(1) Heart failure is diagnosed on the basis of both clinical symptoms and evaluation of cardiac function (preferably measured by echocardiography). Left ventricular dysfunction is defined as a left ventricular ejection fraction (LVEF) below 40%. The drugs of choice for chronic heart failure are certain angiotensin-converting-enzyme (ACE) inhibitors, some diuretics, some betablockers, and spironolactone. In one trial, spironolactone greatly reduced mortality at 24 months (35%, compared with 46% on placebo, p <0.001). (2) Eplerenone, a spironolactone derivative, is marketed for the treatment of left ventricular dysfunction in heart failure patients with recent myocardial infarction. (3) The EPHESUS study, a double-blind, placebo-controlled trial involving 6632 patients, showed a significant reduction in the overall mortality rate among patients with heart failure and recent myocardial infarction treated with eplerenone for 16 months (16.7% versus 14.4%; p = 0.008). This improvement was mainly due to a reduction in mortality during the first month of treatment. Eplerenone has not been compared with spironolactone, although the latter was known to be effective before the EPHESUS trial was conducted. (4) Severe hyperkalemia is frequent with eplerenone, occurring in 5.5% of patients. The risk of hyperkalaemia increases with renal failure and co-administration of potassium-sparing diuretics, ACE inhibitors, angiotensin II receptor antagonists and nonsteroidal antiinflammatory drugs. (5) In the short term, the incidence of gynecomastia in patients taking eplerenone seems to be low. (6) In patients who develop heart failure after myocardial infarction, an indirect comparison of available data favours spironolactone over eplerenone (better efficacy, lower risk of hyperkalemia). (7) In France, treatment with eplerenone is about 9 times more expensive than spironolactone. (8) Spironolactone remains the treatment of choice for patients with heart failure and incapacitating dyspnea despite ACE inhibitor and diuretic therapy. Eplerenone may possibly be useful for patients who have non severe heart failure after recent myocardial infarction.