Optimal diuretic strategies in heart failure

Phenolic profile, in vitro antimicrobial and in vivo diuretic effects of endemic wild thyme Thymus comosus Heuff ex. Griseb. (Lamiaceae) from Romania

Thymus comosus Heuff ex. Griseb. (Lamiaceae) is a wild thyme species endemic for Romanian Carpathian areas, frequently collected as substitute for collective herbal product Serpylli herba, cited as antibacterial and diuretic remedy in traditional medicine. The present study aimed to evaluate the in vivo diuretic effect and in vitro antimicrobial properties of three herbal preparations (infusion-TCI, tincture-TCT and an hydroethanolic extract prepared through an optimized ultrasound-assisted method-OpTC) obtained from the aerial parts of T. comosus Heuff ex. Griseb, also evaluating their comprehensive phenolic profile. In vivo diuretic effect was tested using Wistar rats treated orally with each herbal preparation (125 and 250 mg/kg dispersed in 25 ml/kg isotonic saline solution) and quantified based on cumulative urine output (ml), diuretic action and diuretic activity. Additionally, sodium and potassium excretion were monitored using a potentiometric method with selective electrodes. In vitro antibacterial and antifungal activities were assessed using p-iodonitrotetrazolium chloride assay against six bacterial strains and six fungal strains by monitoring minimum inhibitory concentration (MICs), minimum bactericidal concentrations (MBCs) and minimum fungicidal concentrations (MFCs). Finally, phenolic profile of the aforementioned herbal extracts was evaluated using an ultra-high-pressure liquid chromatography (UHPLC) coupled with high-resolution mass spectrometry (HRMS) method to check the impact of the different preparations on the most abundant and significant compounds. All the extracts exerted a mild diuretic action, TCT and OpTC inducing the most intense diuretic effect. Both herbal preparations produced a statistically significant, dose-dependent and gradual increase of the urine output, the effect being more intense at 24 h (6.63-7.13 ml/24 h). Potentiometric evaluation of urine samples collected from treated rats revealed a clear and mild natriuretic and kaliuretic effect after the administration. In terms of antimicrobial activity, E. coli (MIC-0.38 mg/ml), B. cereus (MIC-0.75 mg/ml)), Penicillium funiculosum and P. verrucosum var. cyclopium (MIC-0.19 mg/ml) showed the greater sensitivity to the tested extracts, respectively. UHPLC-HRMS screening showed that the bioactive potential of T. comosus herbal preparations was likely related to the higher amounts of phenolic acids (including rosmarinic acid), flavonoids (mainly flavones and derivatives) and other phenolics (such as different isomers of salvianolic acids) in their composition. The obtained results support the ethnopharmacological evidence regarding the mild diuretic and antibacterial potentials of the endemic wild thyme T. comosus, this study being the first one that assessed the aforementioned bioactivities for this species.

Diuretic Resistance Prediction and Risk Factor Analysis of Patients with Heart Failure During Hospitalization

Objectives

This study performed a prediction and risk factor analysis of diuretic resistance (DR) in patients with decompensated heart failure during hospitalization.

Methods

The data of patients with decompensated heart failure treated in 2010-2018 with DR (n = 3,383) or without DR (n = 15,444) were retrospectively collected from Chinese PLA General Hospital medical records. Statistical analysis of baseline was performed on two groups of people, and the risk factor of DR was analyzed through logic regression. Six machine learning models were built accordingly, and the adjustment of model super parameters was performed by using Bayesian optimization method. Finally, the optimal algorithm was selected according to prediction efficiency.

Results

The preliminary analysis of variance showed significant differences in the incidence of DR among patients with lung infection, hyperlipidemia, type 2 diabetes, and kidney disease. There were significant differences in estimated glomerular filtration rate (eGFR) (P < 0.001). In addition, some physical indicators like BMI were different, the laboratory results like mean red blood cell volume or C-reactive protein assay were also significantly different. The optimal classification model indicated that the best cutoff points for risk factors were vein carbon dioxide, 21 mmol/L and 29 mmol/L; total protein, 64 g/L; pro-brain natriuretic peptide (pro-BNP), 7,600 pg/mL; eGFR, 50 mL/(min ∙ 1.73 m2); serum albumin, 33 g/L; hematocrit, 0.32% and 0.56%; red blood cell volume distribution width, 13; and age, 59 years. The optimal area under the curve was 0.9512. The ranked features derived from the model were age, abnormal sodium level, pro-BNP level, serum albumin level, D-dimer level, direct bilirubin level, and eGFR.

Conclusions

The DR risk prediction model based on a gradient boosting decision tree created here identified its important risk factors. The model made very accurate predictions using simple indicators and simultaneously calculated cutoff values to help doctors predict the occurrence of DR.

Development of vericiguat: The first soluble guanylate cyclase (sGC) stimulator launched for heart failure with reduced ejection fraction (HFrEF)

In recent years, with improvements in treatments for heart failure (HF), the survival period of patients has been extended. However, the emergence of some patients with repeated hospitalizations due to their worsening conditions and low survival rates followed. Currently, few drugs are available for such patients. Vericiguat was first drug approved for the treatment of symptomatic patients with chronic HF with reduced ejection fraction (HFrEF) to reduce the occurrence of worsening HF. This article provides comprehensive information about vericiguat in terms of drug design and development, structure-activity relationship (SAR), synthesis, pharmacological efficacy, and clinical practice. In addition, insights into the current vericiguat trials and treatments of HF are also discussed.

Management of Obstructive Sleep Apnea in Patients With Heart Failure

Sleep apnea is traditionally classified as obstructive sleep apnea (OSA), which occurs when the upper airway collapses due to the relaxation of oropharyngeal musculature, and central sleep apnea occurs when the brainstem cannot stimulate breathing. Most sleep apnea in patients with heart failure (HF) results from coexisting OSA and central sleep apnea (CSA), or complex sleep apnea syndrome. OSA and CSA are common in HF and can be involved in its progression by exposure to the heart to intermittent hypoxia, increased preload and afterload, activating sympathetic, and decreased vascular endothelial function. A majority of treatments have been investigated in patients with CSA and HF; however, less or short-term randomized trials demonstrated whether treating OSA in patients with HF could improve morbidity and mortality. OSA could directly influence the patient's recovery. This review will focus on past and present studies on the various therapies for OSA in patients with HF and summarize CSA treatment options for reasons of reference and completeness. More specifically, the treatment covered include surgical and non-surgical treatments and reported the positive and negative consequences for these treatment options, highlighting possible implications for clinical practice and future research directions.