Mineralocorticoid Receptor Antagonist Use in Heart Failure With Reduced Ejection Fraction and End-Stage Renal Disease Patients on Dialysis: A Literature Review

A review regarding the article 'Mineralocorticoid receptor antagonists in heart failure with reduced ejection fraction: a network meta-analysis of 32 randomized trials'

Heart failure (HF) is a prevalent clinical syndrome characterized by significant morbidity and is often precipitated by impaired left ventricular myocardial function. The condition can be categorized into two primary forms based on the ejection fraction (EF): Heart failure with preserved ejection fraction (HFpEF) and Heart failure with reduced ejection fraction (HFrEF). Evidence-based treatments for HF have been instrumental in reducing morbidity and mortality, particularly in patients with HFrEF. Mineralocorticoid receptor antagonists (MRAs) represent a cornerstone in the pharmacological management of HF, with a strong indication for use in HFrEF. Notably, pharmacological nuances exist among MRAs, which may influence therapeutic decision-making for individual patients. Moreover, MRAs have been shown to enhance heart rate variability and improve cardiac sympathetic nervous system function in HF patients. Spironolactone, an MRA, has been a pivotal agent in the clinical management of HFrEF since its introduction. However, its use has been tempered by certain side effects, including gynecomastia and hyperkalemia, leading to considerable discontinuation rates among patients. To address these challenges, numerous randomized clinical trials (RCTs) have been conducted to assess the efficacy and safety profiles of alternative steroidal and non-steroidal MRAs. Eplerenone, a steroidal MRA introduced subsequent to spironolactone, has demonstrated efficacy with a more favorable side effect profile.

The recent advance and prospect of natural source compounds for the treatment of heart failure

Heart failure is a continuously developing syndrome of cardiac insufficiency caused by diseases, which becomes a major disease endangering human health as well as one of the main causes of death in patients with cardiovascular diseases. The occurrence of heart failure is related to hemodynamic abnormalities, neuroendocrine hormones, myocardial damage, myocardial remodeling etc, lead to the clinical manifestations including dyspnea, fatigue and fluid retention with complex pathophysiological mechanisms. Currently available drugs such as cardiac glycoside, diuretic, angiotensin-converting enzyme inhibitor, vasodilator and β receptor blocker etc are widely used for the treatment of heart failure. In particular, natural products and related active ingredients have the characteristics of mild efficacy, low toxicity, multi-target comprehensive efficacy, and have obvious advantages in restoring cardiac function, reducing energy disorder and improving quality of life. In this review, we mainly focus on the recent advance including mechanisms and active ingredients of natural products for the treatment of heart failure, which will provide the inspiration for the development of more potent clinical drugs against heart failure.

Overview of research progress on the association of dietary potassium intake with serum potassium and survival in hemodialysis patients, does dietary potassium restriction really benefit hemodialysis patients?

For the general population, increasing potassium intake can reduce the incidence of cardiovascular and cerebrovascular diseases. However, since hyperkalemia is a common and life-threatening complication in maintenance hemodialysis patients, which can increase the risk of malignant arrhythmia and sudden death, the current mainstream of management for hemodialysis patients is dietary potassium restriction in order to prevent hyperkalemia. Hemodialysis patients are usually advised to reduce dietary potassium intake and limit potassium-rich fruits and vegetables, but there is limited evidence to support this approach can reduce mortality and improve quality of life. There is still no consistent conclusion on the association between dietary potassium intake and serum potassium and survival in hemodialysis patients. According to the current small observational studies, there was little or even no association between dietary potassium intake and serum potassium in hemodialysis patients when assurance of adequate dialysis and specific dietary patterns (such as the plant-based diet mentioned in the article) are being followed, and excessive dietary potassium restriction may not benefit the survival of hemodialysis patients. Additionally, when assessing the effect of diet on serum potassium, researchers should not only focus on the potassium content of foods, but also consider the type of food and the content of other nutrients. However, more large-scale, multi-center clinical trials are required to provide high-quality evidence support. Besides, further research is also needed to determine the optimal daily potassium intake and beneficial dietary patterns for hemodialysis patients.

Research Progress on the Efficacy and Safety of Spironolactone in Reversing Left Ventricular Hypertrophy in Hemodialysis Patients

The mineralocorticoid receptor antagonist spironolactone has been shown to improve cardiac function and reverse left ventricular hypertrophy in heart failure patients, but there are no consistent findings on the efficacy and safety in hemodialysis patients. Abnormal aldosterone secretion plays a critical role in the formation of left ventricular hypertrophy. Because of the existence of "aldosterone escape", the routine use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers does not completely inhibit aldosterone secretion. Low-dose spironolactone (25 mg/d) has been found in small-sample clinical studies to have a significant positive impact with respect to decreasing left ventricular mass index, increasing left ventricular ejection fraction, reversing left ventricular hypertrophy, and improving cardiovascular function while still being safe. More prospective multicenter clinical trials with large sample sizes are needed, however, to provide convincing evidence.

Does moderate hyperkalemia influence survival in HF? Insights from the MECKI score data base

BACKGROUND

The prognostic role of moderate hyperkalemia in reduced ejection fraction (HFrEF) patients is still controversial. Despite this, it affects the use of renin-angiotensin-aldosterone system inhibitors (RAASi) with therapy down-titration or discontinuation.

OBJECTIVES

Aim of the study was to assess the prognostic impact of moderate hyperkalemia in chronic HFrEF optimally treated patients.

METHODS AND RESULTS

We retrospectively analyzed MECKI (Metabolic Exercise test data combined with Cardiac and Kidney Indexes) database, with median follow-up of 4.2 [IQR 1.9-7.5] years. Data on K⁺ levels were available in 7087 cases. Patients with K⁺ plasma level ≥ 5.6 mEq/L and < 4 mEq/L were excluded. Remaining patients were categorized into normal >4 and < 5 mEq/L (n = 4826, 68%) and moderately high ≥5.0 and ≤ 5.5 mEq/L (n = 496, 7%) K⁺. Then patients were matched by propensity score in 484 couplets of patients. MECKI score value was 7% [IQR 3.1-14.1%] and 7.3% [IQR 3.4-15%] (p = 0.678) in patients with normal and moderately high K⁺ values while cardiovascular mortality events at two years follow-up were 41 (4.2%) and 33 (3.4%) (p = 0.333) in each group respectively.

CONCLUSIONS

Moderate hyperkalemia does not influence patients' outcome in a large cohort of ambulatory HFrEF patients.