Abstract: Objective　To evaluate the changes in ventricular rate in patients with atrial fibrillation（AF） treated by Bisoprolol versus Metoprolol during the 6-minute walk test（6MWT）.Methods　This retrospective study was conducted in 50 AF patients and 42 controls with normal sinus rhythm from September 2015 to September 2017.All of them underwent two rounds of 6MWT，first without taking drugs，then took drugs〔28 AF patients took Metoprolol（Metoprolol-treated AF subgroup） and 22 used Bisoprolol（Bisoprolol-treated AF subgroup），23 controls used Metoprolol（Metoprolol-treated control subgroup），and 19 took Bisoprolol（Bisoprolol-treated control subgroup）〕.The changes in ventricular rate in all the participants during the 6MWT under these two conditions were analyzed.And based on this，the impact of Metoprolol versus Bisoprolol on ventricular rate was compared.Results　During the 6MWT，the ventricular rate of all participants first increased but later decreased under the conditions of taking drugs or not.In general，the controls reached their maximal ventricular rate when the 6MWT was conducted for 5 minutes，while the AF patients reached their maximal ventricular rate when the 6MWT was conducted for 3 minutes，under the conditions of without taking drugs.The controls taking Metoprolol and those taking Bisoprolol attained their maximal ventricular rate when the 6MWT was conducted for 5，6 minutes，respectively.For AF patients using Metoprolol and those using Bisoprolol，the mean maximal ventricular rate was attained when the 6MWT was conducted for 3，5 minutes，respectively.5 minutes after the end of the 6MWT，the mean ventricular rates of controls taking Metoprolol and those taking Bisoprolol basically recovered to the baseline level without significant difference（P>0.05）.However，the mean ventricular rates of the AF patients using Metoprolol and those using Bisoprolol did not recover to the baseline level and showed significant difference（P<0.05）.Conclusion　Compared with Metoprolol，Bisoprolol produced a stronger impact on decreasing the maximal ventricular rate during the 6MWT，and it delayed the reappearance of the maximal ventricular rate，indicating that it may have greater potential for ventricular rate control.

Key words: Atrial fibrillation, Bisoprolol, Metoprolol, 6-minute walk test, Ventricular rate

摘要： 目的　探讨比索洛尔与美托洛尔对心房颤动（房颤）患者活动过程中心室率影响的差异。方法　根据药物使用种类及时间进行分组，回顾性分析2015年9月—2017年9月42例窦性心律患者（23例使用美托洛尔，19例使用比索洛尔）和50例持续性房颤患者（28例使用美托洛尔，22例使用比索洛尔）在6 min步行试验过程中的心室率变化情况，从而分析比索洛尔和美托洛尔对心室率的不同作用特点。结果　所有患者在使用药物前后，活动过程中心室率变化均经历了先上升再下降的过程。使用药物前，窦性心律组在活动过程中的最大心室率出现在第5分钟，房颤组出现在第3分钟；使用美托洛尔后，窦性心律组患者活动过程中的最大心室率仍出现在第5分钟，房颤组患者活动过程中的最大心室率仍出现在第3分钟；使用比索洛尔后，窦性心律组患者活动过程中的最大心室率延迟出现在第6分钟，房颤组患者活动过程中的最大心室率延迟出现在第5分钟。窦性心律组，使用两种药物的患者休息5 min后心室率与活动前比较，差异无统计学意义（P>0.05）；房颤组，使用两种药物的患者休息5 min后心室率与活动前比较，差异有统计学意义（P<0.05）。结论　较之于美托洛尔，比索洛尔降低患者活动过程中最大心室率方面的作用更明显；比索洛尔可能具有延迟患者活动过程中心室率峰值再出现的作用，可能具有更为明显的心室率控制潜能。

关键词: 心房颤动, 比索洛尔, 美托洛尔, 6 min步行试验, 心室率