title: Use of beta-blockers and effects on heart rate and blood pressure post-acute coronary syndromes: are we on target?
abstract: BACKGROUND
  beta-blockers have been shown to benefit patients after myocardial infarction by decreasing mortality, sudden cardiac death, and reinfarction. Although beta-blockers are recommended for all patients with acute coronary syndromes (ACS) without contraindications, a target heart rate (HR) is recommended only for patients with unstable angina/non ST-elevation myocardial infarction. A contemporary series documenting trends in beta-blocker usage and achieved HR and blood pressures (BP) is not available. The study objectives were to monitor trends in HR and BP in relation to beta-blocker use in a contemporary series of patients with ACS.
  
  
  METHODS
  In this observational study, 300 consecutive patients with proven ACS had HR and BP values collected hourly from admission until hospital discharge and averaged at multiple intervals throughout hospital stay. Data on baseline demographic characteristics, beta-blocker doses, and titration schedules, procedures performed, cardiac regimens, concurrent medical issues, and contraindications to therapy were collected.
  
  
  RESULTS
  Only 5.3% achieved an average HR of 50 to 60 beat/min throughout the hospital stay. Overall, the average HR was 74 beat/min and average BP was 115/64 mm Hg. Admission daily doses of metoprolol averaged 58 mg compared to discharge daily doses of 88 mg; only 52% of patients had dosage increases.
  
  
  CONCLUSIONS
  Although effective levels of BP were maintained during hospitalization for an ACS, target HRs were generally not achieved. Future studies are needed to determine the relationship between treatment objectives and clinical outcomes in the present era of ACS management.
authors.affiliation: Division of Cardiovascular Medicine, UMass-Memorial Medical Center, Worcester, MA 01655, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Herman
authors.forename: Jennifer
authors.initials: J
authors.lastname: Donovan
authors.forename: Maichi
authors.initials: M
authors.lastname: Tran
authors.forename: Brigid
authors.initials: B
authors.lastname: McKenna
authors.forename: Joel M
authors.initials: JM
authors.lastname: Gore
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Goldberg
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Tighe
mesh_terms: D054058:Acute Coronary Syndrome / Q000188:drug therapy* / Q000503:physiopathology*; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000494:pharmacology* / Q000627:therapeutic use; D008875:Middle Aged
chemical_list: D000319:Adrenergic beta-Antagonists; D008790:Metoprolol