Department of Cardiology, Princess Alexandra Hospital (A.C.T.N., L.G., S.Y.G., W.Y.S.W.).
Centre for Advanced Imaging (A.C.T.N., G.C., W.Y.S.W.).
Circ Cardiovasc Imaging. 2018 Aug;11(8):e007372. doi: 10.1161/CIRCIMAGING.117.007372.
Background Current understanding of metabolic heart disease consists of a myriad of different pathophysiological mechanisms. Epicardial adipose tissue (EAT) is increasingly recognized as metabolically active and associated with adverse cardiovascular outcomes. The present study aimed to investigate the effect of increased EAT volume index on left ventricular (LV) myocardial fat content and burden of interstitial myocardial fibrosis and their subsequent effects on LV myocardial contractile function. Methods and Results A total of 40 volunteers (mean age, 35±10 years; 26 males) of varying body mass index (25.0±4.1 kg/m; range, 19.3-36.3 kg/m) and without diabetes mellitus or hypertension were prospectively recruited. EAT volume index, LV myocardial fat content, and extracellular volume were quantified by magnetic resonance imaging. LV myocardial contractile function was quantified by speckle tracking echocardiography global longitudinal strain on the same day as magnetic resonance imaging examination. Mean total EAT volume index, LV myocardial fat content, and extracellular volume were 30.0±19.6 cm/m, 5.06%±1.18%, and 27.5%±0.5%, respectively. On multivariable analyses, increased EAT volume index and insulin resistance were independently associated with both increased LV myocardial fat content content and higher burden of interstitial myocardial fibrosis. Furthermore, increased EAT volume index was independently associated with LV global longitudinal strain. Conclusions Increased EAT volume index and insulin resistance were independently associated with increased myocardial fat accumulation and interstitial myocardial fibrosis. Increased EAT volume index was associated with detrimental effects on myocardial contractile function as evidenced by a reduction in LV global longitudinal strain.
背景 当前对于代谢性心脏病的理解包含了大量不同的病理生理学机制。心外膜脂肪组织（EAT）作为一种代谢活跃的组织，与不良心血管结局相关，其重要性日益得到重视。本研究旨在探讨 EAT 体积指数增加对左心室（LV）心肌脂肪含量和间质心肌纤维化负担的影响，及其对 LV 心肌收缩功能的后续影响。
方法和结果 本研究前瞻性纳入了 40 名志愿者（平均年龄 35±10 岁；26 名男性），其体质量指数（BMI）各不相同（25.0±4.1 kg/m；范围 19.3-36.3 kg/m），且无糖尿病或高血压。采用磁共振成像（MRI）定量评估 EAT 体积指数、LV 心肌脂肪含量和细胞外容积；同时在 MRI 检查同日采用斑点追踪超声心动图定量评估 LV 心肌收缩功能。平均总 EAT 体积指数、LV 心肌脂肪含量和细胞外容积分别为 30.0±19.6 cm/m、5.06%±1.18%和 27.5%±0.5%。多变量分析显示，EAT 体积指数增加和胰岛素抵抗与 LV 心肌脂肪含量增加和间质心肌纤维化负担加重独立相关。此外，EAT 体积指数增加与 LV 整体纵向应变独立相关。
结论 EAT 体积指数增加和胰岛素抵抗与心肌脂肪堆积和间质心肌纤维化增加独立相关。EAT 体积指数增加与 LV 整体纵向应变降低相关，表明其对心肌收缩功能有不利影响。
