Evaluation of Clinical, Echocardiographic, and Therapeutic Characteristics, and Prognostic Outcomes of Coexisting Heart Failure among Patients with Atrial Fibrillation: The Jordan Atrial Fibrillation (JoFib) Study.

BACKGROUND: Atrial fibrillation (AF) is the most commonly encountered cardiac arrhythmia in clinical practice. Heart failure (HF) can occur concurrently with AF. AIM: We compared different demographic, clinical, and echocardiographic characteristics between patients with AF+HF and patients with AF only. Furthermore, we explored whether concurrent HF independently predicts several outcomes (all-cause mortality, cardiovascular mortality, ischemic stroke/systemic embolism (IS/SE), major bleeding, and clinically relevant non-major bleeding (CRNMB)). MATERIALS AND METHODS: Comparisons between the AF+HF and the AF-only group were carried out. Multivariable Cox proportional hazard models were constructed for each outcome to assess whether HF was predictive of any of them while controlling for possible confounding factors. RESULTS: A total of 2020 patients were included in this study: 481 had AF+HF; 1539 had AF only. AF+HF patients were older, more commonly males, and had a higher prevalence of diabetes mellitus, dyslipidemia, coronary artery disease, and chronic kidney disease (p≤0.05). Furthermore, AF+HF patients more commonly had pulmonary hypertension and low ejection fraction (p≤0.001). Finally, HF was independently predictive of all-cause mortality (adjusted HR 2.17, 95% CI (1.66-2.85) and cardiovascular mortality (adjusted HR 2.37, 95% CI (1.68-3.36). CONCLUSION: Coexisting AF+HF was associated with a more labile and higher-risk population among Jordanian patients. Furthermore, coexisting HF independently predicted higher all-cause mortality and cardiovascular mortality. Efforts should be made to efficiently identify such cases early and treat them aggressively.

Metformin as a Potential Adjuvant Antimicrobial Agent Against Multidrug Resistant Bacteria.

INTRODUCTION: The continuous increase in the incidence of bacterial resistance to existing antibiotics represents a worldwide health burden. A surrogate strategy to combat such crisis is to find compounds that restore the antimicrobial activity of the already existing antibiotics against multidrug resistant bacteria. Metformin is a commonly used antidiabetic medication. It has proven benefits in other diseases including cancer, aging-related and infectious diseases. In this study, the potential effect of metformin as an adjuvant therapy to antibiotics was investigated. METHODS: Two multidrug resistant bacterial strains were used; methicillin-resistant Staphylococcus aureus (MRSA; ATCC 33,591) and multidrug resistant Pseudomonas aeruginosa (ATCC BAA-2114). To assess its efficacy, metformin was combined with several antibiotics: levofloxacin, chloramphenicol, rifampicin, ampicillin, and doxycycline. The antibacterial effect of metformin was tested using the micro broth dilution method. The minimum inhibitory concentration (MIC) was also measured. Cytotoxicity studies were also performed on mammalian cells to assess its safety. RESULTS: Metformin exhibited an antibacterial effect when combined with the antibiotics on the two tested strains. It also showed low toxicity on the mammalian cells. Moreover, synergetic studies showed that metformin enhanced the effect of the combined antibiotics, as these combinations provide either a synergistic or additive effect with significant reduction in the MIC. CONCLUSION: Metformin exerts an adjuvant antibacterial effect; thus, it could be a possible candidate as an adjuvant therapy to reduce antimicrobial resistance.

Vitamin D Pretreatment Attenuates Ciprofloxacin-Induced Antibacterial Activity.

BACKGROUND: Ciprofloxacin is an antimicrobial that is commonly used to treat several types of infections. It exerts its antimicrobial activity through interfering with bacterial DNA replication and transcription, leading to increase oxidative stress and eventually bacterial death. Vitamin D, on the other hand, has been found to have DNA protective and antioxidant effects. In the current study, the possible interactive effect of vitamin D on ciprofloxacin-induced cytotoxicity was investigated in various standard bacterial strains. METHODS: The bacterial strains that were used include Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Staphylococcus epidermidis, Acinetobacter baumannii, Proteus mirabilis, and Klebsiella pneumoniae. The antibacterial effect of ciprofloxacin with and without vitamin D treatment of the bacteria was assessed using disc diffusion method and by measuring the minimum inhibitory concentration (MIC) and zones of inhibition of bacterial growth. Moreover, reactive oxygen species (ROS) generation after pretreatment of E. Coli cells with ciprofloxacin and/or vitamin D was measured as a function of as a function of hydrogen peroxide generation. RESULTS: Ciprofloxacin demonstrated a potent antibacterial effect against the tested strains of bacteria. Moreover, pretreatment with vitamin D resulted in protecting the bacteria from the cytotoxicity of ciprofloxacin, this was indicated by the significantly smaller zones of inhibition and higher MIC values compared to ciprofloxacin alone as well as reduced ciprofloxacin-induced ROS generation after treatment with vitamin D. CONCLUSION: Results revealed the possible reduction in the activity of ciprofloxacin when used in combination with vitamin D. This could be explained by the ability of vitamin D to reduce oxidative stress in the bacterial cells.