From the Departments of Radiology (A.A., M.C.M., H.B., S.P.A., P.J.R., J.D.T., K.G., Y.S., A.M., K.K., R.L.E., P.A.A.), Quantitative Health Science (T.G.), and Cardiology (A.M.A.O.), Mayo Clinic, 200 First St SW, Rochester, MN 55905.
Radiol Cardiothorac Imaging. 2024 Jun;6(3):e230140. doi: 10.1148/ryct.230140.
Purpose To investigate the feasibility of using quantitative MR elastography (MRE) to characterize the influence of aging and sex on left ventricular (LV) shear stiffness. Materials and Methods In this prospective study, LV myocardial shear stiffness was measured in 109 healthy volunteers (age range: 18-84 years; mean age, 40 years ± 18 [SD]; 57 women, 52 men) enrolled between November 2018 and September 2019, using a 5-minute MRE acquisition added to a clinical MRI protocol. Linear regression models were used to estimate the association of cardiac MRI and MRE characteristics with age and sex; models were also fit to assess potential age-sex interaction. Results Myocardial shear stiffness significantly increased with age in female (age slope = 0.03 kPa/year ± 0.01, = .009) but not male (age slope = 0.008 kPa/year ± 0.009, = .38) volunteers. LV ejection fraction (LVEF) increased significantly with age in female volunteers (0.23% ± 0.08 per year, = .005). LV end-systolic volume (LVESV) decreased with age in female volunteers (-0.20 mL/m ± 0.07, = .003). MRI parameters, including T1, strain, and LV mass, did not demonstrate this interaction ( > .05). Myocardial shear stiffness was not significantly correlated with LVEF, LV stroke volume, body mass index, or any MRI strain metrics ( > .05) but showed significant correlations with LV end-diastolic volume/body surface area (BSA) (slope = -3 kPa/mL/m ± 1, = .004, = 0.08) and LVESV/BSA (-1.6 kPa/mL/m ± 0.5, = .003, = 0.08). Conclusion This study demonstrates that female, but not male, individuals experience disproportionate LV stiffening with natural aging, and these changes can be noninvasively measured with MRE. Cardiac, Elastography, Biological Effects, Experimental Investigations, Sexual Dimorphisms, MR Elastography, Myocardial Shear Stiffness, Quantitative Stiffness Imaging, Aging Heart, Myocardial Biomechanics, Cardiac MRE . Published under a CC BY 4.0 license.
目的 探讨使用定量磁共振弹性成像（MRE）来描述年龄和性别对左心室（LV）剪切刚度的影响的可行性。
材料与方法 本前瞻性研究纳入了 2018 年 11 月至 2019 年 9 月期间的 109 名健康志愿者（年龄范围：18-84 岁；平均年龄 40 岁±18[标准差]；57 名女性，52 名男性），使用 5 分钟的 MRE 采集来增加临床 MRI 方案，以测量 LV 心肌剪切刚度。线性回归模型用于估计心脏 MRI 和 MRE 特征与年龄和性别的相关性；模型还拟合以评估潜在的年龄性别交互作用。
结果 女性志愿者的心肌剪切刚度随年龄显著增加（年龄斜率=0.03 kPa/年±0.01，=.009），而男性志愿者则无此变化（年龄斜率=0.008 kPa/年±0.009，=.38）。女性志愿者的 LV 射血分数（LVEF）随年龄显著增加（每年增加 0.23%±0.08，=.005）。女性志愿者的 LV 收缩末期容积（LVESV）随年龄减少（每年减少 0.20 毫升/米±0.07，=.003）。MRI 参数，包括 T1、应变和 LV 质量，没有显示出这种相互作用（>.05）。心肌剪切刚度与 LVEF、LV 每搏量、体重指数或任何 MRI 应变指标均无显著相关性（>.05），但与 LV 舒张末期容积/体表面积（BSA）（斜率=-3 kPa/mL/m±1，=.004，= 0.08）和 LVESV/BSA（斜率=-1.6 kPa/mL/m±0.5，=.003，= 0.08）有显著相关性。
结论 本研究表明，女性而非男性个体在自然衰老过程中会出现不成比例的 LV 僵硬度增加，并且这些变化可以使用 MRE 进行无创测量。
心脏；弹性成像，生物学效应；实验研究；性别差异；磁共振弹性成像；心肌剪切刚度；定量硬度成像；衰老心脏；心肌生物力学；心脏 MRE。
