Cine Steady-state Free Precession Sequences Research Articles

Deep-Learning-Based Disease Classification in Patients Undergoing Cine Cardiac MRI.

Automated approaches may allow for fast, reproducible clinical assessment of cardiovascular diseases from MRI. To develop an MRI-based deep learning (DL) disease classification algorithm to distinguish among normal subjects (NORM), patients with dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), and ischemic heart disease (IHD). Retrospective. A total of 1337 subjects (55% female), comprising normal subjects (N = 568), and patients with DCM (N = 151), HCM (N = 177), and IHD (N = 441). Balanced steady-state free precession cine sequence at 1.5/3.0 T. Bi-ventricular morphological and functional features and global and segmental left ventricular strain features were automatically extracted from short- and long-axis cine images. Variational autoencoder models were trained on the extracted features and compared against consensus disease label provided by two expert readers (13 and 14 years of experience). Adding unlabeled, normal data to the training was explored to increase specificity of NORM class. Tenfold cross-validation for model development; mean, standard deviation (SD) for measurements; classification metrics: area under the curve (AUC), confusion matrix, accuracy, specificity, precision, recall; 95% confidence intervals; Mann-Whitney U test for significance. AUCs of 0.952 for NORM, 0.881 for DCM, 0.908 for HCM, and 0.856 for IHD and overall accuracy of 0.778 were obtained, with specificity of 0.908 for the NORM class using both SAX and LAX features. Longitudinal strain features slightly improved classification metrics by 0.001 to 0.03 points, except for HCM-AUC. Differences in accuracy, metrics for NORM class and HCM-AUC were statistically significant. Cotraining using unlabeled data increased the specificity for the NORM class to 0.961. Cardiac function features automatically extracted from cine MRI have potential to be used for disease classification, especially for normal-abnormal classification. Feature analyses showed that strain features were important for disease labeling. Cotraining using unlabeled data may help to increase specificity for normal-abnormal classification. 3 TECHNICAL EFFICACY: Stage 1.

The Association of Epicardial Adipose Tissue Volume and Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy: As Assessed by Cardiac MR.

Epicardial adipose tissue (EAT) is a metabolically active visceral fat linked to cardiovascular disease. Prior studies demonstrated the predictive value of EAT volume (EATV) in atrial fibrillation (AF) among hypertrophic obstructive cardiomyopathy patients. To investigate the association between EATV and AF in hypertrophic cardiomyopathy (HCM). Retrospective. Two hundred and twenty-four HCM patients (including 79 patients with AF and 145 patients without AF, 154 men) and 80 healthy controls (54 men). 3.0 T scanner; balanced steady-state free precession (SSFP) cine sequence, gradient echo. EAT thickness was assessed in the 4-chamber and basal short-axis planes. EAT volume was calculated by outlining the epicardial border and visceral pericardium layer on short-axis cine images. Shapiro-Wilk test, Student's t test or the Mann-Whitney U test, chi-square test or Fisher's exact test, Multivariate linear regression analyses, Multivariable binary logistic regression analysis. Intraclass correlation coefficient. Significance was determined at P < 0.05. EATV and EAT volume index (EATVI) were significantly greater in HCM patients with AF than those without AF (126.6 ± 25.9 mL vs. 90.5 ± 24.5 mL, and 73.0 ± 15.9 mL/m2 vs. 51.3 ± 13.4 mL/m2). EATVI was associated with AF in multivariable linear regression analysis among HCM patients (β = 0.62). Multivariable logistic regression analysis revealed that compared to other indicators, the area under curve (AUC) of EATVI was 0.86 (cut-off, 53.9 mL/m2, 95% CI, 0.80-0.89), provided a better performance, with the sensitivity of 96.2% and specificity of 58.6%. The combined model exhibited superior association with AF presence compared to the clinical model (AUC 0.96 vs. 0.76) and the imaging model (AUC 0.96 vs. 0.93). EATVI was associated with AF. EATVI was significantly correlated with incident AF, and provided a better performance in HCM patients compared to other indicators. 3 TECHNICAL EFFICACY: Stage 2.

Incremental Prognostic Value of Left Atrial Strain in Patients With Suspected Myocarditis and Preserved Left Ventricular Ejection Fraction.

Analysis of left atrial (LA) strain and left atrioventricular coupling index (LACI) have prognostic value in cardiovascular diseases. However, the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved left ventricular ejection fraction (LVEF) is unclear. To investigate the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved LVEF in comparison with conventional MRI outcome predictors. Retrospective. One hundred sixty-five patients with clinically suspected myocarditis and preserved LVEF with available follow-up data. Steady-state free precession cine and phase-sensitive inversion recovery segmented gradient echo late gadolinium enhancement sequences at 3.0 T. Left ventricular (LV) and LA strain were evaluated using feature tracking. LACI was calculated as the ratio of LA and LV volumes at LV end-diastole. Patients were followed-up with the primary endpoint being major adverse cardiovascular events (MACE). Independent-samples t-test and Mann-Whitney U test to compare patients with and without MACE, receiver operating characteristic (ROC) curve analysis to define high/low risk groups, Kaplan-Meier survival analysis and Cox proportional hazards regression to assess prognosis. A P value of <0.05 was considered statistically significant. The associations of LV strain parameters (including global radial, circumferential, and longitudinal strain) and LACI with MACE were not significant (P = 0.511, 0.108, 0.148, and 0.847, respectively). An optimal LA conduit strain (Ԑe) cutoff value of 10.4% was identified to best classify patients into low- and high-risk groups. Only Ԑe was significantly associated with MACE in both univariable (hazards ratio [HR] 0.936, 95% confidence interval [CI] 0.884-0.991) and multivariable Cox survival analyses (HR 0.937, 95% CI 0.884-0.994). LA conduit strain has prognostic value in patients with suspected myocarditis and preserved LVEF, incremental to conventional MRI outcome predictors, whereas LACI was not associated with MACE occurrence. 3 TECHNICAL EFFICACY: Stage 2.

Evaluation of Left Ventricular Flow Kinetic Energy by Four-Dimensional Blood Flow MRI in Nondialysis Chronic Kidney Disease Patients.

Chronic kidney disease (CKD) is associated with increased, and early cardiovascular disease risk. Changes in hemodynamics within the left ventricle (LV) respond to cardiac remodeling. The LV hemodynamics in nondialysis CKD patients are not clearly understood. To use four-dimensional blood flow MRI (4D flow MRI) to explore changes in LV kinetic energy (KE) and the relationship between LV KE and LV remodeling in CKD patients. Retrospective. 98 predialysis CKD patients (Stage 3: n = 21, stage 4: n = 21, and stage 5: n = 56) and 16 age- and sex-matched healthy controls. 3.0 T/balanced steady-state free precession (SSFP) cine sequence, 4D flow MRI with a fast field echo sequence, T1 mapping with a modified Look-Locker SSFP sequence, and T2 mapping with a gradient recalled and spin echo sequence. Demographic characteristics (age, sex, height, weight, blood pressure, heart rate, aortic regurgitation, and mitral regurgitation) and laboratory data (eGFR, Creatinine, hemoglobin, ferritin, transferrin saturation, potassium, and carbon dioxide bonding capacity) were extracted from patient records. Myocardial T1, T2, LV ejection fraction, end diastolic volume (EDV), end systolic volume, LV flow components (direct flow, delayed ejection, retained inflow, and residual volume) and KE parameters (peak systolic, systolic, diastolic, peak E-wave, peak A-wave, E/A ratio, and global) were assessed. The KE parameters were normalized to EDV (KEiEDV). Parameters were compared between disease stage in CKD patients, and between CKD patients and healthy controls. Differences in clinical and imaging parameters between groups were compared using one-way ANOVA, Kruskal Walls and Mann-Whitney U tests, chi-square test, and Fisher's exact test. Pearson or Spearman's correlation coefficients and multiple linear regression analysis were used to compare the correlation between LV KE and other clinical and functional parameters. A P-value of <0.05 was considered significant. Compared with healthy controls, peak systolic (24.76 ± 5.40 μJ/mL vs. 31.86 ± 13.18 μJ/mL), systolic (11.62 ± 2.29 μJ/mL vs. 15.27 ± 5.10 μJ/mL), diastolic (7.95 ± 1.92 μJ/mL vs. 13.33 ± 5.15 μJ/mL), peak A-wave (15.95 ± 4.86 μJ/mL vs. 31.98 ± 14.51 μJ/mL), and global KEiEDV (9.40 ± 1.64 μJ/mL vs. 14.02 ± 4.14 μJ/mL) were significantly increased and the KEiEDV E/A ratio (1.16 ± 0.67 vs. 0.69 ± 0.53) was significantly decreased in CKD patients. As the CKD stage progressed, both diastolic KEiEDV (10.45 ± 4.30 μJ/mL vs. 12.28 ± 4.85 μJ/mL vs. 14.80 ± 5.06 μJ/mL) and peak E-wave KEiEDV (15.30 ± 7.06 μJ/mL vs. 14.69 ± 8.20 μJ/mL vs. 19.33 ± 8.29 μJ/mL) increased significantly. In multiple regression analysis, global KEiEDV (β* = 0.505; β* = 0.328), and proportion of direct flow (β* = -0.376; β* = -0.410) demonstrated an independent association with T1 and T2 times. 4D flow MRI-derived LV KE parameters show altered LV adaptations in CKD patients and correlate independently with T1 and T2 mapping that may represent myocardial fibrosis and edema. Stage 3.

Impact of Type 2 Diabetes Mellitus on Left Atrioventricular Coupling and Left Atrial Deformation in Patients with Essential Hypertension: An MRI Feature Tracking Study.

Hypertension (HTN) and type 2 diabetes mellitus (T2DM) are both associated with left ventricular (LV) and left atrial (LA) structural and functional abnormalities; however, the relationship between the left atrium and ventricle in this population is unclear. To identify differences between hypertensive patients with and without T2DM as the basis for further investigation the atrioventricular coupling relationship. Cross-sectional, retrospective study. 89 hypertensive patients without T2DM [HTN (T2DM-)] (age: 58.4 +/- 11.9 years, 48 male), 62 hypertensive patients with T2DM [HTN (T2DM+)] (age: 58.5 +/- 9.1 years, 32 male) and 70 matched controls (age: 55.0 +/- 9.6 years, 37 male). 2D balanced steady-state free precession cine sequence at 3.0 T. LA reservoir, conduit, and booster strain (εs, εe, and εa) and strain rate (SRs, SRe, and SRa), LV radial, circumferential and longitudinal peak strain (PS) and peak systolic strain rate and peak diastolic strain rate (PSSR and PDSR) were derived from LA and LV cine images and compared between groups. Chi-square or Fisher's exact test, one-way analysis of variance, analysis of covariance, Pearson's correlation, multivariable linear regression analysis, and intraclass correlation coefficient. A P value <0.05 was considered significant. Compared with controls, εs, εe, SRe and PS-longitudinal, PDSR-radial, and PDSR-longitudinal were significantly lower in HTN (T2DM-) group, and they were even lower in HTN (T2DM+) group than in both controls and HTN (T2DM-) group. SRs, εa, SRa, as well as PS-radial, PS-circumferential, PSSR-radial, and PSSR-circumferential were significantly lower in HTN (T2DM+) compared with controls. Multivariable regression analyses demonstrated that: T2DM and PS-circumferential and PS-longitudinal (β = -4.026, -0.486, and -0.670, respectively) were significantly associated with εs; T2DM and PDSR-radial and PDSR-circumferential were significantly associated with εe (β = -3.406, -3.352, and -6.290, respectively); T2DM and PDSR-radial were significantly associated with SRe (β = 0.371 and 0.270, respectively); T2DM and PDSR-longitudinal were significantly associated with εa (β = -1.831 and 5.215, respectively); and PDSR-longitudinal was significantly associated with SRa (β = 1.07). In hypertensive patients, there was severer LA dysfunction in those with coexisting T2DM, which may be associated with more severe LV dysfunction and suggests adverse atrioventricular coupling. 3. Stage 3.

Comparative analysis of left ventricle function and deformation imaging in short and long axis plane in cardiac magnetic resonance imaging.

Advancements in cardiac imaging have revolutionized our understanding of ventricular contraction. While ejection fraction (EF) is still the gold standard parameter to assess left ventricle (LV) function, strain imaging (SI) has provided valuable insights into ventricular mechanics. The lack of an integrative method including SI parameters in a single, validated formula may limit its use. Our aim was to compare different methods for evaluating global circumferential strain (GCS) and their relationship with global longitudinal strain (GLS) and EF in CMR and how the different evaluations fit in the theoretical relationship between EF and global strain. Retrospective monocenter study. Inclusion of every patient who underwent a CMR during a 15 months period with various clinical indication (congenital heart defect, myocarditis, cardiomyopathy). A minimum of three LV long-axis planes and a stack of short-axis slices covering the LV using classical steady-state free precession cine sequences. A single assessment of GLS on long axis (LAX) slices and a double assessment of GCS and EF with both short axis (SAX) and LAX slices were made by a single experienced CMR investigator. GCS-SAX and GCS-LAX were correlated (r = 0.77, P < 0.001) without being interchangeable with a high reproducibility for GCS, GLS and EF. EF calculated from LAX images showed an overestimation compared to EF derived from SAX images of 7%. The correlation between calculated EF and theoretical EF derived from SI was high (r = 0.88 with EF-SAX, 0.95 with EF-LAX). This study highlights the need to integrate strain imaging techniques into clinical by incorporating strain parameters into EF calculations, because it gives a deeper understanding of cardiac mechanics.

Left ventricular function assessment including or excluding trabeculations in left ventricular non-compaction, a preliminary case-control cardiac magnetic resonance study.

Functional assessment of compact myocardium and hypertrabeculations in left ventricular non-compaction (LVNC) is underestimated with regards to the morphological spectrum of disease. We aimed to assess whether measuring concurrently left ventricular (LV) volume, mass and ejection fraction (LVEF) with and without trabeculation inclusion on cine magnetic resonance (cineMR) could help diagnose patients with LVNC by comparison to normal individuals with an excess of myocardial trabeculations. This retrospective single center magnetic resonance imaging study (Bichat University Hospital) of 67 consecutive patients with echocardiographic hypertrabeculations seen at echocardiography between March 2011 and October 2018 included 30 patients with known LVNC and 16 control subjects with simple hypertrabeculations (non-compact/compact (NC/C) ratio between 1.8 and 2.2, trabeculations involving 10% to 17% of the left ventricle) using steady-state free precession (SSFP) cine sequences in the standard views. LV volumes, mass and LVEF were measured with and without trabeculation inclusion using CVI42 software. Follow-up was studied in 20 patients and 14 controls. Functional parameters were compared using Student's paired t-test. Pearson product moment correlation coefficients were calculated. Bland-Altman analysis determined the inter- and intra-reader functional data reproducibility. When excluding the trabeculations (i.e. non-compacted myocardium) from measurements, LVEF was within normal ranges both in patients and controls, while it increased by 9.8%±1.6% in LVNC and decreased by 10.9%±1.4% in controls when trabeculae were included in the endocardial contours (P<0.0001). The overall myocardial mass remained stable according to the diastolic or systolic phase in LVNC whereas it significantly decreased in controls. Depending whether trabeculations were included or not, LVEF measurements were significantly different between patients with LVNC and controls. These distinctive measurements might be used as an adjunctive clinical tool to help confirm the diagnosis of LVNC.

Aligning Multi-Sequence CMR Towards Fully Automated Myocardial Pathology Segmentation.

Myocardial pathology segmentation (MyoPS) is critical for the risk stratification and treatment planning of myocardial infarction (MI). Multi-sequence cardiac magnetic resonance (MS-CMR) images can provide valuable information. For instance, balanced steady-state free precession cine sequences present clear anatomical boundaries, while late gadolinium enhancement and T2-weighted CMR sequences visualize myocardial scar and edema of MI, respectively. Existing methods usually fuse anatomical and pathological information from different CMR sequences for MyoPS, but assume that these images have been spatially aligned. However, MS-CMR images are usually unaligned due to the respiratory motions in clinical practices, which poses additional challenges for MyoPS. This work presents an automatic MyoPS framework for unaligned MS-CMR images. Specifically, we design a combined computing model for simultaneous image registration and information fusion, which aggregates multi-sequence features into a common space to extract anatomical structures (i.e., myocardium). Consequently, we can highlight the informative regions in the common space via the extracted myocardium to improve MyoPS performance, considering the spatial relationship between myocardial pathologies and myocardium. Experiments on a private MS-CMR dataset and a public dataset from the MYOPS2020 challenge show that our framework could achieve promising performance for fully automatic MyoPS.

MRI Quantification of Left Atrial Circumferential Strain in Mitral Regurgitation: A Feasibility and Reproducibility Study.

MRI-derived left atrial (LA) longitudinal strain has been shown to be a marker for mitral regurgitation, but the utility of LA circumferential strain remains unclear. To assess feasibility and reproducibility of LA circumferential strain, identify changes in mitral regurgitation patients compared to healthy volunteers, and determine strain's association with mitral regurgitation severity and cardiac function. Retrospective. 52 mitral regurgitation patients, 12 healthy volunteers. Steady-state free precession cine and 2D phase contrast sequences at 1.5T. Peak LA circumferential strain was computed in each of three short-axis slices (superior, mid, and inferior) and longitudinal strain computed from long-axis slices using MRI feature-tracking software. Strain test-retest reproducibility was determined from two repeat studies in healthy volunteers. LA circumferential strain test-retest reproducibility was assessed by intra-class correlation coefficient (ICC). Strain was compared between cohorts using Student's t-test or Mann-Whitney U. Mitral regurgitation severity association with strain and LV function was assessed using Spearman correlation and multivariable regression. Significance was defined as P < 0.05. LA circumferential strain assessment was feasible in all subjects with moderate reproducibility in the superior (ICC = 0.74), mid LA (ICC = 0.71), and inferior LA (ICC = 0.63). In mitral regurgitation patients, LA circumferential strain was significantly lower in the superior (11.86% [6.5%,19.2%] vs. 18.73% ± 6.7%) and mid LA slices (18.41% ± 9.5% vs. 28.7% ± 10.4%) compared to healthy volunteers. Mitral regurgitation severity significantly associated with mid LA circumferential strain (β = -0.03) and LAV significantly associated with superior LA circumferential strain (β = -2.09), both independent of LA longitudinal strain and CO. LA circumferential strain assessment is feasible with moderate reproducibility. Compared to healthy volunteers, patients had significantly lower LA circumferential strain. Mitral regurgitation severity and LAV were significantly associated with LA circumferential strain independent of LA longitudinal strain. 3 TECHNICAL EFFICACY: Stage 2.

Territorial Post-Revascularization Remodeling of Chronic Coronary Syndromes: Cardiac Magnetic Resonance Feature Tracking Study.

MRI feature-tracking (MRI-FT) can accurately assess ventricular myocardial deformation and regional function and may be a better predictor of mortality than ejection fraction and infarct extension. However, role of MRI-FT in assessing coronary revascularization is unclear. To assess coronary revascularization effect on territorial left ventricle (LV) function of chronic coronary syndrome (CCS) patients by MRI-FT. Prospective. 50 CCS patients (age: 62.22 ± 8.70 years) scheduled for elective percutaneous coronary intervention (PCI), and 30 healthy controls (age: 35.33 ± 11.57 years). 1.5T with balanced steady-state free precession cine sequence. Global and segmental peak systolic longitudinal, circumferential, and radial myocardial strains were quantified in both patient and healthy control groups by an experienced operator using dedicated software. Patients were studied both pre-PCI and 6-month post-PCI and LV territorial myocardial strain values were calculated by averaging the segmental values of each revascularized territory. Student's t-test, paired t-test, Mann Whitney test, and Wilcoxon signed ranks test. Significance was judged at the 5% level. Territorial longitudinal strain showed significant 6-month post-PCI improvement in the left anterior descending (LAD) and right coronary artery (RCA) territories, but there was not in the left circumflex (LCX) territory (LAD: mean - 11.41% ± 3.45% pre, -13.01% ± 3.53% post; RCA: mean - 11.11% ± 2.65% pre, -13.25% ± 2.81% post; and LCX: mean - 15.43% ± 3.97% pre, -16.17% ± 4.38% post, P = 0.215). Territorial circumferential strain showed significant post-PCI improvement in all revascularized territories (LAD: mean - 13.73% ± 6.56% pre, -16.98% ± 6.01% post; LCX: mean - 13.23% ± 4.23% pre, -16.34% ± 3.45% post; and RCA: mean - 11.24% ± 3.36% pre, -13.80% ± 3.51% post). Territorial radial strain showed no significant post-PCI improvement (LAD: mean 22.73% ± 12.38% pre, 21.79% ± 11.55% post, P = 0.541; LCX: mean 27.73% ± 7.95% pre, 29.0% ± 7.25% post, P = 0.264; and RCA: mean 36.68% ± 11.10% pre, 31.75% ± 10.95% post, P = 0.208). Territorial LV systolic function was significantly improved by coronary revascularization in CCS patients. 1 TECHNICAL EFFICACY: Stage 4.

Diastology with Cardiac MRI: A Practical Guide.

Diastolic filling of the ventricle is a complex interplay of volume and pressure, contingent on active energy-dependent myocardial relaxation and myocardial stiffness. Abnormal diastolic function is the hallmark of the clinical entity of heart failure with preserved ejection fraction (HFpEF), which is now the dominant type of heart failure and is associated with significant morbidity and mortality. Although echocardiography is the current first-line imaging modality used in evaluation of diastolic function, cardiac MRI (CMR) is emerging as an important technique. The principal role of CMR is to categorize the cause of diastolic dysfunction (DD) and distinguish other entities that manifest similarly to HFpEF, particularly infiltrative and pericardial disorders. CMR also provides prognostic information and risk stratification based on late gadolinium enhancement and parametric mapping techniques. Advances in hardware, sequences, and postprocessing software now enable CMR to diagnose and grade DD accurately, a role traditionally assigned to echocardiography. Two-dimensional or four-dimensional velocity-encoded phase-contrast sequences can measure flow and velocities at the mitral inflow, mitral annulus, and pulmonary veins to provide diastolic functional metrics analogous to those at echocardiography. The commonly used cine steady-state free-precession sequence can provide clues to DD including left ventricular mass, left ventricular filling curves, and left atrial size and function. MR strain imaging provides information on myocardial mechanics that further aids in diagnosis and prognosis of diastolic function. Research sequences such as MR elastography and MR spectroscopy can help evaluate myocardial stiffness and metabolism, respectively, providing additional insights on diastolic function. The authors review the physiology of diastolic function, mechanics of diastolic heart failure, and CMR techniques in the evaluation of diastolic function. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Glycemic Status and Myocardial Strain by Cardiac MRI in Patients With ST-Segment Elevation Myocardial Infarction.

It is uncertain how various degree of glycemic status affect left ventricular (LV) myocardial strain in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI). To investigate the relationship of glycemic status and myocardial strain in STEMI patients. Prospective cohort study. 282 STEMI patients with cardiac magnetic resonance imaging 5 ± 2 days post-PPCI. Patients were divided into three groups based on the level of glycated hemoglobin A1c (HbA1c) (group 1: HbA1c < 5.7%; group 2: 5.7% ≤ HbA1c < 6.5%; group 3: HbA1c ≥ 6.5%). 3.0-T; late gadolinium enhancement, balanced steady-state free precession cine sequence, black blood fat-suppressed T2-weighted. LV function, myocardial strain, and infarct characteristics (infarct size, microvascular obstruction, and intramyocardial hemorrhage) were compared among the three groups by one-way analysis of variance (ANOVA) or Wilcoxon rank sum test. Intraobserver and interobserver reproducibility of LV myocardial strain was evaluated. ANOVA or Wilcoxon rank sum test, Pearson chi-square or Fisher's exact test, Spearman's correlation analyses and multivariable linear regression analysis. A two-tailed P value <0.05 was considered statistically significant. Infarct characteristics were similar among the three groups (P = 0.934, P = 0.097, P = 0.533, respectively). Patients with HbA1c ≥ 6.5% had decreased LV myocardial strain compared with HbA1c 5.7%-6.4%, as evidenced by global radial (GRS), global circumferential (GCS), and global longitudinal (GLS) strain. However, no significant differences in myocardial strain were observed between patients with HbA1c 5.7%-6.4% and HbA1c < 5.7% (P = 0.716; P = 0.294; P = 0.883, respectively). After adjustment for confounders, HbA1c as a continuous variable (beta coefficient [β] = -0.676; β = 0.172; β = 0.205, respectively) and HbA1c ≥ 6.5% (β = -3.682; β = 0.552; β = 0.681, respectively) were both independently associated with decreased GRS, GCS, and GLS. Patients with uncontrolled blood glucose (categorized in group HbA1c ≥ 6.5%) had worse myocardial strain. The level of HbA1c appeared to be independently associated with decreased myocardial strain in STEMI patients. 2 TECHNICAL EFFICACY STAGE: 2.

Compressed sensing cine imaging with higher temporal resolution for analysis of left atrial strain and strain rate by cardiac magnetic resonance feature tracking.

Cardiac magnetic resonance (CMR) feature tracking (FT) is more widely used in the measurement of left atrial (LA) strain and strain rate (SR). However, in recent years, researchers have attempted to improve the low temporal resolution of CMR-FT to better capture the subtle deformations of the myocardium. The technique of compressed sensing (CS) has been applied clinically, reducing scan time while increasing temporal resolution. The purpose of this study was to explore the effect of the increased temporal resolution of CS cine sequences on the analysis of LA longitudinal strain and SR. Twenty-nine healthy subjects were included in the study. They underwent CMR with a reference steady-state free precession cine sequence of conventional temporal resolution (standard SSFP sequence), a cine sequence of higher temporal resolution (HT sequence), and an HT cine sequence with CS (CS HT sequence) (temporal resolution: 22.1-44.3/24.9-47.1ms, 11.1-19.4ms, and 8.3-19.4ms, respectively). The standard SSFP sequence, HT sequence, and CS HT sequence were acquired in all subjects during the same scanning session. LA longitudinal strain and SR, reflecting LA reservoir, conduit, and contraction booster-pump function, were measured by CMR-FT and compared among the three sequences. The measurements of LASR reservoir, conduit, and booster-pump were significantly higher on the HT and CS HT sequences than on the standard SSFP sequence. The standard SSFP sequence was correlated significantly with the HT and CS HT sequences in terms of LA strain and SR analysis, respectively. The LA strain and SR measurements also showed excellent agreement between the HT and CS HT sequences. Higher temporal resolution led to significantly higher measured LASR values in CMR-FT. Furthermore, the addition of CS reduced scan time and did not affect LA longitudinal strain or SR analysis.

Magnetic resonance imaging reference values for cardiac morphology, function and tissue composition in adolescents.

Cardiovascular magnetic resonance (CMR) is a precise tool for the assessment of cardiac anatomy, function, and tissue composition. However, studies providing CMR reference values in adolescence are scarce. We aim to provide sex-specific CMR reference values for biventricular and atrial dimensions and function and myocardial relaxation times in this population. Adolescents aged 15-18 years with no known cardiovascular disease underwent a non-contrast 3-T CMR scan between March 2021 and October 2021. The imaging protocol included a cine steady-state free-precession sequence for the analysis of chamber size and function, as well as T2-GraSE and native MOLLI T1-mapping for the characterization of myocardial tissue. CMR scans were performed in 123 adolescents (mean age 16±0.5 years, 52% girls). Mean left and right ventricular end-diastolic indexed volumes were higher in boys than in girls (91.7±11.6 vs 78.1±8.3ml/m2, p<0.001; and 101.3±14.1 vs 84.1±10.5ml/m2, p<0.001), as was the indexed left ventricular mass (48.5±9.6 vs 36.6±6.0g/m2, p<0.001). Left ventricular ejection fraction showed no significant difference by sex (62.2±4.1 vs 62.8±4.2%, p=0.412), whereas right ventricular ejection fraction trended slightly lower in boys (55.4±4.7 vs. 56.8±4.4%, p=0.085). Indexed atrial size and function parameters did not differ significantly between sexes. Global myocardial native T1 relaxation time was lower in boys than in girls (1215±23 vs 1252±28ms, p<0.001), whereas global myocardial T2 relaxation time did not differ by sex (44.4±2.0 vs 44.1±2.4ms, p=0.384). Sex-stratified comprehensive percentile tables are provided for most relevant cardiac parameters. This cross-sectional study provides overall and sex-stratified CMR reference values for cardiac dimensions and function, and myocardial tissue properties, in adolescents. This information is useful for clinical practice and may help in the differential diagnosis of cardiac diseases, such as cardiomyopathies and myocarditis, in this population. Instituto de Salud Carlos III (PI19/01704).

Cardiac magnetic resonance imaging derived reference values for ventricular anatomy and function and myocardial tissue characterization in adolescents: the EnIGMA study

Abstract Introduction Cardiac magnetic resonance (CMR) imaging is a precise tool for the assessment of cardiac anatomy and function. However, studies providing reference values for CMR parameters, including myocardial tissue properties, in healthy adolescents are scarce. Purpose To provide CMR derived reference values for biventricular mass, volumes and function measured by cine steady-state free-precession (SSFP) sequences and myocardial tissue relaxation properties as measured by native T1- and T2-mapping sequences in healthy adolescents. Methods A comprehensive non-contrast CMR study was performed in healthy adolescents aged 15 to 18 years enrolled in the “Early ImaginG Markers of unhealthy lifestyles in Adolescents” (EnIGMA) project using a 3-Tesla CMR scanner between March 2021 and October 2021. The imaging protocol included a cine SSFP to provide high-quality images for chamber size and function analysis, and a T2-GraSE mapping and native T1-mapping sequences (MOLLI Scheme 5 (3) 3) to provide precise myocardial relaxation time properties. Images were analyzed by experienced observers using the Cardiac Analysis tool available at IntelliSpace Portal following a standard protocol. In cine SSFP sequences, right and left ventricles were manually contoured for end-diastolic and end-systolic phases in the short-axis orientation, respectively (Figure 1A, B). Native T1 and T2 maps were analyzed in a mid-ventricular short axis slice and summarized values per individual were determined (Figure 1C, D). Student's t-tests were used for between-gender comparisons. Results CMR scans were performed in 123 adolescents (63 girls, 51.2%) with a mean age of 16.0 years (standard deviation (SD)=0.5), mean body mass index of 21.4 (SD=3.2) kg/m2, mean body surface area of 1.69 (SD=0.16) m2, and mean heart rate during CMR acquisitions of 69 (SD=11) beats/minute. Reference percentiles (P) 3, 10, 25, 50, 75, 90 and 97 for the different parameters analyzed by gender are provided in Figure 2. Mean left and right ventricular end-diastolic indexed volumes were higher in boys than in girls (91.5 vs 78.1 ml/m2, p&amp;lt;0.01; and 101.1 vs 84.2 ml/m2, p&amp;lt;0.01), as well as the indexed cardiac mass (48.4 vs 36.4 g/m2, p&amp;lt;0.01). Left ventricular ejection fraction (LVEF) was similar in boys and girls (62.0 vs. 62.9%, p=0.23), whereas right ventricular ejection fraction was slightly lower in boys than in girls (55.3 vs. 57.1%, p=0.03). Mean myocardial native T1 relaxation time was 1253 (SD=28) ms in girls and 1215 (SD=23) ms in boys (p&amp;lt;0.01), whereas mean myocardial T2 relaxation time was 44.1 (SD=2.3) ms and 44.4 (SD=2.0) ms in girls and boys, respectively (p=0.46). Conclusion This study provided CMR derived reference values for biventricular anatomy, function, and myocardial tissue properties, in healthy adolescents aged 15 to 18 years. This information may be useful for the differential diagnosis of cardiac diseases, such as cardiomyopathies and myocarditis, in adolescent population. Funding Acknowledgement Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Instituto de Salud Carlos III (ISCIII)-Fondo de Investigaciόn SanitariaEuropean Regional Development Fund/European Social Fund (“A way to make Europe”/“Investing in your future”)

Ventricular-arterial coupling predicts outcomes in adults with a systemic right ventricle

Abstract Background Patients with a systemic right ventricle (SRV) and biventricular circulation experience high incidence of cardiovascular morbidities and decreased survival [1]. Non-invasive measures of subclinical ventricular dysfunction are needed to appropriately identify patients at increased risk for adverse outcomes. Ventricular-arterial coupling (VAC), the ratio between the effective arterial elastance (Ea) and ventricular end-systolic elastance (Ees), may predict clinical outcomes in patients with SRV [2]. Objectives To assess VAC in adults with SRV and evaluate its correlation with clinical outcomes. Methods Consecutive cardiovascular magnetic resonance (CMR) examinations of adults with D-loop transposition of great arteries (TGA) after atrial switch operation and L-loop TGA performed at Boston Children's Hospital between 2005 and 2019 were analyzed. VAC was calculated as Ea/Ees (Ea = mean arterial blood pressure (MBP)/ventricular stroke volume; Ees = MBP/end-systolic volume). Global myocardial strain was measured by feature tracking analysis on cine steady-state free precession sequences. Cox proportional hazards regression analysis was performed to assess the association of SRV functional parameters with clinical outcomes. The analysis was adjusted for age, sex, and body mass index. The primary outcome was defined as a composite of death, cardiovascular arrest, hospitalizations for heart failure (HF); the secondary outcome as atrial arrhythmias; the tertiary outcome included other causes of cardiovascular hospitalizations (percutaneous or surgical interventions, device implantation, other cardiovascular disease). Cumulative incidence of the study outcomes was estimated using Kaplan-Meier method. Results One hundred sixty-seven adults (mean age 32±10 years, 59% men) with SRV were analyzed. Patients with HF (n=48, 29%) had higher VAC values as compared to those without HF (1.4±0.8 vs. 1.1±0.5, p=0.01). Over a mean follow-up of 6.5±4.2 years, 15 over 139 patients (11%) experienced the primary outcome with an incidence rate of 1.7 per 100 patient-years (95% confidence interval (CI), 1.04–2.85). Higher VAC values were significantly associated with an increased risk of the primary outcome (p for trend = 0.01, Figure 1). VAC was the only functional parameter associated with the primary outcome (hazard ratio (HR) 1.99, 95% CI: 1.06–3.73, p=0.031), secondary outcome (HR 2.33, 95% CI: 1.12–4.82, p=0.023) and tertiary outcome (HR 1.63, 95% CI: 1.09–2.44, p=0.018) in the adjusted analysis (Table 1). Ejection fraction (EF) was not associated with the study outcomes in the adjusted analysis (p&amp;gt;0.05, Table 1) whereas global circumferential and radial strain showed an association limited to the tertiary endpoint (p=0.004, Table 1). Conclusions CMR-derived VAC is associated with adverse outcomes in SRV patients and may improve risk stratification of this unique population. Funding Acknowledgement Type of funding sources: None.

Non-contrast free-breathing whole-heart 3D cine cardiovascular magnetic resonance with a novel 3D radial leaf trajectory

PurposeTo develop and validate a non-contrast free-breathing whole-heart 3D cine steady-state free precession (SSFP) sequence with a novel 3D radial leaf trajectory. MethodsWe used a respiratory navigator to trigger acquisition of 3D cine data at end-expiration to minimize respiratory motion in our 3D cine SSFP sequence. We developed a novel 3D radial leaf trajectory to reduce gradient jumps and associated eddy-current artifacts. We then reconstructed the 3D cine images with a resolution of 2.0mm3 using an iterative nonlinear optimization algorithm. Prospective validation was performed by comparing ventricular volumetric measurements from a conventional breath-hold 2D cine ventricular short-axis stack against the non-contrast free-breathing whole-heart 3D cine dataset in each patient (n = 13). ResultsAll 3D cine SSFP acquisitions were successful and mean scan time was 07:09 ± 01:31 min. End-diastolic ventricular volumes for left ventricle (LV) and right ventricle (RV) measured from the 3D datasets were smaller than those from 2D (LV: 159.99 ± 42.99 vs. 173.16 ± 47.42; RV: 180.35 ± 46.08 vs. 193.13 ± 49.38; p-value≤0.044; bias<8%), whereas ventricular end-systolic volumes were more comparable (LV: 79.12 ± 26.78 vs. 78.46 ± 25.35; RV: 97.18 ± 32.35 vs. 102.42 ± 32.53; p-value≥0.190, bias<6%). The 3D cine data had a lower subjective image quality score. ConclusionOur non-contrast free-breathing whole-heart 3D cine sequence with novel leaf trajectory was robust and yielded smaller ventricular end-diastolic volumes compared to 2D cine imaging. It has the potential to make examinations easier and more comfortable for patients.

Oxygenation-sensitive Cardiac MRI with Vasoactive Breathing Maneuvers for the Non-invasive Assessment of Coronary Microvascular Dysfunction.

Oxygenation-sensitive cardiac magnetic resonance imaging (OS-CMR) is a diagnostic technique that uses the inherent paramagnetic properties of deoxyhemoglobin as an endogenous source of tissue contrast. Used in combination with standardized vasoactive breathing maneuvers (hyperventilation and apnea) as a potent non-pharmacologic vasomotor stimulus, OS-CMR can monitor changes in myocardial oxygenation. Quantifying such changes during the cardiac cycle and throughout vasoactive maneuvers can provide markers for coronary macro- and microvascular function and thereby circumvent the need for any extrinsic, intravenous contrast or pharmacologic stress agents. OS-CMR uses the well-known sensitivity of T2*-weighted images to blood oxygenation. Oxygenation-sensitive images can be acquired on any cardiac MRI scanner using a modified standard clinical steady-state free precession (SSFP) cine sequence, making this technique vendor-agnostic and easily implemented. As a vasoactive breathing maneuver, we apply a 4 min breathing protocol of 120 s of free breathing, 60 s of paced hyperventilation, followed by an expiratory breath-hold of at least 30 s. The regional and global response of myocardial tissue oxygenation to this maneuver can be assessed by tracking the signal intensity change. The change over the initial 30 s of the post-hyperventilation breath-hold, referred to as the breathing-induced myocardial oxygenation reserve (B-MORE) has been studied in healthy people and various pathologies. A detailed protocol for performing oxygen-sensitive CMR scans with vasoactive maneuvers is provided. As demonstrated in patients with microvascular dysfunction in yet incompletely understood conditions, such as inducible ischemia with no obstructive coronary artery stenosis (INOCA), heart failure with preserved ejection fraction (HFpEF), or microvascular dysfunction after heart transplantation, this approach provides unique, clinically important, and complementary information on coronary vascular function.

The Role of MR Assessments of Cardiac Morphology, Function, and Tissue Characteristics on Exercise Capacity in Well-Functioning Older Adults.

The relationship between resting cardiac indices and exercise capacity in older adults was still not well understood. New developments in cardiac magnetic resonance imaging (MRI) enable a much fuller assessment of cardiac characteristics. To assess the association between exercise capacity and specific aspects of resting cardiac structure, function, and tissue. Cross-sectional study. A total of 112 well-functioning older adults (mean age 69 years, 52 men). All participants underwent 3.0 T MRI, using scan protocols including balanced steady-state free precession cine sequence, modified look-locker inversion recovery, and T2-prepared single-shot balanced steady-state free precession. Demographic and geriatric characteristics were collected. Blood samples were assayed for lipid and glucose related biomarkers. All participants performed a symptom-limited cardiopulmonary exercise test to achieve peakVO2 . Cardiac MRI parameters were measured with semi-automatic software by S.Y., an 18-year experienced radiologist. Demographic, geriatric characteristics and MR measurements were compared among quartiles of peakVO2, with different methods according to the data type. Spearman's partial correlation and least absolute shrinkage selection operator regression were performed to select significant MR features associated with peakVO2 . Mediation effect analysis was conducted to test any indirect connection between age and peakVO2 . A two-sided P value of <0.05 was defined statistical significance. Epicardial fat volume, left atrial volume indexed to height, right ventricular end-systolic volume indexed to body surface area and global circumferential strain (GCS) were correlated with peakVO2 (regression coefficients were -0.040, -0.093, 0.127, and 0.408, respectively). Mediation analysis showed that the total effect of peakVO2 change was 43.6% from the change of age. The proportion of indirect effect from epicardial fat volume and GCS were 11.8% and 15.1% in total effect, respectively. PeakVO2 was associated with epicardial fat volume, left atrial volume, right ventricular volume and GCS of left ventricle. 4 TECHNICAL EFFICACY: Stage 5.

Sex Effect in the Decision to Perform Invasive Coronary Angiography in Patients With Chronic Coronary Syndrome After Undergoing Vasodilator Stress MRI.

Stress cardiac MRI permits comprehensive evaluation of patients with known or suspected chronic coronary syndromes (CCS). The impact of sex on the use of invasive cardiac angiography (ICA) after vasodilator stress cardiac MRI is unclear. To evaluate the impact of sex on ICA use after vasodilator stress cardiac MRI. Retrospective. A total of 6229 consecutive patients (age [mean ± standard deviation] 65.2 ± 11.5 years, 38.1% women). A 5-T; a steady-state free-precession cine sequence; stress first-pass perfusion imaging; late enhancement imaging. Patients underwent vasodilator stress cardiac MRI for known or suspected CCS. The ischemic burden (at stress first-pass perfusion imaging) was computed (17-segment model). Multivariate logistic regression was used to evaluate the potential differential association between ischemic burden and use of cardiac MRI-related ICA across sex. A total of 1109 (17.8%) patients were referred to ICA, among which there were significantly more men (762, 19.7%) than women (347, 14.6%). Overall, after multivariate adjustment, female sex was not associated with lower use of ICA (odds ratio [OR]=0.99; confidence interval [CI] 95%: 0.84-1.18, P=0.934). However, significant sex differences were detected across ischemic burden. Whereas women with nonischemic vasodilator stress cardiac MRI (0 ischemic segments) were less commonly submitted to ICA (OR=0.49; CI 95%: 0.35-0.69) in patients with ischemia (>1 ischemic segment), adjusted use of ICA was more frequent in women than men (OR=1.27; CI 95%: 1.1-1.5). In patients with known or suspected CCS submitted to undergo vasodilator stress cardiac MRI, cardiac MRI-related ICA may be overused in men without ischemia. Furthermore, ICA referral in patients with negative ischemia resulted in greater odds of revascularization in men. 3 TECHNICAL EFFICACY: Stage 5.