Left ventricular systolic dysfunction (LVSD) is a common complication of acute myocardial infarction (AMI) that occurs in approximately 30% of post-AMI patients, and results in a threefold increase in in-hospital and 6-month mortality, regardless of type of AMI. Post-AMI care has evolved to include early reperfusion, antiplatelet therapy, hydroxymethylglutaryl coenzyme A reductase inhibitors (stains), beta blockers, angiotentsin-converting enzyme inhibitors, and angiotensin receptor blockers. Despite these therapies, however, there is still an excess of sudden cardiac death (SCD), especially in patients with severe LVSD and in the first 30 days post-AMI. Aldosterone has been shown to be elevated in patients with post-AMI LVSD and to have deleterious effects on the myocardium, including endothelial dysfunction, collagen deposition, inflammation, apoptosis, and autonomic instability, leading to left ventricular remodeling and SCD. Aldosterone blockade with eplerenone has been shown to reduce mortality even in the presence of optimal post-AMI therapy in patients with post-AMI LVSD. Despite this, eplerenone is underutilized in real-world clinical practice. Care must be taken to follow renal function and potassium balance in patients treated with eplerenone.