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An abstract of the paper "CMR Real-Time, Free-Breathing, Phase Contrast Flow Quantification: A Novel Approach to Assess Ventricular Coupling in Constrictive Pericarditis," by David Verhaert and colleagues is presented.

Background: Myocardial edema in acute myocardial infarction (AMI) is commonly imaged using dark-blood short tau inversion recovery turbo spin echo (STIR-TSE) cardiovascular magnetic resonance (CMR). The technique is sensitive to cardiac motion and coil sensitivity variation, leading to myocardial signal nonuniformity and impeding reliable depiction of edematous tissues. T2-prepared balanced steady state free precession (T2p-bSSFP) imaging has been proposed, but its contrast is low, and averaging is commonly needed. T2 mapping is useful but requires a long scan time and breathholding. We propose here a single-shot magnetization prepared sequence that increases the contrast between edema and normal myocardium and apply it to myocardial edema imaging. Methods: A magnetization preparation module (T2STIR) is designed to exploit the simultaneous elevation of T1 and T2 in edema to improve the depiction of edematous myocardium. The module tips magnetization down to the –z axis after T2 preparation. Transverse magnetization is sampled at the fat null point using bSSFP readout and allows for single-shot myocardial edema imaging. The sequence (T2STIR-bSSFP) was studied for its contrast behavior using simulation and phantoms. It was then evaluated on 7 healthy subjects and 7 AMI patients by comparing it to T2p-bSSFP and T2 mapping using the contrast-to-noise ratio (CNR) and the contrast ratio as performance indices. Results: In simulation and phantom studies, T2STIR-bSSFP had improved contrast between edema and normal myocardium compared with the other two edema imaging techniques. In patients, the CNR of T2STIR-bSSFP was higher than T2p-bSSFP (5.9 ± 2.6 vs. 2.8 ± 2.0, P < 0.05) but had no significant difference compared with that of the T2 map (T2 map: 6.6 ± 3.3 vs. 5.9 ± 2.6, P = 0.62). The contrast ratio of T2STIR-bSSFP (2.4 ± 0.8) was higher than that of the T2 map (1.3 ± 0.1, P < 0.01) and T2p-bSSFP (1.4 ± 0.5, P < 0.05). Conclusion: T2STIR-bSSFP has improved contrast between edematous and normal myocardium compared with commonly used bSSFP-based edema imaging techniques. T2STIR-bSSFP also differentiates between fat that was robustly suppressed and fluids around the heart. The technique is useful for single-shot edema imaging in AMI patients. [ABSTRACT FROM AUTHOR]

Background: Myocardial fibrosis is a common pathophysiological process that is related to ventricular remodeling in congenital heart disease. However, the presence, characteristics, and clinical significance of myocardial fibrosis in Ebstein's anomaly have not been fully investigated. This study aimed to evaluate myocardial fibrosis using cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) and T1 mapping techniques, and to explore the significance of myocardial fibrosis in adolescent and adult patients with Ebstein's anomaly. Methods: Forty-four consecutive patients with unrepaired Ebstein's anomaly (34.0 ± 16.2 years; 18 males), and an equal number of age- and gender-matched controls, were included. A comprehensive CMR protocol consisted of cine, LGE, and T1 mapping by modified Look-Locker inversion recovery (MOLLI) sequences were performed. Ventricular functional parameters, native T1, extracellular volume (ECV), and LGE were analyzed. Associations between myocardial fibrosis and disease severity, ventricular function, and NYHA classification were analyzed. Results: LGE was found in 10 (22.7%) patients. Typical LGE in Ebstein's anomaly was located in the endocardium of the septum within the right ventricle (RV). The LV ECV of Ebstein's anomaly were significantly higher than those of the controls (30.0 ± 3.8% vs. 25.3 ± 2.3%, P < 0.001). An increased ECV was found to be independent of the existence of LGE. Positive LGE or higher ECV (≥30%) was associated with larger fRV volume, aRV volume, increased disease severity, and worse NYHA functional class. In addition, ECV was significantly correlated with the LV ejection fraction (P < 0.001). Conclusions: Both focal and diffuse myocardial fibrosis were observed in adolescent and adult patients with Ebstein's anomaly. Increased diffuse fibrosis is associated with worse LV function, increased Ebstein's severity, and worse clinical status. [ABSTRACT FROM AUTHOR]