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JACC. Clinical Electrophysiology Jun 2024The autonomic nervous system plays an important role in atrial fibrillation (AF) and hypertension. Renal denervation (RDN) lowers blood pressure (BP), but its role in AF...
BACKGROUND
The autonomic nervous system plays an important role in atrial fibrillation (AF) and hypertension. Renal denervation (RDN) lowers blood pressure (BP), but its role in AF is poorly understood.
OBJECTIVES
The purpose of this study was to investigate whether RDN reduces AF recurrence after pulmonary vein isolation (PVI).
METHODS
This study randomized patients from 8 centers (United States, Germany) with drug-refractory AF for treatment with PVI+RDN vs PVI alone. A multielectrode radiofrequency Spyral catheter system was used for RDN. Insertable cardiac monitors were used for continuous rhythm monitoring. The primary efficacy endpoint was ≥2 minutes of AF recurrence or repeat ablation during all follow-up. The secondary endpoints included atrial arrhythmia (AA) burden, discontinuation of class I/III antiarrhythmic drugs, and BP changes from baseline.
RESULTS
A total of 70 patients with AF (52 paroxysmal, 18 persistent) and uncontrolled hypertension were randomized (RDN+PVI, n = 34; PVI, n = 36). At 3.5 years, 26.2% and 21.4% of patients in RDN+PVI and PVI groups, respectively, were free from the primary efficacy endpoint (log rank P = 0.73). Patients with mean ≥1 h/d AA had less daily AA burden after RDN+PVI vs PVI (4.1 hours vs 9.2 hours; P = 0.016). More patients discontinued class I/III antiarrhythmic drugs after RDN+PVI vs PVI (45% vs 14%; P = 0.040). At 1 year, systolic BP changed by -17.8 ± 12.8 mm Hg and -13.7 ± 18.8 mm Hg after RDN+PVI and PVI, respectively (P = 0.43). The composite safety endpoint was not significantly different between groups.
CONCLUSIONS
In patients with AF and uncontrolled BP, RDN+PVI did not prevent AF recurrence more than PVI alone. However, RDN+PVI may reduce AF burden and antiarrhythmic drug usage, but this needs further prospective validation.
PubMed: 38934973
DOI: 10.1016/j.jacep.2024.04.035 -
Zhurnal Nevrologii I Psikhiatrii Imeni... 2024To compare the effect of stage 3 fragmentation and the paradoxical phase of night sleep on melatonin (MT) secretion, and to evaluate the effects of changes in autonomic...
OBJECTIVE
To compare the effect of stage 3 fragmentation and the paradoxical phase of night sleep on melatonin (MT) secretion, and to evaluate the effects of changes in autonomic balance and activation reactions that occur in the orthodox and paradoxical phases of sleep.
MATERIAL AND METHODS
Fifteen healthy men participated in three sessions: with stage 3 fragmentation, with fragmentation of paradoxical sleep, and in a control experiment in which sleep was not disturbed. In each experiment, 7 saliva samples were collected in the evening, at night and in the morning and the MT content was determined. Heart rate variability was analyzed using an electrocardiogram and autonomic balance was assessed.
RESULTS
Sleep fragmentation was accompanied by activation reactions and reduced the duration of stage 3 and paradoxical phase sleep by 50% and 51% in the corresponding sessions. Fragmentation of paradoxical sleep also led to an increase in the duration of night wakefulness. Sleep disturbances caused an increase in MT secretion in the second half of the night and in the morning, especially pronounced in sessions with fragmentation of paradoxical sleep, in which upon awakening MT was 1.8 times higher than in the control. Stage 3 fragmentation was accompanied by increased sympathetic activation, while fragmentation of paradoxical sleep did not cause autonomic shifts. The subjects were divided into 2 clusters: with high and low MT in night and morning saliva samples. In all sessions, subjects with high MT had 1.7-2 times longer duration of night wakefulness; in sessions with fragmentation, they had significantly more activations in the paradoxical phase of sleep.
CONCLUSION
Night sleep disturbances cause an increase in MT secretion, especially pronounced during the fragmentation of the paradoxical phase. An increase in MT levels does not depend on changes in autonomic balance and is apparently associated with activation of the serotonergic system, which accompanies disturbances in the depth and continuity of sleep.
Topics: Humans; Melatonin; Male; Sleep, REM; Adult; Saliva; Sleep Deprivation; Sleep, Slow-Wave; Young Adult; Heart Rate; Autonomic Nervous System; Wakefulness
PubMed: 38934663
DOI: 10.17116/jnevro202412405226 -
Cureus Jun 2024This study investigated the pathogenesis and pathophysiology of chronic epipharyngitis, which presents a variety of symptoms, with a focus on autonomic neuropathy... (Review)
Review
This study investigated the pathogenesis and pathophysiology of chronic epipharyngitis, which presents a variety of symptoms, with a focus on autonomic neuropathy symptoms, and also investigated the literature for information on EAT, which is useful as a treatment method. The mechanism of action of EAT has recently been clarified in terms of its immune system-stimulating and endocrine system-stimulating effects. However, the autonomic nerve-stimulating effects of EAT are still largely unexplained. This study was conducted to collect and integrate previous studies and papers focusing on the autonomic nerve-stimulating effects of EAT and to provide insight into the still not fully elucidated autonomic nerve-stimulating effects of EAT on chronic epipharyngitis. The local stimulating effects of zinc chloride and the bleeding and pain effects of EAT are also summarized, suggesting that EAT exerts its therapeutic effects through the interaction of the immune system, the endocrine system, and the autonomic nervous system. It is important to determine which mechanism is predominantly involved in each case of chronic epipharyngitis and to utilize it in treatment. Elucidating the effects of EAT on the autonomic nervous system will be an important guideline in determining the treatment strategy for chronic epipharyngitis.
PubMed: 38933344
DOI: 10.7759/cureus.63182 -
Neurobiology of Stress Jul 2024High stress is a key risk factor for alcohol use disorder (AUD) and often accompanied by physiological dysregulation including autonomic nervous system (ANS)...
High stress is a key risk factor for alcohol use disorder (AUD) and often accompanied by physiological dysregulation including autonomic nervous system (ANS) disruptions. However, neural mechanisms underlying drinking behaviors associated with stress and ANS disruptions remain unclear. The current study aims to understand neural correlates of stress, ANS disruptions, and subsequent alcohol intake in social drinkers with risky drinking. Using functional magnetic resonance imaging (fMRI), we investigated brain and heart rate (HR) autonomic responses during brief exposure to stress, alcohol, and neutral cues utilizing a well-validated, individualized imagery paradigm in 48 social drinkers of which 26 reported high-risk drinking (HD) while 22 reported low-risk drinking (LD) patterns. Results indicated that HD individuals showed stress and ANS disruptions with increased basal HR, stress-induced craving, and decreased brain response to stress exposure in frontal-striatal regions including the ventromedial prefrontal cortex (VmPFC), anterior cingulate cortex, striatum, insula, and temporal gyrus. Furthermore, whole-brain correlation analysis indicated that greater basal HR was associated with hypoactive VmPFC, but hyperactive medulla oblongata (MOb) responses during stress, with an inverse association between activity in the VmPFC and Mob (whole-brain corrected (WBC), p < 0.05). Functional connectivity with the MOb as a seed to the whole brain indicated that HD versus LD had decreased functional connectivity between the VmPFC and MOb during stress (WBC, p < 0.05). In addition, those with more compromised functional connectivity between the VmPFC and MOb during stress consumed greater amount of alcohol beverage during an experimental alcohol taste test conducted on a separate day, as well as in their self-reported weekly alcohol intake. Together, these results indicate that stress-related, dysfunctional VmPFC control over brain regions of autonomic arousal contributes to greater alcohol motivation and may be a significant risk factor for hazardous alcohol use in non-dependent social drinkers. Findings also suggest that restoring VmPFC integrity in modulating autonomic arousal during stress may be critical for preventing the development of AUD.
PubMed: 38933283
DOI: 10.1016/j.ynstr.2024.100645 -
Frontiers in Cardiovascular Medicine 2024Aging is the most significant contributor to the increasing prevalence of atrial fibrillation (AF). Dysbiosis of gut microbiota has been implicated in age-related...
OBJECTIVE
Aging is the most significant contributor to the increasing prevalence of atrial fibrillation (AF). Dysbiosis of gut microbiota has been implicated in age-related diseases, but its role in AF development remains unclear. This study aimed to investigate the correlations between changes in the autonomic nervous system, short-chain fatty acids (SCFAs), and alterations in gut microbiota in aged rats with AF.
METHODS
Electrophysiological experiments were conducted to assess AF induction rates and heart rate variability in rats. 16S rRNA gene sequences extracted from fecal samples were used to assess the gut microbial composition. Gas and liquid chromatography-mass spectroscopy was used to identify SCFAs in fecal samples.
RESULTS
The study found that aged rats exhibited a higher incidence of AF and reduced heart rate variability compared to young rats. Omics research revealed disrupted gut microbiota in aged rats, specifically a decreased Firmicutes to Bacteroidetes ratio. Additionally, fecal SCFA levels were significantly lower in aged rats. Importantly, correlation analysis indicated a significant association between decreased SCFAs and declining heart rate variability in aged rats.
CONCLUSIONS
These findings suggest that SCFAs, as metabolites of gut microbiota, may play a regulatory role in autonomic nervous function and potentially influence the onset and progression of AF in aged rats. These results provide novel insights into the involvement of SCFAs and autonomic nervous system function in the pathogenesis of AF. These results provide novel insights into the involvement of SCFAs and autonomic nervous system function in the pathogenesis of AF.
PubMed: 38932988
DOI: 10.3389/fcvm.2024.1394929 -
Sensors (Basel, Switzerland) Jun 2024Heart rate variability (HRV) is related to cardiac vagal control and emotional regulation and an index for cardiac vagal control and cardiac autonomic activity. This...
Heart rate variability (HRV) is related to cardiac vagal control and emotional regulation and an index for cardiac vagal control and cardiac autonomic activity. This study aimed to develop the Taiwan HRV normative database covering individuals aged 20 to 70 years and to assess its diagnosing validity in patients with major depressive disorder (MDD). A total of 311 healthy participants were in the HRV normative database and divided into five groups in 10-year age groups, and then the means and standard deviations of the HRV indices were calculated. We recruited 272 patients with MDD for cross-validation, compared their HRV indices with the normative database, and then converted them to Z-scores to explore the deviation of HRV in MDD patients from healthy groups. The results found a gradual decline in HRV indices with advancing age in the HC group, and females in the HC group exhibit higher cardiac vagal control and parasympathetic activity than males. Conversely, patients in the MDD group demonstrate lower HRV indices than those in the HC group, with their symptoms of depression and anxiety showing a negative correlation with HRV indices. The Taiwan HRV normative database has good psychometric characteristics of cross-validation.
Topics: Humans; Heart Rate; Depressive Disorder, Major; Male; Female; Adult; Middle Aged; Aged; Autonomic Nervous System; Young Adult; Databases, Factual; Taiwan; Electrocardiography; Heart
PubMed: 38931788
DOI: 10.3390/s24124003 -
Nutrients Jun 2024Guarana (GUA), a Brazilian seed extract, contains caffeine and other bioactive compounds that may have psychoactive effects. To assess the acute effects of GUA compared... (Randomized Controlled Trial)
Randomized Controlled Trial
Guarana (GUA), a Brazilian seed extract, contains caffeine and other bioactive compounds that may have psychoactive effects. To assess the acute effects of GUA compared to a low dose of caffeine (CAF) on cognitive and mood parameters, twenty participants completed a double-blind, crossover experiment where they ingested capsules containing the following: (1) 100 mg CAF, (2) 500 mg GUA containing 130 mg caffeine, or (3) placebo (PLA). Cognitive tests (Simon and 2N-Back Task) were performed at the baseline (pre-ingestion) and 60 min after ingestion. The response time for the cognitive tests and heart rate variability were unaffected ( > 0.05) by treatment, although 2N-Back was overall faster ( = 0.001) across time. The accuracy in the 2N-Back Task showed a significant interaction effect ( = 0.029) due to higher post-ingestion versus pre-ingestion levels ( = 0.033), but only with the PLA. The supplements also had no effect on cognitive measures following physical fatigue ( = 11). There was an interaction effect on perceived mental energy, where the pre-ingestion of GUA had lower mental pep ratings compared to post-ingestion ( = 0.006) and post-exercise ( = 0.018) levels. Neither the acute ingestion of GUA nor low dose of CAF influenced cognitive performance or provided consistent benefit on mood or mental workload through vagal modulation. Additional investigations are beneficial to determining the lowest effective dose for CAF or GUA to influence mood and/or cognitive performance.
Topics: Humans; Caffeine; Paullinia; Male; Cross-Over Studies; Double-Blind Method; Cognition; Adult; Young Adult; Female; Heart Rate; Affect; Vagus Nerve; Plant Extracts; Dietary Supplements
PubMed: 38931247
DOI: 10.3390/nu16121892 -
Life (Basel, Switzerland) Jun 2024Stress is recognized as a significant trigger and exacerbator of various medical conditions, particularly in the field of cardiovascular disease (CVD). Given that heart... (Review)
Review
Stress is recognized as a significant trigger and exacerbator of various medical conditions, particularly in the field of cardiovascular disease (CVD). Given that heart rate variability (HRV) offers insight into the functioning of the autonomic nervous system and has been identified as a predictive factor for increased cardiovascular mortality, exploring the correlation between stress and HRV is pertinent. We systematically reviewed trials where researchers investigated the effects of stress-reducing interventions on biomarkers and time-domain/frequency-domain parameters of HRV in CVD. Eligible studies underwent meta-analysis utilizing a random-effects model. The meta-analysis showed overall beneficial effects of stress-reducing interventions on HRV for the standard deviation of Normal-to-Normal intervals (SDNN) in short-term and 24 h assessments, as well as for the low-frequency power (LF) in short-term assessment. Overall effect sizes were notably high and showed significant -values (short-term SDNN: MD = 6.43, = 0.01; 24 h SDNN: MD = 10.92, = 0.004; short-term LF: MD = 160.11, < 0.001). Our findings highlight the significant impact of stress-reducing interventions in modulating HRV by influencing short-term SDNN and LF parameters, as well as the 24 h assessment of SDNN. These results emphasize the importance of stress-reducing measures in lowering the risk of further progression in CVD and improving patient outcomes.
PubMed: 38929732
DOI: 10.3390/life14060749 -
Diagnostics (Basel, Switzerland) Jun 2024Thyroid hormones have a pivotal role in controlling metabolic processes, cardiovascular function, and autonomic nervous system activity. Hypothyroidism, a prevalent...
Thyroid hormones have a pivotal role in controlling metabolic processes, cardiovascular function, and autonomic nervous system activity. Hypothyroidism, a prevalent endocrine illness marked by inadequate production of thyroid hormone, has been linked to different cardiovascular abnormalities, including alterations in heart rate variability (HRV). The study included 110 patients with hypothyroid disorder. Participants underwent clinical assessments, including thyroid function tests and HRV analysis. HRV, a measure of the variation in time intervals between heartbeats, serves as an indicator of autonomic nervous system activity and cardiovascular health. The HRV values were acquired using continuous 24-h electrocardiogram (ECG) monitoring in individuals with hypothyroidism, as well as after a treatment period of 3 months. All patients exhibited cardiovascular symptoms like palpitations or fatigue but showed no discernible cardiac pathology or other conditions associated with cardiac disease. The findings of our study demonstrate associations between hypothyroidism and alterations in heart rate variability (HRV) parameters. These results illustrate the possible influence of thyroid dysfunction on the regulation of cardiac autonomic function.
PubMed: 38928676
DOI: 10.3390/diagnostics14121261 -
International Journal of Molecular... Jun 2024The influence of accelerated electrons on neuronal structures is scarcely explored compared to gamma and X-rays. This study aims to investigate the effects of...
The influence of accelerated electrons on neuronal structures is scarcely explored compared to gamma and X-rays. This study aims to investigate the effects of accelerated electron radiation on some pivotal neurotransmitter circuits (cholinergic and serotonergic) of rats' myenteric plexus. Male Wistar rats were irradiated with an electron beam (9 MeV, 5 Gy) generated by a multimodality linear accelerator. The contractile activity of isolated smooth muscle samples from the gastric corpus was measured. Furthermore, an electrical stimulation (200 μs, 20 Hz, 50 s, 60 V) was performed on the samples and an assessment of the cholinergic and serotonergic circuits was made. Five days after irradiation, the recorded mechanical responses were biphasic-contraction/relaxation in controls and contraction/contraction in irradiated samples. The nature of the contractile phase of control samples was cholinergic with serotonin involvement. The relaxation phase involved ACh-induced nitric oxide release from gastric neurons. There was a significant increase in serotonergic involvement during the first and second contractile phases of the irradiated samples, along with a diminished role of acetylcholine in the first phase. This study demonstrates an increased involvement of serotonergic neurotransmitter circuits in the gastric myenteric plexus caused by radiation with accelerated electrons.
Topics: Animals; Myenteric Plexus; Male; Rats; Rats, Wistar; Stomach; Electrons; Muscle, Smooth; Serotonin; Muscle Contraction; Acetylcholine; Nitric Oxide
PubMed: 38928511
DOI: 10.3390/ijms25126807