Review article: eplerenone: an underused medication?

The Effectiveness of Eplerenone vs Spironolactone on Left Ventricular Systolic Function, Hospitalization and Cardiovascular Death in Patients With Chronic Heart Failure-HFrEF

Background

Heart failure remains one of the most prevalent clinical syndromes associated with significant morbidity and mortality. According to current guidelines, the prescription of a MRA is recommended to reduce the risk of HF hospitalization and death in all patients with symptomatic heart failure and no contraindications for this therapy.

Objective

The aim of our study was to determine the efficacy of eplerenone vs. spironolactone on left ventricular systolic function by measuring left ventricle ejection fraction (LVEF) in patients with chronic heart failure, especially their effect on preventing hospitalization, reducing mortality, and improving clinical status among patients with chronic HF.

Methods

From June 2021 to June 2022, the study was a randomized, prospective clinical trial single blind study. A total of 142 patients of chronic heart failure with reduced ejection fraction were selected by random sampling. Each patient was randomly allocated into either of the two groups and was continued receiving treatment with either spironolactone (Spiron-HF group) or eplerenone (Epler-HF group). Patients in Epler-HF group were compared with an arm of the same size and matched by age and gender patients in Spiron-HF group for management of chronic HFrEF. Each patient was evaluated clinically, biochemically, and echocardiographically at the beginning of treatment (baseline) after 6 months and at the end of 12th month. Echocardiography was performed to find out change in left ventricular systolic function.

Results

After 12 months of treatment, significant improvement of left ventricular ejection fraction was observed in eplerenone treated arm (37.9 ± 3.8 ± 4.6 in Spiron-HF group versus 40.1 ± 5.7 in Epler-HF group; P < 0.05). A significant reduction in left ventricular end-systolic volume (6.3 ± 2.5ml in Spiron-HF versus 17.8± 4.4ml in Epler-HF group; P < 0.05) and left ventricular systolic diameter volume (2.7 ± 0.5ml in Spiron-HF versus 6.7 ± 0.2ml in Epler-HF group; P < 0.05), occurred after 12 months of treatment. Left ventricular global longitudinal strain (LV GLS) was significantly improved in Epler-HF group compared with Spiron-HF group (0.6 ± 0.4 versus 3.4 ± 0.9; P < 0.05). There were no significant differences observed in reduction of left ventricular end-diastolic volume (2.2 ± 0.5 ml versus 4.7 ± 1.1ml; P =0.103) and left ventricular diastolic diameter (1.2 ± 0.6 versus 1.7 ± 0.3; P=0.082) in both arms. The effects of both MRA agents spironolactone and eplerenone on the primary composite outcome, each of the individual mortality and hospital admission outcomes are shown in Figure 1 and 2. Patients of the Epler-HF group showed statistically significant lower cardiovascular mortality (HR 0.53; 95% CI 0.34-0.82; p= 0.007) and all-cause mortality (HR 0.64; 95% CI 0.44-0.93; p= 0.022) than patients of the Spiron-HF group. The statistical analysis did not show a statistically significant difference between Epler -HF and Spiron-HF study groups regarding the risk of the primary composite outcome; cardiovascular death or hospitalization due to HF (Hazard Ratio (HR) eplerenone vs. spironolactone = 0.95; 95% Confidence Interval (CI) 0.73- 1.27; p= 0.675).

Conclusion

Our study has demonstrated favorable effects of eplerenone on cardiac remodeling parameters and reduction of cardiovascular mortality and all-cause mortality compared with spironolactone in the treatment of HFrEF. The ability of eplerenone to effectively block the mineralocorticoid receptor while minimizing side effects and a significant reduction in the risk of hospitalization and cardiovascular death confirms its key role in the treatment of patients with chronic HFrEF.

Mineralocorticoid Receptor Antagonists in Diabetic Kidney Disease

Diabetes mellitus is a global health issue and main cause of chronic kidney disease. Both diseases are also linked through high cardiovascular morbidity and mortality. Diabetic kidney disease (DKD) is present in up to 40% of diabetic patients; therefore, prevention and treatment of DKD are of utmost importance. Much research has been dedicated to the optimization of DKD treatment. In the last few years, mineralocorticoid receptor antagonists (MRA) have experienced a renaissance in this field with the development of non-steroidal MRA. Steroidal MRA have known cardiorenal benefits, but their use is limited by side effects, especially hyperkalemia. Non-steroidal MRA still block the damaging effects of mineralocorticoid receptor overactivation (extracellular fluid volume expansion, inflammation, fibrosis), but with fewer side effects (hormonal, hyperkalemia) than steroidal MRA. This review article summarizes the current knowledge and newer research conducted on MRA in DKD.

Mineralocorticoid receptor antagonists, a class beyond spironolactone--Focus on the special pharmacologic properties of eplerenone

The renin-angiotensin-aldosterone system can be blocked at specific levels by using different classes of pharmacologic agents, including angiotensin-converting-enzyme inhibitors, angiotensin II receptor blockers and mineralocorticoid receptor antagonists. Broad use of the latter, such as spironolactone, has been limited by significant incidence of gynecomastia and other sex-related adverse effects. These problems can be overcome with use of eplerenone, a selective mineralocorticoid receptor antagonist. Eplerenone has been specifically developed to bind selectively to the mineralocorticoid receptors in order to minimize binding to the progesterone and androgen receptors. In the last decade, multiple scientific evidences have been accumulated showing the efficacy and safety of the drug in multiple clinical conditions, including heart failure and arterial hypertension. Eplerenone is generally well tolerated, with the most frequent adverse event being hyperkalemia, with sexual adverse events (i.e. gynecomastia) being more uncommon, due to the selectivity of eplerenone. This review focuses on the pharmacodynamic and pharmacokinetic properties of eplerenone, thus providing the scientific basis to fully understand drug-to-drug interactions, in particular, and its efficacy and tolerability, in general. Noteworthy, the activity of eplerenone in special conditions and different patient populations is summarized.

Linking the beneficial effects of current therapeutic approaches in diabetes to the vascular endothelin system

The rising epidemic of diabetes worldwide is of significant concern. Although the ultimate objective is to prevent the development and find a cure for the disease, prevention and treatment of diabetic complications is very important. Vascular complications in diabetes, or diabetic vasculopathy, include macro- and microvascular dysfunction and represent the principal cause of morbidity and mortality in diabetic patients. Endothelial dysfunction plays a pivotal role in the development and progression of diabetic vasculopathy. Endothelin-1 (ET-1), an endothelial cell-derived peptide, is a potent vasoconstrictor with mitogenic, pro-oxidative and pro-inflammatory properties that are particularly relevant to the pathophysiology of diabetic vasculopathy. Overproduction of ET-1 is reported in patients and animal models of diabetes and the functional effects of ET-1 and its receptors are also greatly altered in diabetic conditions. The current therapeutic approaches in diabetes include glucose lowering, sensitization to insulin, reduction of fatty acids and vasculoprotective therapies. However, whether and how these therapeutic approaches affect the ET-1 system remain poorly understood. Accordingly, in the present review, we will focus on experimental and clinical evidence that indicates a role for ET-1 in diabetic vasculopathy and on the effects of current therapeutic approaches in diabetes on the vascular ET-1 system.

Cardiac hypertrophy and fibrosis in the metabolic syndrome: a role for aldosterone and the mineralocorticoid receptor

Obesity and hypertension, major risk factors for the metabolic syndrome, render individuals susceptible to an increased risk of cardiovascular complications, such as adverse cardiac remodeling and heart failure. There has been much investigation into the role that an increase in the renin-angiotensin-aldosterone system (RAAS) plays in the pathogenesis of metabolic syndrome and in particular, how aldosterone mediates left ventricular hypertrophy and increased cardiac fibrosis via its interaction with the mineralocorticoid receptor (MR). Here, we review the pertinent findings that link obesity with elevated aldosterone and the development of cardiac hypertrophy and fibrosis associated with the metabolic syndrome. These studies illustrate a complex cross-talk between adipose tissue, the heart, and the adrenal cortex. Furthermore, we discuss findings from our laboratory that suggest that cardiac hypertrophy and fibrosis in the metabolic syndrome may involve cross-talk between aldosterone and adipokines (such as adiponectin).