Liu Juan, Wang Yixuan, Zhang Jun, Li Xin, Tan Lin, Huang Haiyun, Dai Yang, Shang Yongning, Shen Ying
Department of Ultrasound, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
Department of Cardiovascular Medicine, Rui Jin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Front Cardiovasc Med. 2023 Feb 23;10:1109946. doi: 10.3389/fcvm.2023.1109946. eCollection 2023.
This experimental study aimed to determine the dynamic changes in myocardial strain and microvascular perfusion in diabetic rats by comprehensive echocardiography while evaluating the effect of dapagliflozin (DAPA).
Male Sprague-Dawley rats ( = 128) were randomly divided into four groups based on the presence or absence of a high-fat diet and streptozotocin-induced diabetes with or without DAPA treatment ( = 32/group). Serial conventional ultrasound, two-dimensional speckle tracking echocardiography (2D-STE) and myocardial contrast echocardiography (MCE) were performed at 2, 4, 6, and 8 weeks, and left ventricular global longitudinal strain (GLS), myocardial blood flow velocity (MBFV), myocardial blood flow (MBF), and myocardial blood volume (MBV) were determined. All animals were sacrificed immediately after the last echo measurement for histopathological assessment.
Despite similar conventional Doppler-echo indexes among the groups at 2, 4, 6, and 8 weeks ( > 0.05), left ventricular GLS, MBFV, MBF, and MBV were decreased at 8 weeks in diabetic rats ( < 0.05) as detected by both 2D-STE and MCE. These indexes were significantly improved at 6 and 8 weeks after treatment with DAPA for diabetic rats ( < 0.05), reaching similar values observed in non-diabetic controls. DAPA treatment was associated with increased myocardial vacuolization and microvessel density and reduced interstitial fibrosis in diabetic rats.
Combined 2D-STE and MCE is sensitive for detecting left ventricular deformity and impaired microvascular perfusion in prediabetes and the early stage of diabetes mellitus. DAPA exerts a beneficial effect on protecting myocardial perfusion in diabetic rats.
本实验研究旨在通过综合超声心动图确定糖尿病大鼠心肌应变和微血管灌注的动态变化，同时评估达格列净（DAPA）的作用。
128只雄性Sprague-Dawley大鼠根据是否存在高脂饮食以及是否经链脲佐菌素诱导糖尿病并接受或不接受DAPA治疗随机分为四组（每组32只）。在第2、4、6和8周进行系列常规超声、二维斑点追踪超声心动图（2D-STE）和心肌对比超声心动图（MCE）检查，并测定左心室整体纵向应变（GLS）、心肌血流速度（MBFV）、心肌血流量（MBF）和心肌血容量（MBV）。所有动物在最后一次回声测量后立即处死进行组织病理学评估。
尽管各组在第2、4、6和8周的常规多普勒回声指标相似（P>0.05），但二维斑点追踪超声心动图和心肌对比超声心动图均检测到糖尿病大鼠在第8周时左心室GLS、MBFV、MBF和MBV降低（P<0.05）。糖尿病大鼠接受DAPA治疗后，这些指标在第6和8周时显著改善（P<0.05），达到非糖尿病对照组观察到的相似值。DAPA治疗与糖尿病大鼠心肌空泡化增加、微血管密度增加和间质纤维化减少有关。
二维斑点追踪超声心动图和心肌对比超声心动图联合应用对检测糖尿病前期和糖尿病早期左心室畸形及微血管灌注受损敏感。达格列净对保护糖尿病大鼠心肌灌注具有有益作用。
