values to conventional diastolic readout; slightly shorter T1 values in systole are mostly explained by reduced partial-volume effects due to the increase in functional myocardial thickness. In patients with tachyarrhythmia, systolic ShMOLLI T1-mapping is feasible, circumvents mistriggering and produces excellent quality T1 maps. This extends its clinical applicability to challenging rhythms (such as rapid atrial fibrillation) and aids the investigation of thinner myocardial segments. With further validation, systolic T1-mapping may become a new and convenient standard for myocardial T1-mapping. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
31. Reproducibility of native myocardial T1 mapping in the assessment of Fabry disease and its role in early detection of cardiac involvement by cardiovascular magnetic resonance.
- Author
-
Pica, Silvia, Sado, Daniel M., Maestrini, Viviana, Fontana, Marianna, White, Steven K., Treibel, Thomas, Captur, Gabriella, Anderson, Sarah, Piechnik, Stefan K., Robson, Matthew D., Lachmann, Robin H., Murphy, Elaine, Mehta, Atul, Hughes, Derralyn, Kellman, Peter, Elliott, Perry M., Herrey, Anna S., and Moon, James C.
- Subjects
- *
ANGIOKERATOMA corporis diffusum , *LEFT ventricular hypertrophy , *AGE distribution , *AGE factors in disease , *DIASTOLE (Cardiac cycle) , *ECHOCARDIOGRAPHY , *ELECTROCARDIOGRAPHY , *CARDIAC contraction , *MAGNETIC resonance imaging , *SEX distribution , *INTER-observer reliability , *EARLY diagnosis , *GENOTYPES , *INTRACLASS correlation , *GENETICS , *DIAGNOSIS ,RESEARCH evaluation - Abstract
Background: Cardiovascular magnetic resonance (CMR) derived native myocardial T1 is decreased in patients with Fabry disease even before left ventricular hypertrophy (LVH) occurs and may be the first non-invasive measure of myocyte sphingolipid storage. The relationship of native T1 lowering prior to hypertrophy and other candidate early phenotype markers are unknown. Furthermore, the reproducibility of T1 mapping has never been assessed in Fabry disease. Methods: Sixty-three patients, 34 (54%) female, mean age 48 ± 15 years with confirmed (genotyped) Fabry disease underwent CMR, ECG and echocardiographic assessment. LVH was absent in 25 (40%) patients. Native T1 mapping was performed with both Modified Look-Locker Inversion recovery (MOLLI) sequences and a shortened version (ShMOLLI) at 1.5 Tesla. Twenty-one patients underwent a second scan within 24 hours to assess inter-study reproducibility. Results were compared with 63 healthy age and gender-matched volunteers. Results: Mean native T1 in Fabry disease (LVH positive), (LVH negative) and healthy volunteers was 853 ± 50 ms, 904 ± 46 ms and 968 ± 32 ms (for all p < 0.0001) by ShMOLLI sequences. Native T1 showed high inter-study, intra-observer and inter-observer agreement with intra-class correlation coefficients (ICC) of 0.99, 0.98, 0.97 (ShMOLLI) and 0.98, 0.98, 0.98 (MOLLI). In Fabry disease LVH negative individuals, low native T1 was associated with reduced echocardiographic-based global longitudinal speckle tracking strain (-18 ± 2% vs -22 ± 2%, p = 0.001) and early diastolic function impairment (E/E' = 7 [6-8] vs 5 [5-6], p = 0.028). Conclusion: Native T1 mapping in Fabry disease is a reproducible technique. T1 reduction prior to the onset of LVH is associated with early diastolic and systolic changes measured by echocardiography. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
32. Myocardial T1 mapping and extracellular volume quantification: a Society for Cardiovascular Magnetic Resonance (SCMR) and CMR Working Group of the European Society of Cardiology consensus statement.
- Author
-
Moon, James C., Messroghli, Daniel R., Kellman, Peter, Piechnik, Stefan K., Robson, Matthew D., Ugander, Martin, Gatehouse, Peter D., Arai, Andrew E., Friedrich, Matthias G., Neubauer, Stefan, Schulz-Menger, Jeanette, and Schelbert, Erik B.
- Abstract
Rapid innovations in cardiovascular magnetic resonance (CMR) now permit the routine acquisition of quantitative measures of myocardial and blood T1 which are key tissue characteristics. These capabilities introduce a new frontier in cardiology, enabling the practitioner/investigator to quantify biologically important myocardial properties that otherwise can be difficult to ascertain clinically. CMR may be able to track biologically important changes in the myocardium by: a) native T1 that reflects myocardial disease involving the myocyte and interstitium without use of gadolinium based contrast agents (GBCA), or b) the extracellular volume fraction (ECV)-a direct GBCA-based measurement of the size of the extracellular space, reflecting interstitial disease. The latter technique attempts to dichotomize the myocardium into its cellular and interstitial components with estimates expressed as volume fractions. This document provides recommendations for clinical and research T1 and ECV measurement, based on published evidence when available and expert consensus when not. We address site preparation, scan type, scan planning and acquisition, quality control, visualisation and analysis, technical development. We also address controversies in the field. While ECV and native T1 mapping appear destined to affect clinical decision making, they lack multi-centre application and face significant challenges, which demand a community-wide approach among stakeholders. At present, ECV and native T1 mapping appear sufficiently robust for many diseases; yet more research is required before a large-scale application for clinical decision-making can be recommended. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
33. Comparison of T1 mapping techniques for ECV quantification. Histological validation and reproducibility of ShMOLLI versus multibreath-hold T1 quantification equilibrium contrast CMR.
- Author
-
Fontana, Marianna, White, Steve K., Banypersad, Sanjay M., Sado, Daniel M., Maestrini, Viviana, Flett, Andrew S., Piechnik, Stefan K., Neubauer, Stefan, Roberts, Neil, and Moon, James C.
- Subjects
- *
CARDIOMYOPATHIES , *HEART diseases , *AORTIC stenosis , *AORTIC valve diseases , *STENOSIS , *FIBROSIS , *BIOPSY , *COLLAGEN , *CONFIDENCE intervals , *EXTRACELLULAR space , *CARDIAC hypertrophy , *HEMATOCRIT , *MAGNETIC resonance imaging , *MYOCARDIUM , *PROBABILITY theory , *STATISTICAL reliability , *BREATH holding , *PRE-tests & post-tests , *CONTRAST media , *DESCRIPTIVE statistics , *INTRACLASS correlation , *DIAGNOSIS ,RESEARCH evaluation - Abstract
Background: Myocardial extracellular volume (ECV) is elevated in fibrosis or infiltration and can be quantified by measuring the haematocrit with pre and post contrast T1 at sufficient contrast equilibrium. Equilibrium CMR (EQ-CMR), using a bolus-infusion protocol, has been shown to provide robust measurements of ECV using a multibreath-hold T1 pulse sequence. Newer, faster sequences for T1 mapping promise whole heart coverage and improved clinical utility, but have not been validated.Methods: Multibreathhold T1 quantification with heart rate correction and single breath-hold T1 mapping using Shortened Modified Look-Locker Inversion recovery (ShMOLLI) were used in equilibrium contrast CMR to generate ECV values and compared in 3 ways. Firstly, both techniques were compared in a spectrum of disease with variable ECV expansion (n=100, 50 healthy volunteers, 12 patients with hypertrophic cardiomyopathy, 18 with severe aortic stenosis, 20 with amyloid). Secondly, both techniques were correlated to human histological collagen volume fraction (CVF%, n=18, severe aortic stenosis biopsies). Thirdly, an assessment of test:retest reproducibility of the 2 CMR techniques was performed 1 week apart in individuals with widely different ECVs (n=10 healthy volunteers, n=7 amyloid patients). Results: More patients were able to perform ShMOLLI than the multibreath-hold technique (6% unable to breath-hold). ECV calculated by multibreath-hold T1 and ShMOLLI showed strong correlation (r2=0.892), little bias (bias -2.2%, 95%CI -8.9% to 4.6%) and good agreement (ICC 0.922, range 0.802 to 0.961, p<0.0001). ECV correlated with histological CVF% by multibreath-hold ECV (r2= 0.589) but better by ShMOLLI ECV (r2= 0.685). Inter-study reproducibility demonstrated that ShMOLLI ECV trended towards greater reproducibility than the multibreath-hold ECV, although this did not reach statistical significance (95%CI -4.9% to 5.4% versus 95%CI -6.4% to 7.3% respectively, p=0.21). Conclusions: ECV quantification by single breath-hold ShMOLLI T1 mapping can measure ECV by EQ-CMR across the spectrum of interstitial expansion. It is procedurally better tolerated, slightly more reproducible and better correlates with histology compared to the older multibreath-hold FLASH techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
34. Global extracellular volume (ECVglobal) in HCM - the "next generation" test for risk in hypertrophic cardiomyopathy?
- Author
-
Sado, Daniel, Maestrini, Viviana, White, Steven K, Piechnik, Stefan K, Robson, Matthew D, Flett, Andrew, Tome Esteban, Maria T., Pantazis, Antonios, McKenna, William J, Neubauer, Stefan, Elliott, Perry, and Moon, James
- Subjects
- *
CARDIAC hypertrophy , *CONFERENCES & conventions , *EXTRACELLULAR fluid , *DISEASE risk factors - Abstract
An abstract of the article "Global extracellular volume (ECVglobal) in HCM - the next generation test for risk in hypertrophic cardiomyopathy?," by Daniel Sado and colleagues is presented.
- Published
- 2013
- Full Text
- View/download PDF
35. Impaired myocardial perfusion in moderate asymptomatic aortic stenosis relates to longitudinal strain but not non-contrast T1 values.
- Author
-
Bull, Sacha, Loudon, Margaret, Ntusi, Ntobeko, Joseph, Jubin P., Francis, Jane M., Ferreira, Vanessa, Piechnik, Stefan K., Karamitsos, Theodoros, Neubauer, Stefan, and Myerson, Saul
- Subjects
- *
AORTIC stenosis , *BLOOD circulation , *CONFERENCES & conventions , *MAGNETIC resonance imaging , *MYOCARDIUM , *DIAGNOSIS - Abstract
An abstract of the article "Impaired myocardial perfusion in moderate asymptomatic aortic stenosis relates to longitudinal strain but not non-contrast T1 values," by Sacha Bull and colleagues is presented.
- Published
- 2013
- Full Text
- View/download PDF
36. T1 mapping for myocardial extracellular volume measurement by cardiovascular magnetic resonance: bolus only vs primed infusion technique.
- Author
-
White, Steven K., Sado, Daniel, Fontana, Marianna, Banypersad, Sanjay M., Maestrini, Viviana, Piechnik, Stefan K., Robson, Matthew D., Hausenloy, Derek J., Sheikh, Amir M., Hawkins, Philip N., and Moon, James
- Subjects
- *
MYOCARDIUM physiology , *EXTRACELLULAR space , *CARDIOVASCULAR disease diagnosis , *CONFERENCES & conventions , *MAGNETIC resonance imaging , *PHYSIOLOGY - Abstract
An abstract of the article "T1 mapping for myocardial extracellular volume measurement by cardiovascular magnetic resonance: bolus only vs primed infusion technique," by Steven K. White and colleagues is presented.
- Published
- 2013
- Full Text
- View/download PDF
37. Pre-contrast ShMOLLI T1 mapping in cardiac AL amyloidosis.
- Author
-
Karamitsos, Theodoros, Banypersad, Sanjay M., Sado, Daniel, Maestrini, Viviana, Ferreira, Vanessa, Piechnik, Stefan K., Robson, Matthew D., Hawkins, Philip N., Neubauer, Stefan, and Moon, James
- Subjects
- *
AMYLOIDOSIS , *HEART diseases - Abstract
An abstract of the conference paper "Pre-contrast ShMOLLI T1 mapping in cardiac AL amyloidosis," by Theodoros Karamitsos and colleagues is presented.
- Published
- 2012
- Full Text
- View/download PDF
38. Comprehensive cardiac magnetic resonance imaging and spectroscopy reveals a high burden of myocardial disease in HIV infection.
- Author
-
Holloway, Cameron, Ntusi, Ntobeko, Suttie, Joseph, Mahmod, Masliza, Wainwright, Emma, Clutton, Genevieve, Hancock, Gemma, Beak, Philip, Tajar, Abdelouahid, Piechnik, Stefan K., Schneider, Jurgen E., Clarke, Kieran, Dorrell, Lucy, and Neubauer, Stefan
- Subjects
- *
CARDIOMYOPATHIES , *CONFERENCES & conventions , *HIV-positive persons , *MAGNETIC resonance imaging , *SPECTRUM analysis , *DIAGNOSIS - Abstract
An abstract of the article "Comprehensive cardiac magnetic resonance imaging and spectroscopy reveals a high burden of myocardial disease in HIV infection," by Cameron Holloway and colleagues is presented.
- Published
- 2013
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.