Impact of internal and external electrical cardioversion on cardiac specific enzymes and inflammation in patients with atrial fibrillation and heart failure

HGF ameliorates cardiomyocyte apoptosis and inflammatory response in septic patients via the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway

OBJECTIVE

This study aimed to analyze the impact of HGF on cardiomyocyte injury, apoptosis, and inflammatory response induced by lipopolysaccharide (LPS).

METHODS

Enzyme-linked immunosorbent assay (ELISA) was utilized to quantify the levels of HGF, interleukin (IL)-6, IL-10, creatine phosphokinase-isoenzyme-MB (CK-MB), and cardiac troponin I (cTnI) in the samples. qPCR and Western blotting (WB) were employed to assess the mRNA and protein expressions of HGF, IL-10, IL-6, PI3K, AKT, p-PI3K, and p-AKT.

RESULTS

The outcomes of the in vivo experiment revealed that serum levels of IL-6, IL-10, HGF and SOFA scores in the SC group were elevated in contrast to the non-SC group. The correlation analysis indicated a substantial and positive association among serum HGF, IL-6, and IL-10 levels and SOFA scores. Relative to IL-6, IL-10 levels, and SOFA scores, serum HGF demonstrated the highest diagnostic value for SC. Following LPS administration to stimulate H9c2 cells across various periods (0, 12, 24, 48, and 72 h), the levels of myocardial injury markers (CK-MB and cTnI) in the cell supernatants, intracellular inflammatory factors (mRNA and protein levels of IL-10 and IL-6), apoptosis and ROS levels, exhibited a gradual increase followed by a subsequent decline. Following the overexpression of HGF, there was an increase in cell viability, and a decrease in apoptosis, inflammation, oxidative stress injuries, and the protein phosphorylation expressions of PI3K and AKT.. After knockdown of HGF expression, the activity of LPS-induced H9c2 cells was further reduced, leading to increased cell injury, apoptosis, inflammation, oxidative stress,and the expression levels of PI3K and Akt protein phosphorylation were further elevated.

CONCLUSION

HGF was associated with decreased LPS-induced H9c2 apoptosis and inflammation in H9c2 cells, alongside an improvement in cell viability, indicating potential cytoprotective effects. The mechanism underlying these impacts may be ascribed to the suppression of the PI3K/AKT signaling pathway.

Current Drug Treatment Strategies for Atrial Fibrillation and TASK-1 Inhibition as an Emerging Novel Therapy Option

Atrial fibrillation (AF) is the most common sustained arrhythmia with a prevalence of up to 4% and an upwards trend due to demographic changes. It is associated with an increase in mortality and stroke incidences. While stroke risk can be significantly reduced through anticoagulant therapy, adequate treatment of other AF related symptoms remains an unmet medical need in many cases. Two main treatment strategies are available: rate control that modulates ventricular heart rate and prevents tachymyopathy as well as rhythm control that aims to restore and sustain sinus rhythm. Rate control can be achieved through drugs or ablation of the atrioventricular node, rendering the patient pacemaker-dependent. For rhythm control electrical cardioversion and pharmacological cardioversion can be used. While electrical cardioversion requires fasting and sedation of the patient, antiarrhythmic drugs have other limitations. Most antiarrhythmic drugs carry a risk for pro-arrhythmic effects and are contraindicated in patients with structural heart diseases. Furthermore, catheter ablation of pulmonary veins can be performed with its risk of intraprocedural complications and varying success. In recent years TASK-1 has been introduced as a new target for AF therapy. Upregulation of TASK-1 in AF patients contributes to prolongation of the action potential duration. In a porcine model of AF, TASK-1 inhibition by gene therapy or pharmacological compounds induced cardioversion to sinus rhythm. The DOxapram Conversion TO Sinus rhythm (DOCTOS)-Trial will reveal whether doxapram, a potent TASK-1 inhibitor, can be used for acute cardioversion of persistent and paroxysmal AF in patients, potentially leading to a new treatment option for AF.

Clinical impact of serial change in brain natriuretic peptide before and after catheter ablation in patients with atrial fibrillation and heart failure

BACKGROUND

Brain natriuretic peptide (BNP) predicts the prognosis in patients with atrial fibrillation (AF) and heart failure (HF); however, the level of BNP can change immediately after restoration of sinus rhythm. We aimed to investigate the clinical impact of serial change in BNP level before and after catheter ablation for AF, on the prognosis.

METHODS

In this retrospective single center study, 162 consecutive patients (67±9 years, 66.7% male) with AF and concomitant HF who underwent catheter ablation were examined. We analyzed the cardiac rhythm and % change in BNP pre- and post-ablation.

RESULTS

BNP increased by 32.7% (-4.5% to 51.3%) in patients with sinus rhythm at baseline (sinus rhythm group: N=50) and decreased by 47.6% (20.9 to 61.6%) in patients with AF rhythm at baseline. Patients with AF rhythm at baseline were categorized into two groups according to the median value of reduction in % BNP; patients with good % BNP reduction (good BNP-R group; N=56), and with poor % BNP reduction (poor BNP-R group; N=56). Although the rate of recurrence of AF after ablation was comparable between the good and poor BNP-R groups, poor BNP-R was an independent predictor of subsequent composite events including HF hospitalization, ischemic stroke, and all cause of death after ablation, even after adjusting for other confounders (hazard ratio: 6.85, 95% confidence interval: 2.16 to 21.7, p-value=0.001). In the longitudinal analysis of echocardiographic parameters, shortening of the left ventricular end-diastolic diameter with preserved ejection fraction was evident except in the poor BNP-R group.

CONCLUSION

In patients with AF and HF, poor % BNP reduction was an independent predictor of adverse outcome, although the rate of recurrence of AF was comparable. Serial BNP measurement might help in better identification of high-risk patients in whom sinus rhythm is restored with catheter ablation.