Eplerenone reduced total mortality by 15% and cardiovascular mortality by 17%, with a reduction in sudden cardiac death of 21%. Of those enrolled, 87% were receiving ACE inhibitors and 75% were receiving -blockers, indicating that aldosterone antagonist therapy pro- vides incremental benefit to these agents. Although spirono- lactone has not been studied specifically in ACS, this agent demonstrated a significant mortality benefit for patients with NewYork Heart Association (NYHA) class III or IV HF in the and it is also reasonable to use spironolactone for patients after ACS who meet EPHESUS criteria. Aldosterone antagonists should be avoided in patients with significantly elevated serum creatinine levels ( 2.5 mg/dL in men, 2.0 mg/dL in women) or elevated potassium levels ( 5.0 mEq/L) because there is a serious risk of hyperkalemia with the use of these agents in patients with an estimated cre- atinine clearance of <50 mL/min.176 Close clinical and labo- ratory follow-up is needed for patients receiving long-term treatment with aldosterone antagonists to mitigate the occur- rence and complications of hyperkalemia.207 Mineralocorticoid antagonists are underused among evi- dence-based medications after MI. This likely reflects appro- priate concerns about the risk for hyperkalemia with these agents. However, many patients can safely receive these highly effective and inexpensive agents with careful follow-up. Although thiazide and thiazide-type diuretics play a major role in the long-term control of BP, inACS, diuretics are used primar- ily for patients with evidence of increased filling pressures, pul- monary venous congestion, or HF. Particular caution is needed with regard to hypokalemia, which may precipitate arrhythmias Loop diuretics are preferred over thiazide and thia- zide-type diuretics for patients with ACS who have HF (NYHA class III or IV) or for patients with CKD and an estimated glo- merular filtration rate of <45 mL/min. 5.4. 