Liu Jing, Li Jing, Pu Huaxia, He Wenzhang, Zhou Xiaoyue, Tong Nanwei, Peng Liqing
Department of Radiology, West China Hospital, Sichuan University, Chengdu, China.
Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, China.
Quant Imaging Med Surg. 2022 Mar;12(3):2035-2050. doi: 10.21037/qims-21-724.
Obesity often exists alongside comorbidities and increases the risk of heart failure and cardiovascular mortality. However, the specific effects of obesity on cardiac structure and function have not been clarified. This study set out to evaluate left ventricular (LV) geometric and functional changes using cardiovascular magnetic resonance imaging (CMR) in adults with uncomplicated obesity.
Forty-eight patients with uncomplicated obesity [body mass index (BMI) mean ± SD: 29.8±2.1 kg/m] and 25 healthy controls were included in this study. CMR was used to assess LV geometry, global systolic function, and strains, and to quantify epicardial adipose tissue (EAT). Body composition was measured by dual X-ray absorptiometry.
Compared with healthy controls, patients with obesity had increased LV size, mass, and myocardial thickness, and impaired myocardial contractility, with lower global radial, circumferential, and longitudinal peak strains (PS), and circumferential and longitudinal peak diastolic strain rates (PDSR; all P<0.05). Multivariable linear regression showed that BMI was independently associated with LV maximum myocardial thickness (LVMMT) (β=0.197, P=0.016). Visceral adipose tissue (VAT) was independently associated with LV global longitudinal PS (β=-2.684, P=0.001), and both longitudinal (β=-0.192, P=0.002) and circumferential (β=-0.165, P=0.014) PDSR. Homeostasis model assessment of insulin resistance (HOMA-IR) was mildly correlated with BMI (r=0.327) and body fat percentage (BF%) (r=0.295) in patients with obesity (all P<0.05). HOMA-IR was independently associated with LV global circumferential PS (β=-0.276, P=0.04) and PDSR (β=-0.036, P=0.026).
Extensive LV geometric remodeling and marked changes in cardiac strains were observed in adults with obesity. Tissue tracking with CMR can reveal subclinical impaired ventricular function with preserved LV ejection fraction in such patients. BMI was independently related to LV remodeling in obesity. HOMA-IR and VAT are potentially superior to BMI as predictors of subclinical dysfunction, assessed by strain, in obesity.
This study has been registered with the Chinese Clinical Trial Registry (ID: ChiCTR1900026476; Effect of lifestyle intervention on metabolism of obese patients based on smart phone software).
肥胖常与合并症并存，并增加心力衰竭和心血管疾病死亡率的风险。然而，肥胖对心脏结构和功能的具体影响尚未阐明。本研究旨在使用心血管磁共振成像（CMR）评估单纯性肥胖成年人的左心室（LV）几何形态和功能变化。
本研究纳入了48例单纯性肥胖患者[体重指数（BMI）均值±标准差：29.8±2.1kg/m²]和25名健康对照者。采用CMR评估左心室几何形态、整体收缩功能和应变，并量化心外膜脂肪组织（EAT）。通过双能X线吸收法测量身体成分。
与健康对照者相比，肥胖患者的左心室大小、质量和心肌厚度增加，心肌收缩力受损，整体径向、圆周和纵向峰值应变（PS）较低，圆周和纵向舒张期峰值应变率（PDSR；均P<0.05）。多变量线性回归显示，BMI与左心室最大心肌厚度（LVMMT）独立相关（β=0.197，P=0.016）。内脏脂肪组织（VAT）与左心室整体纵向PS独立相关（β=-2.684，P=0.001），以及纵向（β=-0.192，P=0.002）和圆周（β=-0.165，P=0.014）PDSR。肥胖患者中，胰岛素抵抗的稳态模型评估（HOMA-IR）与BMI（r=0.327）和体脂百分比（BF%）（r=0.295）轻度相关（均P<0.05）。HOMA-IR与左心室整体圆周PS独立相关（β=-0.276，P=0.04）和PDSR（β=-0.036，P=0.026）。
在肥胖成年人中观察到广泛的左心室几何形态重塑和心脏应变的显著变化。CMR组织追踪可揭示此类患者左心室射血分数保留的亚临床心室功能受损。BMI与肥胖患者的左心室重塑独立相关。HOMA-IR和VAT作为肥胖患者亚临床功能障碍的预测指标，通过应变评估可能优于BMI。
本研究已在中国临床试验注册中心注册（注册号：ChiCTR1900026476；基于智能手机软件的生活方式干预对肥胖患者代谢的影响）。
