Eplerenone Improves Vascular Endothelial Function in Patients with Primary Aldosteronism: A Pilot Study

Primary aldosteronism (PA) is associated with a high risk of cardiovascular complications. Large-scale clinical studies have demonstrated that mineralocorticoid receptor antagonists (MRA) exhibit organ-protective effects and improve the prognosis of patients with heart failure and myocardial infarction, and daily clinical practice suggests that MRA seem to improve vascular endothelial dysfunction. In this pilot study, we treated 10 PA patients with eplerenone for 3 months. We used Endo-PAT to evaluate the effects of MRA on vascular endothelial function and analyzed the data for correlative factors. The primary outcome measure, the reactive hyperemia index (RHI), was 1.71 before therapy and increased significantly to 2.21. Univariate analysis showed a significant correlation between the rate of change in RHI and that in plasma renin activity (PRA). Since plasma aldosterone concentration increases during MRA therapy, PRA may be the best marker for selecting the most appropriate dose of MRA. PRA can potentially be used for adjusting the dose of MRA, in addition to adjusting blood pressure and serum potassium level.