Aldosterone mediates myocardial remodeling and fibrosis, as well as sodium retention and potassium loss at the distal tubules. The anti-aldosterone agent, spironolactone has been shown in RALES trial as an important neuro-hormonal antagonist in the treatment of heart failure. In this trial spironolactone 25 mg daily was compared with placebo in patients with advanced heart failure already receiving ACE inhibitors and diuretics and showed a 29 per cent reduction in mortality.