Dong Zhixiang, Tang Yun, Sun Peng, Yin Gang, Zhao Kankan, Ma Xuan, Yang Shujuan, Wang Jiaxin, Xiang Xiaorui, Yang Kai, Lu Minjie, Chen Xiuyu, Zhu Yanjie, Zhao Shihua
From the Department of Magnetic Resonance Imaging, Radiology Imaging Center, Fuwai Hospital, National Center for Cardiovascular Diseases, State Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beilishi Road No. 167, Xicheng District, Beijing 100037, China (Z.D., Y.T., G.Y., X.M., S.Y., J.W., X.X., K.Y., M.L., X.C., S.Z.); Clinical and Technical Support, Philips Healthcare, Beijing, China (P.S.); and Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, SZ University Town, Shenzhen, China (K.Z., Y.Z.).
Radiol Cardiothorac Imaging. 2025 Feb;7(1):e240009. doi: 10.1148/ryct.240009.
Purpose To explore the diffusion characteristics of hypertrophic cardiomyopathy (HCM) using in vivo cardiac diffusion-tensor imaging (cDTI) and to determine whether cDTI could help identify abnormal myocardium beyond cardiac MRI findings of fibrosis and hypertrophy. Materials and Methods In this prospective study conducted from April to August 2023, participants with HCM and healthy volunteers were enrolled for cardiac MRI evaluation, including cine, late gadolinium enhancement (LGE), T1 mapping, and cDT imaging, using a 3.0-T scanner. LGE was performed only in participants with HCM. All cardiac MR images of the midventricular section were divided into six American Heart Association segments for segmental analysis. Repeated measure analysis of variance and Friedman test were used to compare cDTI parameters among different segments, and a linear mixed-effects model was fitted to account for within-participant clustering. Diagnostic performance of cDTI parameters in discriminating HCM segments from normal segments was assessed using receiver operating characteristic (ROC) analysis. Results Thirty-five participants with HCM (mean age, 46 years ± 13 [SD]; 19 [54%] male) and 15 healthy volunteers (mean age, 43 years ± 17; nine [60%] male) were included. Compared with controls, the HCM group showed significantly reduced fractional anisotropy (FA) (mean, 0.33 ± 0.05 vs 0.46 ± 0.04; < .001) and increased diastolic second eigenvector angle (E2A) (mean, 48.85° ± 7.13 vs 35.05° ± 5.06; < .001). In segmental analysis, FA and diastolic E2A of HCM segments with no hypertrophy or LGE also significantly differed from controls (estimated marginal mean, FA: 0.39 [95% CI: 0.38, 0.41] vs 0.45 [95% CI: 0.43, 0.47]; E2A: 46.03° [95% CI: 43.45, 48.62] vs 35.69° [95% CI: 31.69, 39.69]; both < .001), with no evidence of a difference in native T1 values (estimated marginal mean, 1282.43 msec [95% CI: 1267.55, 1297.30] vs 1265.57 msec [95% CI: 1242.86, 1288.28]; = .47). FA (area under the ROC curve [AUC], 0.81 [95% CI: 0.76, 0.86]) and diastolic E2A (AUC, 0.79 [95% CI: 0.74, 0.84]) showed higher performance than native T1 (AUC, 0.67 [95% CI: 0.61, 0.72]) in identifying HCM segments from normal segments ( < .001 and = .007, respectively). Conclusion Myocardial disarray and abnormal microstructural dynamics of HCM can be identified by using in vivo cDTI even in the absence of hypertrophy or fibrosis, suggesting the potential value of cDTI in tissue characterization of HCM. Cardiovascular MR Imaging, Hypertrophic Cardiomyopathy, Diffusion-Tensor Imaging, Myocardial Microstructure Published under a CC BY 4.0 license.
目的 利用活体心脏扩散张量成像（cDTI）探索肥厚型心肌病（HCM）的扩散特征，并确定cDTI是否有助于识别超出心脏MRI纤维化和肥厚表现的异常心肌。材料与方法 在这项于2023年4月至8月进行的前瞻性研究中，招募了HCM患者和健康志愿者进行心脏MRI评估，包括电影成像、延迟钆增强（LGE）、T1 mapping和cDT成像，使用3.0-T扫描仪。仅对HCM患者进行LGE检查。将心室中段的所有心脏MR图像分为六个美国心脏协会节段进行节段分析。采用重复测量方差分析和Friedman检验比较不同节段的cDTI参数，并拟合线性混合效应模型以考虑受试者内部聚类。使用受试者操作特征（ROC）分析评估cDTI参数在区分HCM节段和正常节段中的诊断性能。结果 纳入了35例HCM患者（平均年龄46岁±13[标准差]；19例[54%]男性）和15名健康志愿者（平均年龄43岁±17；9例[60%]男性）。与对照组相比，HCM组的分数各向异性（FA）显著降低（平均值，0.33±0.05对0.46±0.04；P<0.001），舒张期第二特征向量角（E2A）增加（平均值，48.85°±7.13对35.05°±5.06；P<0.001）。在节段分析中，无肥厚或LGE表现的HCM节段的FA和舒张期E2A也与对照组有显著差异（估计边际均值FA：0.39[95%可信区间：0.38，0.41]对0.45[95%可信区间：0.43，0.47]；E2A：46.03°[95%可信区间：43.45，48.62]对35.69°[95%可信区间：31.69，39.69]；均P<0.001），而固有T1值无差异证据（估计边际均值，1282.43毫秒[95%可信区间：1267.55，1297.30]对1265.57毫秒[95%可信区间：1242.86，1288.28]；P=0.47）。在从正常节段识别HCM节段方面，FA（ROC曲线下面积[AUC]，0.81[95%可信区间：0.76，0.86]）和舒张期E2A（AUC，0.79[95%可信区间：0.74，0.84]）的表现优于固有T1（AUC，0.67[95%可信区间：0.61，0.72]）（分别为P<0.001和P=0.007）。结论 即使在无肥厚或纤维化的情况下，使用活体cDTI也可识别HCM的心肌排列紊乱和异常微观结构动力学，提示cDTI在HCM组织特征化方面的潜在价值。心血管磁共振成像、肥厚型心肌病、扩散张量成像、心肌微观结构 本文在知识共享署名4.0许可下发表。
