Low-dose eplerenone decreases left ventricular mass in treatment-resistant hypertension

Background: Mineralocorticoid receptor antagonists are increasingly used in patients with treatment-resistant hypertension (TRH). There is experimental evidence for blood pressure (BP) independent effects of mineralocorticoid receptor blockade on cardiovascular target organ damage. We hypothesized that low-dose eplerenone (50 mg) will reduce left ventricular mass (LVM) beyond its BP-lowering effects. Methods: We performed a randomized, double-blind, placebo-controlled, parallel group study in 51 patients with TRH. Patients were allocated to receive either eplerenone 50 mg or placebo for 6 months, while other antihypertensive agents could be added in both groups to achieve a BP target of less than 140/90 mmHg. LVM was assessed by MRI before and after treatment. Results: Baseline office BP was similar in the eplerenone and the placebo group (166 +/- 21/91 +/- 15 versus 159 +/- 19/ 94 +/- 8mmHg, n.s.). BP was similarly reduced in the eplerenone versus the placebo group (-35 +/- 20/-15 +/- 11 versus -30 +/- 19/- 13 +/- 7 mmHg, n.s.). However, LVM was reduced only in the eplerenone group (from 155 +/- 33 to 136 +/- 33 g, P< 0.001), but not in the placebo group (152 +/- 32 versus 148 +/- 38 g, P = 0.45). Conclusions: Despite similar BP-lowering, only patients with TRH who were allocated to eplerenone experienced a reduction of LVM. Thus, our data suggest that in patients with TRH, mineralocorticoid receptor antagonists should be used preferentially in order to achieve an effective reduction of LVM along with the improvement of BP control.