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Accurate chamber volumetry from gated, non-contrast cardiac CT (NCCT) scans can be useful for potential screening of heart failure. To validate a new, fully automated, AI-based method for cardiac volume and myocardial mass quantification from NCCT scans compared to contrasted CT Angiography (CCTA). Of a retrospectively collected cohort of 1051 consecutive patients, 420 patients had both NCCT and CCTA scans at mid-diastolic phase, excluding patients with cardiac devices. Ground truth values were obtained from the CCTA scans. The NCCT volume computation shows good agreement with ground truth values. Volume differences [95% CI ] and correlation coefficients were: -9.6 [–45; 26] mL, r ​= ​0.98 for LV Total, −5.4 [–24; 13] mL, r ​= ​0.95 for LA, −8.7 [-45; 28] mL, r ​= ​0.94 for RV, −5.2 [–27; 17] mL, r ​= ​0.92 for RA, −3.2 [–42; 36] mL, r ​= ​0.91 for LV blood pool, and −6.7 [–39; 26] g, r ​= ​0.94 for LV wall mass, respectively. Mean relative volume errors of less than 7% were obtained for all chambers. Fully automated assessment of chamber volumes from NCCT scans is feasible and correlates well with volumes obtained from contrast study. Cardiac chamber volume is known to be an excellent predictor of future heart failure events. According to recent guidelines, gated, non-contrast cardiac CT (NCCT) is recommended for CAD screening in asymptomatic individuals at low to intermediate risk. We validated a novel, fully automated, AI based method for cardiac chamber volume and myocardial mass quantification from gated NCCT scans used for coronary calcium scoring. NCCT based volume quantification shows excellent agreement with the volumes obtained from CCTA scans in the same patient. Thus, volume assessment from NCCT scans acquired for calcium scoring appears feasible for potential screening. [ABSTRACT FROM AUTHOR]

Abstract Background The purpose of the study was to compare the accuracy and evaluation time of quantifying left ventricular (LV), left atrial (LA) volume and LV mass using short axis (SAX) and long axis (LAX) methods when using cardiovascular magnetic resonance (CMR). Materials and methods We studied 12 explanted canine hearts and 46 patients referred for CMR (29 male, age 47 ± 18 years) in a clinical 1.5 T CMR system, using standard cine sequences. In standard short axis stacks of various slice thickness values in dogs and 8 mm slice thickness (gap 2 mm) in patients, we measured LV volumes using reference slices in a perpendicular, long axis orientation using certified software. Volumes and mass were also measured in six radial long axis (LAX) views. LV parameters were also assessed for intra- and inter-observer variability. In 24 patients, we also analyzed reproducibility and evaluation time of two very experienced (> 10 years of CMR reading) readers for SAX and LAX. Results In the explanted dog hearts, there was excellent agreement between ex vivo data and LV mass and volume data as measured by all methods for both, LAX (r2 = 0.98) and SAX (r2 = 0.88 to 0.98). LA volumes, however, were underestimated by 13% using the LAX views. In patients, there was a good correlation between all three assessed methods (r2 ≥ 0.95 for all). In experienced clinical readers, left-ventricular volumes and ejection fraction as measured in LAX views showed a better inter-observer reproducibility and a 27% shorter evaluation time. Conclusion When compared to an ex vivo standard, both, short axis and long axis techniques are highly accurate for the quantification of left ventricular volumes and mass. In clinical settings, however, the long axis approach may be more reproducible and more time-efficient. Therefore, the rotational long axis approach is a viable alternative for the clinical assessment of cardiac volumes, function and mass.

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Prodigious efforts and landmark discoveries have led toward significant advances in our understanding of atherosclerosis. Despite significant efforts, atherosclerosis continues globally to be a leading cause of mortality and reduced quality of life. With surges in the prevalence of obesity and diabetes, atherosclerosis is expected to have an even more pronounced impact upon the global burden of disease. It is imperative to develop strategies for the early detection of disease. Positron emission tomography (PET) imaging utilizing [F]fluorodeoxyglucose (FDG) may provide a non-invasive means of characterizing inflammatory activity within atherosclerotic plaque, thus serving as a surrogate biomarker for detecting vulnerable plaque. The aim of this review is to explore the rationale for performing FDG imaging, provide an overview into the mechanism of action, and summarize findings from the early application of FDG PET imaging in the clinical setting to evaluate vascular disease. Alternative imaging biomarkers and approaches are briefly discussed. [ABSTRACT FROM AUTHOR]

Objectives: This study was designed to determine whether imaging myocardial edema would identify acute myocardial ischemia before irreversible injury takes place. Background: Early identification of acute myocardial ischemia is a diagnostic challenge. Methods: We studied 15 dogs with serial T2-weighted and cine imaging at baseline, during transient coronary occlusion of up to 35 min, and after reperfusion in a 1.5-T magnetic resonance imaging system. Late gadolinium enhancement and troponin measurements were used to assess for the presence of irreversible injury. Myocardial water content was measured to assess myocardial edema. Results: We consistently observed a transmural area of high T2 signal intensity matching areas with new onset regional akinesia 28 ± 4 min after experimental coronary artery occlusion. At this time, the contrast-to-noise ratio between the ischemic and remote myocardium had significantly increased from 1.0 ± 2.0 to 12.8 ± 9.6 (p < 0.003), which further increased after reperfusion to 15.8 ± 10.3 (p < 0.004 compared with baseline). Neither myocardial late gadolinium enhancement nor troponin elevation were noted at this time window. Myocardial water content of the ischemic segments was consistently higher (68.9 ± 2% vs. 67.0 ± 2%; p < 0.004) than in remote segments and the difference correlated significantly to the contrast-to-noise ratio in T2 images (p < 0.04). Conclusions: We provide the first evidence that T2-weighted cardiovascular magnetic resonance imaging of edema detects acute ischemic myocyte injury before the onset of irreversible injury. T2-weighted cardiovascular magnetic resonance imaging may serve as a very useful diagnostic marker in clinical settings such as unstable angina or evolving infarction. [Copyright &y& Elsevier]

The article presents an abstract on a paper titled "Evidence of an Increased Incidence of Myocardial Inflammation Associated With Reduced Ventricular Function in Clinically Suspected Idiopathic Dilated Cardiomyopathy: A Cardiovascular Magnetic Resonance Study," presented at the 2011 Society for Cardiovascular Magnetic Resonance (CMR)/Euro CMR Joint Scientific Sessions held in France.

An abstract of the paper "Development of Myocardial Edema Following Acute Bouts of Intense Physical Exertion in Healthy Active Men: A Cardiovascular Magnetic Resonance (CMR) Study," by Myra S. Cocker and colleagues is presented.

An abstract of the paper "Evaluation of papillary myocardial infarction: incremental value of a short time inversion vs standard late enhancement imaging," by Annachiara Aldrovandi and colleagues, from the 2011 SCMR/Euro CMR Joint Scientific Sessions, held in Nice, France, from February 3-6, 2011, is presented.

Purpose To investigate the ability of kilovolt-independent (hereafter, kV-independent) and tin filter spectral shaping to accurately quantify the coronary artery calcium score (CACS) and radiation dose reductions compared with the standard 120-kV CT protocol. Materials and Methods This prospective, blinded reader study included 201 participants (mean age, 60 years ± 9.8 [SD]; 119 female, 82 male) who underwent standard 120-kV CT and additional kV-independent and tin filter research CT scans from October 2020 to July 2021. Scans were reconstructed using a Qr36f kernel for standard scans and an Sa36f kernel for research scans simulating artificial 120-kV images. CACS, risk categorization, and radiation doses were compared by analyzing data with analysis of variance, Kruskal-Wallis test, Mann-Whitney test, Bland-Altman analysis, Pearson correlations, and κ analysis for agreement. Results There was no evidence of differences in CACS across standard 120-kV, kV-independent, and tin filter scans, with median CACS values of 1 (IQR, 0-48), 0.6 (IQR, 0-58), and 0 (IQR, 0-51), respectively ( P = .85). Compared with standard 120-kV scans, kV-independent and tin filter scans showed excellent correlation in CACS values ( r = 0.993 and r = 0.999, respectively), with high agreement in CACS risk categorization (κ = 0.95 and κ = 0.93, respectively). Standard 120-kV scans had a mean radiation dose of 2.09 mSv ± 0.84, while kV-independent and tin filter scans reduced it to 1.21 mSv ± 0.85 and 0.26 mSv ± 0.11, cutting doses by 42% and 87%, respectively ( P < .001). Conclusion The kV-independent and tin filter research CT acquisition techniques showed excellent agreement and high accuracy in CACS estimation compared with standard 120-kV scans, with large reductions in radiation dose. Keywords: CT, Cardiac, Coronary Arteries, Radiation Safety, Coronary Artery Calcium Score, Radiation Dose Reduction, Low-Dose CT Scan, Tin Filter, kV-Independent Supplemental material is available for this article. © RSNA, 2024.

Background: Advances in CT and machine learning have enabled on-site non-invasive assessment of fractional flow reserve (FFR CT )., Purpose: To assess the interoperator and intraoperator variability of coronary CT angiography-derived FFR CT using a machine learning-based postprocessing prototype., Materials and Methods: We included 60 symptomatic patients who underwent coronary CT angiography. FFR CT was calculated by two independent operators after training using a machine learning-based on-site prototype. FFR CT was measured 1 cm distal to the coronary plaque or in the middle of the segments if no coronary lesions were present. Intraclass correlation coefficient (ICC) and Bland-Altman analysis were used to evaluate interoperator variability effect in FFR CT estimates. Sensitivity analysis was done by cardiac risk factors, degree of stenosis and image quality., Results: A total of 535 coronary segments in 60 patients were assessed. The overall ICC was 0.986 per patient (95% CI 0.977 to 0.992) and 0.972 per segment (95% CI 0.967 to 0.977). The absolute mean difference in FFR CT estimates was 0.012 per patient (95% CI for limits of agreement: -0.035 to 0.039) and 0.02 per segment (95% CI for limits of agreement: -0.077 to 0.080). Tight limits of agreement were seen on Bland-Altman analysis. Distal segments had greater variability compared with proximal/mid segments (absolute mean difference 0.011 vs 0.025, p<0.001). Results were similar on sensitivity analysis., Conclusion: A high degree of interoperator and intraoperator reproducibility can be achieved by on-site machine learning-based FFR CT assessment. Future research is required to evaluate the physiological relevance and prognostic value of FFR CT ., Competing Interests: Competing interests: MHA-M receives research support from Siemens. CS, MC and JCRG are employed by Siemens., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Aims: To evaluate the practical use of the single slice measurement of epicardial adipose tissue (EAT) at the level of the left main coronary artery (EATLM) in predicting the presence of obstructive coronary artery disease (CAD)., Methods and Results: Quantification of EATTotal and EATLM was performed on non-contrast CT scans of consecutive patients (without history of revascularization, cardiac transplantation, device implantation, and congenital heart disease) who underwent coronary artery calcium (CAC) scoring and computed tomographic coronary angiography (CTA) between May 2011 and July 2011. One hundred and ninety-two patients were evaluated, of which 47 had obstructive CAD (>50% stenosis). EATLM (3.8 ± 2.2 cm(3)) and EATTotal (126.2 ± 56.3 cm(3)) are highly correlated (r = 0.89, P < 0.001). Multivariate analysis revealed that both EATLM (OR: 1.204 per 1 cm(3), 95% CI: 1.028-1.411, P = 0.021) and EATTotal (OR: 1.007 per 10 cm(3), 95% CI: 1.000-1.013, P = 0.038) are associated with obstructive CAD. However, when the CAC score was added to multivariate analysis, both failed to show statistical significance. (EATTotal, OR 1.004 per 1 cm(3), 95% CI: 0.996-1.011, P = 0.328 and EATLM, OR: 1.136 per 10 cm(3), 95% CI: 0.948-1.362) ROC curve analysis revealed that both EATTotal and EATLM are of incremental value in detecting CAD, when compared with clinical risk scores (NCEP plus EATTotal plus BMI and NCEP plus EATLM plus BMI vs. NCEP alone; AUC 0.7090, P = 0.009 and 0.7167, P = 0.003 vs. 0.6069, respectively)., Conclusion: Measuring epicardial adipose tissue on a single slice at the level of the left main coronary artery may serve as an indirect measure of total epicardial adipose tissue burden. EATLM and EATTotal are independently associated with obstructive coronary artery disease and are incremental to traditional risk factors for predicting its presence.

Aims: Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging can detect myocardial scar in patients with myocardial infarction. The detection of papillary muscle infarction (PMI) may be difficult due to the bright blood signal. The aim of our study was to evaluate the incremental value of LGE CMR imaging using an inversion recovery (IR)-GRE with a short-inversion time (TI) over standard LGE imaging in identifying PMI., Methods and Results: Fifty-six patients with myocardial infarction were studied using a standard IR-GRE LGE sequence with an adjusted TI to null the signal intensity of normal myocardium and with a 3D IR-GRE with a short TI (<180 ms). Signal-to-noise and contrast-to-noise ratios (CNR) and the frequency of PMI were determined. Image quality and infarction sharpness were evaluated. The short-TI LGE sequence detected a higher number of PMI compared with standard LGE sequence (19/54 vs. 15/54) with an increased sharpness of PMI (84.2 vs. 53.3%). The CNR was higher between infarcted myocardium and blood (77.9 ± 60 vs. 19.3 ± 16, P < 0.001) and between PMI and blood (69.4 ± 51 vs. 39.4 ± 26, respectively, P = 0.0157)., Conclusions: Our data indicate that in patients with myocardial infarction, LGE CMR imaging using a short TI may be more sensitive than standard LGE imaging for the detection of PMI.

Nuclear imaging, predominantly with single-photon emission tomography, has established and demonstrated value for the assessment of cardiovascular disease (CVD). Formerly, the clinical application of positron emission tomography (PET) was precluded by methodological complexity, high operating costs and lack of widespread availability. However, as PET and radiotracer development technologies have improved and continue to do so, PET is expected to become a mainstay diagnostic cardiovascular imaging modality. Not only is PET imaging of great importance for routine clinical decision-making and diagnosing CVD, it is also gaining prominence in fundamental and translational research models. The scope of this review is to summarize the state-of-the-art advances in PET imaging methodology, clinical utility and potential future application.

Introduction: With more intensive medical therapy, the risk of stroke in patients with asymptomatic carotid stenosis (ACS) is now below the risk of carotid endarterectomy or stenting (intervention); ∼ 90% of patients would be better with only medical therapy. It is important, therefore, to have methods to identify the ∼ 10% of patients who stand to benefit from intervention., Areas Covered: We review the evidence that the risk of asymptomatic stenosis is now below the risk of intervention, and evidence for several approaches to identifying high-risk ACS: transcranial Doppler embolus detection, echolucency and neovascularity on ultrasound, ulceration on three-dimensional ultrasound, plaque composition on magnetic resonance imaging (MRI), plaque inflammation on positron emission tomography and assessment of cerebral blood flow reserve., Expert Opinion: Carotid endarterectomy or stenting should be performed only in patients with ACS if they have microemboli on transcranial Doppler, three or more ulcers detected on three-dimensional ultrasound or other features of unstable plaque such as plaque echolucency on ultrasound, intraplaque hemorrhage detected on MRI, inflamed plaques detected on PET/CT or reduced cerebral blood flow reserve. Most patients with ACS (∼ 90%) would be better off with intensive medical therapy than with intervention.