title: Angiotensin-converting enzyme inhibition or mineralocorticoid receptor blockade do not affect prevalence of atrial fibrillation in patients undergoing cardiac surgery.
abstract: OBJECTIVE
  This study tested the hypothesis that interruption of the renin-angiotensin system with either an angiotensin-converting enzyme inhibitor or a mineralocorticoid receptor antagonist will decrease the prevalence of atrial fibrillation after cardiac surgery.
  
  
  METHODS
  Randomized double-blind placebo-controlled study.
  
  
  METHODS
  University-affiliated hospitals.
  
  
  METHODS
  Four hundred forty-five adult patients in normal sinus rhythm undergoing elective cardiac surgery.
  
  
  METHODS
  One week to 4 days prior to surgery, patients were randomized to treatment with placebo, ramipril (2.5 mg the first 3 days followed by 5 mg/day, with the dose reduced to 2.5 mg/day on the first postoperative day only), or spironolactone (25 mg/day).
  
  
  METHODS
  The primary endpoint was the occurrence of electrocardiographically confirmed postoperative atrial fibrillation. Secondary endpoints included acute renal failure, hyperkalemia, the prevalence of hypotension, length of hospital stay, stroke, and death.
  
  
  RESULTS
  The prevalence of atrial fibrillation was 27.2% in the placebo group, 27.8% in the ramipril group, and 25.9% in the spironolactone group (p=.95). Patients in the ramipril (0.7%) or spironolactone (0.7%) group were less likely to develop acute renal failure than those randomized to placebo (5.4%, p=.006). Patients in the placebo group tended to be hospitalized longer than those in the ramipril or spironolactone group (6.8±8.2 days vs. 5.7±3.2 days and 5.8±3.4 days, respectively, p=.08 for the comparison of placebo vs. the active treatment groups using log-rank test). Compared with patients in the placebo group, patients in the spironolactone group were extubated sooner after surgery (576.4±761.5 mins vs. 1091.3±3067.3 mins, p=.04).
  
  
  CONCLUSIONS
  Neither angiotensin-converting enzyme inhibition nor mineralocorticoid receptor blockade decreased the primary outcome of postoperative atrial fibrillation. Treatment with an angiotensin-converting enzyme inhibitor or mineralocorticoid receptor antagonist was associated with decreased acute renal failure. Spironolactone use was also associated with a shorter duration of mechanical ventilation after surgery.
authors: Department of Anesthesiology, Division of Cardiology, Vanderbilt University School of Medicine, Nashville, TN, USA. mias.pretorius@vanderbilt.edu
authors: Mias
authors: M
authors: Pretorius
authors: Katherine T
authors: KT
authors: Murray
authors: Chang
authors: C
authors: Yu
authors: John G
authors: JG
authors: Byrne
authors: Frederic T
authors: FT
authors: Billings
authors: Michael R
authors: MR
authors: Petracek
authors: James P
authors: JP
authors: Greelish
authors: Steven J
authors: SJ
authors: Hoff
authors: Stephen K
authors: SK
authors: Ball
authors: Vineet
authors: V
authors: Mishra
authors: Simon C
authors: SC
authors: Body
authors: Nancy J
authors: NJ
authors: Brown
mesh_terms: D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D001281:Atrial Fibrillation / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D001794:Blood Pressure; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D004311:Double-Blind Method; D004562:Electrocardiography; D005260:Female; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D017257:Ramipril / Q000008:administration & dosage*; D018161:Receptors, Mineralocorticoid / Q000378:metabolism*; D012084:Renin-Angiotensin System / Q000187:drug effects; D013148:Spironolactone / Q000008:administration & dosage*
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D018161:Receptors, Mineralocorticoid; D013148:Spironolactone; D017257:Ramipril