The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Mallinckrodt Institute of Radiology, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
Magn Reson Imaging. 2022 Sep;91:1-8. doi: 10.1016/j.mri.2022.05.001. Epub 2022 May 4.
To determine the sensitivity of a noncontrast T1 dispersion cardiovascular magnetic resonance technique for detecting diffuse fibrosis in hypertrophic cardiomyopathy (HCM).
Thirty-two adult HCM patients and ten age- and gender-matched healthy volunteers were prospectively included in this study. Patients and controls underwent cine, T1ρ-mapping, and pre- and post-contrast T1-mapping imaging using a 3-T magnetic resonance system. Myocardial extracellular volume fraction (ECV) maps were obtained using pre- and post-contrast T1 maps to determine reference values for diffuse fibrosis. Myocardial T1ρ and T1ρ dispersion maps called myocardial fibrosis index (mFI) maps provided 570 myocardial segments for Pearson or Spearman correlation analysis. The left ventricle myocardia of the HCM patients were divided into 16 segments that were further classified as either normal-thickness myocardium (<15 mm) (HCM-N) or hypertrophic myocardium (≥15 mm) (HCM-H).
ECV and mFI values increased progressively on a per-segment basis from healthy controls to the HCM-N group and then to the HCM-H group (ECV: 27.4 ± 2.8% vs. 31.1 ± 4.2% vs. 37.6 ± 6.9%, respectively [P < 0.0001]; mFI: 6.1 ± 0.9 ms vs. 8 ± 1.9 ms vs. 11 ± 3.3 ms, respectively [P < 0.0001]). There was a strong positive correlation between the segmented ECV and the mFI (r = 0.878). The mFI was equally or significantly better than the ECV for differentiating fibrosis content in HCM-N and HCM-H according to their receiver operating characteristic curves.
A T1ρ dispersion imaging mFI can sensitively detect diffuse myocardial fibrosis in HCM, even in HCM-N.
确定非对比 T1 弥散心血管磁共振技术检测肥厚型心肌病（HCM）弥漫性纤维化的敏感性。
本研究前瞻性纳入 32 例成年 HCM 患者和 10 名年龄和性别匹配的健康志愿者。患者和对照组接受电影、T1ρ 映射和预对比及对比后 T1 映射成像，使用 3-T 磁共振系统。通过预对比和对比 T1 图获得心肌细胞外容积分数（ECV）图，以确定弥漫性纤维化的参考值。心肌 T1ρ 和 T1ρ 弥散图（称为心肌纤维化指数（mFI）图）为 570 个心肌节段提供 Pearson 或 Spearman 相关分析。HCM 患者的左心室心肌分为 16 个节段，进一步分为正常厚度心肌（<15mm）（HCM-N）或肥厚心肌（≥15mm）（HCM-H）。
ECV 和 mFI 值逐节从健康对照组到 HCM-N 组再到 HCM-H 组逐渐增加（ECV：27.4±2.8%比 31.1±4.2%比 37.6±6.9%，P<0.0001；mFI：6.1±0.9ms 比 8±1.9ms 比 11±3.3ms，P<0.0001）。分段 ECV 与 mFI 之间存在很强的正相关（r=0.878）。根据受试者工作特征曲线，mFI 对区分 HCM-N 和 HCM-H 中的纤维化含量与 ECV 同样或更有优势。
T1ρ 弥散成像 mFI 可以敏感地检测 HCM 中的弥漫性心肌纤维化，即使在 HCM-N 中也是如此。
