Computed Tomography and Cardiac Magnetic Resonance in Ischemic Heart Disease

Cardiac Magnetic Resonance Left Atrial Strain in the Prediction of Death, Ischemic Stroke, and Heart Failure

BACKGROUND

To determine the prognostic value of left atrial strain (LAS) using cardiac magnetic resonance for predicting death, heart failure, and ischemic stroke in patients with known or suspected coronary artery disease with preserved left ventricular systolic function and no prior history of ischemic stroke, heart failure, or atrial fibrillation.

METHODS AND RESULTS

This retrospective cohort analysis included patients referred for stress cardiac magnetic resonance or myocardial viability studies between September 2017 and December 2019. Patients with impaired left ventricular systolic function (<50%) or a history of atrial fibrillation, stroke, or heart failure were excluded. A multivariable Cox model assessed the prognostic value of LAS, with the primary outcomes being the composite outcomes of all-cause death, ischemic stroke, and heart failure. A total of 2030 participants were included in the study. The average LAS was 24.1±8.5%; 928 had LAS <23%, and 1102 had LAS ≥23%. The mean follow-up duration was 39.9±13.6 months. There were 49 deaths (2.4%), 32 ischemic strokes (1.6%), and 34 heart failure events (1.7%). Patients with LAS <23% were at greater risk for composite outcome, with an adjusted hazard ratio of 2.31 (95% CI, 1.50-3.55).

CONCLUSIONS

LAS by cardiac magnetic resonance has an independent and incremental prognostic value for death, ischemic stroke, and heart failure in patients with preserved left ventricular systolic function. This prognostic value is observed after adjusting for clinical and cardiac magnetic resonance parameters, including left ventricular systolic function, late gadolinium enhancement, and left atrial volume index.

Prognostic value of global longitudinal strain in patients with preserved left ventricular systolic function: A cardiac magnetic resonance real-world study

BACKGROUND

Myocardial strain is a more sensitive parameter for cardiac function evaluation than left ventricular ejection fraction (LVEF). This study aimed to assess the predictive value of left ventricular global longitudinal strain (LV-GLS) by feature tracking-cardiac magnetic resonance (FT-CMR) imaging in patients with known or suspected coronary artery disease (CAD) with preserved left ventricular systolic function.

METHODS

This retrospective cohort analysis enrolled patients with known or suspected CAD who underwent cardiac magnetic resonance imaging from September 2017 to December 2019. LV-GLS was analyzed via feature-tracking analysis. Patients with LVEF <50% were excluded. The composite outcome comprised all-cause death, non-fatal myocardial infarction, and heart failure.

RESULTS

There was a total of 2613 patients. Mean follow-up duration was 39.7 ± 13.9 months. During follow-up, 194 patients (7.4%) experienced a composite outcome. The best cutoff of LV-GLS in the prediction of composite outcome from receiver operating characteristics was -14.4%. Patients were classified into 2 groups according to the LV-GLS; 1489 (57.0%) had LV-GLS <-14.4% and 1124 (43.0%) had LV-GLS ≥-14.4%. Patients with LV-GLS ≥-14.4% had a significantly higher rate of composite outcome than LV-GLS <-14.4% patients (3.59 vs. 1.39 per 100 person-years, respectively; p < 0.001). Multivariable analysis showed that patients with LV-GLS ≥-14.4% had a significantly higher risk of experiencing a composite outcome event compared to global longitudinal strain <-14.4% patients (adjusted hazard ratio: 1.83, 95% confidence interval: 1.28-2.61; p = 0.001).

CONCLUSION

LV-GLS by FT-CMR was shown to be useful for predicting the prognosis of patients with known or suspected CAD with preserved left ventricular systolic function. LV-GLS -14.4% was the identified cutoff for prognostic determination.

Diagnostic performance of coronary computed tomography angiography stenosis score for coronary stenosis

BACKGROUND

Coronary computed tomography angiography stenosis score (CCTA-SS) is a proposed diagnosis score that considers the plaque characteristics, myocardial function, and the diameter reduction rate of the lesions. This study aimed to evaluate the diagnostic performance of the CCTA-SS in seeking coronary artery disease (CAD).

METHODS

The 228 patients with suspected CAD who underwent CCTA and invasive coronary angiography (ICA) procedures were under examination. The diagnostic performance was evaluated with the receiver operating curve (ROC) for CCTA-SS in detecting CAD (defined as a diameter reduction of ≥ 50%) and severe CAD (defined as a diameter reduction of ≥ 70%).

RESULTS

The area under ROC (AUC) of CCTA-SS was 0.909 (95% CI: 0.864-0.943), which was significantly higher than that of CCTA (AUC: 0.826; 95% CI: 0.771-0.873; P = 0.0352) in diagnosing of CAD with a threshold of 50%. The optimal cutoff point of CCTA-SS was 51% with a sensitivity of 90.66%, specificity of 95.65%, positive predictive value of 98.80%, negative predictive value of 72.13%, and accuracy of 91.67%, whereas the optimal cutoff point of CCTA was 55%, and the corresponding values were 87.36%, 93.48%, 98.15%, 65.15%, and 88.60%, respectively. With a threshold of 70%, the performance of CCTA-SS with an AUC of 0.927 (95% CI: 0.885-0.957) was significantly higher than that of CCTA with an AUC of 0.521 (95% CI: 0.454-0.587) (P < 0.0001).

CONCLUSIONS

CCTA-SS significantly improved the diagnostic accuracy of coronary stenosis, including CAD and severe CAD, compared with CCTA.

Coronary artery stenosis quantification in patients with dense calcifications using ultra-high-resolution photon-counting-detector computed tomography

BACKGROUND

To quantify differences in coronary artery stenosis severity in patients with calcified lesions between conventional energy-integrating detector (EID) CT and ultra-high-resolution (UHR) photon-counting-detector (PCD) CT.

METHODS

Patients undergoing clinically indicated coronary CT angiography were prospectively recruited and scanned first on an EID-CT (SOMATOM Force, Siemens Healthineers) and then a PCD-CT (NAEOTOM Alpha, Siemens Healthineers) on the same day. EID-CT was performed with standard mode (192 ​× ​0.6 ​mm detector collimation) following our clinical protocol. PCD-CT scans were performed under UHR mode (120 ​× ​0.2 ​mm detector collimation). For each patient, left main, left anterior descending, right coronary artery, and circumflex were reviewed and the most severe stenosis from dense calcification for each coronary was quantified using commercial software. Additionally, each measured stenosis was assigned a severity category based on percent diameter stenosis, and changes in severity category across EID-CT and PCD-CT were assessed.

RESULTS

A total of 23 patients were enrolled, with 34 coronary artery stenoses analyzed. Stenosis was significantly reduced in PCD-CT compared to EID-CT (p ​< ​0.001), resulting in an average of 11% (SD ​= ​11%) reduction in percent diameter stenosis. Among the 34 lesions, 15 changed in stenosis severity category: 3 went from moderate to minimal, 1 from moderate to mild, 9 from mild to minimal, and 2 from minimal to mild with the use of PCD-CT compared to EID-CT.

CONCLUSION

Use of UHR PCD-CT decreased percent diameter stenosis by an average of 11% relative to EID-CT, resulting in 13 of 34 stenoses being downgraded in stenosis severity category, potentially sparing patients from unnecessary intervention.

Prediction of Hemodynamic-Related Hemolysis in Carotid Stenosis and Aiding in Treatment Planning and Risk Stratification Using Computational Fluid Dynamics

Atherosclerosis affects human health in many ways, leading to disability or premature death due to ischemic heart disease, stroke, or limb ischemia. Poststenotic blood flow disruption may also play an essential role in artery wall impairment linked with hemolysis related to shear stress. The maximum shear stress in the atherosclerotic plaque area is the main parameter determining hemolysis risk. In our work, a 3D internal carotid artery model was built from CT scans performed on patients qualified for percutaneous angioplasty due to its symptomatic stenosis. The obtained stenosis geometries were used to conduct a series of computer simulations to identify critical parameters corresponding to the increase in shear stress in the arteries. Stenosis shape parameters responsible for the increase in shear stress were determined. The effect of changes in the carotid artery size, length, and degree of narrowing on the change in maximum shear stress was demonstrated. Then, a correlation for the quick initial diagnosis of atherosclerotic stenoses regarding the risk of hemolysis was developed. The developed relationship for rapid hemolysis risk assessment uses information from typical non-invasive tests for treated patients. Practical guidelines have been developed regarding which stenosis shape parameters pose a risk of hemolysis, which may be adapted in medical practice.

Comparison of Photon-counting Detector and Energy-integrating Detector CT for Visual Estimation of Coronary Percent Luminal Stenosis

Background Compared with energy-integrating detector (EID) CT, the improved resolution of photon-counting detector (PCD) CT coupled with high-energy virtual monoenergetic images (VMIs) has been shown to decrease calcium blooming on images in phantoms and cadaveric specimens. Purpose To determine the impact of dual-source PCD CT on visual and quantitative estimation of percent diameter luminal stenosis compared with dual-source EID CT in patients. Materials and Methods This prospective study recruited consecutive adult patients from an outpatient facility between January and March 2022. Study participants underwent clinical dual-source EID coronary CT angiography followed by a research dual-source PCD CT examination. For PCD CT, multienergy data were used to create VMIs at 50 and 100 keV. Two readers independently reviewed EID CT images followed by PCD CT images after a washout period. Readers visually graded the most severe stenosis in terms of percent diameter luminal stenosis for the left main, left anterior descending, right, and circumflex coronary arteries, unblinded to scanner type. Quantitative measures of percent stenosis were made using commercial software. Visual and quantitative estimates of percent stenosis were compared between EID CT and PCD CT using the Wilcoxon signed-rank test. Results A total of 25 participants (median age, 59 years [range, 18-78 years]; 16 male participants) were enrolled. On EID CT images, readers 1 and 2 identified 39 and 32 luminal stenoses, respectively, with a percent diameter luminal stenosis greater than 0%. Visual estimates of percent stenosis were lower on PCD CT images than EID CT images (reader 1: median 20.6% [IQR, 8.8%-61.2%] vs 31.8% [IQR, 12.9%-69.7%], P < .001; reader 2: 6.5% [IQR, 0.4%-54.1%] vs 22.9% [IQR, 1.8%-67.4%], P = .002). No difference was observed between EID CT and PCD CT for quantitative measures of percent stenosis (median difference, -1.5% [95% CI: -3.0%, 2.5%]; P = .51). Conclusion Relative to using EID CT, using PCD CT led to decreases in visual estimates of percent stenosis. © RSNA, 2023 See also the editorial by Murphy and Donnelly in this issue.

The Role of Non-Invasive Multimodality Imaging in Chronic Coronary Syndrome: Anatomical and Functional Pathways

Coronary artery disease (CAD) is one of the major causes of mortality and morbidity worldwide, with a high socioeconomic impact. Currently, various guidelines and recommendations have been published about chronic coronary syndromes (CCS). According to the recent European Society of Cardiology guidelines on chronic coronary syndrome, a multimodal imaging approach is strongly recommended in the evaluation of patients with suspected CAD. Today, in the current practice, non-invasive imaging methods can assess coronary anatomy through coronary computed tomography angiography (CCTA) and/or inducible myocardial ischemia through functional stress testing (stress echocardiography, cardiac magnetic resonance imaging, single photon emission computed tomography-SPECT, or positron emission tomography-PET). However, recent trials (ISCHEMIA and REVIVED) have cast doubt on the previous conception of the management of patients with CCS, and nowadays it is essential to understand the limitations and strengths of each imaging method and, specifically, when to choose a functional approach focused on the ischemia versus a coronary anatomy-based one. Finally, the concept of a pathophysiology-driven treatment of these patients emerged as an important goal of multimodal imaging, integrating 'anatomical' and 'functional' information. The present review aims to provide an overview of non-invasive imaging modalities for the comprehensive management of CCS patients.

Papillary-Muscle-Derived Radiomic Features for Hypertrophic Cardiomyopathy versus Hypertensive Heart Disease Classification

Purpose: This study aimed to assess the value of radiomic features derived from the myocardium (MYO) and papillary muscle (PM) for left ventricular hypertrophy (LVH) detection and hypertrophic cardiomyopathy (HCM) versus hypertensive heart disease (HHD) differentiation. Methods: There were 345 subjects who underwent cardiovascular magnetic resonance (CMR) examinations that were analyzed. After quality control and manual segmentation, the 3D radiomic features were extracted from the MYO and PM. The data were randomly split into training (70%) and testing (30%) datasets. Feature selection was performed on the training dataset. Five machine learning models were evaluated using the MYO, PM, and MYO+PM features in the detection and differentiation tasks. The optimal differentiation model was further evaluated using CMR parameters and combined features. Results: Six features were selected for the MYO, PM, and MYO+PM groups. The support vector machine models performed best in both the detection and differentiation tasks. For LVH detection, the highest area under the curve (AUC) was 0.966 in the MYO group. For HCM vs. HHD differentiation, the best AUC was 0.935 in the MYO+PM group. Comparing the radiomics models to the CMR parameter models for the differentiation tasks, the radiomics models achieved significantly improved the performance (p = 0.002). Conclusions: The radiomics model with the MYO+PM features showed similar performance to the models developed from the MYO features in the detection task, but outperformed the models developed from the MYO or PM features in the differentiation task. In addition, the radiomic models performed better than the CMR parameters' models.

The value of CMR Left ventricular strain analysis in evaluating ICM

The purpose of this article is to investigate the value of cardiac magnetic resonance imaging (CMR) derived left ventricular strain parameters in evaluation of ischemic cardiomyopathy (ICM). Thirty-one ICM patients and nineteen non-cardiomyopathy (non-CM) patients who performed CMR examinations during the same period were selected for this retrospective study. The basic clinical data, CMR left ventricular function parameters, left ventricular strain parameters were compared among the left ventricular ejection fraction (LVEF) preserved ICM group, the LVEF impaired ICM group and the non-CM group. The differences of MyoGCS (-21.9 ± 1.9 vs. -18.9 ± 2.7 P<0.001), MyoGLS (-20.8 ± 2.3 vs. -17.0 ± 2.9 P<0.001) and EndoGLS (-22.2 ± 3.1 vs. -17.6 ± 3.7 P<0.001) between LVEF preserved ICM group and non-CM group were statistically significant, while the differences of left heart function parameters between the two groups were not statistically significant (P > 0.05). The left ventricular strain analysis can be used to assess cardiac functional and morphological alterations in ICM patients prior to changes of left ventricular function parameters, which has high clinical significance.

Emerging molecular imaging targets and tools for myocardial fibrosis detection

Myocardial fibrosis is the heart's common healing response to injury. While initially seeking to optimize the strength of diseased tissue, fibrosis can become maladaptive, producing stiff poorly functioning and pro-arrhythmic myocardium. Different patterns of fibrosis are associated with different myocardial disease states, but the presence and quantity of fibrosis largely confer adverse prognosis. Current imaging techniques can assess the extent and pattern of myocardial scarring, but lack specificity and detect the presence of established fibrosis when the window to modify this process may have ended. For the first time, novel molecular imaging methods, including gallium-68 (68Ga)-fibroblast activation protein inhibitor positron emission tomography (68Ga-FAPI PET), may permit highly specific imaging of fibrosis activity. These approaches may facilitate earlier fibrosis detection, differentiation of active vs. end-stage disease, and assessment of both disease progression and treatment-response thereby improving patient care and clinical outcomes.

Left Ventricular Adverse Remodeling in Ischemic Heart Disease: Emerging Cardiac Magnetic Resonance Imaging Biomarkers

Post-ischemic left ventricular (LV) remodeling is a biologically complex process involving myocardial structure, LV shape, and function, beginning early after myocardial infarction (MI) and lasting until 1 year. Adverse remodeling is a post-MI maladaptive process that has been associated with long-term poor clinical outcomes. Cardiac Magnetic Resonance (CMR) is the best tool to define adverse remodeling because of its ability to accurately measure LV end-diastolic and end-systolic volumes and their variation over time and to characterize the underlying myocardial changes. Therefore, CMR is the gold standard method to assess in vivo myocardial infarction extension and to detect the presence of microvascular obstruction and intramyocardial hemorrhage, both associated with adverse remodeling. In recent times, new CMR quantitative biomarkers emerged as predictive of post-ischemic adverse remodeling, such as T1 mapping, myocardial strain, and 4D flow. Additionally, CMR T1 mapping imaging may depict infarcted tissue and assess diffuse myocardial fibrosis by using surrogate markers such as extracellular volume fraction, which may predict functional recovery or risk stratification of remodeling. Finally, there is emerging evidence supporting the utility of intracavitary blood flow kinetic energy and hemodynamic features assessed by the 4D flow CMR technique as early predictors of remodeling.

Exploring the Potential Mechanism of Danshen in the Treatment of Concurrent Ischemic Heart Disease and Depression Using Network Pharmacology, Molecular Docking, and Molecular Dynamics Simulation

Objective: This study aimed to explore the potential targets and mechanism of action of Danshen in treating concurrent ischemic heart disease (IHD) and depression using network pharmacology, molecular docking, and molecular dynamics simulation (MDS). Methods: The Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was used to obtain active ingredients and targets of Danshen. Candidate targets for IHD and depression were obtained from the Genecards and DisGeNet databases. The protein–protein interaction (PPI) network was constructed using the STRING database and the Cytoscape 3.8.2 software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed using the Metascape database and the GlueGO package of the Cytoscape 3.8.2 software. Molecular docking was performed using Autodock 1.5.6 and Vina, and the MDS was completed using GROMACS 5.1.2. Results: We obtained 65 active ingredients of Danshen with 131 candidate targets and 39 intersection targets of the active ingredients and diseases. Luteolin, tanshinone IIA, and salviolone were the core active ingredients, and AKT1, TNF, IL-6, MMP9, CASP3, IL-10, PTGS2, STAT3, PPARG, IL-4, EGFR, MAPK14, NOS3, and EDN1 were the core targets. The GO and KEGG pathway enrichment analyses revealed that the intersection targets were mainly enriched in positive regulation of protein phosphorylation, blood circulation, IL-17 signaling pathway, VEGF signaling pathway, and JAK/STAT signaling pathway. The molecular docking revealed that the core active ingredients had a good affinity for the core targets. The results of MDS revealed that the protein-ligand complexes were stable. Conclusions: This study used network pharmacology to analyze the potential mechanism of action of Danshen in the treatment of concurrent IHD and depression. Additionally, the study provided a theoretical basis for further studying the pharmacological mechanisms and targets of Danshen.

Cardiovascular Risk Assessment and Management for Pediatricians

Childhood and adolescence provide a unique window of opportunity to prevent atherosclerotic cardiovascular disease later in life, especially for pediatric groups at risk. The growing list of pediatric groups at risk includes individuals with chronic inflammatory disorders, organ transplants, familial hypercholesterolemia, endocrine disorders, childhood cancer, chronic kidney diseases, congenital heart diseases, and premature birth, as well as increasing numbers of children and adolescents with traditional risk factors such as obesity, hypertension, hyperlipidemia, and hyperglycemia. Here, we focus on recent advances in cardiovascular risk assessment and management and their implications for pediatric practice. First, hyperlipidemia and hyperglycemia are highly prevalent in the young, with hyperlipidemia occurring in 14.6% and hyperglycemia in 16.4% of children and adolescents with a normal weight. Implementation of nonfasting lipid and glycated hemoglobin screening in youth at risk is emerging as a promising avenue to improve testing compliance and lipid and glucose management. Second, blood pressure, lipid, and glucose management in youth at risk are reviewed in depth. Third, multisite and multimodal assessment of early atherosclerosis is discussed as a way to capture the complexity of atherosclerosis as a systemic disease. In addition to conventional carotid intima-media thickness measurements, the measurement of aortic pulse wave velocity and peripheral arterial tonometry can advance the assessment of early atherosclerosis in pediatrics. Finally, we make a plea for lifetime atherosclerotic cardiovascular disease risk stratification that integrates disease-associated risk factors and traditional risk factors and could facilitate tailored cardiovascular risk management in growing numbers of children and adolescents at risk.

Myocardial Function Prediction After Coronary Artery Bypass Grafting Using MRI Radiomic Features and Machine Learning Algorithms

The main aim of the present study was to predict myocardial function improvement in cardiac MR (LGE-CMR) images in patients after coronary artery bypass grafting (CABG) using radiomics and machine learning algorithms. Altogether, 43 patients who had visible scars on short-axis LGE-CMR images and were candidates for CABG surgery were selected and enrolled in this study. MR imaging was performed preoperatively using a 1.5-T MRI scanner. All images were segmented by two expert radiologists (in consensus). Prior to extraction of radiomics features, all MR images were resampled to an isotropic voxel size of 1.8 × 1.8 × 1.8 mm³. Subsequently, intensities were quantized to 64 discretized gray levels and a total of 93 features were extracted. The applied algorithms included a smoothly clipped absolute deviation (SCAD)-penalized support vector machine (SVM) and the recursive partitioning (RP) algorithm as a robust classifier for binary classification in this high-dimensional and non-sparse data. All models were validated with repeated fivefold cross-validation and 10,000 bootstrapping resamples. Ten and seven features were selected with SCAD-penalized SVM and RP algorithm, respectively, for CABG responder/non-responder classification. Considering univariate analysis, the GLSZM gray-level non-uniformity-normalized feature achieved the best performance (AUC: 0.62, 95% CI: 0.53-0.76) with SCAD-penalized SVM. Regarding multivariable modeling, SCAD-penalized SVM obtained an AUC of 0.784 (95% CI: 0.64-0.92), whereas the RP algorithm achieved an AUC of 0.654 (95% CI: 0.50-0.82). In conclusion, different radiomics texture features alone or combined in multivariate analysis using machine learning algorithms provide prognostic information regarding myocardial function in patients after CABG.

State-of-the-Art Review: Technical and Imaging Considerations in Hybrid Transcatheter and Minimally Invasive Left Ventricular Reconstruction for Ischemic Heart Failure

Negative left ventricular (LV) remodeling consequent to acute myocardial infarction (AMI) is characterized by an increase in LV volumes in the presence of a depressed LVEF. In order to restore the shape, size, and function of the LV, operative treatment options to achieve volume reduction and shape reconstruction should be considered. In the past decade, conventional surgical LV reconstruction through a full median sternotomy has evolved towards a hybrid transcatheter and less invasive LV reconstruction. In order to perform a safe and effective hybrid LV reconstruction, thorough knowledge of the technical considerations and adequate use of multimodality imaging both pre- and intraoperatively are fundamental. In addition, a comprehensive understanding of the individual procedural steps from both a cardiological and surgical point of view is required.

Contrast-enhanced computed tomography assessment of aortic stenosis

OBJECTIVES

Non-contrast CT aortic valve calcium scoring ignores the contribution of valvular fibrosis in aortic stenosis. We assessed aortic valve calcific and non-calcific disease using contrast-enhanced CT.

METHODS

This was a post hoc analysis of 164 patients (median age 71 (IQR 66-77) years, 78% male) with aortic stenosis (41 mild, 89 moderate, 34 severe; 7% bicuspid) who underwent echocardiography and contrast-enhanced CT as part of imaging studies. Calcific and non-calcific (fibrosis) valve tissue volumes were quantified and indexed to annulus area, using Hounsfield unit thresholds calibrated against blood pool radiodensity. The fibrocalcific ratio assessed the relative contributions of valve fibrosis and calcification. The fibrocalcific volume (sum of indexed non-calcific and calcific volumes) was compared with aortic valve peak velocity and, in a subgroup, histology and valve weight.

RESULTS

Contrast-enhanced CT calcium volumes correlated with CT calcium score (r=0.80, p<0.001) and peak aortic jet velocity (r=0.55, p<0.001). The fibrocalcific ratio decreased with increasing aortic stenosis severity (mild: 1.29 (0.98-2.38), moderate: 0.87 (1.48-1.72), severe: 0.47 (0.33-0.78), p<0.001) while the fibrocalcific volume increased (mild: 109 (75-150), moderate: 191 (117-253), severe: 274 (213-344) mm³/cm²). Fibrocalcific volume correlated with ex vivo valve weight (r=0.72, p<0.001). Compared with the Agatston score, fibrocalcific volume demonstrated a better correlation with peak aortic jet velocity (r=0.59 and r=0.67, respectively), particularly in females (r=0.38 and r=0.72, respectively).

CONCLUSIONS

Contrast-enhanced CT assessment of aortic valve calcific and non-calcific volumes correlates with aortic stenosis severity and may be preferable to non-contrast CT when fibrosis is a significant contributor to valve obstruction.

Grounding of Pilots: Medical Reasons and Recommendations for Prevention

BACKGROUND: This article presents the results of an EASA-commissioned study aimed at analyzing the medical causes of grounding of a broad European pilot population and recommending measures to reduce the risk of in-flight incapacitation in commercial air transport pilots.METHOD: European National Aviation Authorities (NAAs) were requested to provide data concerning the total number of pilots that were examined, their age and license category, number of unfit pilots, and the medical causes of each case of grounding. Diagnoses were classified according to the format and definitions laid down in Commission Regulation (EU) No. 1178/2011 Part Med.RESULTS: Analyzed were 82,435 cases assessed by 6 NAAs. Of these cases, 2.1% were assessed as unfit to fly. Frequent causes for grounding a pilot were cardiovascular (19%), psychiatric (11%), neurological (10%), and psychological (9%). Cardiovascular conditions were the most frequent cause for grounding in the older age groups, with 21% in the age 51-60 cohort, 28% in the age 61-65 cohort, and 48% in those beyond 65 yr. Psychiatric and psychological diagnoses were most frequent in the age 20-40 cohort.DISCUSSION: Cardiovascular conditions were the most frequent cause for grounding. Cardiovascular diseases (CVD) are associated with modifiable risk factors. Tackling these risk factors gives aeromedical examiners the opportunity to improve the health of pilots and reduce CVD-related flight safety risks by reducing the number of pilots at risk of in-flight incapacitation. The mandatory periodical medical examination of pilots provides an excellent framework for risk prevention and follow-up of preventive measures.Simons R, Maire R, Van Drongelen A, Valk P. Grounding of pilots: medical reasons and recommendations for prevention. Aerosp Med Hum Perform. 2021; 92(12):950-955.

Multimodality imaging of myocardial viability: an expert consensus document from the European Association of Cardiovascular Imaging (EACVI)

In clinical decision making, myocardial viability is defined as myocardium in acute or chronic coronary artery disease and other conditions with contractile dysfunction but maintained metabolic and electrical function, having the potential to improve dysfunction upon revascularization or other therapy. Several pathophysiological conditions may coexist to explain this phenomenon. Cardiac imaging may allow identification of myocardial viability through different principles, with the purpose of prediction of therapeutic response and selection for treatment. This expert consensus document reviews current insight into the underlying pathophysiology and available methods for assessing viability. In particular the document reviews contemporary viability imaging techniques, including stress echocardiography, single photon emission computed tomography, positron emission tomography, cardiovascular magnetic resonance, and computed tomography and provides clinical recommendations for how to standardize these methods in terms of acquisition and interpretation. Finally, it presents clinical scenarios where viability assessment is clinically useful.

Eosinophilic heart disease: diagnostic and prognostic assessment by cardiac magnetic resonance

AIMS 

Eosinophilic heart disease (EHD) is a rare cardiac condition with a wide spectrum of phenotypes. The diagnostic and prognostic value of cardiac magnetic resonance (CMR) in EHD remains unknown.

METHODS AND RESULTS 

This was a retrospective analysis of 250 patients with eosinophilia referred for a CMR scan (period 2000-2020). CMR data sets and clinical/laboratory data were collected. Patients were followed up for a mean of 24 months (range 1-224) for the composite endpoint of death, acute coronary syndrome, hospitalization for acute heart failure, malignant ventricular arrhythmias, or the need for implantable cardiac defibrillator/pacemaker. The main objectives were to explore the diagnostic value of CMR in EHD; relationships between cardiac function, late gadolinium enhancement (LGE), and EHD phenotypes; and the prognostic value of fibrosis and oedema by CMR. The prevalence of findings compatible with EHD was 39% (patients with cardiac symptoms: 57% vs. screening: 20%, P < 0.001). EHD phenotypes included subendocardial LGE (n = 58), mid-wall/subepicardial LGE (n = 26), pericarditis (n = 5) or dilated cardiomyopathy (n = 8). Myocardial oedema was present in 10% of patients. Intracardiac thrombi (7%) were associated with EHD phenotype (χ2=47.3, P = 1.3×10-8). LGE extent correlated with LVEDVi (rho = 0.268, P = 5.3×10-5) and LVEF (rho=-0.415, P = 8.6×10-11). A CMR scan positive for EHD [hazard ratio (HR) = 5.61, 95% confidence interval (CI): 1.82-17.89, P = 0.0026] or a subendocardial LGE pattern (HR = 5.13, 95% CI: 1.29-20.38, P = 0.020) were independently associated with the composite clinical endpoint.

CONCLUSION 

The diagnostic yield of CMR screening in patients with persistent eosinophilia, even if asymptomatic, is high. The extent of subendocardial fibrosis correlates with LV remodelling and independently predicts clinical outcomes in patients with eosinophilia.

Thoracic Manifestations of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is one of the most common chronic systemic inflammatory diseases and the most common chronic inflammatory arthritis. Classically a progressive symmetric polyarthritis, RA is characterized by inflammation, erosions, bone loss, and joint destruction. Up to half of patients with RA exhibit extra-articular manifestations (EAMs), which may precede articular disease and are more common in patients with seropositive RA (patients with detectable serum levels of rheumatoid factor and/or anticitrullinated peptide antibodies). Cardiovascular and pulmonary EAMs are the largest contributors to morbidity and mortality in RA and may be especially devastating. Imaging has a significant role in diagnosing these EAMs and assessing response to treatment. Although treatment with disease-modifying antirheumatic drugs has redefined the natural history of RA and helped many patients achieve low disease activity, patients are at risk for treatment-related complications, as well as infections. The clinical features of drug-induced lung disease and infection can overlap considerably with those of EAMs, presenting a diagnostic challenge. Radiologists, by recognizing the imaging characteristics and evolution of these various processes, are essential in diagnosing and distinguishing among EAMs, treatment-related complications, and unrelated processes and formulating an appropriate differential diagnosis. Moreover, recognizing these disease processes at imaging and contextualizing imaging findings with clinical information and laboratory and pathologic findings can facilitate definitive diagnosis and proper treatment. The authors review the articular and extra-articular thoracic imaging manifestations of RA, including cardiovascular, respiratory, and pleural diseases, as well as treatment-related complications and common infections. ^©RSNA, 2021.

Ultra-high resolution, 3-dimensional magnetic resonance imaging of the atherosclerotic vessel wall at clinical 7T

Accurate quantification and characterization of atherosclerotic plaques with MRI requires high spatial resolution acquisitions with excellent image quality. The intrinsically better signal-to-noise ratio (SNR) at high-field clinical 7T compared to the widely employed lower field strengths of 1.5 and 3T may yield significant improvements to vascular MRI. However, 7T atherosclerosis imaging also presents specific challenges, related to local transmit coils and B1 field inhomogeneities, which may overshadow these theoretical gains. We present the development and evaluation of 3D, black-blood, ultra-high resolution vascular MRI on clinical high-field 7T in comparison lower-field 3T. These protocols were applied for in vivo imaging of atherosclerotic rabbits, which are often used for development, testing, and validation of translatable cardiovascular MR protocols. Eight atherosclerotic New Zealand White rabbits were imaged on clinical 7T and 3T MRI scanners using 3D, isotropic, high (0.63 mm3) and ultra-high (0.43 mm3) spatial resolution, black-blood MR sequences with extensive spatial coverage. Following imaging, rabbits were sacrificed for validation using fluorescence imaging and histology. Image quality parameters such as SNR and contrast-to-noise ratio (CNR), as well as morphological and functional plaque measurements (plaque area and permeability) were evaluated at both field strengths. Using the same or comparable imaging parameters, SNR and CNR were in general higher at 7T compared to 3T, with a median (interquartiles) SNR gain of +40.3 (35.3-80.1)%, and a median CNR gain of +68.1 (38.5-95.2)%. Morphological and functional parameters, such as vessel wall area and permeability, were reliably acquired at 7T and correlated significantly with corresponding, widely validated 3T vessel wall MRI measurements. In conclusion, we successfully developed 3D, black-blood, ultra-high spatial resolution vessel wall MRI protocols on a 7T clinical scanner. 7T imaging was in general superior to 3T with respect to image quality, and comparable in terms of plaque area and permeability measurements.

Single breath-hold compressed sensing real-time cine imaging to assess left ventricular motion in myocardial infarction

PURPOSE

To evaluate the reliability of a real-time compressed sensing (CS) cine sequence for the detection of left ventricular wall motion disorders after myocardial infarction in comparison with the reference steady-state free precession cine sequence.

MATERIALS AND METHODS

One hundred consecutive adult patients referred for either initial work-up or follow-up by cardiac magnetic resonance (CMR) in the context of myocardial infarction were prospectively included. There were 77 men and 23 women with a mean age of 63.12±11.3 (SD) years (range: 29-89 years). Each patient underwent the reference segmented multi-breath-hold steady-state free precession cine sequence including one short-axis stack and both vertical and horizontal long-axis slices (SSFP_ref) and the CS real-time single-breath-hold evaluated sequence (CS_rt) providing the same slices. Wall motion disorders were independently and blindly assessed with both sequences by two radiologists, using the American Heart Association left ventricle segmentation. Paired Wilcoxon signed-rank test was used to search for differences in wall motion disorders conspicuity between both sequences and receiver operating characteristic curve (ROC) analysis was performed to assess the diagnosis performance of CS_rt sequence using SSFP_ref as the reference method.

RESULTS

Each patient had at least one cardiac segment with wall motion abnormality on SSFP_ref and CS_rt images. The 1700 segments analyzed with SSFP_ref were classified as normokinetic (360/1700; 21.2%), hypokinetic (783/1700; 46.1%), akinetic (526/1700; 30.9%) or dyskinetic (31/1700; 1.8%). Sensitivity and specificity of the CS sequence were 99.6% (95% CI: 99.1-99.9%) and 99.7% (95% CI: 98.5-100%), respectively. Area under ROC of CS_rt diagnosis performance was 0.997 (95% CI: 0.993-0.999).

CONCLUSION

CS real-time cine imaging significantly reduces acquisition time without compromising the conspicuity of left ventricular -wall motion disorders in the context of myocardial infarction.

Cardiovascular magnetic resonance imaging for structural heart disease

Cardiovascular magnetic resonance (CMR) has increasingly become a powerful imaging technique over the past few decades due to increasing knowledge about clinical applications, operator experience and technological advances, including the introduction of high field strength magnets, leading to improved signal-to-noise ratio. Its success is attributed to the free choice of imaging planes, the wide variety of imaging techniques, and the lack of harmful radiation. Developments in CMR have led to the accurate evaluation of cardiac structure, function and tissues characterisation, so this non-invasive technique has become a powerful tool for a broad range of cardiac pathologies. This review will provide an introduction of magnetic resonance imaging (MRI) physics, an overview of the current techniques and clinical application of CMR in structural heart disease, and illustrated examples of its use in clinical practice.

Emerging techniques in atherosclerosis imaging

Atherosclerosis is a chronic immunomodulated disease that affects multiple vascular beds and results in a significant worldwide disease burden. Conventional imaging modalities focus on the morphological features of atherosclerotic disease such as the degree of stenosis caused by a lesion. Modern CT, MR and positron emission tomography scanners have seen significant improvements in the rapidity of image acquisition and spatial resolution. This has increased the scope for the clinical application of these modalities. Multimodality imaging can improve cardiovascular risk prediction by informing on the constituency and metabolic processes within the vessel wall. Specific disease processes can be targeted using novel biological tracers and "smart" contrast agents. These approaches have the potential to inform clinicians of the metabolic state of atherosclerotic plaque. This review will provide an overview of current imaging techniques for the imaging of atherosclerosis and how various modalities can provide information that enhances the depiction of basic morphology.

Feasibility of Coronary 18F-Sodium Fluoride Positron-Emission Tomography Assessment With the Utilization of Previously Acquired Computed Tomography Angiography

BACKGROUND

We assessed the feasibility of utilizing previously acquired computed tomography angiography (CTA) with subsequent positron-emission tomography (PET)-only scan for the quantitative evaluation of ¹⁸F-NaF PET coronary uptake.

METHODS AND RESULTS

Forty-five patients (age 67.1±6.9 years; 76% males) underwent CTA (CTA1) and combined ¹⁸F-NaF PET/CTA (CTA2) imaging within 14 [10, 21] days. We fused CTA1 from visit 1 with ¹⁸F-NaF PET (PET) from visit 2 and compared visual pattern of activity, maximal standard uptake (SUVmax) values, and target to background ratio (TBR) measurements on (PET/CTA1) fused versus hybrid (PET/CTA2). On PET/CTA2, 226 coronary plaques were identified. Fifty-eight coronary segments from 28 (62%) patients had high ¹⁸F-NaF uptake (TBR >1.25), whereas 168 segments had lesions with ¹⁸F-NaF TBR ≤1.25. Uptake in all lesions was categorized identically on coregistered PET/CTA1. There was no significant difference in ¹⁸F-NaF uptake values between PET/CTA1 and PET/CTA2 (SUVmax, 1.16±0.40 versus 1.15±0.39; P=0.53; TBR, 1.10±0.45 versus 1.09±0.46; P=0.55). The intraclass correlation coefficient for SUVmax and TBR was 0.987 (95% CI, 0.983-0.991) and 0.986 (95% CI, 0.981-0.992). There was no fixed or proportional bias between PET/CTA1 and PET/CTA2 for SUVmax and TBR. Cardiac motion correction of PET scans improved reproducibility with tighter 95% limits of agreement (±0.14 for SUVmax and ±0.15 for TBR versus ±0.20 and ±0.20 on diastolic imaging; P<0.001).

CONCLUSIONS

Coronary CTA/PET protocol with CTA first followed by PET-only allows for reliable and reproducible quantification of ¹⁸F-NaF coronary uptake. This approach may facilitate selection of high-risk patients for PET-only imaging based on results from prior CTA, providing a practical workflow for clinical application.

Normal values of aortic dimensions assessed by multidetector computed tomography in the Copenhagen General Population Study

Aims

Accurate assessment of aortic dimensions can be achieved using contrast-enhanced computed tomography. The aim of this study was to define normal values and determinants of aortic dimensions throughout multiple key anatomical landmarks of the aorta in healthy individuals from the Copenhagen General Population Study.

Methods and results

The study group consisted of 902 healthy subjects selected from 3000 adults undergoing cardiovascular thoracic and abdominal computed tomography-angiography (CTA), where systematic measurements of aortic dimensions were performed retrospectively. Individuals included were without any of the following predefined cardiovascular risk factors: (i) self-reported angina pectoris; (ii) hypertension; (iii) hypercholesterolaemia; (iv) taking cardiovascular prescribed medication including diuretics, statins, or aspirin; (v) overweight (defined as body mass index ≥30 kg/m2); (vi) diabetes mellitus (self-reported or blood glucose >8 mmol/L); and (vii) chronic obstructive pulmonary disease. Maximal aortic diameters were measured at seven aortic regions: sinuses of Valsalva, sinotubular junction, ascending aorta, mid-descending aorta, abdominal aorta at the diaphragm, abdominal aorta at the coeliac trunk, and infrarenal abdominal aorta. Median age was 52 years, and 396 (40%) were men. Men had significantly larger aortic diameters at all levels compared with women (P < 0.001). Multivariable analysis revealed that sex, age, and body surface area were associated with increasing aortic dimensions.

Conclusion

Normal values of maximal aortic dimensions at key aortic anatomical locations by contrast-enhanced CTA have been defined. Age, sex, and body surface area were significantly associated with these measures at all levels of aorta. Aortic dimensions follow an almost identical pattern throughout the vessel regardless of sex.

Recent Advances in Cardiac Magnetic Resonance Imaging

Cardiac magnetic resonance (CMR) imaging provides accurate anatomic information and advanced soft contrast, making it the reference standard for assessing cardiac volumes and systolic function. In this review, we summarize the recent advances in CMR sequences. New technical development has widened the use of CMR imaging beyond the simple characterization of myocardial scars and assessment of contractility. These novel CMR sequences offer comprehensive assessments of coronary plaque characterization, myocardial fiber orientation, and even metabolic activity, and they can be readily applied in clinical settings. CMR imaging is able to provide new insights into understanding the pathophysiologic process of underlying cardiac disease, and it can help physicians choose the best treatment strategies. Although several limitations, including the high cost and time-consuming process, have limited the widespread clinical use of CMR imaging so far, recent advances in software and hardware technologies have made the future more promising.

Nanobody-Facilitated Multiparametric PET/MRI Phenotyping of Atherosclerosis

OBJECTIVES

This study sought to develop an integrative positron emission tomography (PET) with magnetic resonance imaging (MRI) procedure for accurate atherosclerotic plaque phenotyping, facilitated by clinically approved and nanobody radiotracers.

BACKGROUND

Noninvasive characterization of atherosclerosis remains a challenge in clinical practice. The limitations of current diagnostic methods demonstrate that, in addition to atherosclerotic plaque morphology and composition, disease activity needs to be evaluated.

METHODS

We screened 3 nanobody radiotracers targeted to different biomarkers of atherosclerosis progression, namely vascular cell adhesion molecule (VCAM)-1, lectin-like oxidized low-density lipoprotein receptor (LOX)-1, and macrophage mannose receptor (MMR). The nanobodies, initially radiolabeled with copper-64 (⁶⁴Cu), were extensively evaluated in Apoe^–/– mice and atherosclerotic rabbits using a combination of in vivo PET/MRI readouts and ex vivo radioactivity counting, autoradiography, and histological analyses.

RESULTS

The 3 nanobody radiotracers accumulated in atherosclerotic plaques and displayed short circulation times due to fast renal clearance. The MMR nanobody was selected for labeling with gallium-68 (⁶⁸Ga), a short-lived radioisotope with high clinical relevance, and used in an ensuing atherosclerosis progression PET/MRI study. Macrophage burden was longitudinally studied by ⁶⁸Ga-MMR–PET, plaque burden by T2-weighted MRI, and neovascularization by dynamic contrast-enhanced (DCE) MRI. Additionally, inflammation and microcalcifications were evaluated by fluorine-18 (¹⁸F)-labeled fluorodeoxyglucose (¹⁸F-FDG) and ¹⁸F-sodium fluoride (¹⁸F-NaF) PET, respectively. We observed an increase in all the aforementioned measures as disease progressed, and the imaging signatures correlated with histopathological features.

CONCLUSIONS

We have evaluated nanobody-based radiotracers in rabbits and developed an integrative PET/MRI protocol that allows noninvasive assessment of different processes relevant to atherosclerosis progression. This approach allows the multiparametric study of atherosclerosis and can aid in early stage anti-atherosclerosis drug trials.

Semi-automated QRS score as a predictor of survival in CRT treated patients with strict left bundle branch block

BACKGROUND

Cardiac Resynchronization Therapy (CRT) is widely used for treating selected heart failure patients, but patients with myocardial scar respond worse to treatment. The Selvester QRS scoring system estimates myocardial scar burden using 12-lead ECG. This study's objective was to investigate the scores correlation to mortality in a CRT population.

METHODS AND RESULTS

Data on consecutive CRT patients was collected. 401 patients with LBBB and available ECG data were included in the study. QuAReSS software was used to perform Selvester scoring. Mean Selvester score was 6.4, corresponding to 19% scar burden. The endpoint was death or heart transplant; outcome was analyzed using Cox proportional hazards models. A Selvester score >8 was significantly associated with higher risk of the combined endpoint (HR 1.59, p=.014, CI 1.09-2.3).

CONCLUSION

Higher Selvester scores correlate to mortality in CRT patients with strict LBBB and might be of value in prognosticating survival.

Magnetic resonance imaging in heart failure, including coronary imaging: numbers, facts, and challenges

Coronary artery disease (CAD) is a major risk factor for the incidence and progression of heart failure (HF). HF is characterized by a substantial morbidity and mortality and its lifetime risk is estimated at approximately 20% for men and women. As patients are in most cases identified only after developing overt clinical symptoms, detecting early stages of CAD and HF is of paramount importance. Due to its non‐invasiveness, excellent soft‐tissue contrast, high spatial resolution, and multiparametric nature, cardiovascular magnetic resonance (CMR) imaging has emerged as a promising radiation‐free technique to assess a wide range of cardiovascular diseases such as CAD or HF, enabling a comprehensive evaluation of myocardial anatomy, regional and global function, and viability with the additional benefit of in vivo tissue characterization. CMR has the potential to enhance our understanding of coronary atherosclerosis and the aetiology of HF on functional and biological levels, to identify patients at risk for CAD or HF, and to enable individualized patient management and improved outcomes. Even though larger‐scale studies on the different applications of CMR for the assessment of heart failure are scarce, recent research highlighted new possible clinical applications for CMR in the evaluation of CAD and HF.

Role of Cardiac Magnetic Resonance Imaging in Myocardial Infarction

PURPOSE OF REVIEW

The purpose of the present paper is to analytically review the diagnostic and prognostic role of CMR in ST-segment elevation myocardial infarction (STEMI) survivors. Percutaneous coronary intervention (PCI) is the treatment of choice in patients STEMI. However, risk of future events remains substantial. Assessment of the extent of myocardial infarction (MI), cardiac function and ventricular remodelling has become the focus of recent studies. Electrocardiography, angiography and echocardiography parameters, as well as risk scores, lack sensitivity and reproducibility in predicting future cardiovascular events. A major advantage of cardiac magnetic resonance imaging (CMR) is that it provides myocardial tissue characterization.

RECENT FINDINGS

CMR is able to quantify both reversible and irreversible myocardial injury and correlates with future events. This review will illustrate how microvascular function indices (myocardial salvage index, presence and amount of microvascular obstruction and intramyocardial haemorrhage) detectable by CMR add prognostic information and could impact on future strategies to improve outcomes in revascularized patients.

Editor-in-Chief's Top Picks From 2016: Part Two

Each week, I record audio summaries for every article in JACC, as well as an issue summary. While this process has been incredibly time-consuming, I have become quite familiar with every paper that we publish. Thus, I personally select papers (both original investigations and review articles) from 15 distinct specialties each year for your review. In addition to my personal choices, I have included manuscripts that have been the most accessed or downloaded on our websites, as well as those selected by the JACC Editorial Board members. In order to present the full breadth of this important research in a consumable fashion, we will present these manuscripts in this issue of JACC. Part One included the sections: Basic & Translational Research, Cardiac Failure, Cardiomyopathies/Myocardial & Pericardial Diseases, Congenital Heart Disease, Coronary Disease & Interventions, and CVD Prevention & Health Promotion. Part Two includes the sections: CV Medicine & Society, Hypertension, Imaging, Metabolic & Lipid Disorders, Rhythm Disorders, Valvular Heart Disease, and Vascular Medicine (1-84).

Cardiac Imaging in the Diagnosis of Coronary Artery Disease

Coronary artery disease (CAD) continues to be a leading cause of morbidity and mortality worldwide. Although invasive coronary angiography has previously been the gold standard in establishing the diagnosis of CAD, there is a growing shift to more appropriately use the cardiac catheterization laboratory to perform interventional procedures once a diagnosis of CAD has been established by noninvasive imaging modalities rather than using it primarily as a diagnostic facility to confirm or refute CAD. With ongoing technological advancements, noninvasive imaging plays a pre-eminent role in not only diagnosing CAD but also informing the choice of appropriate therapies, establishing prognosis, all while containing costs and providing value-based care. Multiple imaging modalities are available to evaluate patients suspected of having coronary ischemia, such as stress electrocardiography, stress echocardiography, single-photon emission computed tomography myocardial perfusion imaging, positron emission tomography, coronary computed tomography (CT) angiography, and magnetic resonance imaging. These imaging modalities can variably provide functional and anatomical delineation of coronary stenoses and help guide appropriate therapy. This review will discuss their advantages and limitations and their usage in the diagnostic pathway for patients with CAD. We also discuss newer technologies such as CT fractional flow reserve, CT angiography with perfusion, whole-heart coronary magnetic resonance angiography with perfusion, which can provide both anatomical as well as functional information in the same test, thus obviating the need for multiple diagnostic tests to obtain a comprehensive assessment of both, plaque burden and downstream ischemia. Recognizing that clinicians have a multitude of tests to choose from, we provide an underpinning of the principles of ischemia detection by these various modalities, focusing on anatomy vs physiology, the database justifying their use, their prognostic capabilities and lastly, their appropriate and judicious use in this era of patient-centered, cost-effective imaging.