Differential Diagnosis of Thick Myocardium according to Histologic Features Revealed by Multiparametric Cardiac Magnetic Resonance Imaging

Figures

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  Fig. 1. CMR findings of normal LV myocardium based on histologic features. A. A schematic illustration of representative histological findings of a normal heart shows that cardiomyocytes striate in a well-ordered arrangement, and extracellular connective tissue supports cardiomyocytes as a fibrous skeleton. The nuclei are centrally located and oval or fusiform in shape. B. The thickness of the LV myocardium is normally between 6 and 11 mm on cine images of the end-diastolic phase. C. The LV myocardium is homogeneously nulled and reveals a dark signal intensity on the LGE image. D, E. On native T1 maps, the LV myocardium generally exhibits homogeneous T1 values between 1174 and 1228 ms on 3T MRI. F. After contrast media injection, the myocardium reveals homogenous post-T1 values that are greater than those in the LV cavity. G. On T2 maps, normal myocardium usually demonstrates T2 values between 35 and 40 ms on 3T MRI. H, I. The ECV fraction of the LV is approximately 25%. CMR = cardiac magnetic resonance, ECV = extracellular volume, LGE = late gadolinium enhancement, LV = left ventricular

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  Fig. 2. CMR findings of HCM based on histologic features. A. A schematic illustration of representative histological findings of HCM includes cardiomyocyte hypertrophy with a disorganized arrangement of fibers and interstitial fibrosis. Variations in muscle fiber thickness and enlarged and hyperchromatic nuclei are characteristic features. B. On short-axis cine images of the end-diastolic phase, the LV wall is thickened, measuring 18 mm. C. LGE imaging reveals patchy hyperenhancement in a thickened myocardium, which correlates histologically with regions of fibrosis. D. The native T1 map shows heterogeneous native T1 values of the myocardium, measuring up to 1320 ms on 3T MRI. E. After contrast media injection, the myocardium showed patchy areas with decreased post-T1 values. F. The T2 map shows increased T2 values of thickened myocardium, measuring up to 45 ms on 3T MRI. G, H. The ECV fraction map (G) and bull’s eye diagram (H) demonstrate increased ECV of the myocardium, up to 50.6%. I. A bull’s eye polar map of the GLS measured on cine images shows decreased absolute strain values in each myocardial segment. CMR = cardiac magnetic resonance, ECV = extracellular volume, GLS = global…

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  Fig. 3. CMR findings of hypertensive heart disease based on histologic features. A. A schematic illustration of representative histological findings of hypertensive heart disease indicates that cardiomyocytes are hypertrophied with preserved parallel alignment. The intermuscular space is widened, and interstitial and perivascular fibrosis can be observed. B. On the short-axis cine image of the end-diastolic phase, the LV myocardium is concentrically thickened, measuring up to 17 mm. C. LGE image shows focal hyperenhancement at the right ventricular insertion points. D. The native T1 map shows slightly increased native T1 values of the LV septum, measuring up to 1286 ms on 3T MRI. E. On the post-contrast T1 map, the myocardium shows homogenous post-T1 values. F. The T2 map shows even T2 values. G, H. The ECV fraction map (G) and bull’s eye diagram (H) demonstrate a slightly increased ECV fraction of the myocardium, up to 32.9%. I. A bull’s eye polar map of the GLS measured on cine images shows relatively preserved LV strain values in each myocardial segment. CMR = cardiac magnetic resonance, ECV = extracellular volume, GLS = global longitudinal strain, LGE = late gadolinium enhancement,…

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  Fig. 4. CMR findings of aortic stenosis based on histologic features. A. A schematic illustration of representative histological findings in aortic stenosis shows that cardiomyocytes are thickened and nuclei are enlarged with preserved muscle fiber alignment. B. Three-chamber cine image of the systolic phase shows thickened aortic valves with artifacts in the supra-valvular area. C. The left ventricular myocardium is concentrically thickened, measuring up to 18 mm on a short-axis cine image of the end-diastolic phase. D. LGE image reveals multifocal patchy myocardial scarring. E. The native T1 map shows increased native T1 values, measuring up to 1315 ms on 3T MRI. F. On the post-contrast T1 map, the myocardium shows heterogeneous post-T1 values with multifocal patchy foci and decreased T1 values. G. The T2 map shows relatively even myocardial T2 values. H, I. The ECV fraction map (H) and bull’s eye diagram (I) demonstrate an increased ECV fraction in the myocardium. CMR = cardiac magnetic resonance, ECV = extracellular volume, LGE = late gadolinium enhancement

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  Fig. 5. CMR findings of Anderson-Fabry disease based on histologic features. A. The distinct histological feature of Fabry disease is the accumulation of intracellular lysosomal glycosphingolipids. A schematic illustration of representative histologic findings revealing hypertrophic myocytes with perinuclear and cytoplasmic vacuoles. B. On the short-axis cine image of the end-diastolic phase, the LV wall showed concentric thickening. C. LGE imaging revealed focal hyperenhancement in the lateral free wall of the basal left ventricle. D, E. The native T1 map shows heterogeneous T1 values of the myocardium, with decreased native T1 values at the basal LV septum and increased native T1 values at the lateral free wall. F. The T2 map shows slightly increased T2 values at the lateral free wall. G. After contrast media injection, the myocardium demonstrated a focal area of decreased post-T1 values in the lateral LV wall. H, I. The ECV fraction map (H) and bull’s eye diagram (I) show an increased ECV fraction at the lateral free wall, corresponding to the LGE area. CMR = cardiac magnetic resonance, ECV = extracellular volume, LGE = late gadolinium enhancement, LV = left ventricular

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  Fig. 6. CMR findings of immunoglobulin light-chain amyloidosis based on histologic features. A. A schematic illustration of representative histologic findings of cardiac amyloidosis showing interstitial deposits of amorphous material (amyloid). B. In the four-chamber cine image of the end-diastolic phase, diffuse LV and right ventricular wall thickening are observed. C. LGE image reveals diffuse circumferential LV subendocardial hyperenhancement. D, E. The native T1 map shows diffusely increased native T1 values in the myocardium. F. After contrast media injection, the myocardium demonstrates low subendocardial post-T1 values in the left ventricle. G. The T2 map shows diffusely increased T2 values in the myocardium, measuring up to 55 ms. H. The bull’s eye diagram of ECV fraction demonstrates a markedly increased ECV fraction of the myocardium, which is calculated to be up to 61.5%. I. A bull’s eye polar map of the GLS measured on cine images shows decreased ventricular strain values with relative apical sparing. CMR = cardiac magnetic resonance, ECV = extracellular volume, GLS = global longitudinal strain, LGE = late gadolinium enhancement, LV = left ventricular

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  Fig. 7. CMR findings of mitochondrial cardiomyopathy based on histologic features. A. A schematic illustration of the histological features of mitochondrial cardiomyopathy indicating myocyte hypertrophy with vacuolar changes. B. On short-axis cine image of the end-diastolic phase, the LV shows concentric wall thickening. C. LGE imaging reveals the absence of focal abnormal hyperenhancement in the LV. D-F. The T2 maps (D, E) and bull’s eye diagram (F) show diffusely increased T2 values of the myocardium, measuring up to 69.8 ms on 1.5T MRI. G. The native T1 map shows diffusely increased native T1 values of the myocardium, measuring up to 1150 ms on 1.5T MRI. H. After contrast media injection, the myocardium reveals homogeneous post-T1 values in the LV. I. The ECV fraction map shows normal LV ECV fraction. CMR = cardiac magnetic resonance, ECV = extracellular volume, LGE = late gadolinium enhancement, LV = left ventricular

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  Fig. 8. CMR findings of cardiac sarcoidosis based on histologic features. A. A schematic illustration of the histological features of sarcoidosis represents interstitial non-caseating granulomas, comprising a collection of epithelioid histiocytes and lymphocytes with multinucleated giant cells distributed along the lymphatics. B, C. On the short-axis cine image of the end-diastolic phase, basal thinning of the interventricular septum is noted (B), with epicardial or transmural enhancement on the LGE image (C). D, E. At the mid-left ventricular level, the interventricular septum shows mild thickening, measuring up to 16 mm (D), with hyperenhancement of the epicardial layer on the LGE image (E). F. The T2 map shows heterogeneously increased myocardial T2 values. G. The native T1 map shows increased native T1 values, measuring up to 1350 ms on 3T MRI. H. The post-T1 map demonstrates relatively lower post-T1 values at the epicardial layer of inferoseptal wall, corresponding to the LGE area. I. The LGE image of the basal level with fusion of 18F-labeled fluoro-2-deoxyglucose PET suggests active inflammation surrounding the regions of an established scar. CMR = cardiac magnetic resonance, LGE…