title: An evaluation of the change in electrocardiographic P-wave variables after acute caffeine ingestion in normal volunteers.
abstract: BACKGROUND
  Caffeine's effect on supraventricular dysrhythmias is poorly understood, and establishing a marker to predict atrial fibrillation may help to explain supraventricular dysrhythmias caused by caffeine.
  
  
  OBJECTIVE
  To evaluate the effects of caffeine (mean 6.1 mg/kg) on maximum P-wave duration and P-wave dispersion in normal volunteers.
  
  
  METHODS
  A randomised, double-blind, placebo-controlled, crossover study in 10 healthy volunteers at least 17 years of age at the University of Connecticut. Participants abstained from caffeinated products for at least 2 days before study initiation and were randomly allocated on different days to receive placebo or caffeine 400 mg. For each of the study phases, a baseline 12-lead electrocardiogram (ECG) was performed and a subsequent 12-lead ECG was performed 3 h after ingesting the study drug.
  
  
  RESULTS
  No significant changes were found within intra- or intergroup comparisons for any P-wave variables measured.
  
  
  CONCLUSIONS
  Single dose caffeine (400 mg) does not affect average P-wave duration, maximum P-wave duration or P-wave dispersion in normal individuals.
authors.affiliation: University of Connecticut School of Pharmacy, Storrs and Farmington, CT, USA.
authors.forename: M F
authors.initials: MF
authors.lastname: Caron
authors.forename: J
authors.initials: J
authors.lastname: Song
authors.forename: R
authors.initials: R
authors.lastname: Ammar
authors.forename: J
authors.initials: J
authors.lastname: Kluger
authors.forename: C M
authors.initials: CM
authors.lastname: White
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000139:chemically induced*; D002110:Caffeine / Q000009:adverse effects* / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000009:adverse effects* / Q000494:pharmacology*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D010919:Placebos
chemical_list: D000697:Central Nervous System Stimulants; D010919:Placebos; D002110:Caffeine