Cardiovascular Magnetic Resonance Unit

London, United Kingdom

Cardiovascular Magnetic Resonance Unit

London, United Kingdom
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Ripley D.P.,Cardiovascular Magnetic Resonance Unit | Ripley D.P.,Royal Devon and Exeter Hospital | Gosling O.E.,Cardiovascular Magnetic Resonance Unit | Gosling O.E.,Royal Devon and Exeter Hospital | And 6 more authors.
International Journal of Cardiology | Year: 2014

Background: A collateral circulation which supplies a myocardial territory, subtended by a chronic total occlusion (CTO), may be observed at invasive coronary angiography. The prognostic and protective role of such collateralisation is well demonstrated suggesting that a good collateral circulation may be a predictor of myocardial viability, but current evidence is discrepant. The aim of this study is to assess the relationship between collateralisation from the contralateral epicardial vessels and myocardial viability by cardiovascular magnetic resonance (CMR).Method: Consecutive patients with CTO having had both CMR and invasive coronary angiography were retrospectively identified. The collateral circulation was graded with the Cohen and Rentrop classification. CMR images were graded per segment for wall motion (1: normal/hyperkinetic, 2: hypokinetic, 3: akinetic, or 4: dyskinetic) and wall motion score index (WMSI) was calculated. The segmental transmurality of late gadolinium enhancement was scored as 1 (0%), 2 (1-25%), 3 (26-50%), 4 (51-75%) and 5 (76-100%).Results: A good collateral circulation was more likely to supply viable myocardium (p = 0.01). There was no relationship between collateral circulation supply and wall motion score index (WMSI), however, increasing transmurality of LGE was significantly associated with higher mean WMSI representing increasing dysfunctional myocardium (p < 0.001).Conclusion: The presence of collateral coronary circulation at angiography predicts the presence of viability on cardiovascular MRI, with a gradation of greater viability associated with improving Rentrop grade. A collateral circulation at angiography should, therefore, prompt more formal assessment of viability and consideration of revascularisation in order for the patient to obtain the associated functional and prognostic improvement. © 2014 Elsevier Ireland Ltd. All rights reserved.

Raj V.,University of Leicester | Raj V.,Cardiovascular Magnetic Resonance Unit | Alpendurada F.,Cardiovascular Magnetic Resonance Unit | Christmas T.,Royal Marsden Hospital | And 3 more authors.
Journal of Thoracic and Cardiovascular Surgery | Year: 2012

Objectives: About 1 in 5 patients with renal cell carcinoma have intravascular tumoral extension at presentation. Level of tumoral extension within inferior vena cava determines surgical approach, with higher extension requiring cardiopulmonary bypass. Tumoral invasion of inferior vena caval wall is associated with poor prognosis. We evaluated accuracy of magnetic resonance imaging (MRI) in assessing level of intravascular extension of renal cell carcinoma and predicting vessel wall invasion. Methods: MRIs and surgical database were reviewed from January 1999 to December 2008. Sixty-four patients with suspected intravascular extension of renal cell carcinoma underwent MRI. Forty-one underwent curative or palliative surgery at our institution and were included in final analysis. MRI scans were reviewed to determine intravascular extension and tumoral adherence to the vessel wall, as assessed by circumferential flow around the intravascular tumor and its mobility during different phases of cardiac cycle. MRI findings were correlated with surgical findings to assess accuracy. Results: There was 87.8% agreement (P < .001; κ = 0.82) between MRI and surgical findings regarding level of intravascular extension of tumor. MRI was highly sensitive and specific (93%) in assessing supradiaphragmatic extension (negative predictive value, 96%). Depending on sign used, sensitivities and negative predictive values in assessing tumoral adherence to vessel wall ranged from 86% to 95% and 81% to 91%, respectively. Conclusions: MRI is highly accurate in staging intravascular and intracardiac extension, aiding in accurate preoperative surgical planning. MRI may help determine prognosis of renal cell carcinoma by accurately assessing tumoral adherence to the vessel wall.

Keegan J.,Cardiovascular Biomedical Research Unit | Gatehouse P.D.,Cardiovascular Biomedical Research Unit | Haldar S.,Royal Brompton and Harefield NHS Trust | Wage R.,Cardiovascular Magnetic Resonance Unit | And 4 more authors.
Magnetic Resonance in Medicine | Year: 2015

Purpose: High resolution three-dimensional (3D) late gadolinium enhancement (LGE) imaging is performed with single R-wave gating to minimize lengthy acquisition durations. In patients with atrial fibrillation (AF), heart rate variability results in variable magnetization recovery between sequence repeats, and image quality is often poor. In this study, we implemented and tested a dynamic inversion time (dynamic-TI) scheme designed to reduce sequence sensitivity to heart rate variations. Methods: An inversion-prepared 3D segmented gradient echo sequence was modified so that the TI varied automatically from beat-to-beat (dynamic-TI) based on the time since the last sequence repeat. 3D LGE acquisitions were performed in 17 patients prior to radio frequency ablation of persistent AF both with and without dynamic-TI. Qualitative image quality scores, blood signal-to-ghosting ratios (SGRs). and blood-myocardium contrast-to-ghosting ratios (CGRs) were compared. Results: Image quality scores were higher with dynamic-TI than without dynamic-TI (2.2 ± 0.9 vs. 1.8 ± 1.1, P = 0.008), as were blood-myocardium CGRs (13.8 ± 7.6 vs. 8.3 ± 6.1, P = 0.003) and blood SGRs (19.6 ± 8.5 vs. 13.1 ± 8.0, P = 0.003). Conclusion: The dynamic-TI algorithm improves image quality of 3D LGE imaging in this difficult patient population by reducing the sequence sensitivity to RR interval variations. © 2014 Wiley Periodicals, Inc.

Grasso A.E.,Cardiovascular Magnetic Resonance Unit | Pennell D.J.,Cardiovascular Magnetic Resonance Unit
International Journal of Cardiology | Year: 2010

We present a case of lateral wall infarction in the territory of an anomalous circumflex artery without significant stenosis. The unusual location of the infarction suggests a causal relation with the anomalous artery through minor plaque rupture, which may have resulted from mechanical stress. © 2008 Elsevier Ireland Ltd. All rights reserved.

Fraquelli M.,University of Milan | Cassinerio E.,University of Milan | Roghi A.,Cardiovascular Magnetic Resonance Unit | Rigamonti C.,University of Milan | And 5 more authors.
American Journal of Hematology | Year: 2010

Transient elastography (TE) is a valuable noninvasive technique of measuring liver stiffness and a reliable tool for predicting hepatic fibrosis in patients with chronic liver disease. The role of TE in patients with β-thalassemia has not been extensively investigated. The present study aimed to evaluate the role of TE in the assessment of hepatic fibrosis in 115 adult patients with β-thalassemia major (TM) (#59) or intermedia (TI) (#56). TE was performed according to current practice. Histologic data were obtained in 14 cases. Liver iron concentration was assessed by atomic absorption spectrometry and T2* magnetic resonance. In patients with TM, the proportion of anti-HCV positive viremic patients, median serum ferritin levels, and TE values were significantly higher than in TI. In the group of 14 patients who underwent liver biopsy, a significant positive correlation was observed between liver stiffness and fibrosis stage (r = 0.73, P = 0.003). Severe fibrosis is diagnosed with a sensitivity of 60% and a specificity of 89%, whereas cirrhosis is detected with a sensitivity of 100% and a specificity of 92%. At multivariate analysis, the variables independently associated with TE were ALT, GGT, and bilirubin levels in both groups and, in patients with TM, HCV RNA positivity. In β-thalassemia patients, TE is a reliable tool for assessing liver fibrosis even if the influence of iron overload has to be clarified. © 2010 Wiley-Liss, Inc.

Eleftheriou K.I.,University College London | Rawal J.S.,University College London | Rawal J.S.,Golden Jubilee National Hospital | James L.E.,University College London | And 10 more authors.
Bone | Year: 2013

Background: The development of osteoporosis is influenced by peak bone mass attained in youth - the influence of lifestyle factors upon which is poorly described, especially amongst males. We sought to address this issue in a large scale study. Methods: Hip bone mineral density (dual X-ray absorptiometry, DXA), bone microarchitecture (calcaneal quantitative ultrasound, QUS) and femoral geometry (magnetic resonance imaging, MRI) were characterised in 723 healthy male military recruits (mean ± S.E. age 19.92 ± 0.09. years [range 16-18. years], height 177.67 ± 0.24. cm, weight 73.17 ± 0.37. kg) on entry to UK Army training. Association was sought with prior physical activity, smoking status and alcohol intake. Results: DXA measures were made in 651, MRI measures in 650, and QUS measures in 572 recruits. Increasing levels of weight-bearing physical activity enhanced periostial bone apposition, increases in both total hip and femoral neck bone mineral density (BMD; p≤ 0.0001 in both cases), and cortical [. p< 0.0001] and periostial bone volumes [. p= 0.016]. Smoking habit was associated with preserved bone geometry, but worse BMD [. p= 0.0001] and QUS characteristics [. p≤ 0.0005]. Moderate alcohol consumption was associated with greater BMD [. p≤ 0.015]. Conclusions: Whilst exercise (and perhaps moderate alcohol intake) is beneficial to bone morphometry, smoking is detrimental to bone mineral density in young males notable for the likely short duration of smoking to influence skeletal properties. However, differences in socio-economic status, lifestyle and related environmental factors may to some extent confound our results. © 2012 Elsevier Inc.

Scott A.D.,Imperial College London | Scott A.D.,Cardiovascular Magnetic Resonance Unit | Keegan J.,Imperial College London | Keegan J.,Cardiovascular Magnetic Resonance Unit | And 4 more authors.
Journal of Magnetic Resonance Imaging | Year: 2011

Purpose: To demonstrate coronary artery wall thickening with age in a small healthy cohort using a highly efficient, reliable, and reproducible high-resolution MR technique. Materials and Methods: A 3D cross-sectional MR vessel wall images (0.7 × 0.7 × 3 mm resolution) with retrospective beat-to-beat respiratory motion correction (B2B-RMC) were obtained in the proximal right coronary artery of 21 healthy subjects (age, 22-62 years) with no known cardiovascular disease. Lumen and outer wall (lumen + vessel wall) areas were measured in one central slice from each subject and average wall thickness and wall area/outer wall area ratio (W/OW) calculated. Results: Imaging was successful in 18 (86%) subjects with average respiratory efficiency 99.3 ± 1.7%. Coronary vessel wall thickness and W/OW significantly correlate with subject age, increasing by 0.088 mm and 0.031 per decade respectively (R = 0.53, P = 0.024 and R = 0.48, P = 0.046). No relationship was found between lumen area and vessel wall thickness (P = NS), but outer wall area increased significantly with vessel wall thickness at 19 mm 2 per mm (P = 0.046). This is consistent with outward vessel wall remodeling. Conclusion: Despite the small size of our healthy cohort, using high-resolution MR imaging and B2B-RMC, we have demonstrated increasing coronary vessel wall thickness and W/OW with age. The results obtained are consistent with outward vessel wall remodeling. Copyright © 2011 Wiley-Liss, Inc.

Scott A.D.,Imperial College London | Scott A.D.,Cardiovascular Magnetic Resonance Unit | Keegan J.,Imperial College London | Keegan J.,Cardiovascular Magnetic Resonance Unit | And 2 more authors.
Journal of Magnetic Resonance Imaging | Year: 2011

Purpose To quantitatively assess the performance and reproducibility of 3D spiral coronary artery wall imaging with beat-to-beat respiratory-motion- correction (B2B-RMC) compared to navigator gated 2D spiral and turbo-spin-echo (TSE) acquisitions. Materials and Methods High-resolution (0.7 × 0.7 mm) cross-sectional right coronary wall acquisitions were performed in 10 subjects using four techniques (B2B-RMC 3D spiral with alternate (2RR) and single (1RR) R-wave gating, navigator-gated 2D spiral (2RR) and navigator-gated 2D TSE (2RR)) on two occasions. Wall thickness measurements were compared with repeated measures analysis of variance (ANOVA). Reproducibility was assessed with the intraclass correlation coefficient (ICC). Results In all, 91% (73/80) of acquisitions were successful (failures: four TSE, two 3D spiral (1RR) and one 3D spiral (2RR)). Respiratory efficiency of the B2B-RMC was less variable and substantially higher than for navigator gating (99.6 ± 1.2% vs. 39.0 ± 7.5%, P < 0.0001). Coronary wall thicknesses (± standard deviation [SD]) were not significantly different: 1.10 ± 0.14 mm (3D spiral (2RR)), 1.20 ± 0.16 mm (3D spiral (1RR)), 1.14 ± 0.15 mm (2D spiral), and 1.21 ± 0.17 mm (TSE). Wall thickness reproducibility ranged from good (ICC = 0.65, 3D spiral (1RR)) to excellent (ICC = 0.87, 3D spiral (2RR)). Conclusion High-resolution 3D spiral imaging with B2B-RMC permits coronary vessel wall assessment over multiple thin contiguous slices in a clinically feasible duration. Excellent reproducibility of the technique potentially enables studies of disease progression/regression. © 2010 Wiley-Liss, Inc.

Parsai C.,Cardiovascular Magnetic Resonance Unit | Parsai C.,Cardiology and CMR Unit | Ohanlon R.,Cardiovascular Magnetic Resonance Unit | Ohanlon R.,BlackRock | And 4 more authors.
Journal of Cardiovascular Magnetic Resonance | Year: 2012

Cardiovascular Magnetic Resonance (CMR) is recognised as a valuable clinical tool which in a single scan setting can assess ventricular volumes and function, myocardial fibrosis, iron loading, flow quantification, tissue characterisation and myocardial perfusion imaging. The advent of CMR using extrinsic and intrinsic contrast-enhanced protocols for tissue characterisation have dramatically changed the non-invasive work-up of patients with suspected or known cardiomyopathy. Although the technique initially focused on the in vivo identification of myocardial necrosis through the late gadolinium enhancement (LGE) technique, recent work highlighted the ability of CMR to provide more detailed in vivo tissue characterisation to help establish a differential diagnosis of the underlying aetiology, to exclude an ischaemic substrate and to provide important prognostic markers. The potential application of CMR in the clinical approach of a patient with suspected non-ischaemic cardiomyopathy is discussed in this review. © 2012 Parsai et al.; licensee BioMed Central Ltd.

PubMed | Cardiovascular Magnetic Resonance Unit
Type: Review | Journal: Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance | Year: 2016

There were 116 articles published in the Journal of Cardiovascular Magnetic Resonance (JCMR) in 2015, which is a 14 % increase on the 102 articles published in 2014. The quality of the submissions continues to increase. The 2015 JCMR Impact Factor (which is published in June 2016) rose to 5.75 from 4.72 for 2014 (as published in June 2015), which is the highest impact factor ever recorded for JCMR. The 2015 impact factor means that the JCMR papers that were published in 2013 and 2014 were cited on average 5.75 times in 2015. The impact factor undergoes natural variation according to citation rates of papers in the 2 years following publication, and is significantly influenced by highly cited papers such as official reports. However, the progress of the journals impact over the last 5 years has been impressive. Our acceptance rate is <25 % and has been falling because 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. For this reason, the Editors have felt that it is useful once per calendar year to summarize the papers for the readership into broad areas of interest or theme, so that areas of interest can be reviewed in a single article in relation to each other and other recent JCMR articles. The papers are presented in broad themes and set in context with related literature and previously published JCMR papers to guide continuity of thought 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 papers to JCMR for publication.

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