Cardiovascular Research and Development Center, Faculty of Medicine of the University of Porto, Porto, Portugal
Cardiology Department, Gaia Hospital Centre, Vila Nova de Gaia, Portugal.
Diabetes. 2018 May;67(5):1007-1012. doi: 10.2337/db17-1496. Epub 2018 Feb 14.
The relationship of metabolic syndrome (MetS) and insulin resistance (one of its key pathophysiological mediators) with diastolic dysfunction and myocardial fibrosis is not well understood. This study aimed to evaluate the association of MetS with diastolic function and myocardial extracellular matrix (ECM) using cardiac MRI (CMRI) in a large community-based population. This cross-sectional analysis included 1,582 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) with left ventricular ejection fraction ≥50% and no history of cardiac events. Diastolic function was assessed using tagged CMRI parameters including end-diastolic strain rate (EDSR) and strain relaxation index (SRI). ECM was evaluated using extracellular volume (ECV) quantification. Participants' mean age was 67.4 ± 8.6 years, and 48.1% were males. MetS was present in 533 individuals (33.7%), and type 2 diabetes in 250 (15.8%). In the multivariable analyses, MetS (irrespective of the presence of type 2 diabetes) and higher insulin resistance were associated with impaired diastolic function (higher SRI and lower EDSR), independent of ECV. In conclusion, MetS, irrespective of the presence of type 2 diabetes, was independently associated with impaired diastole. These functional myocardial changes seem to result from intrinsic cardiomyocyte alterations, irrespective of the myocardial interstitium (including fibrosis).
代谢综合征（MetS）及其关键病理生理介质之一胰岛素抵抗与舒张功能障碍和心肌纤维化之间的关系尚未得到充分理解。本研究旨在使用心脏磁共振成像（CMRI）评估代谢综合征与舒张功能和心肌细胞外基质（ECM）之间的关联，研究对象为多民族动脉粥样硬化研究（MESA）中的 1582 名左心室射血分数≥50%且无心脏事件史的参与者。舒张功能使用包括舒张末期应变率（EDSR）和应变松弛指数（SRI）在内的标记 CMRI 参数进行评估。使用细胞外容积（ECV）定量评估 ECM。参与者的平均年龄为 67.4±8.6 岁，48.1%为男性。533 名参与者（33.7%）患有代谢综合征，250 名参与者（15.8%）患有 2 型糖尿病。多变量分析显示，无论是否存在 2 型糖尿病，代谢综合征（MetS）和更高的胰岛素抵抗与舒张功能障碍（更高的 SRI 和更低的 EDSR）相关，独立于 ECV。总之，无论是否存在 2 型糖尿病，代谢综合征都与舒张功能障碍独立相关。这些功能性心肌变化似乎是由于心肌细胞本身的改变引起的，与心肌间质（包括纤维化）无关。
