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Purpose: To explore the potential differences in epicardial adipose tissue (EAT) volume and attenuation measurements between photon-counting detector (PCD) and energy-integrating detector (EID)-CT systems., Methods: Fifty patients (mean age 69 ± 8 years, 41 male [82 %]) were prospectively enrolled for a research coronary CT angiography (CCTA) on a PCD-CT within 30 days after clinical EID-based CCTA. EID-CT acquisitions were reconstructed using a Bv40 kernel at 0.6 mm slice thickness. The PCD-CT acquisition was reconstructed at a down-sampled resolution (0.6 mm, Bv40; [PCD-DS]) and at ultra-high resolutions (PCD-UHR) with a 0.2 mm slice thickness and Bv40, Bv48, and Bv64 kernels. EAT segmentation was performed semi-automatically at about 1 cm intervals and interpolated to cover the whole epicardium within a threshold of -190 to -30 HU. A subgroup analysis was performed based on quartile groups created from EID-CT data and PCD-UHR Bv48 data. Differences were measured using repeated-measures ANOVA and the Friedman test. Correlations were tested using Pearson's and Spearman's rho, and agreement using Bland-Altman plots., Results: EAT volumes significantly differed between some reconstructions (e.g., Eid-Ct: 138 ml [IQR 100, 188]; PCD-DS: 147 ml [110, 206]; P<0.001). Overall, correlations between PCD-UHR and EID-CT EAT volumes were excellent, e.g. PCD-UHR Bv48 : r: 0.976 (95 % CI: 0.958, 0.987); P<0.001; with good agreement (mean bias: -9.5 ml; limits of agreement [LoA]: -40.6, 21.6). On the other hand, correlations regarding EAT attenuation was moderate, e.g. PCD-UHR BV48 : r: 0.655 (95 % CI: 0.461, 0.790); P<0.001; mean bias: 6.5 HU; LoA: -2.0, 15.0., Conclusion: EAT attenuation and volume measurements demonstrated different absolute values between PCD-UHR, PCD-DS as well as EID-CT reconstructions, but showed similar tendencies on an intra-individual level. New protocols and threshold ranges need to be developed to allow comparison between PCD-CT and EID-CT data., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: UJS receives institutional research support and / or personal fees from Bayer, Bracco, Elucid Bioimaging, Guerbet, HeartFlow, Keya Medical, and Siemens. AVS receives institutional research support and / or personal fees from Elucid Bioimaging and Siemens. TE received a speaker fee and travel support from Siemens, institutional research support by Siemens and is a consultant at Circle CVI. JOD is an employee of Siemens., (Copyright © 2024. Published by Elsevier B.V.)

Purpose: To compare standard breath-hold (BH) cine imaging to a radial pseudo-golden-angle free-breathing (FB) technique in congenital heart disease (CHD)., Methods: In this prospective study, short-axis and 4-chamber BH and FB cardiac MRI sequences of 25 participants with CHD acquired at 1.5 Tesla, were quantitatively compared regarding ventricular volumes, function, interventricular septum thickness (IVSD), apparent signal to noise ratio (aSNR), and estimated contrast to noise ratio (eCNR). For qualitative comparison, three image quality criteria (contrast, endocardial edge definition, and artefacts) were rated on a 5-point Likert scale (5: excellent, 1: non-diagnostic). Paired t-Test was used for group comparisons, Bland-Altman analysis for agreement between techniques. Inter-reader agreement was compared using intraclass correlation coefficient., Results: IVSD (BH 7.4 ± 2.1 mm vs FB 7.4 ± 1.9 mm, p =.71), biventricular ejection fraction (left ventricle [LV]: 56.4 ± 10.8% vs 56.1 ± 9.3%, p =.83; right ventricle [RV]: 49.5 ± 8.6% vs 49.7 ± 10.1%, p =.83), and biventricular end diastolic volume (LV: 176.3 ± 63.9 ml vs 173.9 ± 64.9 ml, p =.90; RV: 185.4 ± 63.8 ml vs 189.6 ± 66.6 ml, p =.34) were comparable. Mean measurement time for FB short-axis sequences was 8.1 ± 1.3 compared to 4.4 ± 1.3 min for BH (p <.001). Subjective image quality between sequences was deemed comparable, (4.6 ± 0.6 vs 4.5 ± 0.6, p =.26, for 4-chamber views) with a significant difference regarding short-axis views (4.9 ± 0.3 vs 4.5 ± 0.6, p =.008). aSNR was similar (BH 25.8 ± 11.2 vs FB 22.2 ± 9.5, p =.24), while eCNR was higher for BH (89.1 ± 36.1 vs 68.5 ± 32.1, p =.03)., Conclusion: FB sequences yielded comparable results to BH regarding image quality, biventricular volumetry, and function, though measurement times were longer. The FB sequence described might be clinically valuable when BHs are insufficiently performed., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Purpose: Using a three-dimensional ECG- and respiratory navigator gated magnetization prepared mDixon-sequence (3D-Dixon) we quantified epi- and pericardial fat volumes (EFV, PFV) in hypertensive men compared to a healthy control group and related the amount of fat volumes in hypertensive men to the presence of coronary artery disease (CAD) and myocardial infarction (MI)., Materials and Methods: 55 hypertensive men (mean age 63.02±10.73years [y]) with MI (n=22; mean age 61.55±10.50y) and without MI (n=33; mean age 63.17±10.93y), and a group of ten healthy men (mean age 59.00±8.41y) underwent a comprehensive cardiomagnetic resonance (CMR) examination on a 1.5T MR system (Ingenia, Philips). Hypertensive men without MI consisted of patients with CAD (n=15) and without CAD (n=18). EFV and PFV were assessed using 3D-Dixon. Fat only images were reconstructed online at the scanner, and the segmentation of fat volumes was performed based on fat fraction maps. EFV and PFV were normalized to the body surface area (ml/m(2))., Results: Mean EFV and PFV in all hypertensive men (81.8±33.90 and 194.86±83.51) as well as in hypertensive men with no CAD (74.53±26.40 and 174.60±65.70) were significantly higher than in the healthy controls (52.98±19.81 and 115.50±53.57; P<0.05, each). EFV and PFV in hypertensive men with MI (94.14±43.16 and 224.26±100.79) were significantly higher than in hypertensive men with no MI (73.57±23.27 and 175.26±63.07; P<0.05, each). There were no significant differences in age, BMI or heart rate between the groups., Conclusion: 3D-Dixon measurements revealed significantly higher epi- and pericardial fat volumes in hypertensive men with myocardial infarction compared to hypertensive men without MI. This finding underscores the role of cardiac fatty tissue as a proinflammatory and metabolically active organ. Non-invasive CMR-based whole volume measurement of epi- and pericardial fat may play a relevant future role in cardiovascular risk stratification and disease management., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)