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Objective:To investigate the clinical and cardiac magnetic resonance (CMR) characteristics of heart involvement in patients with Fabry disease (AFD).Methods:From January 2018 to March 2021, eight AFD patients [3 males and 5 females, mean age (50±11) years old, range 26-60 years old] confirmed by genetic testing or pathology in Fuwai Hospital were retrospectively included in this study. At the same time, sixteen patients with hypertrophic cardiomyopathy (HCM) [6 males and 10 females, mean age (46±15) years old] and 16 healthy individuals [6 males and 10 females, mean age (51±11) years old] were included as controls. The clinical baseline data and CMR data of the patients were collected and analyzed. The CMR data were analyzed using the software CVI42, with the corresponding parameters automatically generated. One-way ANOVA or Kruskal-Wallis test was used to compare the differences in the parameters among the three groups. Independent-samples t test, Fisher precise test or Mann-Whitney U test were used for the comparison between each two groups. Results:Statistically significant difference was found in renal insufficiency between the HCM group and the AFD group; No other significant difference was found in other clinical factors and ECG results (all P>0.05). CMR results showed that in the AFD group, there were 5 cases with symmetric or roughly symmetric hypertrophy, and 3 with asymmetric hypertrophy. The late gadolinium enhancement (LGE) showed myocardial enhancement in 5 patients, mainly presenting as multiple intermural enhancement, and partially as local subendocardial enhancement. In the HCM group, fourteen cases suffered mainly asymmetric ventricular septal thickening, with or without thickening of other parts of left ventricular wall; and 2 cases had thickening of middle and distal part of the left ventricle. The LGE showed myocardial enhancement in 14 patients, which manifested as focal or patchy enhancement in hypertrophic myocardium, including focal enhancement in the right ventricular insertion of ventricular septum (more common) and subendocardial enhancement in the middle and far segments of left ventricle. Statistically significant difference was found in the differences between the left atrial anterior posterior diameter, the maximum wall thickness of left ventricular, the left ventricular myocardial mass index (LVMI) and the native T 1 value among the three groups (all P<0.001). However, there was no statistically significant difference in the left atrial anterior posterior diameter and the maximum wall thickness of left ventricular between AFD group and HCM group ( P>0.05). The LVMI in AFD group was higher than that in healthy group and HCM group (all P<0.05). Significant difference was found in the native T 1 value among the three groups, with the native T 1 value of the AFD group [(1 177.4±46.0) ms] was significantly lower than that of the healthy group [(1 244.5±34.3) ms] and the HCM group [(1 278.8±41.6) ms], with ( F=13.10, P<0.001). Conclusions:The clinical characteristics of AFD and HCM are quite similar. When AFD is suspected, CMR imaging should be the first choice for imaging examination. Especially, T 1 mapping imaging can provide important information for the diagnosis of AFD.
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Objective:To explore the clinical value of T 1 mapping/indexed extracellular volume fraction (iECV) quantified with cardiac MR (CMR) parameters, and its correlation with traditional indicators of myocardial dysfunction in aortic insufficiency (AI) patients. Methods:A total of 36 patients clinically and radiologically diagnosed with chronic AI in our hospital between May 2012 and February 2016 were retrospectively selected. All AI patients underwent conventional CMR protocol, native and post T 1 mapping. CMR parameters, such as aortic regurgitant fraction (RF), late gadolinium enhancement (LGE) mass fraction, myocardial extracellular volume fraction (ECV) and iECV. Based on the values of aortic RF, AI patients were divided into mild AI group (9 cases), moderate AI group (14 cases) and severe AI group (13 cases). The clinical characteristics were teased from the patients′ electronic medical records. Univariate analysis of variance was used to compare the measurement data of native T 1 mapping, post-contrast T 1 mapping, ECV, and iECV. LSD test was used for pair wise comparison between the mild AI, moderate AI and severe AI groups. Data about cardiovascular history, New York Heart Association (NYHA) heart function classification, and LGE were compared by chi-square test or Fisher exact test. The correlation between left ventricle ejection fraction (LVEF) and iECV was evaluated by Spearman correlation analysis. Results:There was no difference in age, sex, cardiovascular history among the three groups. Comparison of patients with different severity of AI in the three groups: (1) There was statistically significant difference in the LGE positive rate among the three groups ( P=0.023), while the myocardial replacement of fibrosis increased with the grade of aortic regurgitation. (2) There was no statistically significant difference in the measurement data of native T 1 mapping, post-contrast T 1 mapping, ECV among the three groups ( H=1.815, 0.929, 2.496, all P values>0.05), while the diffuse myocardial fibrosis tended to increase with the degree of aortic regurgitation. There was statistically significant difference in iECV among the three groups ( H=16.725, P<0.001). The measurement data of iECV in the severe AI group was significantly higher than those in the other two groups ( P<0.05). LVEF value was inversely correlated with iECV ( r=-0.649, P<0.001). Conclusions:Quantitative T 1 mapping/iECV can serve as a parameter to noninvasively identify diffuse myocardial fibrosis in AI patients of different severities. It changes with LVEF and can manifest the reversible stage of left ventricular decompensation.
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Valvular heart disease (VHD) is one kind of the main causes of cardiovascular events in the elderly patients. Cardiac imaging evaluation plays a critical role in the diagnosis and selection of treatment options for VHD. New cardiovascular MR (CMR) techniques have been increasingly used for VHD patients, of which 4D Flow MRI-derived hemodynamic parameters can be used to estimate transvalvular blood flow velocities, pressure gradients, wall shear stress and flow patterns, T1 mapping and extracellular volume fraction enable quantification of changes of early ventricular remodeling secondary to VHD, strain analysis can be used to assess early myocardial dysfunction. The application progresses of new CMR techniques on VHD were reviewed in this article.
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Objective@#To investigate the cardiovascular magnetic resonance (CMR) imaging characteristics and influence factors of aortic insufficiency (AI) patients with myocardial fibrosis.@*Method@#This retrospective study included 59 AI patients who received CMR and transthoracic echocardiography (TTE) examinations from June 2011 to February 2015. AI patients were divided into 2 groups: bicuspid aortic valve (BAV) group (n=30) and non-BAV group (n=29). Patients were also divided into late gadolinium enhancement (LGE) group (n=27) and non-LGE group (n=32). The baseline clinical characteristics were collected through electronic medical records. Hemodynamic parameters such as grade of AI, cardiac functional parameters and LGE mass fraction (LGE%) were measured by CMR post-processing analysis. Kappa test was used to assess the consistency of AI severity between CMR and TTE, and the multivariate logistic regression analysis was performed to evaluate influence factors of myocardial fibrosis in AI patients.@*Results@#(1) 56 (94.9%) patients were male, and the mean age was (44.2±11.0) years old. There was no significant difference in age and gender, hypertension, hyperlipidemia, alcoholic consumption between BAV and non-BAV group (all P>0.05). There were a higher proportion of smoking history (P=0.008), a lower body mass index (BMI) (P=0.020) in the LGE group than in the non-LGE group. (2) The accuracy of CMR in diagnosis of BAV was 96.7% (29/30) compared to the gold standard. In the BAV group, 20 patients (66.7%) were with fusion of left and right cusp (L-R), 5 patients (16.7%) were with fusion of right and noncoronary cusp (R-N), 5 patients (16.7%) were with fusion of left and noncoronary cusp (L-N); patients with BAV had larger left ventricular end diastolic volume index (LVEDVi), left ventricular end systolic volume index (LVESVi), higher proportion of LGE and lower left ventricular ejection fraction (LVEF) than those in non-BAV group (all P<0.05). There were 19 patients with BAV in the LGE group, the cases of L-R, R-N, L-N were 10 (52.6%), 5 (26.3%), and 4 (21.1%), respectively. In the non-LGE group, patients with BAV of L-R, R-N, L-N were 10 (90.9%), 0, and 1 (9.1%), respectively. Patients with LGE had lower body surface area (BSA), LVEF and larger LVEDVi, LVESVi, left ventricular mass index (LVMi) and higher proportion of BAV compared patients without LGE. In addition, the proportion of moderate and severe AI patients was significantly higher in BAV group than in non-BAV group (P=0.009). (3) The consistency of CMR and TTE in evaluating the severity of AI patients: the agreement between TTE and CMR regarding AI severity was satisfactory (kappa value was 0.624, 95%CI 0.402-0.831, P<0.001). (4) The linear regression analysis demonstrated a negative correlation between LVEF and LGE% in BAV and non-BAV group (P<0.001). The multivariate logistic regression analysis showed that the presence of BAV was an independent risk factor of left ventricucar fibrosis (OR=5.050, 95%CI 1.220-20.908, P=0.025) after adjustment for LVEF, hypertension, LVEDVi and LVMi.@*Conclusion@#Multi-parametric CMR provides a satisfactory noninvasive tool for estimation of myocardial fibrosis and ventricular remodeling in patients with AI, and BAV is an independent risk factor for myocardial fibrosis in patients with AI.