Mineralocorticoid receptor antagonists in patients with acute myocardial infarction - A systematic review and meta-analysis of randomized trials.

BACKGROUND: Although mineralocorticoid antagonists (MRAs) reduce mortality in patients with heart failure complicating myocardial infarction (MI), it is unclear if they could be beneficial to all patients with MI. To evaluate the utility of MRAs in MI patients, we performed a systematic review and meta-analysis.

METHODS: MEDLINE, EMBASE, and Cochrane CENTRAL were searched from 1965 to June 2016. Conference abstracts were searched from 2000 to June 2016. Randomized trials evaluating the effect of MRA after MIs were included. Two reviewers independently extracted data and assessed study quality. Data were combined using fixed-/random-effects models.

RESULTS: Eleven randomized clinical trials (N = 11,258) were included; 1 trial (N = 6,642) included patients with apparent heart failure (Killip class III-IV). Administration of MRA versus placebo or standard therapy (no-MRA) after MI reduced overall and cardiovascular mortality (odds ratio [OR] 0.82, 95% CI 0.73-0.93, P = .002, and OR 0.82, 95% CI 0.71-0.93, P = .003, respectively; I2 for both = 0%). In the subgroup of trials with patients with heart failure, the mortality was 14.4% in MRA group versus 16.7% in no-MRA group (OR 0.84, 95% CI 0.73-0.96), and among those without heart failure, it was 2.5% with MRA versus 3.5% without MRA (OR 0.72, 95% CI 0.51-1.02, P for interaction = .43). Patients receiving MRA had fewer new or worsening heart failure events (OR 0.74, 95% CI 0.66-0.84, P < .0001; I2 = 14%). Nevertheless, MRA therapy increased risk for hyperkalemia (≥5.5 mmol/L) (OR 2.52, 95% CI 1.36-4.65, P = .003; I2 = 63%).

CONCLUSIONS: Administration of MRA may reduce mortality after acute MI. However, this is largely based on post-MI patients with heart failure. Further data are needed in MI patients without heart failure.