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Background: End-stage renal disease (ESRD) patients are at high cardiovascular risk, and myocardial fibrosis (MF) accounts for most of their cardiac events. The purpose of this study is to investigate the prognostic value and risk stratification of MF as measured by extracellular volume (ECV) on cardiac magnetic resonance (CMR) for heart failure (HF) in patients with hemodialysis-dependent ESRD.Methods: Sixty-six hemodialysis ESRD patients and 25 matched healthy volunteers were prospectively enrolled and underwent CMR to quantify multiple parameters of MF by T1 mapping and late gadolinium enhancement (LGE). All ESRD patients were followed up for 11-30 months, and the end-point met the 2016 ESC guidelines for the definition of HF.Results: Over a median follow-up of 18 months (range 11-30 months), there were 26 (39.39%) guideline-diagnosed HF patients in the entire cohort of ESRD subjects. The native T1 value was elongated, and ECV was enlarged in the HF cohort relative to the non-HF cohort and normal controls (native T1, 1360.10 ± 50.14 ms, 1319.39 ± 55.44 ms and 1276.35 ± 56.56 ms; ECV, 35.42 ± 4.42%, 31.85 ± 3.01% and 26.97 ± 1.87%; all p<0.05). In the cardiac strain analysis, ECV was significantly correlated with global radial strain (GRS) (r = - 0.501, p = 0.009), global circumferential strain (GCS) (r = 0.553, p = 0.005) and global longitudinal strain (GLS) (r = 0.507, p = 0.008) in ESRD patients with HF. Cox proportional hazard regression models revealed that ECV (hazard ratio [HR] = 1.160, 95% confidence interval: 1.022 to 1.318, p = 0.022) was the only independent predictor of HF in ESRD patients. It also had a higher diagnostic accuracy for detecting MF (area under the curve [AUC] = 0.936; 95% confidence interval: 0.864 to 0.976) than native T1 and post T1 (all p ≤ 0.002). Kaplan-Meier analysis revealed that the high-ECV group had a shorter median overall survival time than the low-ECV group (18 months vs. 20 months, log-rank p = 0.046) and that ESRD patients with high ECV were more likely to have HF.Conclusions: Myocardial fibrosis quantification by ECV on CMR T1 mapping was shown to be an independent risk factor of heart failure, providing incremental prognostic value and risk stratification for cardiac events in ESRD patients.Trial Registration: Chinese Clinical Trial Registry ChiCTR-DND-17012976, 13/12/2017, Retrospectively registered. [ABSTRACT FROM AUTHOR]

Background: Both acute and chronic myocardial infarction (AMI and CMI, respectively) exhibit delayed enhancement; however, clinical decision-making processes frequently require the differentiation of these two types of myocardial injury.Purpose: To investigate the reliability of AMI and CMI characterization using native T1 mapping and its feasibility for discriminating AMI from CMI.Study Type: Case-control.Animal Model: The study cohort comprised 12 AMI (mean post-MI, 3.75 ± 1.29 days) and 15 CMI (mean post-MI, 39.53 ± 6.10 days) Bama mini-pigs.Field Strength/sequence: Balanced steady-state free precession (bSSFP), segmented-turbo-FLASH-PSIR, and modified Look-Locker inversion recovery (MOLLI) sequences at 3.0T.Assessment: The infarct sizes were compared on matching short-axis slices of late-gadolinium-enhanced (LGE) images and T1 maps by two experienced radiologists.Statistical Tests: The infarct sizes were compared on matching short-axis slices of LGE images and T1 maps, and agreement was determined using linear regression and Bland-Altman analyses. The native T1 values were compared between AMI and CMI models (independent sample t-test). The intraclass correlation coefficient was used to assess inter- and intraobserver variability.Results: Measured infarct sizes did not differ between native T1 mapping and LGE images (AMI: P = 0.913; CMI: P = 0.233), and good agreement was observed between the two techniques (AMI: bias, -3.38 ± 19.38%; R2  = 0.96; CMI: bias, -10.55 ± 10.90%; R2  = 0.90). However, the native infarction myocardium T1 values and the T1 signal intensity ratio of infarct and remote myocardium (T1 SI ratio) did not differ significantly between AMI and CMI (P = 0.173).Data Conclusion: Noncontrast native T1 mapping can accurately determine acute and chronic infarct areas as well as conventional LGE imaging; however, it cannot distinguish acute from chronic MI.Level Of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1406-1414. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to assess the extracellular volume fraction (ECV) in type 2 diabetes mellitus (T2DM) patients with different level of hemoglobin A1c (HbA1c) by cardiac magnetic resonance (CMR), and the ability of HbA1c to predict myocardial fibrosis.Methods: In total, 80 T2DM patients and 20 age- and sex-matched controls were prospective enrolled and underwent CMR to obtain ECV value and LV function parameters. We divided all patients into a group of HbA1c < 7.0% and a group of HbA1c ≥ 7.0%.Results: In the higher HbA1c group the ECV value (all p < 0.001) was higher than both lower HbA1c group (36.23% vs. 32.19%, p < 0.001) and controls (36.23% vs. 29.73%, p < 0.001). HbA1c was positively associated (β = 0.36, p = 0.004) with ECV, and it was also an independent predictor of myocardial fibrosis (OR = 2.00, P = 0.014). The ROC analysis showed that 7.1% was the optimal cutoff value of HbA1c that predicted the risk of myocardial fibrosis with high diagnostic accuracy (area under the curve = 0.78).Conclusion: T1 mapping provided myocardial fibrosis information in T2DM patients. HbA1c is positively correlated with myocardial fibrosis and can be an independently predictor of myocardial fibrosis, which may be helpful for the clinical decision-making of blood glucose control. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to clarify the feasibility of myocardial strain using cardiovascular magnetic resonance (CMR) for the evaluation of left ventricular (LV) deformation in patients with Ebstein's anomaly (EA).Materials and Methods: We recruited 32 patients with EA and 30 controls for CMR examination and measured LV function, dimension and tissue tracking parameters (the global and regional radial, circumferential and longitudinal peak strain), together with the right ventricle (RV) dimension. LV strain parameters were compared among the controls, patients with preserved LV ejection fraction (LVEF; ≥55%), and patients with reduced LVEF (<55%). Pearson's correlation was used to evaluate relationships between tissue tracking parameters with the RVEDD/LVEDD index and LVEF. An ROC analysis was also performed to determine whether the cut-off values for PS could be used to differentiate LV dysfunction between patients with EA and controls. The intraclass correlation coefficient (ICC) was used to assess the inter- and intra-observer variability.Results: The global strain parameters all decreased significantly in the EA group compared with the control group (all P<0.05). Furthermore, the global radial and circumferential peak strain (PS) were obviously even lower in the reduced LVEF group than the strain measured in preserved LVEF groups (28.64% vs. 37.39%, p<0.05; and -8.20% vs. -17.89%; p<0.05; respectively). The regional strain abnormalities in EA patients were mainly involved in basal and middle segments. The results also demonstrated a significant correlation between the ratio of the RV end-diastolic dimension to the LV end-diastolic dimension (RVEDD/LVEDD index) with the global circumferential PS (r=0.508) and the longitudinal PS (r=0.474), as well as a good correlation between radial PS and LVEF (r=0.465). The ICCs for intra- and inter-observer variability were 0.797-0.904 and 0.701-0.896.Conclusions: LV strain serves an earlier and more comprehensive measurement of LV dysfunction than LVEF in EA, which could potentially be included as a supplementary diagnostic procedure in the evaluation of EA. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to assess the correlations of functional and dimensional parameters with the severity of tricuspid regurgitation in patients with Ebstein's anomaly (EA) by using cardiac magnetic resonance (CMR) imaging. Materials and Methods: Thirty-three patients with EA without previous cardiac surgery and 25 normal individuals were recruited and underwent both cardiac MR imaging and preoperative transthoracic echocardiography. The left ventricular (LV) functional parameters and dimensions of the right ventricle (RV) and LV were measured using 3.0-T cardiac MR imaging. Tricuspid regurgitation severity grading was estimated by echocardiography. The functional and dimensional parameters were compared between EA patients and controls using independent sample t-tests. Spearman's rank correlation was used to determine the correlations between the functional and dimensional parameters and tricuspid regurgitation. Receiver operating characteristic (ROC) analysis was used to predict tricuspid regurgitation severity using individual functional and dimensional parameters. Results: Statistical analysis revealed significant differences in the functional and dimensional parameters between EA patients and controls. Within the EA group, tricuspid valve regurgitation negatively correlated well with the left ventricular ejection fraction (LVEF) (r=-0.558, p=0.001). The ratio of the right ventricular (functional right ventricle) end-diastolic dimension to the left ventricle end-diastolic dimension (RVEDD/LVEDD) in EA patients also correlated well with the severity of tricuspid valve regurgitation (r=0.492, p=0.004). Moreover, ROC analysis revealed that high sensitivity and specificity were obtained for predicting the severity of tricuspid valve regurgitation with LVEF (78.3%, 90.0%) and RVEDD/LVEDD (78.3%, 94.3%). Conclusion: In EA patients, the left and right ventricular functional and dimensional parameters from MRI correlated well with tricuspid regurgitation, which helped predict the severity of EA. [ABSTRACT FROM AUTHOR]

This study aimed to explore the feasibility and accuracy of single-shot compressed-sensing (CS) cardiac magnetic resonance cine technology for the assessment of biventricular function and morphology in free-breathing (FB) pediatrics, especially those with arrhythmia. Seventy consecutive pediatric participants (6.27 ± 3.8 years, range:0.5–14 years) were enrolled between August 2019 and July 2020. Single-shot CS and conventional balanced steady-state free-precession (bSSFP) cine were obtained. The total scanning time, image quality and biventricular function parameters were compared for both sequences. Single-shot CS cine had shorter acquisition time compared with the conventional bSSFP cine (all P < 0.001). The single-shot CS cine also had fewer artifacts than conventional bSSFP cine (breath-hold (BH): 4.6 ± 0.6 vs. 4.3 ± 0.6; FB without ongoing arrhythmia: 4.5 ± 0.6 vs. 3.6 ± 0.9; FB with ongoing arrhythmia: 4.7 ± 0.5 vs. 2.6 ± 1.1; all P < 0.05). No statistical difference of left ventricular parameters and right ventricular end-systolic volume/ejection fraction were found between the single-shot CS and conventional bSSFP cine in both BH and FB without ongoing arrhythmia group. There was an excellent correlation (R 2 = 0.60–0.98, all P < 0.001) and good intra-(range: R 2 = 0.57–0.99, P < 0.001)/inter-observer agreements (range: R 2 = 0.76–1, P < 0.001) for single-shot CS cine images in terms of biventricular function parameters. The single-shot CS cine can significantly reduce the image acquisition time, offering reliable quantification of biventricular function in free breathing condition for arrhythmic patients. • Single-shot CS cine accelerated the CMR imaging in pediatric patients. • Single-shot CS cine offered accurate quantification of biventricular function with acceptable image quality. • Single-shot CS CMR cine provided an alternative option for free-breathing and arrhythmia children. [ABSTRACT FROM AUTHOR]