title: Effects of diltiazem and esmolol on cycle length and spontaneous conversion of atrial fibrillation.
abstract: BACKGROUND
  Calcium channel blocking agents have been shown to prolong the duration of atrial fibrillation. This study compared the effects of intravenous diltiazem and esmolol on the cycle length and conversion rate of pacing-induced atrial fibrillation.
  
  
  RESULTS
  In 41 adults without structural heart disease, atrial fibrillation was induced by rapid atrial pacing. After 3 minutes, either diltiazem (n = 13), esmolol (n = 15), or saline (n = 13) was infused. In the diltiazem group, the atrial fibrillation cycle length shortened by a mean of 43 milliseconds and became significantly shorter than in the control group, while the atrial fibrillation cycle length in the esmolol group did not change. Spontaneous termination of atrial fibrillation occurred significantly less often in the diltiazem group (23%) than in the esmolol (67%, P < 0.05) or placebo groups (77%, P = 0.01).
  
  
  CONCLUSIONS
  Intravenous diltiazem shortens the atrial fibrillation cycle length and lowers the probability of spontaneous conversion of recent-onset atrial fibrillation to sinus rhythm. These results suggest that the use of diltiazem for acute rate control may unwittingly prolong the duration of recent-onset atrial fibrillation.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University Hospital Benjamin Franklin, Free University of Berlin, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Sticherling
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tada
authors.forename: William
authors.initials: W
authors.lastname: Hsu
authors.forename: Anton C
authors.initials: AC
authors.lastname: Bares
authors.forename: Hakan
authors.initials: H
authors.lastname: Oral
authors.forename: Frank
authors.initials: F
authors.lastname: Pelosi
authors.forename: Bradley P
authors.initials: BP
authors.lastname: Knight
authors.forename: S Adam
authors.initials: SA
authors.lastname: Strickberger
authors.forename: Fred
authors.initials: F
authors.lastname: Morady
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000503:physiopathology*; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology* / Q000627:therapeutic use; D004110:Diltiazem / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011412:Propanolamines / Q000494:pharmacology* / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D002121:Calcium Channel Blockers; D011412:Propanolamines; D004110:Diltiazem; C036604:esmolol