• Mias Pretorius, Katherine T Murray, Chang Yu, John G Byrne, Frederic T Billings, Michael R Petracek, James P Greelish, Steven J Hoff, Stephen K Ball, Vineet Mishra, Simon C Body, and Nancy J Brown.
• Department of Anesthesiology, Division of Cardiology, Vanderbilt University School of Medicine, Nashville, TN, USA. mias.pretorius@vanderbilt.edu
• Crit. Care Med.. 2012 Oct 1;40(10):2805-12.

ObjectiveThis 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.DesignRandomized double-blind placebo-controlled study.SettingUniversity-affiliated hospitals.PatientsFour hundred forty-five adult patients in normal sinus rhythm undergoing elective cardiac surgery.InterventionsOne 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).MeasurementsThe 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.Main ResultsThe 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).ConclusionsNeither 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.

26 keywords...

hide…