Virtual calcium removal in calcified coronary arteries with photon-counting detector CT—first in-vivo experience

PurposeTo evaluate the feasibility and accuracy of quantification of calcified coronary stenoses using virtual non-calcium (VNCa) images in coronary CT angiography (CCTA) with photon-counting detector (PCD) CT compared with quantitative coronary angiography (QCA).Materials and methodsThis retrospective, institutional-review board approved study included consecutive patients with calcified coronary artery plaques undergoing CCTA with PCD-CT and invasive coronary angiography between July and December 2022. Virtual monoenergetic images (VMI) and VNCa images were reconstructed. Diameter stenoses were quantified on VMI and VNCa images by two readers. 3D-QCA served as the standard of reference. Measurements were compared using Bland-Altman analyses, Wilcoxon tests, and intraclass correlation coefficients (ICC).ResultsThirty patients [mean age, 64 years ± 8 (standard deviation); 26 men] with 81 coronary stenoses from calcified plaques were included. Ten of the 81 stenoses (12%) had to be excluded because of erroneous plaque subtraction on VNCa images. Median diameter stenosis determined on 3D-QCA was 22% (interquartile range, 11%–35%; total range, 4%–88%). As compared with 3D-QCA, VMI overestimated diameter stenoses (mean differences −10%, p < .001, ICC: .87 and −7%, p < .001, ICC: .84 for reader 1 and 2, respectively), whereas VNCa images showed similar diameter stenoses (mean differences 0%, p = .68, ICC: .94 and 1%, p = .07, ICC: .93 for reader 1 and 2, respectively).ConclusionFirst experience in mainly minimal to moderate stenoses suggests that virtual calcium removal in CCTA with PCD-CT, when feasible, has the potential to improve the quantification of calcified stenoses

Usefulness of 3-Tesla Cardiac Magnetic Resonance to Detect Mitral Annular Disjunction in Patients With Mitral Valve Prolapse

International audienceMitral annulus disjunction (MAD) is characterized by a separation between the atrial wall mitral junction and the left ventricular (LV) free wall. Little is known regarding cardiac magnetic resonance (CMR) performance to detect MAD and its prevalence in mitral valve prolapse (MVP). Based on 89 MVP patients (63 women; mean age 64 +/- 13) referred for CMR assessment of MR, either from myxomatous mitral valve disease (MMVP) (n = 40; 45%) or fibroelastic disease (n = 49; 55%), we sought to assess the frequency of MAD and its consequences on LV morphology. Patients were classified in 2 groups according to MAD presence (MAD+) or absence (MAD-). MAD (measuring 8 +/- 4 mm) was diagnosed in 35% (31 of 89) of MVP patients, more frequently in MMVP than fibroelastic disease (60% vs 14%). MAD+ was associated with MMVP; bileafiet MVP and nonsustain ventricular tachycardia but not with the severity of MR. Diagnostic accuracy of transthoracic echocardiography for the detection of MAD was fair (65% sensitivity, 96% specificity) with CMR as reference. MAD+ showed significantly enlarged basal and mid LV diameters and enlarged mitral-annulus diameter. In patients with late gadolinium enhancement, presence of LV fibrosis at level of papillary muscle was more frequent in MAD+. After adjustment on age and MR severity, MMVP, and enlarged end-systolic mitral annulus diameter were independently associated with MAD+. In conclusion, MAD was present in about 1/3 of MVP patients, mostly in MMVP and independent of MR severity. Enlarged mitral-annulus and basal LV diameters, nonsustain ventricular tachycardia and papillary muscle fibrosis were associated with MAD presence. (C) 2019 Elsevier Inc. All rights reserved

Influence of Prolapse Volume in Mitral Valve Prolapse

International audienceMitral valve prolapse (MVP) is characterized by excessive leaflet tissue leading to a wide spectrum of mitral regurgitation (MR) ranging from trivial to severe. The prolapse volume (PV) below the prolapsing leaflets in end-systole was suspected to impact both chamber remodeling and MR grading in MVP. Based on 157 consecutive patients (45 women; mean age 62 +/- 15) referred for CMR assessment of MR, either from MVP (n = 91; 58%) or fibroelastic disease (FED) (n = 66; 42%), we sought to study (i) the interaction between PV and cardiac chamber geometry (ii) to study the impact of PV on MR quantification in MVP. Despite similar left ventricular (LV) size, PV was larger in MVP (11 +/- 9ml) than in FED (2 +/- 2ml). PV progressively increased with the severity of MR in MVP but not in FED. Despite a low regurgitant volume (32 +/- 18ml), some MVP patients with less than moderate MR exhibit significant cardiac chambers remodeling compared to 52 age and sex-matched controls. PV correlated significantly (r = 0.52) with the LV dilatation in severe MR but also in less than moderate MR. In MVP, PV>14ml was associated with a significant underestimation (Bias=-26 +/- 32ml) of regurgitant volume by PISA compared to CMR. In conclusion, in MVP, PV may play a role in left cardiac chambers remodeling, even in patients without severe MR, and in discordant grading of MR between echocardiography and CMR. (C) 2021 Elsevier Inc. All rights reserved

Usefulness of 3-Tesla cardiac magnetic resonance imaging in the assessment of aortic stenosis severity in routine clinical practice

International audienceBackground. - Recently, 1.5-Tesla cardiac magnetic resonance imaging (CMR) was reported to provide a reliable alternative to transthoracic echocardiography (TTE) for the quantification of aortic stenosis (AS) severity. Few data are available using higher magnetic field strength MRI systems in this context. Aims. - To evaluate the feasibility and reproducibility of the assessment of aortic valve area (AVA) using 3-Tesla CMR in routine clinical practice, and to assess concordance between TTE and CMR for the estimation of AS severity. Methods. - Ninety-one consecutive patients (60 men; mean age 74 +/- 10 years) with known AS documented by TTE were included prospectively in the study. Results. - All patients underwent comprehensive TTE and CMR examination, including AVA estimation using the TTE continuity equation (0.81 +/- 0.18 cm(2)), direct CMR planimetry (CMRp) (0.90 +/- 0.22 cm(2)) and CMR using Hakki's formula (CMRhk), a simplified Gorlin formula (0.70 +/- 0.19 cm(2)). Although significant agreement with TTE was found for CMRp (r=0.72) and CMRhk (r = 0.66), CMRp slightly overestimated (bias= 0.11 +/- 0.18 cm(2)) and CMRhk slightly underestimated (bias = 0.11 +/- 0.17 cm(2)) AVA compared with TTE. Inter- and intraobserver reproducibilities of CMR measurements were excellent (r= 0.72 and r= 0.74 for CMRp and r= 0.88 and r=0.92 for peak aortic velocity, respectively). Conclusion. - 3-Tesla CMR is a feasible, radiation-free, reproducible imaging modality for the estimation of severity of AS in routine practice, knowing that CMRp tends to overestimate AVA and CMRhk to underestimate AVA compared with TTE. (C) 2016 Elsevier Masson SAS. All rights reserved

First in-vivo coronary stent imaging with clinical ultra high resolution photon-counting CT

BACKGROUND: Coronary stent imaging remains limited with conventional CT. In this patient study we evaluated the quality of coronary stent imaging and determined the optimal reconstruction settings for ultra-high-resolution (UHR) coronary CT angiography (cCTA) with clinical photon-counting-detector CT (PCD-CT). METHODS: In this retrospective dual-center study, 22 patients with 36 coronary stents who underwent UHR cCTA with PCD-CT were included. Images with a slice thickness of 0.6mm and Bv40 kernel and UHR images at a slice thickness of 0.2mm with kernels of eight sharpness levels (Bv40, Bv44, Bv56, Bv60, Bv64, Bv72, Bv80, and Bv89) and adapted matrix-sizes and field-of-views were reconstructed. Image noise, contrast-to-noise-ratio (CNR), in-stent diameters, and differences of in-stent attenuation compared with adjacent segments were measured. Stent strut sharpness was quantified using data derived from line profiles. Subjective in-stent lumen visualization was rated by two blinded, independent readers. In-vitro stent diameters were taken as reference standard. RESULTS: At increasing kernel sharpness, CNR decreased, in-stent diameter increased (1.8 ​± ​0.5mm for 0.6mm/Bv40 to 2.5 ​± ​0.5mm for 0.2mm/Bv89), and stent strut sharpness increased. Differences of in-stent attenuation decreased from 0.6mm/Bv40 to 0.2 mm/Bv60-Bv80 kernels, being not different from zero for the latter kernels (p ​> ​0.05). Percentage (absolute) differences of measured to in-vitro diameters decreased from 40.1 ​± ​11.1% (1.2 ​± ​0.4mm) for 0.6mm/Bv40 to 16.6 ​± ​8% (0.5 ​± ​0.3mm) for 0.2mm/Bv89. There were no associations between stent angulation and in-stent diameter or attenuation differences (p ​> ​0.05). Qualitative scores increased from suboptimal/good for 0.6mm/Bv40 to very good/excellent for 0.2mm/Bv64 and 0.2mm/Bv72. CONCLUSION: UHR cCTA with clinical PCD-CT enables excellent in-vivo coronary stent lumen visualization

Table1_Virtual calcium removal in calcified coronary arteries with photon-counting detector CT—first in-vivo experience.docx

PurposeTo evaluate the feasibility and accuracy of quantification of calcified coronary stenoses using virtual non-calcium (VNCa) images in coronary CT angiography (CCTA) with photon-counting detector (PCD) CT compared with quantitative coronary angiography (QCA).Materials and methodsThis retrospective, institutional-review board approved study included consecutive patients with calcified coronary artery plaques undergoing CCTA with PCD-CT and invasive coronary angiography between July and December 2022. Virtual monoenergetic images (VMI) and VNCa images were reconstructed. Diameter stenoses were quantified on VMI and VNCa images by two readers. 3D-QCA served as the standard of reference. Measurements were compared using Bland-Altman analyses, Wilcoxon tests, and intraclass correlation coefficients (ICC).ResultsThirty patients [mean age, 64 years ± 8 (standard deviation); 26 men] with 81 coronary stenoses from calcified plaques were included. Ten of the 81 stenoses (12%) had to be excluded because of erroneous plaque subtraction on VNCa images. Median diameter stenosis determined on 3D-QCA was 22% (interquartile range, 11%–35%; total range, 4%–88%). As compared with 3D-QCA, VMI overestimated diameter stenoses (mean differences −10%, p ConclusionFirst experience in mainly minimal to moderate stenoses suggests that virtual calcium removal in CCTA with PCD-CT, when feasible, has the potential to improve the quantification of calcified stenoses.</p