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The 2022 AHA/ACC Guidelines for the Diagnosis and Management of Aortic Disease introduced important updates for managing thoracic aorta aortic disease (TAD). In particular, the Guidelines underscore multimodality imaging's role in diagnosis, risk assessment, and monitoring of patients with TAD. This commentary aims to distill key imaging aspects from the Guidelines to provide a concise reference for the cardiovascular imaging community. Primary areas of focus include: (1) The importance of imagers in the multidisciplinary TAD care team, (2) Appropriate imaging techniques along with their strengths and weaknesses, (3) Aortic measurement methods and how aortic size and growth should contribute to TAD risk assessment, (4) Imaging evaluation of acute aortic syndrome. We have also highlighted several areas of ongoing uncertainty and confusion, specifically related to aortic measurement techniques and descriptive terminology. Finally, a perspective on the future of TAD imaging is discussed with a focus on advanced imaging tools and techniques as well as the potential role of artificial intelligence. [ABSTRACT FROM AUTHOR]

The article discusses the need for standardized medical terminology in cardiac computed tomography (CT). The Society of Cardiovascular Computed Tomography (SCCT) published initial guidelines in 2011, and these guidelines were recently updated in 2023. The updated guidelines provide concise tables outlining recommended terms, definitions, and terms that are not recommended. The tables cover various categories such as equipment and examination procedures, contrast injection and data acquisition, image reconstruction and analysis, image interpretation and analysis, and multi-energy technology. The article acknowledges the thoroughness of the document but highlights potential challenges, such as limited explanation for the use of RADLEX terms and the exclusion of certain categories. Overall, the standardized terminology will improve communication and minimize confusion in clinical practice and research. [Extracted from the article]

Objectives: Time-resolved, 2D-phase-contrast MRI (2D-CINE-PC-MRI) enables in vivo blood flow analysis. However, accurate vessel contour delineation (VCD) is required to achieve reliable results. We sought to evaluate manual analysis (MA) compared to the performance of a deep learning (DL) application for fully-automated VCD and flow quantification and corrected semi-automated analysis (corSAA). Methods: We included 97 consecutive patients (age = 52.9 ± 16 years, 41 female) with 2D-CINE-PC-MRI imaging on 1.5T MRI systems at sinotubular junction (STJ), and 28/97 also received 2D-CINE-PC at main pulmonary artery (PA). A cardiovascular radiologist performed MA (reference) and corSAA (built-in tool) in commercial software for all cardiac time frames (median: 20, total contours per analysis: 2358 STJ, 680 PA). DL-analysis automatically performed VCD, followed by net flow (NF) and peak velocity (PV) quantification. Contours were compared using Dice similarity coefficients (DSC). Discrepant cases (> ± 10 mL or > ± 10 cm/s) were reviewed in detail. Results: DL was successfully applied to 97% (121/125) of the 2D-CINE-PC-MRI series (STJ: 95/97, 98%, PA: 26/28, 93%). Compared to MA, mean DSC were 0.91 ± 0.02 (DL), 0.94 ± 0.02 (corSAA) at STJ, and 0.85 ± 0.08 (DL), 0.93 ± 0.02 (corSAA) at PA; this indicated good to excellent DL-performance. Flow quantification revealed similar NF at STJ (p = 0.48) and PA (p > 0.05) between methods while PV assessment was significantly different (STJ: p < 0.001, PA: p = 0.04). A detailed review showed noisy voxels in MA and corSAA impacted PV results. Overall, DL analysis compared to human assessments was accurate in 113/121 (93.4%) cases. Conclusions: Fully-automated DL-analysis of 2D-CINE-PC-MRI provided flow quantification at STJ and PA at expert level in > 93% of cases with results being available instantaneously. Key Points: • Deep learning performed flow quantification on clinical 2D-CINE-PC series at the sinotubular junction and pulmonary artery at the expert level in > 93% of cases. • Location detection and contouring of the vessel boundaries were performed fully-automatic with results being available instantaneously compared to human assessments which approximately takes three minutes per location. • The evaluated tool indicates usability in daily practice. [ABSTRACT FROM AUTHOR]

Background: Large vessel vasculitis (LVV) can be characterized based on symptom severity, and this characterization helps clinicians decide upon treatment approach. Our aim was to compare the imaging findings of combined modality positron emission tomography/magnetic resonance (PET/MR) and inflammatory markers between severe and non-severe LVV. A retrospective query was performed to identify all patients with LVV who underwent PET/MR at our institution between January 2015 and January 2021. Results: Eleven patients (nine females; age 62.2 ± 16.4 years) underwent 15 PET/MR scans. Positivity was defined by findings indicative of active LVV on each modality: PET positive if vessel metabolic activity > liver metabolic activity; MR positive if wall thickening or contrast enhancement. When positive PET or positive MR findings were considered a positive scan, LVV patients with severe disease (n = 9 scans) showed a higher number of positive scans (n = 9) compared to the number of positive scans in non-severe patients (n = 3) (p < 0.05). The sensitivity and specificity for the detection of severe LVV were 1.00 and 0.50, respectively. When only the presence of both positive PET and positive MR findings were considered a positive scan, inflammatory marker levels were not significantly different between severe and non-severe LVV groups (severe: erythrocyte sedimentation rate (ESR) = 9.8 ± 10.6 mm/h; C-reactive protein (CRP) = 0.6 ± 0.4 mg/dL) (non-severe: ESR = 14.3 ± 22.4 mm/h; CRP = 0.5 ± 0.6 mg/dL). Blood- and liver-normalized maximum standardized uptake values were not significantly different between severe and non-severe patients (1.4 ± 0.3 vs 1.5 ± 0.4; 1.1 ± 0.4 vs 1.0 ± 0.3, respectively). Conclusions: Because of the differences observed, PET/MR appears to be better suited to facilitate the characterization of LVV as severe or non-severe compared to inflammatory marker measurements and quantitative measurements of metabolic activity. Qualitative assessment of PET and MR positivity by 18F-fluorodeoxyglucose PET/MR may be able to supplement clinical symptoms-based LVV classification decisions and may be helpful when clinical symptoms overlap with other disease processes. [ABSTRACT FROM AUTHOR]

To noninvasively assess left atrial (LA) kinetic energy (KE) in hypertrophic cardiomyopathy (HCM) patients using 4D flow MRI and evaluate coupling associations with mitral regurgitation (MR) and left ventricular outflow tract (LVOT) obstruction. Twenty-nine retrospectively identified patients with HCM underwent 4D flow MRI. MRI-estimated peak LVOT pressure gradient (∆PMRI) was used to classify patients into non-obstructive and obstructive HCM. Time-resolved volumetric LA kinetic energy (KELA) was computed throughout systole. Average systolic (KELA-avg) and peak systolic (KELA-peak) KELA were compared between non-obstructive and obstructive HCM groups, and associations to MR severity and LVOT ∆PMRI were tested.The study included 15 patients with non-obstructive HCM (58.6 [45.9, 65.2] years, 7 females) and 14 patients with obstructive HCM (51.9 [47.6, 62.6] years, 6 females). Obstructive HCM patients demonstrated significantly elevated instantaneous KELA over all systolic time-points compared to non-obstructive HCM (P < 0.05). Obstructive HCM patients also demonstrated higher KELA-avg (14.8 [10.6, 20.4] J/m3 vs. 33.4 [23.9, 61.3] J/m3, P < 0.001) and KELA-peak (22.1 [15.9, 28.7] J/m3 vs. 57.2 [44.5, 121.4] J/m3, P < 0.001) than non-obstructive HCM. MR severity was significantly correlated with KELA-avg (rho = 0.81, P < 0.001) and KELA-peak (rho = 0.79, P < 0.001). LVOT ∆PMRI was strongly correlated with KELA metrics in obstructive HCM (KELA-avg: rho = 0.86, P < 0.001; KELA-peak: rho = 0.85, P < 0.001).In HCM patients, left atrial kinetic energy, by 4D flow MRI, is associated with MR severity and the degree of LVOT obstruction. [ABSTRACT FROM AUTHOR]

Objective: The 2019 Coronavirus (COVID-19) results in a wide range of clinical severity and there remains a need for prognostic tools which identify patients at risk of rapid deterioration and who require critical care. Chest radiography (CXR) is routinely obtained at admission of COVID-19 patients. However, little is known regarding correlates between CXR severity and time to intubation. We hypothesize that the degree of opacification on CXR at time of admission independently predicts need and time to intubation. Methods: In this retrospective cohort study, we reviewed COVID-19 patients who were admitted to an urban medical center during March 2020 that had a CXR performed on the day of admission. CXRs were divided into 12 lung zones and were assessed by two blinded thoracic radiologists. A COVID-19 opacification rating score (CORS) was generated by assigning one point for each lung zone in which an opacity was observed. Underlying comorbidities were abstracted and assessed for association. Results: One hundred forty patients were included in this study and 47 (34%) patients required intubation during the admission. Patients with CORS ≥ 6 demonstrated significantly higher rates of early intubation within 48 h of admission and during the hospital stay (ORs 24 h, 19.8, p < 0.001; 48 h, 28.1, p < 0.001; intubation during hospital stay, 6.1, p < 0.0001). There was no significant correlation between CORS ≥ 6 and age, sex, BMI, or any underlying cardiac or pulmonary comorbidities. Conclusions: CORS ≥ 6 at the time of admission predicts need for intubation, with significant increases in intubation at 24 and 48 h, independent of comorbidities. Key Points: • Chest radiography at the time of admission independently predicts time to intubation within 48 h and during the hospital stay in COVID-19 patients. • More opacities on chest radiography are associated with several fold increases in early mechanical ventilation among COVID-19 patients. • Chest radiography is useful in identifying COVID-19 patients whom may rapidly deteriorate and help inform clinical management as well as hospital bed and ventilation allocation. [ABSTRACT FROM AUTHOR]

Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy with a wide spectrum of clinical manifestations. Patients can be asymptomatic or suffer major adverse events including sudden cardiac death, ventricular arrhythmias, and heart failure. Identification of individuals with HCM who are at risk for these complications remains challenging. While echocardiography remains the mainstay of diagnostic evaluation, cardiac magnetic resonance imaging (CMR) is an important adjunctive diagnostic modality with emerging applications for risk-stratification of adverse events in the HCM population. Although not included in current guidelines for HCM management, there is increasing evidence to support the use of CMR for routine prognostic assessment of HCM patients. In this review we discuss the use of CMR techniques, including late gadolinium enhancement, T1 mapping, and quantification of extracellular volume fraction, for the risk stratification of three major adverse events in HCM: sudden cardiac death, ventricular arrhythmias, and congestive heart failure. [ABSTRACT FROM AUTHOR]

Objectives: Recent studies with lung MRI (MRI) have shown high sensitivity (Sn) and specificity (Sp) for lung nodule detection and characterization relative to low-dose CT (LDCT). Using this background data, we sought to compare the potential screening performance of MRI vs. LDCT using a Markov model of lung cancer screening.Methods: We created a Markov cohort model of lung cancer screening which incorporated lung cancer incidence, progression, and mortality based on gender, age, and smoking burden. Sensitivity (Sn) and Sp for LDCT were taken from the MISCAN Lung Microsimulation and Sn/Sp for MRI was estimated from a published substudy of the German Lung Cancer Screening and Intervention Trial. Screening, work-up, and treatment costs were estimated from published data. Screening with MRI and LDCT was simulated for a cohort of male and female smokers (2 packs per day; 36 pack/years of smoking history) starting at age 60. We calculated the screening performance and cost-effectiveness of MRI screening and performed a sensitivity analysis on MRI Sn/Sp and cost.Results: There was no difference in life expectancy between MRI and LDCT screening (males 13.28 vs. 13.29 life-years; females 14.22 vs. 14.22 life-years). MRI had a favorable cost-effectiveness ratio of $258,169 in men and $403,888 in women driven by fewer false-positive screens. On sensitivity analysis, MRI remained cost effective at screening costs < $396 dollars and Sp > 81%.Conclusions: In this Markov model of lung cancer screening, MRI has a near-equivalent life expectancy benefit and has superior cost-effectiveness relative to LDCT.Key Points: • In this Markov model of lung cancer screening, there is no difference in mortality between yearly screening with MRI and low-dose CT. • Compared to low-dose CT, screening with MRI led to a reduction in false-positive studies from 26 to 2.8% in men and 26 to 2.6% in women. • Due to similar life-expectancy and reduced false-positive rate, we found a favorable cost-effectiveness ratio of $258,169 in men and $403,888 in women of MRI relative to low-dose CT. [ABSTRACT FROM AUTHOR]

Background: Children with bicuspid aortic valve (BAV) are at risk for serious complications including aortic valve stenosis and aortic rupture. Most studies investigating biomarkers predictive of BAV complications are focused on adults.Objective: To investigate whether hemodynamic parameters change over time in children and young adults with BAV by comparing baseline and follow-up four-dimensional (4-D) flow MRI examinations.Materials and Methods: We retrospectively included 19 children and young adults with BAV who had serial 4-D flow MRI exams (mean difference in scan dates 1.8±1.0 [range, 0.6-3.4 years]). We compared aortic peak blood flow velocity, three-dimensional (3-D) wall shear stress, aortic root and ascending aortic (AAo) z-scores between baseline and follow-up exams. We generated systolic streamlines for all patients and visually compared their baseline and follow-up exams.Results: The only significant difference between baseline and follow-up exams occurred in AAo z-scores (3.12±2.62 vs. 3.59±2.76, P<0.05) indicating growth of the AAo out of proportion to somatic growth. There were no significant changes in either peak velocity or 3-D wall shear stress between baseline and follow-up exams. Ascending aortic peak velocity at baseline correlated with annual change in AAo z-score (r=0.58, P=0.009). Visual assessment revealed abnormal blood flow patterns, which were unique to each patient and remained stable between baseline and follow-up exams.Conclusion: In our pediatric and young adult BAV cohort, hemodynamic markers and systolic blood flow patterns remained stable over short-term follow-up despite significant AAo growth, suggesting minimal acute disease progression. Baseline AAo peak velocity was a predictor of AAo dilation and might help in determining pediatric patients with BAV who are at risk of increased AAo growth. [ABSTRACT FROM AUTHOR]

Objectives: To compare accelerated real-time cardiac MRI (CMR) using sparse spatial and temporal undersampling and non-linear iterative SENSE reconstruction (RT IS SENSE) with real-time CMR (RT) and segmented CMR (SEG) in a cohort that included atrial fibrillation (AF) patients.Methods: We evaluated 27 subjects, including 11 AF patients, by acquiring steady-state free precession cine images covering the left ventricle (LV) at 1.5 T with SEG (acceleration factor 2, TR 42 ms, 1.8 × 1.8 × 6 mm3), RT (acceleration factor 3, TR 62 ms, 3.0 × 3.0 × 7 mm3), and RT IS SENSE (acceleration factor 9.9-12, TR 42 ms, 2.0 × 2.0 × 7 mm3). We performed quantitative LV functional analysis in sinus rhythm (SR) patients and qualitatively scored image quality, noise and artefact using a 5-point Likert scale in the complete cohort and AF and SR subgroups.Results: There was no difference between LV functional parameters between acquisitions in SR patients. RT IS SENSE short-axis image quality was superior to SEG (4.5 ± 0.6 vs. 3.9 ± 1.1, p = 0.007) and RT (3.8 ± 0.4, p = 0.003). There was reduced artefact in RT IS SENSE compared to SEG (4.4 ± 0.6 vs. 3.8 ± 1.2, p = 0.04), driven by arrhythmia performance. RT IS SENSE short-axis image quality was superior to SEG (4.6 ± 0.5 vs. 3.1 ± 1.0, p < 0.001) in the AF subgroup.Conclusion: Accelerated real-time CMR with iterative sparse SENSE provides excellent clinical performance, especially in patients with AF.Key Points: • Iterative sparse SENSE significantly accelerates real-time cardiovascular MRI acquisitions. • It provides excellent qualitative and quantitative performance in sinus rhythm patients. • It outperforms standard segmented acquisitions in patients with atrial fibrillation. • It improves the trade-off between temporal and spatial resolution in real-time imaging. [ABSTRACT FROM AUTHOR]

An increasing volume of pre-clinical and clinical-translational research is attempting to identify novel biomarkers for improved diagnosis and risk-stratification of chemotherapy-induced cardiotoxicity. Most published animal models have employed weekly intraperitoneal injections of doxorubicin to reach a desired cumulative dose. This approach can be associated with severe systemic toxicity which limits the animal model usefulness, particularly for advanced imaging. In the current study, slow-release subcutaneous doxorubicin pellets demonstrated histopathologic evidence of cardiotoxicity at doses similar to standard human dose-equivalents without limiting animal survival or ability to participate in advanced imaging studies. This approach may provide a more robust cardiotoxicity animal model. [ABSTRACT FROM AUTHOR]

Cardiac MR is considered the gold standard in assessing RV function. The purpose of this study is to evaluate the clinical utility of an investigational iterative reconstruction algorithm in the quantitative assessment of RV function. This technique has the potential to improve the clinical utility of CMR in the evaluation of RV pathologies, particularly in patients with dyspnea, by shortening acquisition times without adversely influencing imaging performance. Segmented cine images were acquired on 9 healthy volunteers and 29 patients without documented RV pathologies using conventional GRAPPA acquisition with factor 2 acceleration (GRAPPA 2), a spatio-temporal TSENSE acquisition with factor 4 acceleration (TSENSE 4), and iteratively reconstructed Sparse SENSE acquisition with factor 4 acceleration (IS-SENSE 4). 14 subjects were re-analyzed and intraclass correlation coefficients (ICC) were calculated and Bland-Altman plots generated to assess agreement. Two independent reviewers qualitatively scored images. Comparison of acquisition techniques was performed using univariate analysis of variance (ANOVA). Differences in RV EF, BSA-indexed ESV (ESVi), BSA-indexed EDV (EDVi), and BSA-indexed SV (SVi) were shown to be statistically insignificant via ANOVA testing. R(2) values for linear regression of TSENSE 4 and IS-SENSE 4 versus GRAPPA 2 were 0.34 and 0.72 for RV-EF, and 0.61 and 0.76 for RV-EDVi. ICC values for intraobserver and interobserver quantification yielded excellent agreement, and Bland-Altman plots assessing agreement were generated as well. Qualitative review yielded small, but statistically significant differences in image quality and noise between TSENSE 4 and IS-SENSE 4. All three techniques were rated nearly artifact free. Segmented imaging acquisitions with IS-SENSE reconstruction and an acceleration factor of 4 accurately and reliably quantitates RV systolic function parameters, while maintaining image quality. TSENSE-4 accelerated acquisitions showed poorer correlation to standard imaging, and inferior interobserver and intraobserver agreement. IS-SENSE has the potential to shorten cine acquisition times by 50 %, improving imaging options in patients with intermittent arrhythmias or difficulties with breath holding. [ABSTRACT FROM AUTHOR]

To evaluate the qualitative and quantitative performance of an accelerated cardiovascular MRI (CMR) protocol that features iterative SENSE reconstruction and spatio-temporal L1-regularization (IS SENSE). Twenty consecutively recruited patients and 9 healthy volunteers were included. 2D steady state free precession cine images including 3-chamber, 4-chamber, and short axis slices were acquired using standard parallel imaging (GRAPPA, acceleration factor = 2), spatio-temporal undersampled TSENSE (acceleration factor = 4), and IS SENSE techniques (acceleration factor = 4). Acquisition times, quantitative cardiac functional parameters, wall motion abnormalities (WMA), and qualitative performance (scale: 1-poor to 5-excellent for overall image quality, noise, and artifact) were compared. Breath-hold times for IS SENSE (3.0 ± 0.6 s) and TSENSE (3.3 ± 0.6) were both reduced relative to GRAPPA (8.4 ± 1.7 s, p < 0.001). No difference in quantitative cardiac function was present between the three techniques (p = 0.89 for ejection fraction). GRAPPA and IS SENSE had similar image quality (4.7 ± 0.4 vs. 4.5 ± 0.6, p = 0.09) while, both techniques were superior to TSENSE (quality: 4.1 ± 0.7, p < 0.001). GRAPPA WMA agreement with IS SENSE was good (κ > 0.60, p < 0.001), while agreement with TSENSE was poor (κ < 0.40, p < 0.001). IS SENSE is a viable clinical CMR acceleration approach to reduce acquisition times while maintaining satisfactory qualitative and quantitative performance. [ABSTRACT FROM AUTHOR]

In patients with bicuspid aortic valve (BAV), beta-blockers (BB) are assumed to slow ascending aorta (AAo) dilation by reducing wall shear stress (WSS) on the aneurysmal segment. The aim of this study was to assess differences in AAo peak velocity and WSS in BAV patients with and without BB therapy. BAV patients receiving BB (BB+, n = 30, age: 47 ± 11 years) or not on BB (BB-, n = 30, age: 46 ± 13 years) and healthy controls (n = 15, age: 43 ± 11 years) underwent 4D flow MRI for the assessment of in vivo aortic 3D blood flow. Peak systolic velocities and 3D WSS were calculated at the anterior and posterior walls of the AAo. Both patient groups had higher maximum and mean WSS relative to the control group (p = 0.001 to p = 0.04). WSS was not reduced in the BB+ group compared to BB- patients in the anterior AAo (maximum: 1.49 ± 0.47 vs. 1.38 ± 0.49 N/m(2), p = 0.99, mean: 0.76 ± 0.2 vs. 0.74 ± 0.18 N/m(2), p = 1.00) or posterior AAo (maximum: 1.45 ± 0.42 vs. 1.39 ± 0.58 N/m(2), p = 1.00; mean: 0.65 ± 0.16 vs. 0.63 ± 0.16 N/m(2), p = 1.00). AAo peak velocity was elevated in patients compared to controls (p < 0.01) but similar for BB+ and BB- groups (p = 0.42). Linear models identified significant relationships between aortic stenosis severity and increased maximum WSS (β = 0.186, p = 0.007) and between diameter at the sinus of Valsalva and reduced mean WSS (β = -0.151, p = 0.045). Peak velocity and systolic WSS were similar for BAV patients irrespective of BB therapy. Further prospective studies are needed to investigate the impact of dosage and duration of BB therapy on aortic hemodynamics and development of aortopathy. [ABSTRACT FROM AUTHOR]