[Impact of empagliflozin on peak oxygen uptake in HFmrEF patients: a randomized controlled trial].

Objective: To evaluate the impact of empagliflozin on peak oxygen uptake (VO2peak) in patients with heart failure with mildly reduced ejection fraction (HFmrEF). Methods: In this randomized controlled trial, consecutive HFmrEF patients admitted to the Department of Cardiology of China-Japan Friendship Hospital from September 2019 to October 2020 were screened, and randomly assigned to empagliflozin group (EG) or conventional group (CG) using a random number table. The enrolled patients were treated according to the guidelines, and patients in the empagliflozin group received additional empagliflozin (10 mg, once a day, orally) on top of the conventional treatment. The primary end points were VO2peak at 6 months after treatment, and the secondary end points included other parameters of cardiopulmonary exercise test (CPET), 6-minute walking distance, N-terminal B-type pro-natriuretic peptide (NT-proBNP) level, and Kansas City Cardiomyopathy Questionnaire (KCCQ) score. Results: A total of 112 patients were included (mean age 69 (57, 78) years, 84 male (75.0%)). There were 55 cases in CG group and 57 cases in EG group. There were no significant differences in baseline data including age, sex, body mass index, left ventricular ejection fraction, systolic blood pressure, heart rate, estimated glomerular filtration rate, glycosylated hemoglobin, hemoglobin, NT-proBNP, daily dose of tolasemi, combined medication, CPET parameters, the proportion of New York Heart Association heart function Ⅲ/Ⅳ, history of coronary heart disease, history of hypertension, history of diabetes (all P>0.05). At 6 months after treatment, VO2peak was significantly higher in EG group than in CG group(P=0.023). VE/VCO2 slope was significantly lower in EG group than in CG group(P=0.034). Oxygen uptake efficiency slope was significantly higher in EG group than in CG group(P=0.038). The level of NT-proBNP was significantly lower in EG group than in CG group(P=0.020). Six-minute walking distance was significantly higher in EG group than in CG group(P=0.037). KCCQ score was significantly higher in EG group than in CG group(P=0.048). Exercise oscillatory ventilation decreased in both groups (1 case in each group, P>0.05). Conclusion: Empagliflozin can significantly improve VO2peak in patients with HFmrEF.目的： 探讨恩格列净对射血分数轻度降低的心力衰竭（HFmrEF）患者峰值摄氧量（VO2peak）的影响。 方法： 该研究为随机对照试验。连续入选2019年9月至2020年10月就诊于中日友好医院心内科的HFmrEF患者，采集患者的基线临床资料。采用随机数字表法将患者分为恩格列净组和常规治疗组。根据指南对入选患者进行规范化药物调整，恩格列净组在常规治疗的基础上加用恩格列净（10 mg，每日1次，口服）。主要终点为治疗后6个月患者的VO2peak，次要终点包括心肺运动试验（CPET）的其他参数、6 min步行距离、N末端B型利钠肽原（NT-proBNP）水平以及堪萨斯城心肌病调查问卷（KCCQ）评分。 结果： 最终入选患者112例，年龄69（57，78）岁，男性84例（75.0%）。其中常规治疗组55例，恩格列净组57例，两组间年龄、性别、体重指数、左心室射血分数、收缩压、心率、估算的肾小球滤过率、糖化血红蛋白、血红蛋白、NT-proBNP、托拉塞米日剂量、合并用药、CPET各参数以及纽约心脏协会心功能Ⅲ/Ⅳ级、有冠心病病史、有高血压病史、有糖尿病病史患者所占比例差异均无统计学意义（P均>0.05）。治疗后6个月，恩格列净组患者的VO2peak高于常规治疗组（P=0.023），二氧化碳通气当量斜率水平低于常规治疗组（P=0.034），摄氧效率斜率高于常规治疗组（P=0.038）；NT-proBNP水平低于常规治疗组（P=0.020），6 min步行距离大于常规治疗组（P=0.037），KCCQ评分高于常规治疗组（P=0.048）。 结论： 恩格列净可改善HFmrEF患者的VO2peak。.