Vasanji Zainisha, Sigal Ronald J, Eves Neil D, Isaac Debra L, Friedrich Matthias G, Chow Kelvin, Thompson Richard B
Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.
Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
J Appl Physiol (1985). 2017 Aug 1;123(2):394-401. doi: 10.1152/japplphysiol.00012.2017. Epub 2017 May 18.
Individuals with type 1 diabetes (T1D) characteristically have high glycemic levels that over time can result in reactive fibrosis and abnormalities in myocardial function. T mapping with magnetic resonance imaging (MRI) can estimate the extent of reactive fibrosis by measurement of the extracellular volume fraction (ECV). The extent of alterations in the ECV and associated changes in left ventricular (LV) function and morphology in individuals with T1D is unknown. Fourteen individuals with long-term T1D and 14 sex-, age-, and body mass index-matched controls without diabetes underwent MRI measurement of myocardial T and ECV values as well as LV function and morphology. Ventricular mass, volumes, and global function (LVEF and circumferential/longitudinal/radial strain) were similar in those with T1D and controls. However, those with T1D had larger myocardial ECV (22.1 ± 1.8 vs. 20.1 ± 2.1, = 0.008) and increased native (noncontrast) myocardial T values (1,211 ± 44 vs. 1,172 ± 43 ms, < 0.001) as compared with controls. Both the ECV and native T values significantly correlated with several components of torsion and circumferential-longitudinal shear strain (, the shear strain component associated with twist). Individuals with T1D had increased systolic torsion ( = 0.035), systolic torsion rate ( = 0.032), peak ( = 0.001), and rates of change of systolic ( = 0.007) and diastolic ( = 0.007) Individuals with T1D, with normal structure, LVEF, and strain, have increased extracellular volume and increased native T values with associated augmented torsion and These measures may be useful in detecting the early stages of diabetic cardiomyopathy and warrant larger prospective studies. Individuals with type 1 diabetes, with normal left ventricular structure and function (ejection fraction and strain), have signs of interstitial fibrosis, measured with MRI as increased extracellular volume fraction and increased native myocardial T, which significantly correlated with a number of measures of augmented left ventricular twist function. These measures may be useful in detecting the early stages of diabetic cardiomyopathy.
1型糖尿病（T1D）患者的血糖水平通常较高，随着时间的推移，可能会导致反应性纤维化和心肌功能异常。通过磁共振成像（MRI）进行T值映射可以通过测量细胞外容积分数（ECV）来估计反应性纤维化的程度。T1D患者的ECV改变程度以及左心室（LV）功能和形态的相关变化尚不清楚。14名患有长期T1D的患者和14名年龄、性别、体重指数匹配的非糖尿病对照者接受了MRI检查，测量心肌T值和ECV值以及LV功能和形态。T1D患者和对照者的心室质量、容积和整体功能（左心室射血分数和圆周/纵向/径向应变）相似。然而，与对照者相比，T1D患者的心肌ECV更大（22.1±1.8 vs. 20.1±2.1，P = 0.008），并且天然（非对比）心肌T值增加（1211±44 vs. 1172±43 ms，P < 0.001）。ECV和天然T值均与扭转和圆周-纵向剪切应变的几个分量显著相关（γ，与扭转相关的剪切应变分量）。T1D患者的收缩期扭转增加（P = 0.035）、收缩期扭转率增加（P = 0.032）、峰值γ增加（P =
