Effect of electroacupuncture on porcine cardiac excitability induced by left stellate ganglion stimulation

A Comprehensive Analysis of Conventional Acupuncture and Pharmacological Approaches for Cardiac Arrhythmias: An Umbrella Review

With a global incidence of approximately 3.4% and an annual mortality rate of 3.7 million, cardiac arrhythmias (CAs) are a pressing global health issue. Their increasing prevalence, especially among older people, is intensifying the challenge for health care systems worldwide. This study aims to compare the safety and effectiveness of acupuncture and pharmacological treatments for CAs, addressing critical gaps in understanding optimal therapeutic approaches. A search of PubMed, EMBASE, and the Cochrane database of systematic reviews was performed to identify data compiled through September 2023 for this umbrella review. Randomized controlled trials (RCTs) as the foundation for meta-analyses and peer-reviewed systematic reviews were the primary focus of the literature search. The Grading of Recommendations Assessment, Development, and Evaluation method was used to assess the overall certainty of the evidence, whereas AMSTAR 2 and the Cochrane Collaboration tool were used to evaluate the quality of the included reviews. Following a comprehensive review, three systematic analyses of 27 RCTs were integrated. Acupuncture led to a slightly greater reduction in the recurrence rate of paroxysmal supraventricular tachycardia (SVT) compared to standard pharmaceutical therapy (risk ratio [RR], 1.06; 95% confidence interval [CI], 0.88-1.27; I2 = 56%; P = .55), although the difference was not statistically significant. In contrast, acupuncture significantly outperformed pharmacological treatment in the context of ventricular premature beats (VPBs) (RR, 1.16; 95 CI, 1.08-1.25; I2 = 0%; P < .0001). The reduction in paroxysmal atrial fibrillation (AF)/atrial flutter was increased with acupuncture, albeit without statistical significance (RR, 1.12; 95% CI, 0.88-1.42; I2 = 0%; P = .36). Acupuncture also led to a greater reduction in heart rate (HR) compared to pharmaceutical treatment despite notable heterogeneity and a lack of statistical significance (mean difference, -1.55; 95% CI, -41.37 to 38.28; I2 = 99%; P = .94). Adverse events were effectively managed, affirming the favorable safety profile of acupuncture. Our study suggests that acupuncture leads to a greater reduction in the recurrence rates of VPBs, AF, and atrial flutter but not significantly so in paroxysmal SVT or post-treatment HR. While promising for specific arrhythmias, the varying effectiveness of acupuncture underscores the need for further research and clinical assessment to determine its precise role and suitability in managing particular cardiac conditions.

Modulating activity of PVN neurons prevents atrial fibrillation induced circulation dysfunction by electroacupuncture at BL15

BACKGROUND

Circulation dysfunction is a major contributing factor to thrombosis in patients with atrial fibrillation (AF) for which effective interventions are lacking. Growing evidence indicates that regulating the paraventricular nucleus (PVN), an autonomic control center, could offer a novel strategy for treating cardiovascular and circulatory diseases. Concurrently, electroacupuncture (EA) at Xinshu (BL15), a form of peripheral nerve stimulation, has shown efficacy in treating several cardiovascular conditions, although its specific mechanism remains unclear. This study aimed to assess the impact of EA at BL15 on circulatory dysfunction in a rat AF model and investigate the pivotal role of PVN neuronal activity.

METHODS

To mimic the onset of AF, male SD rats received tail intravenous injection of ACh-CaCl2 and were then subjected to EA at BL15, sham EA, or EA at Shenshu (BL23). Macro- and micro-circulation function were evaluated using in vivo ultrasound imaging and laser doppler testing, respectively. Vasomotricity was assessed by measuring dimension changes during vascular relaxation and contraction. Vascular endothelial function was measured using myograph, and the activation of the autonomic nerve system was evaluated through nerve activity signals. Additionally, chemogenetic manipulation was used to block PVN neuronal activation to further elucidate the role of PVN activation in the prevention of AF-induced blood circulation dysfunction through EA treatment.

RESULTS

Our data demonstrate that EA at BL15, but not BL23 or sham EA, effectively prevented AF-induced macro- and micro-circulation dysfunction. Furthermore, EA at BL15 restored AF-induced vasomotricity impairment. Additionally, EA treatment prevented abnormal activation of the autonomic nerve system induced by AF, although it did not address vascular endothelial dysfunction. Importantly, excessive activation of PVN neurons negated the protective effects of EA treatment on AF-induced circulation dysfunction in rats.

CONCLUSION

These results indicate that EA treatment at BL15 modulates PVN neuronal activity and provides protection against AF-induced circulatory dysfunction.

Restoring the Autonomic Balance in an Atrial Fibrillation Rat Model by Electroacupuncture at the Neiguan Point

OBJECTIVES

Autonomic nervous activity imbalance plays an important role in atrial fibrillation (AF). AF can be treated by acupuncture at the Neiguan point (PC6), but the mechanism remains elusive. Here, we investigated autonomic nervous system activity in electroacupuncture (EA) at PC6 in a rat AF model.

MATERIAL AND METHODS

In this study, we established a rat AF model via tail vein injection with ACh-CaCl2 for ten consecutive days with or without EA at PC6. AF inducibility and heart rate variability (HRV) were assessed by electrocardiogram. Next, we completed in vivo recording of the activity of cervical sympathetic and vagal nerves, respectively. Finally, the activities of brain regions related to autonomic nerve regulation were assessed by c-Fos immunofluorescence and multichannel recording.

RESULTS

EA at PC6 decreased AF inducibility and prevented changes in HRV caused by ACh-CaCl2 injection. Meanwhile, EA at PC6 reversed the increased sympathetic and decreased vagal nerve activity in AF rats. Furthermore, EA treatment downregulated increased c-Fos expression in brain regions, including paraventricular nucleus, rostral ventrolateral medulla, and dorsal motor nucleus of the vagus in AF, while c-Fos expression in nucleus ambiguus was upregulated with EA.

CONCLUSION

The protective effect of EA at PC6 on AF is associated with balance between sympathetic and vagal nerve activities.

Acupuncture as an adjunctive therapy for arrhythmia: a Delphi expert consensus survey

Background

Current evidence suggests that acupuncture is an effective adjunctive therapy that can bring potential benefits to patients with cardiac arrhythmias. However, there are relevant gaps in the optimal therapeutic strategy, which may cause uncertainties on the best practice of acupuncture treatment for arrhythmia. We aim to develop consensus-based recommendations for clinical guidance on acupuncture treatment of cardiac arrhythmias.

Methods

A multidisciplinary panel of specialists was invited to participate in a two-round semi-open clinical issue investigation. Meanwhile, relevant literature reviews were searched in 3 databases to provide evidence. Subsequently, an initial consensus voting list on acupuncture as an adjunctive therapy for cardiac arrhythmias was derived from the clinical investigation and literature review. Finally, 30 authoritative experts reached a consensus on the key issues of the voting list by a three-round modified Delphi survey. Consensus was defined when >80% agreement was achieved.

Results

Following the three-round Delphi survey, there were 32 items (91.43%) finally reaching consensus, including the following 5 domains: (I) the benefits of acupuncture for the appropriate population; (II) the general therapeutic principle; (III) the acupuncture strategy; (IV) the relevant adverse events; (V) others.

Conclusions

Consensus was achieved on some key elements. Given the lack of guidelines and the substantial heterogeneity of previous studies, these recommendations are of value in providing guidance for clinical practice of acupuncturists and in assisting patients with arrhythmia to obtain standardized acupuncture treatment. It also pointed out some problems that need to be carefully explored in future studies.

The effects of frequency-specific, non-invasive, median nerve stimulation on food-related attention and appetite

Median nerve stimulation (MNS) in the existing literature has been used for treating gastrointestinal disorders and amelioration of nausea and vomiting. Recently, studies have shown that MNS can also exert effects on olfactory performances and corresponding anatomical regions through the activation of vagal pathways. This study aimed to test effects of specific frequencies of MNS on food-related attention and appetite. The experiment used an odourised, dot probe task for testing food-related attention and a combination of behavioural (i.e., visual analogue scales; VAS) and physiological approaches (i.e., electrocardiograph; ECG - root mean square of successive differences between normal heartbeats-RMSSD: parasympathetic nervous system activation (RMSSD), stress index-SI: sympathetic nervous system activation) for measuring hunger, appetite, and satiation. Twenty-four healthy, male adults completed a VAS and dot probe task before and after receiving either 40 Hz-, 80 Hz-, 120 Hz MNS or sham (control) across four different sessions with continuous ECG recording throughout each session. Data from the dot probe task were analysed using repeated-measures ANOVA, while pair-wise tests were used for ECG recordings and VAS. Improvements on the dot probe task, not specific to odour-food congruence were found after 40 Hz MNS (p-value = 0.048; strong effect size (0.308 partial eta squared)) while increased ratings of hunger (VAS) (p-value = 0.03, small effect size (0.47 Cohen-D)) and RMSSD scores (p-value < 0.001; medium effect size (0.76 Cohen-D)) were found after 120 Hz MNS. These findings implore further testing of MNS frequency parameters on improving RMSSD, a characteristic marker of measuring parasympathetic/autonomic nervous system activation pertaining to the vagal network. Furthermore, improving sympathovagal balance is associated with cardiovascular benefits in numerous health-related conditions such as obesity, hypertension and diabetes.

Hypothesis paper: electroacupuncture targeting the gut-brain axis to modulate neurocognitive determinants of eating behavior-toward a proof of concept in the obese minipig model

Acupuncture has thousands of years of history and perspective for the treatment of many health problems and disorders. Beneficial effects of acupuncture on obesity have been demonstrated at various levels in animals and clinical trials, with almost no adverse effect, even when combined with local electrical stimulation, i.e., electroacupuncture (EA), a way to potentiate the effects of acupuncture. However, there is still scattered evidence about the impact of EA on brain functions related to the control of eating behavior, and notably on the gut-brain axis mechanisms involved in these putative central modulations. During the past 10 years, we have described a convincing diet-induced obese minipig model, and successfully implemented brain imaging and neurocognitive approaches to challenge mechanistic hypotheses and innovative therapeutic strategies. In the present article, we propose to confront the current literature on the acupuncture and EA effects on the gut-brain axis and obesity with the latest developments in nutrition and neuroscience research using the minipig model. Our aims are to (a) elaborate functional hypotheses on the gut-brain mechanisms underlying EA effects on obesity, and especially on the role of the vagus nerve, and (b) present the rational for testing these hypotheses in the minipig model.