Alternative medicine in atrial fibrillation treatment-Yoga, acupuncture, biofeedback and more

Identification of Lauric Acid as a Potent Sodium Channel NaV1.5 Blocker from Compound Chinese Medicine Wenxin Keli

Purpose

The major cardiac voltage-gated sodium channel NaV1.5 (INa) is essential for cardiac action potential initiation and subsequent propagation. Compound Chinese medicine Wenxin Keli (WXKL) has been shown to suppress arrhythmias and heart failure. However, its active components have not been fully elucidated. This study focused on identifying the active inhibitor of INa in WXKL and exploring their mode of action in electrophysiological conduction.

Methods

A chemical fraction library was constructed from an aqueous extract of WXKL and screened using an automated patch-clamping system in cells stably expressing the NaV1.5 gene SCN5A. Candidate fractions with INa-inhibition activity were analyzed by HPLC-ESI-IT-TOF-MS and GC-MS to identify the ingredients. NaV1.5 blocker molecules identified by single-cell electrocardiogram were tested in hiPSC-derived cardiomyocytes. We evaluated the SCN5A inhibitory potential of Wenxin Keli effective monomer employing molecular docking and molecular dynamics simulation approaches.

Results

A primary screen of the WXKL chemical library identified five fractions that significantly inhibited the NaV1.5 channel, with one of them rich in poly-saturated fatty acids. Molecular structural characterization revealed the presence of lauric acid, myristic acid, palmitic acid, and stearic acid in the active subfraction. Electrophysiological characterization demonstrated lauric acid (LA) as the most effective monomer for INa-inhibition with an IC50 at 27.40 ± 12.78 μM. LA shifted the steady-state inactivation of INa to more negative potentials and decreased the amplitude of extracellular field potential in hiPSC-derived cardiomyocytes. We demonstrate for the first time that naturally poly-saturated fatty acid, lauric acid, as a potential novel INa blocker. Molecular docking and molecular dynamics simulation suggested that LA binds to the NaV1.5 protein, with a significant binding affinity forming interactions with functionally essential residues and blocks the inward flow of Na+. Mechanistically, lauric acid acts on the fast inactivation of NaV1.5 alter electrophysiology conduction of hiPSC-derived cardiomyocytes and contribute to the antiarrhythmic effect of WXKL.

Conclusion

Lauric acid is a potent blocker for sodium channel NaV1.5 and alleviates arrhythmia via inhibiting INa.

Effectiveness and safety of traditional herbal medicine on cardiac arrhythmic condition: A systematic review and meta-analysis of randomized control clinical trial

INTRODUCTION

The prevalence of cardiac arrhythmia, which can lead to cardiac death, heart failure, and cardioembolic stroke, is increasing. Although various Western medicines for cardiac arrhythmias have been developed, there are still various difficulties in the management of arrhythmias. Traditional herbal medicines (THM) are widely used to manage arrhythmia in East Asia. Therefore, this study aimed to assess the effectiveness and safety of THM in the treatment of arrhythmia.

METHOD

Using a systematic review methodology, we searched for randomized clinical trials on herbal medicines for arrhythmia without complications in 4 databases up to September 2022. The literature search was carried out again, targeting papers published until April 2024.We conducted a risk-of-bias assessment and meta-analysis. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Eighty-two randomized clinical trials were included in this meta-analysis. Total effective rate was significantly better in unspecified arrhythmia (risk ratio [RR]: 1.20, 95% confidence interval [CI]: 1.13-1.26), premature ventricular contraction (RR: 1.29, 95% CI: 1.29-1.33), sinus bradycardia (RR: 1.26, 95% CI: 1.17-1.36), tachycardia (RR: 1.23 95% CI: 1.15-1.32), and atrial fibrillation (RR: 1.17, 95% CI: 1.07-1.27). No severe adverse events were associated with THM. The overall risk of bias was relatively high. The total effective rate was the most frequently assessed clinical outcome variable. Most outcomes were surrogates and not clinical endpoints.

CONCLUSION

THM, alone or in combination with Western medicine, has therapeutic effects on cardiac arrhythmic diseases. However, additional disease-specific clinical outcome variables are required for further studies on THM. Owing to the low quality of the included studies and their small sample sizes, additional large-scale, long-term follow-up, and well-designed randomized controlled clinical trials are required.

SYSTEMATIC REVIEW REGISTRATION NUMBER

Details of the protocol for this systematic review and meta-analysis were registered on the Open Science Framework (OSF. io). (https://osf.io/7r8kn/).

Systematic Evaluation of Efficacy and Safety of Acupuncture Treatment for Patients with Atrial Fibrillation

BACKGROUND:

Atrial fibrillation (AF) is one of the most common types of arrhythmia diagnosed in clinical practice. Due to its negative effects on people’s physical and mental health, it is necessary to prevent and treat AF. Recently, scholars have found that acupuncture can be used to treat AF, but some scholars have questioned its therapeutic efficacy.

AIM:

Therefore, this study was performed to assess the efficacy and safety of acupuncture treatment for AF patients.

METHODS:

Previously published research articles were retrieved from six databases, and the data was analysed using RevMan5.3 software with a statistically significant difference defined as P < 0.05.

RESULTS:

A total of 8 relevant kinds of literature were retrieved containing 633 AF patients (323 in the treatment group and 310 in the control group). Acupuncture treatment increased the total efficacy and the rate of AF cardioversion to sinus rhythm (RR: 1.38; 95% CI: 1.25 to 1.53 vs RR: 1.40;95% CI: 1.16 to 1.69; each P < 0.05), and decreased the time of AF cardioversion to sinus rhythm, the heart rate and incidence of adverse effects (RR: -3.95; 95% CI: -4.98 to -2.91 vs RR: -14.54; 95% CI: -24.09 to -5.00 vs RR: 0.48; 95% CI: 0.21 to 1.11, each P < 0.05). There was difference between retention time more and less than 30 minutes (I2 = 74.9%, P = 0.05). The funnel plot displayed a symmetrical and funnel-form shape, indicating low bias.

CONCLUSION:

Acupuncture has a good therapeutic effect and safety profile on patients with AF, and its application in clinical practice should be considered.

Atrial fibrillation symptom clusters and associated clinical characteristics and outcomes: A cross-sectional secondary data analysis

BACKGROUND

Symptom clusters among adults with atrial fibrillation have previously been identified but no study has examined the relationship between symptom clusters and outcomes.

AIMS

The purpose of this study was to identify atrial fibrillation-specific symptom clusters, characterize individuals with each cluster, and determine whether symptom cluster membership is associated with healthcare utilization.

METHODS

This was a cross-sectional secondary data analysis of 1501 adults from the Vanderbilt Atrial Fibrillation Registry with verified atrial fibrillation. Self-reported symptoms were measured with the University of Toronto Atrial Fibrillation Severity Scale. We used hierarchical cluster analysis (Ward's method) to identify clusters and dendrograms, pseudo F, and pseudo T-squared to determine the ideal number of clusters. Next, we used regression analysis to examine the association between cluster membership and healthcare utilization.

RESULTS

Males predominated (67%) and the average age was 58.4 years. Two symptom clusters were identified, a Weary cluster (3.7%, n=56, fatigue at rest, shortness of breath at rest, chest pain, and dizziness) and an Exertional cluster (32.7%, n=491, shortness of breath with activity and exercise intolerance). Several sociodemographic and clinical characteristics varied by symptom cluster group membership, including age, gender, atrial fibrillation type, body mass index, comorbidity status, and treatment strategy. Women were more likely to experience either cluster ( p<0.001). The Weary cluster was associated with nearly triple the rate of emergency department utilization (incident rate ratio [IRR] 2.8, p<0.001) and twice the rate of hospitalizations (IRR 1.9, p<0.001).

CONCLUSION

We identified two symptom clusters. The Weary cluster was associated with a significantly increased rate of healthcare utilization.

Symptom Clusters in Adults With Chronic Atrial Fibrillation

BACKGROUND

Symptom clusters have not previously been explored among individuals with atrial fibrillation of any type.

OBJECTIVE

The purpose of this study is to determine the number of symptom clusters present among adults with chronic atrial fibrillation and to explore sociodemographic and clinical factors potentially associated with cluster membership.

METHODS

This was a cross-sectional secondary data analysis of 335 Australian community-dwelling adults with chronic (recurrent paroxysmal, persistent, or permanent) atrial fibrillation. We used self-reported symptoms and agglomerative hierarchical cluster analysis to determine the number and content of symptom clusters present.

RESULTS

There were slightly more male (52%) than female participants, with a mean (SD) age of 72 (11.25) years. Three symptom clusters were evident, including a vagal cluster (nausea and diaphoresis), a tired cluster (fatigue/lethargy, weakness, syncope/dizziness, and dyspnea/breathlessness), and a heart cluster (chest pain/discomfort and palpitations/fluttering). We compared patient characteristics among those with all the symptoms in the cluster, those with some of the symptoms in the cluster, and those with none of the symptoms in the cluster. The only statistically significant differences were in age, gender, and the use of antiarrhythmic medications for the heart cluster. Women were more likely to have the heart symptom cluster than men were. Individuals with all of the symptoms in the heart cluster were younger (69.6 vs 73.7 years; P = .029) than those with none of the symptoms in the heart cluster and were more likely to be on antiarrhythmic medications.

CONCLUSION

Three unique atrial fibrillation symptom clusters were identified in this study population.

Berberis vulgaris for cardiovascular disorders: a scoping literature review

Cardiovascular disorders are the leading cause of mortality worldwide. Berberis vulgaris (B. vulgaris) is a commonly used plant in traditional medicine. In recent studies, B. vulgaris showed antiarrhythmic, antihypertensive, anticholinergic, and cardioprotective effects. We reviewed the literature to explore the possible prophylactic and therapeutic roles of B. vulgaris in cardiovascular medicine. A computer literature search was conducted to identify all relevant studies that have investigated the role of B. vulgaris in prevention or treatment of cardiovascular diseases. We also searched the citations of the retrieved articles. Using a systematic approach, we conducted a scoping review that included a total of 37 articles. Twelve studies examined the antihypertensive effects of B. vulgaris, seven studies investigated its antiarrhythmic effects, while its inotropic and cardioprotective effects were evaluated in four and eight studies, respectively. B. vulgaris showed a beneficial effect in reducing blood pressure, enhancing cardiac contractility, and protection from reperfusion injury. However, the mechanisms of these effects are still under investigation. Moreover, it could modify major risk factors for cardiovascular disorders, such as oxidative stress, hyperglycemia, and hyperlipidemia. Further studies are needed to translate these findings into effective cardiovascular medications.

Atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia despite substantial efforts to understand the pathophysiology of the condition and develop improved treatments. Identifying the underlying causative mechanisms of AF in individual patients is difficult and the efficacy of current therapies is suboptimal. Consequently, the incidence of AF is steadily rising and there is a pressing need for novel therapies. Research has revealed that defects in specific molecular pathways underlie AF pathogenesis, resulting in electrical conduction disorders that drive AF. The severity of this so-called electropathology correlates with the stage of AF disease progression and determines the response to AF treatment. Therefore, unravelling the molecular mechanisms underlying electropathology is expected to fuel the development of innovative personalized diagnostic tools and mechanism-based therapies. Moreover, the co-creation of AF studies with patients to implement novel diagnostic tools and therapies is a prerequisite for successful personalized AF management. Currently, various treatment modalities targeting AF-related electropathology, including lifestyle changes, pharmaceutical and nutraceutical therapy, substrate-based ablative therapy, and neuromodulation, are available to maintain sinus rhythm and might offer a novel holistic strategy to treat AF.

Mechanisms underlying atrial-selective block of sodium channels by Wenxin Keli: Experimental and theoretical analysis

INTRODUCTION

Atrial-selective inhibition of cardiac sodium channel current (INa) and INa-dependent parameters has been shown to contribute to the safe and effective management of atrial fibrillation. The present study was designed to examine the basis for the atrial-selective actions of Wenxin Keli.

METHODS

Whole cell INa was recorded at room temperature in canine atrial and ventricular myocytes. Trains of 40 pulses were elicited over a range of pulse durations and interpulse intervals to determine tonic and use-dependent block. A Markovian model for INa that incorporates interaction of Wenxin Keli with different states of the channel was developed to examine the basis for atrial selectivity of the drug.

RESULTS

Our data indicate that Wenxin Keli does not bind significantly to either closed or open states of the sodium channel, but binds very rapidly to the inactivated state of the channel and dissociates rapidly from the closed state. Action potentials recorded from atrial and ventricular preparations in the presence of 5g/L Wenxin Keli were introduced into the computer model in current clamp mode to simulate the effects on maximum upstroke velocity (Vmax). The model predicted much greater inhibition of Vmax in atrial vs. ventricular cells at rapid stimulation rates.

CONCLUSION

Our findings suggest that atrial selectivity of Wenxin Keli to block INa is due to more negative steady-state inactivation, less negative resting membrane potential, and shorter diastolic intervals in atrial vs. ventricular cells at rapid activation rates. These actions of Wenxin Keli account for its relatively safe and effective suppression of atrial fibrillation.