title: Heart rate distribution and predictors of resting heart rate after initiation of beta-blocker treatment in patients with coronary artery disease: REsults of Sympathetic Evaluation And Research of China (RESEARCH) study.
abstract: BACKGROUND
  The importance of heart rate as secondary prevention strategies for patients with coronary artery disease (CAD) is emphasized by multiple guidelines. However, limited information is available on the heart rate distribution and the change patterns of resting heart rate when initiating beta-blocker therapy among Chinese patients with CAD.
  
  
  METHODS
  The REsults of Sympathetic Evaluation And Research of China (RESEARCH) study is a multi-centre, prospective, observational study involving 147 centers in 23 cities across China. All eligible beta-blocker naive patients were prescribed with metroprolol succinate. Initial dosage and target heart rate were selected at the discretion of their physicians in charge according to their usual institutional practice. The heart rate distribution and the change patterns of resting heart rate after initiation of beta-blocker therapy were observed.
  
  
  RESULTS
  The majority of patients (63.6%) were prescribed with 47.5 mg metroprolol succinate. At baseline, there were only 17.4% of patients whose heart rate was less than 70 beats per minute, and the proportion reached 42.5% and 79.1%, one month and two months after initiation of beta-blockers, respectively. Multivariate linear regression analysis showed that baseline heart rate (B = 0.900, SE = 0.006, t = 141.787, P < 0.0001) and the dosage (B = -0.007, SE = 0.002, t = -3.242, P = 0.001) were independent predictors of resting heart rate 2 months after beta-blocker therapy.
  
  
  CONCLUSIONS
  Resting heart rate is not optimally controlled in a broadly representative cohort of Chinese outpatients with CAD even after initiation of β-blocker therapy, and baseline heart rate and the dosage of beta-blocker are both independent predictors of resting heart rate after β-blocker therapy.
authors.affiliation: Department of Cardiology, Anzhen Hospital, Capital Medical University, Beijing 100029, China.
authors.forename: Ying-Xin
authors.initials: YX
authors.lastname: Zhao
authors.forename: Yue-Ping
authors.initials: YP
authors.lastname: Li
authors.forename: Fei
authors.initials: F
authors.lastname: Gao
authors.forename: Han-Ying
authors.initials: HY
authors.lastname: Ma
authors.forename: Zhi-Jian
authors.initials: ZJ
authors.lastname: Wang
authors.forename: Hong-Ya
authors.initials: HY
authors.lastname: Han
authors.forename: Hua
authors.initials: H
authors.lastname: Shen
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Zhou
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000368:Aged; D002681:China; D003324:Coronary Artery Disease / Q000188:drug therapy* / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists