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Ebook Cardiovascular magnetic resonance: Part 2

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(BQ) Part 1 book Cardiovascular magnetic resonance presents the following contents: Tumours and masses, valve disease, pericardial disease, congenital heart disease, aortic disease, peripheral arteries, coronary magnetic resonance imaging, systemic and pulmonary veins, extracardiac findings, new horizons for CMR.

Chapter Tumours and masses Introduction 214 General scanning technique 216 Identifying cardiac masses 220 CMR features suggesting malignancy 222 Non-tumourous masses 224 Benign cardiac tumours 226 Malignant cardiac tumours 230 213 214 CHAPTER Tumours and masses Introduction Cardiac tumours are rare – 70.1–0.3% at autopsy, many of which may be incidental findings Benign tumours and other masses are far more common than malignant tumours, and of the malignancies, metastases are many times more common than primary cardiac tumours Masses in or around the heart can be seen on echocardiography or CT and further investigation is required to separate artefact and innocent structures from true masses potentially of concern to the patient and clinician CMR is highly valuable in the assessment of cardiac masses, due to its versatility in image planes and excellent ability to discriminate tissue types based on their MR properties, and their response to gadolinium contrast CMR can differentiate normal from abnormal myocardium, identify the size, location, and anatomy of a mass, and can often provide a likely diagnosis While CMR may not always provide a definitive pathological diagnosis, it can usually identify abnormal tissue and determine the likelihood of a tumour based on the characteristics of the mass It may also guide surgery and/or biopsy, if this is deemed appropriate This page intentionally left blank 216 CHAPTER Tumours and masses General scanning technique A high degree of adaptability is required when imaging cardiac masses, given their wide variation in size and location, and several non-standard imaging planes are often required Gadolinium contrast is important for characterizing any mass and should be given unless contra-indicated If assessment of calcification is needed, consider CT Basic scanning protocol There will be significant variability in what images are needed, depending on the nature of the mass A general scheme is provided here (see also Fig 9.1) • Standard orthogonal thoracic imaging: standard body planes (e.g with a HASTE sequence), covering the entire mediastinum This provides a good overview of the anatomy and can identify larger masses • LV and RV function assessment: long axes plus a short axis stack (SSFP cine sequences), provides full coverage of both ventricles, and also an assessment of the functional consequences of any mass Look for motion of the mass, impairment of myocardial contraction, or obstruction to flow • ± Thin-slice transaxial cine images: imaging the specific region where a mass is identified/suspected can be helpful in determining the presence of a mass and its motion Use thin slice (4–6mm) transaxial (±coronal/sagittal) cine images, without a gap If necessary, the entire heart can be covered, checking for additional findings (e.g metastases) • ± Other cine images as required: non-standard image planes are commonly required, to fully visualize the anatomy and extent of a mass Plan these from existing images demonstrating the mass, ensuring at least two (preferably three) perpendicular planes through the mass to visualize the extent in all directions • Turbo spin echo images: acquire T1-weighted (with or without fat sat), as well as T2-weighted images (preferably triple inversion recovery, with blood and fat suppression) in the same slice positions as SSFP or in representative slices • ± Tagging: tagging may be applied to further characterize the functional consequences of tissue infiltration (lack of mobility), if required • ± Perfusion imaging or angiography: administering gadolinium using a perfusion technique can determine the blood supply/vascularity of a suspected cardiac mass Choose or representative image positions that best demonstrate the mass 3D MR angiography can be helpful if infiltration of nearby vascular structures is suspected or for characterizing any feeding vessels • Early gadolinium imaging: good for identifying thrombi (either adherent to the mass, or may also be the mass itself; Fig 9.2) T1-weighted imaging may also be used to characterize any uptake of gadolinium by the mass • Late gadolinium enhancement: identifies areas of sequestration of the contrast within the mass and/or fibrosis/necrosis GENERAL SCANNING TECHNIQUE (a) (b) * * (c) (d) * * (e) (f) * * (g) (h) * * Fig 9.1 Example of an approach to imaging masses A large RV tumour is present (a malignant melanoma metastasis), imaged in the RVOT view (left: a,c,e,,g) and the HLA view (right: b,d,f,h) Top panels (a,b) show SSFP sequences; the tumour (*) is almost isointense to myocardium and can be seen obstructing the RVOT (a) There is a moderate pericardial effusion - a marker of malignancy (c,d) Early images from the perfusion sequence, with contrast in the blood pool outlining the mass (*) (e,f) Later images from the perfusion sequence demonstrating uptake of contrast in the mass, though heterogenous in part (g,h) Late gadolinium enhancement images showing patchy persistence of gadolinium, particularly in the centre of the mass, suggestive of central necrosis 217 218 CHAPTER Tumours and masses Reporting should include: • Confirmation of the presence or absence of a mass • Description of the anatomical relationships of the mass, and whether there is infiltration into adjacent tissues or pericardium • Whether the mass appears to arise from the heart/myocardium or elsewhere in the mediastinum? See b p 440 for mediastinal masses • Any additional masses or lung metastases • The motion of the mass and its functional significance, e.g valve or pulmonary artery obstruction • Description of the signal characteristics on differing sequences, and contrast enhancement patterns (perfusion, early, and late) • Assessment of likely diagnoses and criteria that may suggest malignancy, taking into account the whole picture CMR cannot offer a histological diagnosis, but can provide strong clues to guide further management GENERAL SCANNING TECHNIQUE Fig 9.2 Early gadolinium imaging images in the LVOT view (left) and short axis view (right) demonstrating two separate thrombi (arrowed) in the same patient The low signal intensity of the thrombus is highlighted by the intermediate to high signal from the blood pool and myocardium 219 220 CHAPTER Tumours and masses Identifying cardiac masses When assessing cardiac masses, a consideration of the full differential diagnoses is important, particularly given the rarity of cardiac tumours Normal cardiac structures should be differentiated from abnormal masses, and non-neoplastic diagnoses for the latter should be explored - the most common non-tumourous mass is cardiac thrombus, which can usually be easily differentiated with CMR Cardiac ‘masses’ can be categorized into three groups: • Normal structures • Benign masses: • Non-tumourous masses (e.g thrombus, infective vegetation) • Benign cardiac tumours • Malignant: • Cardiac metastases (30–40 times more likely than 1° tumours) • Primary malignant cardiac tumours The following are considered in separate chapters: • Mediastinal masses, b p 440 • Pericardial masses, b p 304 Normal cardiac structures commonly confused with masses Moderator band in the RV This can appear as an apical mass, especially if a degree of RV hypertrophy is present The proximity of the apex to the echocardiographic transducer on an apical 4-chamber view increases the echogenicity of the moderator band, which can appear as a mass It should be recognized by its location, connecting the RV free wall to the septum and the relatively uniform thickness along its length The ‘warfarin’ ridge in the left atrium This rim, between the left upper pulmonary vein and left atrial appendage, can be prominent in some subjects (Fig 9.3) It is known as the ‘warfarin’ ridge (due to its possible misinterpretation as thrombus on echocardiography), and can appear as a mass, especially if viewed in cross-section It can usually be recognized by its elongated nature, sometimes with a rolled tip (the ‘Q-tip’ sign, after the brand of cotton buds this resembles) and by its continuity with the left atrial wall Eustachian valve/Chiari network/crista terminalis in the right atrium The Eustachian ‘valve’, a vestigial remnant from in utero life, is a ridge of tissue attached to the inferior right atrial wall just above the inferior vena cava (IVC), directing blood from the IVC towards the foramen ovale (Fig 9.4) It can be mistaken for a vegetation or mass, though can usually be recognized by its elongated nature and location of attachment A Chiari network of fine web-like strands can be attached to the tip of the Eustachian valve or to the adjacent RA wall It is highly mobile, with a whiplike motion, and is sometimes mistaken for an infective vegetation The crista terminalis is a ridge of tissue between the SVC and right atrial appendage IDENTIFYING CARDIAC MASSES Fig 9.3 Oblique coronal SSFP image showing a prominent warfarin ridge (thick arrow) between the left upper pulmonary vein (LUPV) and the left atrial appendage (LAA) The tip is bulbous, exhibiting the ‘Q-tip’ sign Fig 9.4 Oblique coronal view through the right atrium (RA), showing the IVC, and a prominent Eustachian valve (long arrow) directed towards the atrial septum (arrowhead) 221 222 CHAPTER Tumours and masses CMR features suggesting malignancy There are no specific features diagnostic of malignancy, but several aspects visualized well with CMR can suggest malignancy is more likely (below) Some tumours also have typical features, which are covered in subsequent sections Tumour characteristics • • • • • • Large size Extension beyond one cardiac chamber Pericardial involvement: nodular thickening, effusions Invasion through tissue planes Multiple lesions (within the heart, pericardium, or lungs) Location (can be typical for individual masses) MR characteristics • Regional cardiac dysfunction • Signal heterogeneity, especially if areas of: • Haemorrhage (variable signal depending on the age of haemorrhage) • Necrosis (low signal on T1-WI and high on T2-WI) • Haemorrhagic pericardial effusion (high T1 signal) Specific signal characteristics • Most cardiac masses share a common pattern, limiting the diagnostic value of the signal pattern: • Low to intermediate on T1-WI • Intermediate to high signal on T2-WI • Some masses differ from this, however: • Low T2 signal – fibroma/fibroelastoma, metastatic malignant melanoma • High T1 signal – lipoma, haemorrhage in a malignant mass, metastatic malignant melanoma This page intentionally left blank 462 CHAPTER 18 New horizons for CMR Non-contrast myocardial perfusion imaging Using arterial spin labelling methods, it may, in future, be possible to assess perfusion without the use of first-pass MR contrast techniques These methods already work well experimentally at high field (7–12T), but remain to be established at current, clinically used field strengths This would allow assessment of perfusion in patients with contraindications to MR contrast agents, and provide a tool for investigating dynamic changes in perfusion Myocardial oxygenation Using the blood oxygenation level dependent (BOLD) effect, CMR can potentially assess myocardial tissue oxygenation Deoxygenated haemoglobin in blood acts as an intrinsic contrast agent, changing proton signals in a fashion that can be imaged to reflect the level of blood oxygenation Increases in O2 saturation increase the BOLD imaging signal (T2 or T2*), whereas decreases diminish it It is possible that, compared with perfusion, cardiac tissue de-oxygenation may be a superior parameter reflecting more directly the imbalance between oxygen demand and supply that characterizes ischaemia (Fig 18.1) Although the feasibility of the technique at 1.5T has been demonstrated, implementation of the cardiac BOLD approach is fundamentally limited by the relatively small difference in the signal between normal and deoxygenated myocardial regions Higher field strength (3T) combined with new robust steady-state free precession (SSFP) techniques that generate T2-weighted images of the heart overcomes some of these problems Molecular imaging This method has huge potential for the future Contrast agents for molecular imaging have to be manufactured, and typically include a ligand with affinity and specificity for a molecular target (e.g fibrin), a carrier particle and a signalling element, which for MR imaging is either gadolinium (signal increase) or iron (signal increase or decrease) Regulatory approval of such new compounds will be an additional hurdle In future, targeted molecular imaging may accelerate and refine diagnosis, provide more precise disease characterization, enable specific treatments to be targeted in individual patients, enable drug delivery to site of pathology, and monitor responses to treatment MOLECULAR IMAGING 110 Stress 105 Rest Signal intensity (AU) 100 95 90 85 80 75 70 65 60 ISEP ASEP ANT ALAT ILAT INF 95 Signal intensity (AU) 90 85 Stress 80 Rest 75 70 65 60 55 50 45 40 ISEP ASEP ANT ALAT ILAT INF Fig 18.1 Oxygenation imaging with BOLD T2-weighted signal intensity values at rest and stress (Top panel) Normal volunteer, showing an increase in signal intensity with stress for all myocardial segments (Bottom panel) A patient with significant stenosis of a dominant right coronary artery, showing no change or even d signal with stress in the inferior septum, and inferior and inferolateral walls ISEP = inferior septum; ASEP = anterior septum; ANT = anterior wall; ALAT = anterolateral wall; ILAT = inferolateral wall; INF = inferior wall; AU = arbitrary units 463 464 CHAPTER 18 New horizons for CMR Magnetic resonance spectroscopy While CMR imaging uses the 1H nucleus in water and fat molecules as a signal source, cardiac MR spectroscopy (MRS) allows the study of many other nuclei, such as 13C, 23Na, and 31P, thereby allowing insights into many aspects of cardiac metabolism MRS is the only available method for the non-invasive assessment of cardiac metabolism without the need for external radioactive tracers and in theory, it could allow many important clinical questions to be answered Major clinical research applications are heart failure, ischaemia, cardiomyopathies, diabetes, obesity, and valve disease However, the signals acquired in MRS are 100,000–1,000,000 times weaker than the signals used in MR imaging Therefore, the temporal and spatial resolution of MRS is poor (e.g 31P MRS of the heart requires a 30ml voxel size and a 30min acquisition time) At the moment, the method is an important research tool that can be used to detect differences between study groups, but because of its high variability, is not reliable for the assessment of individual patients Future developments will include: • • • • Improvements in coil design (phased array with optimized geometries) Improvements in sequence design Higher field strength (7T and more) Hyperpolarization methods (see below) With these improvements, cardiac MRS may eventually become a clinically valuable method Dynamic nuclear polarization methods Hyperpolarization of nuclear spins can boost the MR signal by a factor of up to 100,000 The most important application for the heart is dynamic nuclear polarization (DNP) of 13C A liquid 13C-containing compound, e.g 13 C-pyruvate (Fig 18.2) is frozen and irradiated by microwaves in a magnetic field The sample is then rapidly thawed and injected quickly as the DNP state is short lived (minutes) Potential applications • 13 C-MRS of pyruvate allows analysis of various metabolic pathways (e.g pyruvate dehydrogenase) • 13C-MRI following intracoronary bolus of 13C-urea for coronary angiography • Tissue pH imaging using 13C-bicarbonate DYNAMIC NUCLEAR POLARIZATION METHODS Thermal equilibrium Hyperpolarized Fig 18.2 13C-MR spectra of pyruvate at 9.4T Compared with the normal thermal equilibrium spectrum, the hyperpolarized spectrum shows a signal increase of >22,000 times Courtesy of Drs Damian Tyler and Lowri Cochlin, Department of Physiology, Anatomy, and Genetics, Oxford University Further reading Choudhury, RP, Fuster, V, Fayad, ZA Molecular, cellular and functional imaging of atherothrombosis Nat Rev Drug Discov 2004; 3(11): 913–25 Friedrich, MG, Niendorf, T, Schulz-Menger, J, Gross, CM, Dietz, R Blood oxygen level-dependent magnetic resonance imaging in patients with stress-induced angina Circulation 2003; 108: 2219–23 Kober, F, Iltis, I, Cozzone, PJ, Bernard, M Myocardial blood flow mapping in mice using high-resolution spin labeling magnetic resonance imaging: influence of ketamine/xylazine and isoflurane anesthesia Magn Reson Med 2005; 53: 601–6 Merritt, ME, Harrison, C, Storey, C, Jeffrey, FM, Sherry, AD, Malloy, CR Hyperpolarized 13C allows a direct measure of flux through a single enzyme-catalysed step by NMR PNAS 2007; 104: 19773–7 Robson, MD, Tyler, DJ, Neubauer, S Ultrashort TE chemical shift imaging (UTE-CSI) Magn Reson Med 2005; 53: 267–74 Ten Hove, M, Neubauer, S MR spectroscopy in heart failure–clinical and experimental findings Heart Fail Rev 2007; 12: 48–57 465 This page intentionally left blank 467 Index Page numbers in italics refer to figures and tables A abdominal abnormalities 456 abdominal fluid 456 acquisition window, triggering from ectopic beats 54 acute coronary events 156, 174, 194 adenosine stress perfusion imaging 121, 164, 166 adenosine stress and rest 169 adrenal masses 456 aliasing 138 correction during postprocessing 139 flow analysis 138 alveolar fluid 430 proteinosis 432 amiodarone toxicity 430 amyloidosis 202, 203 parenchymal lung disease 430 anaemia 444 anaesthesia, general anaesthesia 64 Anderson-Fabry disease 190, 191, 430 aneurysm, atrial septum 322, 323 angiography digital subtraction angiography (DSA) 384–6 editing techniques 142, 143 see also magnetic resonance angiography angioplasty, patch 378 angiosarcomas 230 anthracycline chemotherapeutic cardiomyopathy 198 anxiety, patient 42 aorta bypass graft 378 congenital variants 380, 381 development in utero 372 MR angiography 360, 361, 374, 375 oblique sagittal plane multi-slice image 78 to right pulmonary artery, Waterston shunt 347, 354 aortic arch cervical 380, 381 congenital hypoplasia 252 congenital variants 380 right-sided 380, 381 aortic coarctation 238, 372–80, 373 causes 372 differential diagnosis 376 and dilatation 364 guide to severity 376 high velocity jet 373 MR angiography 374, 375 post-surgery/ intervention 363 aortic diameters, indexed to body surface area 365 aortic dilatation 362, 363 and coarctation 372 imaging 362 aortic disease 355–80 aortic dissection 366–70 differential diagnosis 368 post type A repair 367, 370–71 aortic root replacement with valve resuspension 370 aortic valve and root replacement graft 370 interpositional graft 370, 371 Stanford classification 367 thrombus in false lumen 366 visible flap 366, 369 aortic flow, flow—time curve 137, 138 aortic imaging 356–60 aortic dilatation 362 MR angiography 360, 361, 365 non-standard planes 356 normogram showing aortic diameters indexed to body surface area 365 parallax error 363 standard imaging techniques 358, 359, 361 aortic regurgitation 240 assessment of severity 243 quantification 242, 243 reduced leaflet coaption 362 reporting 242 underestimation 243, 242–3 aortic stenosis 244 assessing severity 249, 249 differential diagnosis 248 LVOT view 245 ‘Prussian helmet’ sign 245 aortic valve 239, 238–54 bicuspid aortic valves 139, 238, 239, 362, 372 ‘en-face’ view 246 planimetry of a stenotic valve area 236, 247 quadricuspid aortic valves 238 tricuspid aortic valve 245 velocity aliasing 139 aortic wall imaging 360, 390 intramural haematoma 361, 363, 368 aorto-pulmonary collateral arteries, major (MAPCAs) 346 apical displacement, tricuspid leaflets 328 apical fat pad 224 Argus software 133 arrhythmias 54, 104 specific cine sequences 55 arrhythmogenic right ventricular cardiomyopathy 184, 185 diagnostic criteria for ARVC 187 scanning and reporting 186 artefacts 26 blurring/mistriggering 168 breast implants 48, 448, 449 dark rim artefact 168, 169 field of view 26, 27 gating 28, 29 metal surgical clips 379 metallic components 288 metallic prosthetic aortic valve 371 468 INDEX moiré fringes (zebra stripe) 45 motion 28, 29 breathing motion 28 children 62 parallel imaging 28, 29 screening ferrous objects 36 signal-to-noise ratio 26, 27 spinal 447 steady state free precession (offresonance) 28, 29 susceptibility 26, 26, 168 arterial spin labelling, non-contrast myocardial perfusion imaging 462 arterial switch 336 Jatene procedure 336, 352 with Lecompte manoeuvre 341, 354 arteriovenous malformations 394, 434 magnetic resonance angiography (MRA) 434 arteritis, Takayasu’s, of aorta 361 atherosclerotic plaque anatomy and composition 390 aortic wall 361 MR signal characteristics 391 atomic nuclei atria, identifying 315 atrial appendages, anatomical connections 315 atrial baffle 338 atrial fibrillation (AF) 54 atrial isomerism, ambiguous connections 314 atrial septal defect 318, 319, 321 left to right shunt 152 atrial septum aneurysm 322, 323 en-face view 321 atrial short axis stack 320 atrioventricular concordance/ discordance 314 atrioventricular septal defect 326, 327 B balloon valvuloplasty 266 Barlow’s disease 258 basal septum, hypertrophy 254 Becker muscular dystrophy 206 Bentall operation 352 bi-leaflet tilting disc valve 289 bicuspid aortic valves 238, 239, 362 aortic coarctation 372 velocity aliasing 139 bioprosthetic (Carbomedics) valve 289 black-blood preparation 22, 75 arrhythmias 54 spin-echo image 21 Blalock-Taussig shunt 352 blood oxygenation level dependent (BOLD) effect, myocardial oxygenation 462, 463 Bochdalek diaphragmatic hernia 438 body mass index 44 Boltzmann distribution 32 bone, metastatic disease 446, 447 Boyle’s machine/ ventilator 64 brachiocephalic vein 410 breast carcinoma 448 breast fibro-adenoma 448 breast implants 48, 448, 449 breath-hold vs non-breathhold scans 58 breathing motion artefacts 28, 29 Brock procedure 352 bronchial carcinoma 442 bronchogenic cysts 442 bypass graft, aorta 378 C calcification mitral valve 264, 267 pericardial 296 ultrashort echo time (UTE) imaging 460 carbon spectroscopy 32, 33 carcinoma 434 adrenal 456 breast 448 bronchial 442 embryonal 440 hepatocellular 450 pancreas 454 cardiac BOLD approach 462, 463 cardiac coils, size of FOV 40 cardiac (ECG) gating 28, 46 choice of trigger 46, 47 preparation of patient 46 prospective vs retrospective triggering/gating 52, 53 types of triggering/ gating 50 see also ECG cardiac failure, pulmonary oedema 430 cardiac hypertrophy basal septum 254 see also left/right ventricular hypertrophy cardiac motion 16, 17 compensation 402, 403 cardiac sarcoidosis 160, 200, 201, 224 cardiac spectroscopy and non-proton imaging 32 cardiac vegetations 266, 286 cardiomyopathy chemotherapy 198 inheritable 178–90 see also dilated -; hypertrophic cardioverterdefibrillators 66 carotid arteries, wall imaging 390, 391 carotid disease carotid stenosis 388 digital subtraction angiography (DSA) 384–6 localizer sequence showing slice positions 389 maximum intensity projection (MIP) 389 cavernous haemangioma 446, 447 cervical aortic arch 380, 381 chemotherapy, cardiomyopathy 198 Chiari network 220 children 62–3 general anaesthesia 64–5 chordae 256 chronic haemolytic anaemia 444 cine imaging 24, 25, 60, 74, 75 ultra-fast 56, 74 whole heart 4D cine CMR 460 see also steady state free precession (SSFP) cine imaging classical theory, RF pulse claustrophobia 42 common bile duct (CBD), dilatation 454 congenital heart disease 310–52 INDEX CMR approach 312 sequential segmental approach to diagnosis 314 congenital hypoplasia, aortic arch 252 congenital variants, aorta 380 contractile dysfunction, wall motion abnormalities 156 contrast agents 30 contrast-enhanced MR angiography 81, 116, 117 cor triatriatum 266 coronal plane multi-slice image 78, 79 coronary angiography 174 coronary arteries anomalous origins 406, 407 imaging ischaemic heart disease 174 see also coronary magnetic resonance imaging; magnetic resonance angiography (MRA) normal origins 400, 401 coronary artery disease acute coronary events 156, 174, 194 ischaemic heart disease 174 LAD stenosis 169, 171 myocardial time-intensity curves 171 coronary magnetic resonance imaging 400–6 2D or 3D sequences 405 anomalous coronary artery origins 406, 407 cardiac motion compensation 402, 403 fat saturation pulses 400 high resolution static images 400 individual coronary imaging 404 intravascular contrast agents 400 whole heart imaging 405 coronary sinus defect 318 crista terminalis 220 cryocooler/compressor cysts 224, 225 D Damus Kaye Stansel operation 352 dark-blood see black blood preparation delayed gadolinium enhancement see late gadolinium enhancement dextrocardia 316 diaphragm 438 eventration 438 hernias 438 paralysis 438, 439 rupture 438 DICOM-based imaging 132 DiGeorge syndrome 344 digital subtraction angiography (DSA) 384–6 dilated cardiomyopathy 160, 182, 183 differential diagnosis 182 dipyridamole 121 dobutamine stress CMR 121 contraindications 165 High dose vs low dose infusion protocols 165 double outlet right ventricle 334, 335 Duchenne muscular dystrophy 206 ductus arteriosus fibrosis 372 persistent 346 dynamic LVOT obstruction 254, 255 dynamic nuclear polarization methods 464, 465 E Ebstein anomaly 328, 329 ECG interpretation within magnet 50 lead placement on back 48 lead positioning 49 leads and cables 48 magneto-hydrodynamic effect 50 problems 50 distortion due to gradient interference 51 electrode becoming detached 51 inverted R wave 51 triggering/gating 52, 53 see also cardiac (ECG) gating echo time (TE) 19 spin echo acquisition 20 echo-planar imaging (EPI) 36 ectopic beats 54 editing techniques, angiography 142, 143 Eisenmenger syndrome 321 electrode positioning 48 embryonal carcinomas 440 empyema 436 enhancement imaging, gadolinium contrast 20, 21 eosinophilic myocarditis 204, 205 differential diagnosis 204 differentiation from ischaemic heart disease 160 Eustachian valve, right atrium 220, 221 extracardiac findings 426–56 extramedullary haemopoesis 444, 445 extramedullary plasmacytoma 444 F Fabry’s disease 190, 191, 430 Fallot’s tetralogy 274, 330, 331, 333 Fast Low Angle Shot (FLASH) sequence 22, 24 fat necrosis 448 fat saturation 22, 98, 99 fatty infiltration, liver 450 ferrous objects, screening 36 fibroadenomas 448 fibroma/fibroelastoma 222, 226, 227 flail, mitral valve leaflets 258–9 flow analysis 136, 137 aliasing 138 avoiding turbulence 136 background correction 138 in-plane flow sequences 140, 141 normal flow-time curve from aortic valve 137 through-plane phase velocity mapping sequences 136 flow imaging 100, 101 in-plane velocity mapping 100, 101 partial volume effects 100 phase shift errors 102 through-plane velocity mapping 101, 102 flow—time curve 137, 138 aortic and pulmonary flow 138 using pulse oximetry triggering 139 fluid—fluid interfaces 456 Fontan circulation 348, 349 469 470 INDEX Fontan operation 352 foramen ovale, patent 322 Fourier transformation 10, 11 K-space 10, 11 free-breathing imaging, pericardial constriction 56 frequency encoding, vs phase encoding 10 future developments in CMR 460–4 G gadolinium contrast 30, 106, 107 brands and properties 31 late enhancement, see late gadolinium enhancement short axis image during first-pass perfusion 23 gallbladder, abnormalities 456 gallstones 457 gating see cardiac (ECG) gating general anaesthesia 64 children 64–5 germ cell tumours 440 Glenn shunt 350, 352, 353 glossary, surgical procedures 352 glycogen storage diseases 431 gradient echo 74 multi-slice image 74 spoiled 74 gradient switching and high gradient amplitude 36 granulomatous disease 434, 435 great arteries, see also transposition of great arteries great vessels, arrangement 316, 337 H haemangiomata 450 haematoma aortic wall 368 intramural, aortic wall 361, 363 haemochromotosis, iron-loading 430, 431 haemopoesis, extramedullary 444, 445 haemorrhage 448 in malignant mass 222 Half-Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) 20, 74, 77, 79 oblique sagittal plane multi-slice image 78, 79 head and neck high resolution T2weighted transverse CMR 391 vessels 388–90 hepatic cyst 450, 451 hepatocellular carcinoma 450 hiatus hernia 444, 445 hilar lymphadenopathy 441 Hurler’s disease 430 hydatid disease 224 hyperdynamic LV contraction 254 hypertrophic cardiomyopathy 160, 178 differential diagnosis 180 late gadolinium enhancement 178, 179 LV outflow or mid-cavity obstruction 178 LVOT obstruction 254 obliteration of the LV cavity in systole 178 regional ‘asymmetric’ 178, 179 scanning and reporting 180 I iliac and leg arteries 394, 395 image acquisition 72–120 acquisition window, triggering from ectopic beats 54 avoiding partial volume effects 96, 97 importance of operator interaction 72 options for image positioning 96, 97 ‘standard’ CMR dataset 72, 73 static image 74, 75 time reduction 56 unusual image planes 96 image generation Fourier transformation 10, 11 frequency encoding vs phase encoding 10 identification of signal from position within slice 10 magnetic field gradients 98 repeated signal acquisitions 10 representation of image slice through vessel 13 resolution 12 ‘sequences’ 12 time 12 image positioning, unusual image planes 96, 97 image processing 128–142 angiography and other 3D datasets 142 flow analysis 136 ventricular volume and function analysis 128 implantable cardioverterdefibrillators 66 in-plane flow sequences 140, 141 in-plane velocity mapping 100, 101 inferior vena cava (IVC), connection to right atrium 410, 411 inheritable cardiomyopathies 178–90 innominate (brachiocephalic) vein 410 interstitial lung disease 435 interventricular septum, motion 152 intravascular contrast agents 30 inversion time (TI) 20 recovery 74 iron oxide particles, contrast agent 30 iron-loading haemochromotosis 430, 431 overload 208, 209 ischaemic heart disease 156–174 contractile dysfunction: wall motion abnormalities 156 coronary artery imaging 174 differential diagnosis 160 dobutamine stress CMR 164 multiparametric CMR approach 174, 175 myocardial viability 162 oedematous myocardium, in acute coronary events 156, 157 perfusion imaging 166 scanning and reporting 158 INDEX J Jatene procedure 336 arterial switch 352 K K-space 10, 11 Konno operation 354 L Larmor frequency/ equation 32 late gadolinium enhancement (LGE) 20, 21, 112, 113–15, 342 myocardial infarction 156, 157, 159, 162, 163 myocardial tissue characterization 194 lead positioning 49 Lecompte manoeuvre, with arterial switch 341, 354 left superior vena cava 412, 413 left to right shunt, atrial septal defect 152 left ventricle, identifying 315 left ventricular function 80–8 17 segment model (AHA) 147 analysis using Argus software 133 assessment 146 asymmetric hypertrophy 146 tagging and reporting 146 basal slice 128, 129 basal slice positioning 88 hyperdynamic contraction 254 LV outflow tract view ± ‘coronal’ LVOT cine 86, 87 normal ranges of LV volumes, ejection fraction and mass 147 pilot (scout) images 80, 81 segmental wall thickening 146 short axis cine stack 88, 89 standard views 80 horizontal long axis view 82, 83 vertical long axis view 84, 84–5 left ventricular noncompaction 188, 189 differential diagnosis 188 left ventricular outflow tract aortic regurgitant jet 241 aortic stenosis 245 congenital membrane 250, 251 dynamic obstruction 254, 255 supravalvar stenosis 253 differential diagnosis 254 leg arteries 394, 395 leiomyosarcoma 232 lipoid pneumonia 432 lipoma 222, 228, 448 pericardial 304, 305 lipomatous hypertrophy of the intra-atrial septum 228, 229 liposarcoma 232 liver 431, 450 cirrhosis 450 cirrhosis-induced portal hypertension 457 fatty infiltration 450 haemangiomata 450 polycystic disease 451 simple cysts 450, 451 uncertain lesion 451 localizers (scout) images 76 longitudinal relaxation (spin-lattice relaxation time) Lorentz force 50 lung fibrosis 430, 432 LVtools® software 134 lymph nodes and lymphoma 440 lymphadenopathy 440, 441 lymphoma, primary 232, 233 M magnet, superconducting magnetic fields gradient switching and high gradient amplitude 36 gradients 96, importance of a homogeneous field 14 safety issues 14, 15, 36, 39 magnetic resonance angiography (MRA) 142, 384 aorta 360, 361, 374, 375 aortic coarctation 374, 375 AV malformations 434 contrast-enhanced methods 384 coronary arteries 174 editing techniques 142, 143 head and neck vessels 388–90 ‘maximal intensity projection’ (MIP) 142 non-contrast techniques 384 raw data as multiple contiguous 2D planes 142, 143 scanning and reporting 386 subclavian and vertebral arteries 388 surface rendering 142 surface-rendered contrast 416 magnetic resonance cholangiopancreatography (MRCP) 456 magnetic resonance imaging (MRI) gradient system 6, principles magnetic resonance spectroscopy (MRS) 464 magnetization recovery magneto-hydrodynamic effect, ECG 50 major aorto-pulmonary collateral arteries (MAPCAs) 346 malignant tumours 222, 230, 233, 434 intramyocardial metastasis 231 locations 231 melanoma metastasis 217, 230 pericardial 304 malignant ventricular arrhythmias 406 manufacturers, major, sequence branding 75 Marfan syndrome 365 masses see tumours and masses ‘maximal intensity projection’ (MIP) 142 mediastinal masses 440 mesothelioma 436 metal artefacts prosthetic aortic valve 371 screening ferrous objects 36 surgical clips 379 metastatic disease 434, 450 bone 446, 447 microvascular obstruction 162, 163 mitral regurgitation 258 assessment of severity 261 ‘functional’ 261 quantification 260, 261 reporting 262 mitral stenosis 264, 265 471 472 INDEX assessment of severity 267 degenerative (calcific) disease 264 mitral valve 257, 256–64 bowing, prolapse or flail? 259 calcification 267 flail leaflets 258–9 ‘hockey stick’ appearance 265 leaflet mobility 267 morphology, Wilkins scoring system 267 regurgitation 258, 259 sub-valvar thickening 267 moiré fringes (zebra stripe) 45 molecular imaging 462 Morgagni diaphragmatic hernias 438 motion artefacts 28, 29 children 62 MR angiography see magnetic resonance angiography MRI see magnetic resonance imaging mucopolysaccharidoses 430 multicystic degeneration of thyroid (MCDT) 440, 441 multiparametric CMR approach to IHD 174, 175 multiple myeloma 444 muscle sarcoma 448 muscular dystrophies 206, 207 Mustard operation 339, 354 myasthenia gravis, thymoma 440 myelodysplasia, iron overload 208 myeloma 444 myocardial fibrosis eosinophilic 160 necrosis 194 myocardial infarction late gadolinium enhancement imaging 156, 162, 163 microvascular obstruction 162, 163 viability imaging 156, 157 wall thickness and functional recovery 158 myocardial inflammation and infiltration 296, 194–208 myocardial iron overload 208, 209 myocardial perfusion calculating relative perfusion parameters 170 oxygenation 462 regional 158 reporting 172 reserve index 170 time-intensity curves CAD 171 normal vs CAD 171 myocardial perfusion imaging 120, 123, 166 defects, vs susceptibility artefacts 169 inducible perfusion deficits 156, 172 non-contrast imaging 462 qualitative analysis 168 relative perfusion assessment 170 myocardial viability 162–63 assessment 159 blood flow, absolute quantification 172 and late gadolinium enhancement 162 myocarditis 196, 197, 199 differential diagnosis 198 eosinophilic 204, 205 reporting 198 myocardium oedematous 156, 174, 194, 197 tissue characterization 194 myxoma 226, 227, 266 N ‘navigator’ sequence 59 nephrogenic systemic fibrosis 108 neurofibroma 444 noise, signal to noise ratio (SNR), at 3T, 68 noise levels, at 1.5T during acquisition 36 non-contrast myocardial perfusion imaging 462 non-proton imaging 32 Noonan’s syndrome 274 Norwood operation 354 nuclear polarization methods 464, 465 nuclei, Larmor frequencies O obese patients 44, 45 oblique sagittal plane multislice image 78, 79 oedema imaging acute coronary events 156 myocarditis 196 sarcoidosis 200 oesophageal ‘mass’, hiatus hernia 444, 445 omentum, nodulation 456 orthogonal image planes 76 osteomalacia/ osteoporosis 446 osteosarcoma 232 P pacemakers 66–7 magnetic fields 14 MR-conditional permanent pacemakers 67 retained epicardial pacing wires 66 risk of adverse events 67 pancreas 454 pancreatitis 454 papillary fibroelastoma 226 papillary muscles 130, 256 tricuspid valve 280 paravertebral masses 445 parenchymal lung disease 432 amyloidosis 430 partial volume effects 96, 97 flow imaging 100 patch angioplasty 378 patent foramen ovale 322 patient preparation 40–4 anxiety and claustrophobia 42 breath-hold commands 40 cardiac (ECG) gating 46, 47 children 62–3 clothing 40 ECG lead placement on the back 48 ferromagnetic objects 40 IV access 40 obese patients 44 positioning 40, 41 PCr/ATP ratio 32 perfusion see myocardial perfusion pericardial constriction 300, 301 free-breathing imaging 56 pericardial cysts 224, 225, 302, 303 pericardial effusions 196, 298, 299 pericardial fat pad 442, 443 pericardial recess, superior 442 pericardial tumours 304, 305 pericarditis 296, 297 pericardium 295, 294–306 congenital absence 306, 307 oblique sinus 443 INDEX transverse sinus 368, 369, 443 peripheral arteries 384–94 carotid and aortic imaging 384–6 head and neck vessels 388 iliac and leg arteries 394, 395 renal arteries 392, 393 peripheral nerve stimulation (PNS) 36 peripheral vascular occlusive disease 394 peritoneal cavity, nodulation 456 persistent ductus arteriosus 346 phaeochromocytoma 456 phase encoding, vs frequency encoding 10 phosphocreatine (PCr) 32 phosphorus spectroscopy 32, 33 phrenic nerve paralysis 439 pilot (scout) images 80, 81 plaque see atherosclerotic plaque plasma cell dyscrasias 444 plasmacytoma extramedullary 444 solitary, of bone 444 pleural disease 436 ‘split pleural sign’ 436 pleural effusions 367, 436 layering 436, 437 SSFP vs HASTE imaging 437 pneumonia 432 pneumonitis 432 portal hypertension, cirrhosis-induced 457 post-arterial switch operation 336, 340, 341, 354 post-stenotic dilation, pulmonary artery 277 Pott’s anastomosis shunt 354 precession 52–4 preparation of patient see patient preparation pressure overload, RV 152 prolapse, mitral valve leaflets 258, 259 prosthetic valves 288–91 bi-leaflet tilting disc valve 289 bioprosthetic (Carbomedics) valve 289 Starr-Edwards ball and cage valve 289 TIE-fighter sign 291 proton spectroscopy 32 protons, Larmor frequencies ‘Prussian helmet’ sign 245 pulmonary artery Damus Kaye Stansel operation 352 flow—time curve 138 PA to aortic flow ratio 318 pulmonary atresia tetralogy of Fallot 330 with ventricular septal defect 346, 347 pulmonary bifurcation 333 pulmonary disease 432 in association with cardiac disease 430 pulmonary fibrosis 430, 432 amiodarone toxicity 430 pulmonary hypertension, Eisenmenger syndrome 321 pulmonary hypoplasia, tetralogy of Fallot 330 pulmonary infarction 432 pulmonary jet, turbulence 270 pulmonary nodules/ granulomatous disease 434, 435 pulmonary oedema, cardiac failure 430 pulmonary regurgitation 152, 270, 271, 273 assessment of severity 273 quantification 270 pulmonary sarcoidosis 430 pulmonary stenosis 274, 275 post-stenotic dilation 277 severity 277 supravalvar 152, 278, 279 valvar, sub-valvar 152 veins 422, 423 pulmonary thromboembolism 432, 433 pulmonary valve 268–78 pulmonary veins 416–22 common isthmus of left pulmonary veins 416 drainage, sinus venosus defect 318 partial anomalous pulmonary venous drainage 418, 419 radiofrequency ablation 422 right middle accessory vein 416 scimitar syndrome 418 stenosis 422, 423 surface-rendered contrast angiography 416, 417, 419 total anomalous pulmonary venous drainage 420, 421 pulmonary venous angiography 320 pulse oximetry triggering, flow curve 139 pyruvate, dynamic nuclear polarization 464 Q QMass MR® 133 quantum theory, RF pulse R radiofrequency ablation, within pulmonary vein 422 radiofrequency pulse (RF) 2, pulse energy effects quantum vs classical theory 4, specific absorption rate (SAR) 38 radiofrequency system rapid acquisition relaxation enhancement (RARE) 75 Rastelli post-arterial switch operation 336, 340, 341, 354 ‘real-time’ imaging 56 rectangle (Simpson’s) rule 128, 129 renal arteries 392, 393 renal masses 452, 453 renal transplantation 392 repeated signal acquisitions 10 rhabdomyoma 226 rhabdomyosarcoma 232 rheumatic mitral stenosis 264 right atrium, Eustachian valve/Chiari network/ crista terminalis 220, 221 right ventricle dilated 328 double outlet 334, 335 identifying 315 right ventricular cardiomyopathy 338 arrhythmogenic 184, 185 interpreting wall motion 184 scanning and reporting 186 right ventricular function 90–4 473 474 INDEX 2-chamber view 94, 95 3-chamber view (inflowoutflow’ view) 94, 95 analysis using Argus software 133 assessment 148 reporting 148 scanning 148, 149 transaxial SSFP, free wall contraction 149 basal slice selection 130 causes of RV dilation 153 commercial software packages 132, 133–4 future and post-processing analysis 132 normal ranges of LV volumes, ejection fraction and mass 150 short axis cine stack 90, 148 trabeculations 130 transaxial cine stack 148 volume and pressure overload 152, 153 right ventricular hypertrophy 330 right ventricular outflow tract obstruction 278, 279 pulmonary valve 268, 269 views 92, 93, 149 right ventricular volume, and pressure overload 152, 153 Ross operation 354 S safety issues 36, 39 general anaesthesia 65 magnetic fields 14, 15, 36, 39 MRI scanners 14, 15 safety screening form 37 sagittal plane multi-slice image 78, 79 sarcoidosis 160, 200, 201, 224 oedema imaging 200 pulmonary sarcoidosis 430 sarcomas 230, 448 saturation recovery 22, 23 scanner components 76 scanner noise 12 scimitar syndrome 418 screening ferrous objects 36 safety screening form 37 seminoma 440 senile sigmoid septum 254 Senning operation 354 SENSE factor 26 sequence branding 74 major CMR manufacturers 75 set-up and optimization 36–68 anxiety and claustrophobia 42 arrhythmias 54 at 3.0T 68, 69 breath-hold vs nonbreath-hold scans 58 cardiac (ECG) gating 28, 46, 47 children 62–3 general anaesthesia 65, 64–5 obese patients 44, 45 pacemakers/implantable cardioverterdefibrillators 66–7 reduction of acquisition time 56 safety 36, 39 shimming 14 shunts and conduits 350 sickle cell disease 444 signal generation and ‘relaxation’ Simpson’s rule 128, 129 single ventricle 316, 348 Single-Shot Fast Spin Echo (SS-FSE) 20 Single-Shot Turbo Spin Echo see Half-Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) sinus tachycardia 54 sinus venosus defect ASD 319 pulmonary venous drainage 318 situs inversus, total 315 skeletal abnormalities 446 sodium imaging 32, 33 indicator of myocardial damage 32 soft tissue abnormalities 448 signal characteristics 428 T1-WI and T2-WI 429 solitary plasmacytoma of bone 444 solitary ventricle 316, 348 spin echo acquisition 20 spin precession 23, spin-lattice relaxation time T1, 4, 18 spin-spin relaxation time T2 4, 18, 19 spin dephasing 19 spinal haemangioma 446, 447 spleen, abnormalities 456 splenomegaly 457 ‘standard’ CMR dataset 72, 73 standard orthogonal image planes 76 Starr-Edwards ball and cage valve 289 static MRI sequences 18, 74, 75 tissue contrast 18 steady state free precession (SSFP) cine imaging 24, 25, 38, 44, 51, 56, 58, 60, 62, 68, 69, 146 multi-slice 74, 77 (off-resonance) artefacts 28 sub-aortic stenosis 250 subclavian arteries 388 subclavian flap 378, 379 subclavian veins 410 superconducting magnet superior vena cava (SVC) 410, 411, 415 bilateral SVCs 412, 413 left 412, 413 supra-aortic stenosis 252, 253 supravalvar pulmonary stenosis 278, 279 surface rendering, pulmonary veins 143 surgical procedures, glossary 352 surgical shunts and conduits 350 susceptibility artefacts 26, 26, 168 systemic disease, in association with cardiac disease 430 systemic veins 410–14 occluded 414, 415 T Takayasu’s arteritis, aorta 361 tamponade 298 targeted contrast agents 30 temporary pacing systems 66 teratoma, dermoid 440 tetralogy of Fallot 330, 331, 333 post-repair RVOT 333 thalassaemia, iron overload 208 thalassaemia major 444 thoracic imaging, pre- and post-contrast 428 thoracic vascular anatomy 143 thrombus imaging 163, 224, 225 INDEX early gadolinium imaging 219 left atrial appendage 225 through-plane phase velocity mapping sequences 136 thymoma (thymolipoma) 440 thyroid, multi-cystic degeneration (MCDT) 440, 441 thyroid masses 440, 441 ectopic 443 tissue abnormalities 448 tissue characterization sequences 98, 99 post-contrast 110, 111 total anomalous pulmonary venous drainage 420, 421 total cavopulmonary connection (TCPC) 353 total situs inversus 315 trabeculations left ventricular noncompaction 188, 189 right ventricular 130 transposition of great arteries 337, 339, 336–40 congenitally corrected 342, 343 late gadolinium enhancement 340 post-arterial switch/ Rastelli 336, 340, 341, 354 post-atrial switch operation 338, 339 transverse multi-slice images 76, 77 transverse plane multi-slice images 76, 77 transverse relaxation (spinspin relaxation time) transverse sinus pericardium 368, 369, 443 superior pericardial recess 442 tricuspid leaflets apical displacement 328 CMR features 280–81 tricuspid regurgitation 152, 282, 283, 285, 328, 338 assessment of severity 285 quantification 285 reporting 284 tricuspid stenosis 286, 287 assessment of severity 287 tricuspid valve 281, 280–6 dysplasia 328 triggering/gating 46 prospective vs retrospective 52, 53 truncus arteriosus 344 aortic abnormalities 344 post-corrective surgery 344 tumours and masses 214–30 benign tumours 226 identification 220 malignancy 217,222, 230, 233, 434 mediastinal masses 440 metastatic disease 434, 446, 447, 450 non-tumourous masses 224 paravertebral tumours 444, 445 pericardial tumours 304, 305 scanning technique 216 turbo spin echo 74, 77 echo time (TE) 98 fat saturation 98, 99 gadolinium contrast 98 optimizing sequences 98, 99 repetition time (TR) 98 turbulence 136 flow analysis 136 U ultra-fast cine imaging 56, 74 ultrashort echo time (UTE) imaging 460 uni-ventricular heart 316, 348 unusual image planes 96 V valvular heart disease 236, 237, 238–88 planimetry of a stenotic valve area 236, 247 prosthetic valves 288 see also specific valves vascular anatomy, thoracic 143 vascular fibrosis/calcification, ultrashort echo time (UTE) imaging 460 vascular malformations 394, 434 see also adenosine vegetations 266, 286 velocity aliasing 139 velocity mapping in-plane 100, 101 sequences 136 temporal resolution 102 through-plane phase sequences 136 ventricles assessment 146–152 determining arrangement 314 dilated RA and RV 318 identifying 315 volume, LV volume/ mass 128, 129 ventricular function analysis 128 manual processing 128 semi-automated using LVtools (CMRtools)® 134 ventricular septal defect 324, 325 with pulmonary atresia 346, 347 restrictive and nonrestrictive 325 single ventricle 348 tetralogy of Fallot 274, 330 types 324, 325 ventricular septum, aortic ‘over-ride’ 330 ventricular short axis cine stack 320 ventricular tachycardia, dobutamine stress CMR 164 vertebral arteries 388 vertebral bodies cavernous haemangioma 446, 447 low—intermediate signal intensity 444 vessel wall imaging 390 voxels, 3D pixels 12 W wall motion abnormalities 156 score index 164 ‘warfarin’ ridge 220, 221 Waterston shunt, aorta to right pulmonary artery 347, 354 whole heart 4D cine cardiovascular magnetic resonance 460 whole heart imaging 405, 416 whole-body 3D CEMRA 396 Wilkins scoring system, mitral valve morphology 267 475 ... stenosis 25 2 Dynamic LV outflow tract obstruction 25 4 The mitral valve 25 6 Mitral regurgitation 25 8 Mitral stenosis 26 4 The pulmonary valve 26 8 Pulmonary regurgitation 27 0 Pulmonary stenosis 27 4 Right... outflow tract obstruction 27 8 Supravalvar pulmonary stenosis 27 8 The tricuspid valve 28 0 Tricuspid regurgitation 28 2 Tricuspid stenosis 28 6 Imaging prosthetic valves 28 8 23 5 23 6 CHAPTER 10 Valve disease... malignancy 23 3 This page intentionally left blank Chapter 10 Valve disease CMR in valvular heart disease 23 6 The aortic valve 23 8 Aortic regurgitation 24 0 Aortic stenosis 24 4 Sub-aortic stenosis 25 0

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