title: Double blind randomised controlled trial of effect of metoprolol on myocardial ischaemia during endoscopic cholangiopancreatography.
abstract: OBJECTIVE
  To evaluate the effect of metoprolol, a beta adrenergic blocking drug, on the occurrence of myocardial ischaemia during endoscopic cholangiopancreatography.
  
  
  METHODS
  Double blind, randomised, controlled trial.
  
  
  METHODS
  University Hospital.
  
  
  METHODS
  38 (two groups of 19) patients scheduled for endoscopic cholangiopancreatography.
  
  
  METHODS
  Metoprolol 100 mg or placebo as premedication two hours before endoscopy.
  
  
  METHODS
  Heart rate, arterial oxygen saturation by continuous pulse oximetry, ST segment changes during endoscopic cholangiopancreatography (an ST segment deviation > 1 mV was defined as myocardial ischaemia), electrocardiogram monitored continuously with a Holter tape recorder.
  
  
  RESULTS
  All patients had increased heart rate during endoscopy compared with rate before endoscopy, but heart rate during endoscopy was significantly lower in the metoprolol group compared with the placebo group (P = 0.0002). Twenty one patients (16 placebo, 5 metoprolol; P = 0.0008) developed tachycardia (heart rate > 100/min) during the procedure, and 11 patients (10 placebo, 1 metoprolol; P = 0.003) developed myocardial ischaemia. One patient in the placebo group had an acute inferolateral myocardial infarction. In the 10 other patients with signs of myocardial ischaemia during endoscopy the ST deviation disappeared when the endoscope was retracted. In all patients myocardial ischaemia was related to increases in heart rate, and 10 of the 11 patients had tachycardia coherent with myocardial ischaemia.
  
  
  CONCLUSIONS
  Metoprolol prevented myocardial ischaemia during endoscopic cholangiopancreatography, probably through lowering the heart rate. Thus, tachycardia seems to be a key pathogenic factor in the development of myocardial ischaemia during endoscopy.
authors.affiliation: Department of Surgery, Sundby Hospital, Copenhagen, Denmark.
authors.forename: J
authors.initials: J
authors.lastname: Rosenberg
authors.forename: H
authors.initials: H
authors.lastname: Overgaard
authors.forename: M
authors.initials: M
authors.lastname: Andersen
authors.forename: V
authors.initials: V
authors.lastname: Rasmussen
authors.forename: S
authors.initials: S
authors.lastname: Schulze
mesh_terms: D000318:Adrenergic beta-Agonists / Q000627:therapeutic use*; D002760:Cholangiopancreatography, Endoscopic Retrograde; D004311:Double-Blind Method; D015716:Electrocardiography, Ambulatory; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000627:therapeutic use*; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000517:prevention & control*; D010092:Oximetry; D010100:Oxygen / Q000097:blood; D011292:Premedication; D013610:Tachycardia / Q000517:prevention & control
chemical_list: D000318:Adrenergic beta-Agonists; D008790:Metoprolol; D010100:Oxygen