Eplerenone: the evidence for its place in the treatment of heart failure after myocardial infarction

INTRODUCTION: Heart failure is a frequent complication after acute myocardial infarction (MI) and carries a poor prognosis. Current treatments inhibit the renin-angiotensin-aldosterone system but suppression of aldosterone may be incomplete. The aldosterone antagonist spironolactone has been shown to improve survival in patients with chronic, severe heart failure. Eplerenone is a selective aldosterone antagonist expected to have a lower incidence of hormonal side effects than spironolactone. AIMS: To assess the evidence on the therapeutic value of eplerenone for treatment of heart failure in adults. EVIDENCE REVIEW: The evidence base consists of one large double-blind placebo-controlled multicenter randomized trial in over 6000 patients with postmyocardial infarction (MI) heart failure, comparing eplerenone plus standard therapy with placebo plus standard therapy. All the main outcomes were patient-oriented. Evidence from this trial shows that eplerenone improves survival and reduces cardiovascular hospitalization/mortality, compared with standard treatment alone. The incidence of hormonal side effects is no greater than with placebo. The risk of hyperkalemia is significantly increased, especially in patients with low creatinine clearance. Eplerenone was both more effective and more costly than standard treatment alone. The cost-effectiveness ratio has been estimated at $US10 402–21 876 per life-year gained. PLACE IN THERAPY: Eplerenone reduces mortality compared with current treatment alone in patients with post-MI heart failure, at additional cost. Direct comparative evidence is needed to assess its efficacy versus spironolactone. It may be valuable in patients who are intolerant to the hormonal side effects of spironolactone.