Mineralocorticoid receptor antagonists for heart failure: a real life observational study

Aims. Mineralocorticoid receptor antagonists (MRA) have been demonstrated to improve outcomes in reduced ejection fraction heart failure patients (HFrEF). However, MRA added to conventional treatment may lead to worsening of renal function and hyperkalaemia. We investigated, in a population-based analysis, the long-term effects of MRA treatment in HFrEF patients. Methods and Results. We analyzed 6046 patients data included in the Metabolic Exercise Cardiac Kidney Index (MECKI) score data-set. Analysis was performed in patients treated (n=3163) and not treated (n=2883) with MRA. Study endpoint was composite of cardiovascular death, urgent heart transplantation or left ventricular assist device implantation. Ten years survival was analyzed through Kaplan Meier, compared by Log-Rank test and propensity score matching. At 10 years follow-up MRA not treated group had significantly lower number of events than MRA treated group (p<0.001).MRA treated patients had more severe HF (higher NYHA class and lower left ventricular ejection fraction, kidney function and peakVO2). At propensity score matching analysis performed on 1587 patients, MRA treated and not treated patients showed similar study endpoint values. Conclusion. In conclusion, MRA treatment does not affect the composite of cardiovascular death, urgent heart transplantation or left ventricular assist device implantation, in a real life setting. A meticulous patients follow-up, as done in trials, is likely needed to match the positive MRA-related benefits observed in clinical trials.