Department of Physiology-HeartOtago, Otago School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.
Department of Medicine-HeartOtago, Dunedin School of Medicine, Dunedin Hospital, Dunedin, New Zealand.
Physiol Rep. 2020 Mar;8(5):e14394. doi: 10.14814/phy2.14394.
Increasing cohorts of patients present with diabetic cardiomyopathy, and with no targeted options, treatment often rely on generic pharmaceuticals such as β-blockers. β-blocker efficacy is heterogenous, with second generation β-blocker metoprolol selectively inhibiting β -AR, while third generation β-blocker carvedilol has α -AR inhibition, antioxidant, and anti-apoptotic actions alongside nonselective β-AR inhibition. These additional properties have led to the hypothesis that carvedilol may improve cardiac contractility in the diabetic heart to a greater extent than metoprolol. The present study aimed to compare the efficacy of metoprolol and carvedilol on myocardial function in animal models and cardiac tissue from patients with type 2 diabetes and preserved ejection fraction.
Echocardiographic examination of cardiac function and assessment of myocardial function in isolated trabeculae was carried out in patients with and without diabetes undergoing coronary artery bypass grafting (CABG) who were prescribed metoprolol or carvedilol. Equivalent measures were undertaken in Zucker Diabetic Fatty (ZDF) rats following 4 weeks treatment with metoprolol or carvedilol.
Patients receiving carvedilol compared to metoprolol had no difference in cardiac function, and no difference was apparent in myocardial function between β-blockers. Both β-blockers similarly improved myocardial function in diabetic ZDF rats treated for 4 weeks, without significantly affecting in vivo cardiac function.
Metoprolol and carvedilol were found to have no effect on cardiac function in type 2 diabetes with preserved ejection fraction, and were similarly effective in preventing myocardial dysfunction in ZDF rats.
越来越多的患者患有糖尿病性心肌病，由于没有针对性的治疗方法，治疗通常依赖于β受体阻滞剂等普通药物。β受体阻滞剂的疗效存在差异，第二代β受体阻滞剂美托洛尔选择性抑制β-AR，而第三代β受体阻滞剂卡维地洛具有α-AR 抑制、抗氧化和抗凋亡作用，以及非选择性β-AR 抑制。这些额外的特性导致了这样一种假设，即卡维地洛可能比美托洛尔更能改善糖尿病心脏的心肌收缩力。本研究旨在比较美托洛尔和卡维地洛在 2 型糖尿病和射血分数保留的动物模型和心脏组织中的心肌功能的疗效。
对接受冠状动脉旁路移植术（CABG）的 2 型糖尿病患者和无糖尿病患者进行超声心动图检查，评估其心脏功能，并评估接受美托洛尔或卡维地洛治疗的患者的心肌功能。在接受 4 周美托洛尔或卡维地洛治疗的 Zucker 糖尿病肥胖（ZDF）大鼠中进行了等效测量。
与接受美托洛尔治疗的患者相比，接受卡维地洛治疗的患者的心脏功能没有差异，两种β受体阻滞剂之间的心肌功能也没有差异。两种β受体阻滞剂在接受 4 周治疗的糖尿病 ZDF 大鼠中均同样改善了心肌功能，而对体内心脏功能没有显著影响。
美托洛尔和卡维地洛对射血分数保留的 2 型糖尿病患者的心脏功能没有影响，对 ZDF 大鼠预防心肌功能障碍同样有效。
