Effects of radiofrequency catheter ablation of atrial fibrillation on soluble P-selectin, von Willebrand factor and IL-6 in the peripheral and cardiac circulation

Unveiling the Role of Endothelial Dysfunction: A Possible Key to Enhancing Catheter Ablation Success in Atrial Fibrillation

Atrial fibrillation, a prevalent type of arrhythmia, is increasingly contributing to the economic burden on healthcare systems. The development of innovative treatments, notably catheter ablation, has demonstrated both impressive and promising outcomes. However, these treatments have not yet fully replaced pharmaceutical approaches, primarily due to the relatively high incidence of atrial fibrillation recurrence post-procedure. Recent insights into endothelial dysfunction have shed light on its role in both the onset and progression of atrial fibrillation. This emerging understanding suggests that endothelial function might significantly influence the effectiveness of catheter ablation. Consequently, a deeper exploration into endothelial dynamics could potentially elevate the status of catheter ablation, positioning it as a primary treatment option for atrial fibrillation.

Endovascular Interventional Procedure is a Significant Risk Factor of Postsurgical Gout: A Retrospective Cohort Study

INTRODUCTION

Surgery is a risk factor for flares in people with gout. However, gout flares after endovascular interventional procedures are not well understood. The aim of this study was to evaluate the clinical features and risk factors for gout flare that develop during the postsurgical period including endovascular procedures.

METHODS

We enrolled 222 patients with gout who developed postsurgical gout and 196 controls who had histories of gout but did not develop gout flares after surgery within 20 days. Clinical characteristics of patients who developed a postsurgical gout flare were compared with the controls.

RESULTS

The rate of endovascular interventional procedures was higher (38.74% vs. 13.48%, P < 0.001) in the flare group than in the no-flare group and lower in orthopedic surgery (13.96% vs. 41.84%, P < 0.001). The Cox model showed that endovascular interventional procedures (HR, hazard ratio 1.752; 95% CI, confidence interval 1.126-2.724, P = 0.013) and presurgical uric acid levels of ≥ 7 mg/dl (HR 1.489; 95% CI 1.081-2.051, P = 0.015) were significantly associated with increased risks of postsurgical gout flare, and taking colchicine before surgery were significantly associated with decreased risk of postsurgical gout flare (HR 0.264; 95% CI 0.090-0.774, P = 0.015). There was no significant difference in the types of endovascular interventional procedures between the flare group and the no-flare group.

CONCLUSIONS

Patients with a history of gout should be more alert to recurrence gout flares after endovascular interventional procedures. Adequate presurgical control of serum uric acid levels and/or prophylactic treatment with colchicine will help prevent gout flares during the postsurgical period.

The Association between Coagulation and Atrial Fibrillation

The existing literature highlights the presence of numerous coagulation factors and markers. Elevated levels of coagulation factors are associated with both existing and newly diagnosed cases of atrial fibrillation (AF). However, this article summarizes the role of coagulation in the pathogenesis of AF, which includes fibrinogen and fibrin, prothrombin, thrombomodulin, soluble urokinase plasminogen activator receptor, von Willebrand factor, P-selectin, D-dimer, plasminogen activator inhibitor-1, and platelet activation. Coagulation irregularities play a significant role in the pathogenesis of AF.

It can be safe to discontinue oral anticoagulants after successful atrial fibrillation ablation: A systematic review and meta-analysis of cohort studies

BACKGROUND

Current guidelines recommended that oral anticoagulants (OACs) should last for a minimum first 2 months after atrial fibrillation (AF) ablation and the long-term decision of anticoagulation after AF ablation should be based on the individual patient's risk of stroke rather than the rhythm status. There is controversy about the safety of discontinuing OACs in patients with atrial fibrillation after the blanking period due to the divergences between consensus recommendations and clinical practice.

METHODS

Electronic bibliographic sources (PubMed, Embase, and Web of Science) were searched until August 2023 to identify cohort studies about the safety of discontinuing OACs in patients with AF after the blanking period. The primary outcome was thromboembolism (TE). The secondary outcome was major bleeding events (MBEs). Two authors extracted articles independently using predefined data fields. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated based on a random-effects model.

RESULTS

A total of 16 studies (11 prospective cohorts and 5 retrospective cohorts) enrolling 23,942 patients (14,382 OFF-OAC and 9560 ON-OAC) were included in our analysis. No significant difference emerged in the risk of TE between OFF-OAC and ON-OAC patients following AF ablation after the banking period (OR = 0.66; 95%CI, 0.43-1.01). Similar results emerged in the patients with a high risk of TE after stratification by the risk level of TE (OR = 0.72; 95%CI, 0.25-2.08). A significant reduction in incidences of major bleeding was found in the OFF-OAC patients compared with the ON-OAC patients (OR = 0.23; 95%CI, 0.12-0.42). Subgroup analyses for TE found a reduction of incidences in the subgroups who switched to antiplatelet drugs and with a follow-up duration <3 years. Subgroup analyses for MBEs found a significant reduction of incidences in all subgroups.

CONCLUSIONS

Our study suggests it can be safe to discontinue OACs after successful AF ablation. Discontinuation of OACs may reduce the risk of MBEs while not increasing the risk of TE.

Radiofrequency ablation reduces expression of SELF by upregulating the expression of microRNA-26a/b in the treatment of atrial fibrillation

BACKGROUND

In this study, we aimed to investigate the role of miR-26a and miR-26b in the management of AF.

METHODS

Real-time PCR was carried out to determine plasma microRNA expression in AF patients pre- and post-radiofrequency ablation. The correlation between the expression of SELP and miR-26a/miR-26b was also studied using luciferase assays to establish a miR-26a/miR-26b/SELP signaling pathway.

RESULTS

The relative expression of SELP reached its peak in pre-ablation AF ( +) patients, while ablation treatment reduced the expression of SELP in AF ( +) patients. Similarly, AF pigs showed dysregulation of miR-26a/b and SELP, thus verifying the involvement of miR-26a/b and SELP in AF. Meanwhile, the regulatory association between SELP and miR-26a/b was also investigated, and the results showed that the presence of pre-miR-26a/b increased the levels of miR-26a/b and inhibited the mRNA/protein expression of SELP. Finally, using bioinformatic tools and luciferase assays, SELP mRNA was confirmed as the target of miR-26a/b, which affected the effect of AF ablation treatment.

CONCLUSIONS

RFA helped to restore circulating levels of miR-26, which were reduced in atrial fibrillation. Meanwhile, miR-26 is a potential cause for the elevated plasma levels of pro-thrombogenic SELP in that disease.

Long-Term Stroke Risk in Patients Undergoing Left Atrial Appendage Ablation With and Without Complete Isolation

Background: Catheter ablation (CA) for atrial fibrillation (AF), may require ablation beyond the pulmonary veins. Prior data suggest that additional LA ablation, particularly left atrial appendage (LAA) ablation, may alter atrial function leading to increased risk of ischemic stroke or transient ischemic attack (IS/TIA). We sought to study the long-term risk of IS/TIA in patients receiving ablation at the LAA compared to those receiving PVI alone and those receiving PVI with additional non-LAA locations.

Methods: 350 patients who underwent CA for AF from 2008 to 2018 were included in the study. Locations of ablation in LA evaluated were the posterior wall, anterior wall, inferior wall, inter-atrial septum, lateral wall and the left atrial appendage (LAA). Patients undergoing LAA ablation were further divided as complete isolation (LAAi) and without complete isolation (LAAa).

Results: Mean follow up of 4.8 years. In entire cohort, risk of IS/TIA was 1.62/100 patient-years (pys). The risk was highest in patients with LAAi (3.81/100 pys), followed by ablation LAAa (3.74/100 pys). Amongst all LA locations, only LAAi (HR 3.32, p = 0.03) and LAAa (HR 3.18, p = 0.02) were statistically significant predictors of IS/TIA after adjusting for OAC (Oral anticoagulant) use and baseline CHA₂DS₂VASc score.

Conclusions: During long term follow-up, only ablation at the left atrial appendage with and without complete isolation was independently associated with an increased risk of IS/TIA in patients undergoing CA for AF. Potential strategies to reduce stroke risk, such as LAA closure, should be considered in these patients.

Intracardiac Fibrinolysis and Endothelium Activation Related to Atrial Fibrillation Ablation with Different Techniques

Objective

The effect of pulmonary vein isolation (PVI) on fibrinolytic and endothelial activation with currently applied periprocedural anticoagulation has not been explored. We measured markers of fibrinolysis and endothelium activation before and after PVI with the second-generation cryoballoon (Cryo), pulmonary vein ablation catheter (PVAC-Gold), and irrigated radiofrequency (IRF).

Methods

Markers of fibrinolysis and endothelium activation in left atrial (LA) blood samples were measured in 31 patients before and after PVI (Cryo:10, PVAC-Gold: 7, IRF: 14). Periprocedural anticoagulation included uninterrupted vitamin K antagonist and iv heparin (ACT≥300 sec) during LA dwelling.

Results

Levels of D-dimer (median; interquartile range, mgFEU/L) increased with all techniques (PVAC: 0.34; 0.24–0.50 versus 0.70; 0.61–1.31; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAP complex level (ng/ml) increased after Cryo (247.3, 199.9–331.6 versus 270.9, 227.9–346.7; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAI-1 activity (%) decreased with the PVAC (1.931; 0.508–3.859 versus 0.735, 0.240–2.707; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; VWF antigen levels and FVIII activity increased after PVI with all the 3 techniques. The levels of soluble VCAM-1 (ng/ml) did not change after PVAC procedures, but increased after Cryo (542, 6; 428.5–753.1 versus 619.2; 499.8–799.0; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93;

Conclusion

PVI with contemporary ablation techniques and periprocedural antithrombotic treatment induces coagulation and endothelium activation of similar magnitude with different ablation methods.

[Biomarkers and atrial fibrillation : Prediction of recurrences and thromboembolic events after rhythm control management]

Atrial fibrillation (AF) is the most common arrhythmia in clinical praxis and is associated with an increased risk for cardio- and cerebrovascular complications leading to an increased mortality. Catheter ablation represents one of the most important and efficient therapy strategies in AF patients. Nevertheless, the high incidence of arrhythmia recurrences after catheter ablation leads to repeated procedures and higher treatment costs. Recently, several scores had been developed to predict rhythm outcomes after catheter ablation. Biomarker research is also of enormous interest. There are many clinical and blood biomarkers pathophysiologically associated with AF occurrence, progression and recurrences. These biomarkers-including different markers in blood (e. g. von Willebrand factor, D‑dimer, natriuretic peptides) or urine (proteins, epidermal grown factor receptor) but also cardiac imaging (echocardiography, computed tomography, magnetic resonance imaging)-could help to improve clinical scores and be useful for individualized AF management and optimized patients' selection for different AF treatment strategies. In this review, the role of diverse biomarkers and their predictive value related to AF-associated complications are discussed.

Intracardiac Hemostasis and Fibrinolysis Parameters in Patients with Atrial Fibrillation

AIMS

To identify intracardiac hemostasis or fibrinolysis abnormalities, which are associated with atrial fibrillation (AF) and increase the risk of thromboembolism.

PATIENTS AND METHODS

Patient group consisted of 24 patients with AF and control group included 14 individuals with other supraventricular tachycardia undergoing transcatheter radiofrequency ablation. Blood samples were drawn from the femoral vein (FV), left atrium (LA), and left atrial appendage (LAA) before the ablation procedure. Fibrinogen, factor VIII (FVIII) and factor XIII activity, von Willebrand factor (VWF) antigen, thrombin-antithrombin (TAT) complex, quantitative fibrin monomer (FM), plasminogen, α₂-plasmin inhibitor, plasmin-α₂-antiplasmin (PAP) complex, PAI-1 activity, and D-dimer were measured from all samples.

RESULTS

Levels of FVIII and VWF were significantly elevated in the FV and LA of AF patients as compared to controls. TAT complex, FM, PAP complex, and D-dimer levels were significantly elevated in the LA as compared to FV samples in case of both groups, indicating a temporary thrombotic risk associated with the catheterization procedure.

CONCLUSIONS

None of the investigated hemostasis or fibrinolysis parameters showed significant intracardiac alterations in AF patients as compared to non-AF controls. AF patients have elevated FVIII and VWF levels, most likely due to endothelial damage, presenting at both intracardiac and systemic level.

Thromboembolic and bleeding risks in patients undergoing atrial fibrillation ablation: oral anticoagulation perspectives

INTRODUCTION

Atrial fibrillation (AF) is a cause of significant morbidity and mortality. Catheter ablation for AF (CAAF) has emerged as an effective treatment option of rhythm control for patients with symptomatic AF. However, the risk of thromboembolism and bleeding in the periprocedural period represent a worrisome complication of this therapy. The reported incidence of thromboembolic and bleeding events associated with CAAF varies from 0.9% to 5% depending on the CAAF strategy and the anticoagulation regimen used in the periprocedural period. Areas covered: The different anticoagulation regimens used prior to, during, and after CAAF to minimize the risk of thromboembolic and bleeding events are reviewed. The use of uninterrupted oral anticoagulation and appropriate heparin dosing to achieve safe activated clotting time levels are also detailed. A comprehensive approach with assessment of individual risk for thromboembolic and bleeding complications, and understanding the pharmacokinetics of the anticoagulant agents available is also reviewed. Expert opinion: The key advances done in the periprocedural anticoagulation field include the use of uninterrupted anticoagulation strategies in patients undergoing AF ablation and efforts to simplify the selection of patients who need LAA thrombus screening prior to ablation.

Periprocedural Management of Novel Oral Anticoagulants During Atrial Fibrillation Ablation: Controversies and Review of the Current Evidence

Oral anticoagulation (OAC) has been the cornerstone for the prevention of thromboembolic complications in patients with atrial fibrillation (AF) at significant risk of stroke. Catheter ablation is an established efficacious technique for the treatment of AF. Ameliorating the risk of stroke or transient ischaemic attack (TIA) in patients with AF undergoing ablation requires meticulous planning of pharmacotherapy. The advent of non-vitamin K oral anticoagulants (NOACs) has broadened the therapeutic scope, representing a viable alternative to traditional vitamin K antagonists (VKA) in non-valvular AF. Potential advantages of NOACs include greater pharmacokinetic predictability, at least comparable efficacy as compared to VKA and a superior haemorrhagic complication profile. However, robust evidence for the safety and efficacy of periprocedural NOAC use for AF ablation remains uncertain with a non-uniform clinical approach between and within institutions. The following review will summarise the current and emerging evidence on periprocedural management of NOACs in patients undergoing catheter ablation of AF. An overview of NOAC pharmacology will provide a foundation for the review of reversal agents in the context of catheter ablation of AF. The purpose of the review is to outline key studies and identify key areas for further critical research with the ultimate aim of developing evidence-based guidelines for optimal care.

Berberine protects vascular endothelial cells in hypertensive rats

OBJECTIVE

This study is to investigate the effect and mechanism of berberine on vascular endothelial cell injury.

METHODS

The isolated aortic endothelial cells were divided into negative control group, spontaneous hypertension group, and berberine group (1.25, 2.5, and 5 μmol/L berberine). CCK-8 assay was performed to detect cell proliferation. Annexin V-FITC flow cytometry and Hochest33342/PI staining were used to measure cell apoptosis. Expression of TLR4, Myd88, and NF-κB was detected with Western blotting analysis. Level of IL-6 and TNF-α was measured with ELISA.

RESULTS

Compared with spontaneous hypertension group, cell proliferation in berberine group was significantly improved (P < 0.05). Flow cytometry showed that cell apoptosis was reduced in berberine group in a dose-dependent manner and there was statistically significant difference between spontaneous hypertension group and berberine group (P < 0.05). This result was further confirmed by Hochest33342/PI staining. Expression levels of TLR4, Myd88 and NF-κB were increased in spontaneous hypertension group. However, their expression levels were significantly reduced in berberine group than those in spontaneous hypertension group (P < 0.05). Similarly, levels of IL-6 and TNF-α were increased in spontaneous hypertension group and decreased in berberine group. And, the difference was significant (P < 0.05). Importantly, there were significant differences between negative control group and spontaneous hypertension group in cell proliferation, apoptosis, and expression of TLR4, Myd88, NF-κB, IL-6 and TNF-α.

CONCLUSION

Berberine plays a protective role in vascular endothelial cell injury through inhibiting apoptosis and expression of TLR4, Myd88, NF-κB, IL-6 and TNF-α.

Is dabigatran efficacy enough to prevent stroke in atrial fibrillation patient with high CHADS2 score during peri-procedural catheter radiofrequency ablation? A case report with literature review

Atrial fibrillation (AF) is a major cause of thromboembolic (TE) events including stroke and transient ischemic attacks, catheter radiofrequency ablation (CA) has been demonstrated to effectively eliminate AF in majority of patients. During the peri-procedural CA of AF, dabigatran, a reversible direct thrombin inhibitor, has been proved as safe and efficacy as warfarin in the prevention of thromboembolic complication. However, for patients with CHADS2 score ≥3, sometimes dabigatran may not be an ideal substitute of warfarin. The current study presents delayed stroke occurred in a middle-aged AF patient with high CHADS2 score who had undergone successful CA of AF being on dabigatran, trans esophageal echocardiogram (TEE) detected a clot in the left atrium appendage (LAA) and magnetic resonance image (MRI) indicated stroke of left basal ganglia, therefore anticoagulant was switched to warfarin with well controlled international normalization ratio (INR) ranging from 2.0-3.0 and the patient eventually recovered without any TE events during the subsequent follow-up.