Association Between Mineralocorticoid Receptor Antagonist Use and Outcome in Myocardial Infarction Patients With Heart Failure

Background There are no studies of mineralocorticoid receptor antagonist ( MRA ) treatment examining outcome in unselected real‐life patients with myocardial infarction ( MI ) and heart failure ( HF ). There is uncertainty regarding effects of MRA in relation to left ventricular ejection fraction ( LVEF ) and chronic kidney disease ( CKD ). The aim was to assess MRA use and compare outcomes in MI patients with HF in relation to LVEF and CKD . Methods and Results Patients with MI and HF registered in the Swedish myocardial infarction registry, SWEDEHEART , 2005–2014, were included. Associations between MRA use and all‐cause mortality up to 3 years were assessed with multivariable Cox regression, stratified by EF groups and presence of CKD (estimated glomerular filtration rate <60 mL/min per 1.73 m 2 ). Of 45 071 patients with MI and HF , 4470 (9.9%) received MRA . Those with HF and LVEF <40% more often had MRA (19.6%) compared with those with LVEF 40% to 49% (9.1%) or LVEF ≥50% (4.7%). 8.6% of patients with CKD received MRA . After adjustment, MRA use was associated with lower mortality in those with LVEF <40% (hazard ratio [95% confidence interval] 0.81 [0.75–0.88]) and LVEF 40% to 49% (0.88 [0.75–1.03]) but not in those with LVEF ≥50% (1.29 [1.09–1.53]), with significant interaction between MRA and LVEF ( P <0.0001). The association between MRA use and mortality was similar in those without (0.96 [0.88–1.05]) and with (0.92 [0.85–0.99]) CKD . Conclusions In patients with MI and HF , MRA use was associated with better long‐term survival in patients with LVEF <40% but not in those with LVEF ≥50%, while the mortality risk was similar in MRA ‐treated patients with or without CKD .