[New clinical opportunities for mineralocorticoid receptor antagonists: focus on antifibrotic effects].

Mineralocorticoid receptor antagonists have been successfully used for many years to treat patients with primary hyperaldosteronism, refractory arterial hypertension and chronic heart failure. The increased interest in this drug in recent years is due to new information about its antifibrotic and antiproliferative effects, both cardiac and extracardiac. The article also discusses the possibility of using spironolactone in patients with the new coronavirus infection SARS-CoV-2 (COVID-19).

Type 2 myocardial infarction and myocardial injury: eligibility for novel medical therapy to derisk clinical trials.

BACKGROUND: Patients with type 2 myocardial infarction (T2MI) and other mechanisms of nonthrombotic myocardial injury have an unmet therapeutic need. Eligibility for novel medical therapy is generally uncertain. METHODS: We predefined colchicine, eplerenone and ticagrelor as candidates for repurposing towards novel therapy for T2MI or myocardial injury. Considering eligibility for randomisation in a clinical trial, each drug was classified according to indications and contraindications for therapy and survival for at least 24 hours following admission. Eligibility criteria for prescription were evaluated against the Summary of Medical Product Characteristics. Consecutive hospital admissions were screened to identify patients with ≥1 high-sensitivity troponin-I value >99th percentile. Endotypes of myocardial injury were adjudicated according to the Fourth Universal Definition of MI. Patients' characteristics and medication were prospectively evaluated. RESULTS: During 1 March to 15 April 2020, 390 patients had a troponin I>URL. Reasons for exclusion: type 1 MI n=115, indeterminate diagnosis n=42, lack of capacity n=14, death <24 hours n=7, duplicates n=2. Therefore, 210 patients with T2MI/myocardial injury and 174 (82.8%) who survived to discharge were adjudicated for treatment eligibility. Patients who fulfilled eligibility criteria initially on admission and then at discharge were colchicine 25/210 (11.9%) and 23/174 (13.2%); eplerenone 57/210 (27.1%) and 45/174 (25.9%); ticagrelor 122/210 (58.1%) and 98/174 (56.3%). Forty-six (21.9%) and 38 (21.8%) patients were potentially eligible for all three drugs on admission and discharge, respectively. CONCLUSION: A reasonably high proportion of patients may be considered eligible for repurposing novel medical therapy in secondary prevention trials of type 2 MI/myocardial injury.

New Horizons: Does Mineralocorticoid Receptor Activation by Cortisol Cause ATP Release and COVID-19 Complications?

This paper attempts to explain how the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus causes the complications that make coronavirus disease 2019 (COVID-19) a serious disease in specific patient subgroups. It suggests that cortisol-associated activation of the mineralocorticoid receptor (MR) in epithelial and endothelial cells infected with the virus stimulates the release of adenosine 5'-triphosphate (ATP), which then acts back on purinergic receptors. In the lung this could produce the nonproductive cough via purinergic P2X3 receptors on vagal afferent nerves. In endothelial cells it could stimulate exocytosis of Weibel-Palade bodies (WPBs) that contain angiopoietin-2, which is important in the pathogenesis of acute respiratory distress syndrome (ARDS) by increasing capillary permeability and von Willebrand factor (VWF), which mediates platelet adhesion to the endothelium and hence clotting. Angiopoietin-2 and VWF levels both are markedly elevated in COVID-19-associated ARDS. This paper offers an explanation for the sex differences in SARS-CoV-2 complications and also for why these are strongly associated with age, race, diabetes, and body mass index. It also explains why individuals with blood group A have a higher risk of severe infection than those with blood group O. Dexamethasone has been shown to be of benefit in coronavirus ARDS patients and has been thought to act as an anti-inflammatory drug. This paper suggests that a major part of its effect may be due to suppression of cortisol secretion. There is an urgent need to trial the combination of dexamethasone and an MR antagonist such as spironolactone to more effectively block the MR and hence the exocytosis of WPBs.