Effect of ultrasound-guided stellate ganglion block on cerebral oxygen metabolism and S100B protein during carotid endarterectomy

OBJECTIVE

To investigate the effect of ultrasound-guided stellate ganglion block (SGB) on cerebral oxygen metabolism and serum S100B during carotid endarterectomy (CEA).

METHODS

Patients who were prospectively enrolled to receive CEA under elective general anesthesia were randomized into an SGB group and a control group (ChiCTR2000033385). Before anesthesia, the SGB group underwent ipsilateral SGB under ultrasound guidance, while the control group did not. Ultrasound-guided right subclavian internal jugular vein catheterization was performed under general anesthesia. Mean arterial pressure (MAP) and heart rate (HR) were monitored at various time points (T0-T4). Arterial and internal jugular venous bulb blood were collected for blood gas analysis, determining jugular venous oxygen saturation (SjvO2), arteriovenous oxygen difference (AVDO2), cerebral oxygen extraction ratio (COER), lactate production rate (LPR), and lactate-oxygen index (LOI). The serum concentration of S100B in the internal jugular venous bulb at each time point was measured.

RESULTS

The results revealed significantly lower HR during anesthesia induction and surgery in the SGB group, with more stable MAP and HR during endotracheal intubation and surgery compared to the control group (P<0.05). The control group exhibited decreases at T3 and a slight increase at T4. SjvO2 was significantly higher in the SGB group, while AVDO2 and COER gradually decreased over time, but they were significantly higher in the control group (P<0.05). LPR and LOI in both groups peaked at T3 and were significantly different between T4 and T2 (P<0.05). Serum S100B levels in both groups rose and then decreased at each time point, but they were consistently lower in the SGB group (P<0.05).

CONCLUSION

SGB before CEA effectively suppresses the stress response, maintains intraoperative hemodynamic stability, improves brain tissue oxygen supply, and demonstrates a neuroprotective effect.

Stellate Ganglion Block for the Treatment of COVID-19-Induced Olfactory Dysfunction: A Prospective Pilot Study

OBJECTIVE

The objective of this study was to explore the safety and feasibility of stellate ganglion blocks (SGBs) to treat persistent COVID-19-induced olfactory dysfunction (OD). Secondarily, the goal was to determine effect sizes to plan a future randomized clinical trial.

STUDY DESIGN

Prospective case series.

SETTING

Quaternary Care Academic Medical Center.

METHODS

In this single-arm pilot trial, adult participants with a COVID-19 diagnosis ≥ 12 months prior to enrollment with OD underwent bilateral SGBs. Subjects were followed for 1 month after completion of SGB. The primary outcome measure was the change in the Clinical Global Impression-Improvement Scale for smell loss. Secondary outcome measures included changes in the University of Pennsylvania Smell Identification Test (UPSIT) and Olfactory Dysfunction Outcomes Rating (ODOR).

RESULTS

Twenty participants were enrolled with a mean (SD) age of 46 (11) years and a mean (SD) duration of OD of 21 (5) months. At 1 month, 10 (50%) participants experienced at least slight subjective improvement in their OD, 11 (55%) attained a clinically meaningful improvement in smell identification using the UPSIT, and 7 (35%) achieved a clinically meaningful improvement in olfactory-specific quality of life (QoL) measured by the ODOR. The median difference between UPSIT scores at baseline and 1 month was 6 (95% confidence interval: 3-11), exceeding the minimal clinically important difference of 4. There were no serious adverse events.

CONCLUSION

Sequential SGBs for COVID-19-associated OD were safe and associated with modest improvements in subjective olfaction, odor identification, and olfactory-specific QoL. A placebo-controlled trial is warranted to determine the efficacy of SGBs for COVID-19-associated OD.

Autonomic Modulation of Atrial Fibrillation

The autonomic nervous system plays a vital role in cardiac arrhythmias, including atrial fibrillation (AF). Therefore, reducing the sympathetic tone via neuromodulation methods may be helpful in AF control. Myocardial ischemia is associated with increased sympathetic tone and incidence of AF. It is an excellent disease model to understand the neural mechanisms of AF and the effects of neuromodulation. This review summarizes the relationship between autonomic nervous system and AF and reviews methods and mechanisms of neuromodulation. This review proposes that noninvasive or minimally invasive neuromodulation methods will be most useful in the future management of AF.

Efficacy of stellate ganglion interventions for complex regional pain syndrome in the upper limb-A systematic review and meta-analysis

Background and Aims

Stellate ganglion (SG) interventions for treating upper limb complex regional pain syndrome (CRPS) have been reported in studies. However, more substantial evidence is required to reach a consensus on its analgesic efficacy. To the best of our knowledge, no systematic review demonstrating the effectiveness of SG intervention for upper limb CRPS has been reported. Hence, this meta-analysis was done to ascertain the efficacy of SG intervention in managing patients with upper limb CRPS.

Methods

A database search of PubMed, Cochrane, Embase, Scopus and Google Scholar was done for articles published between January 2001 and December 2021. Two independent reviewers extracted data from the included studies, and the studies were evaluated for any potential risk of bias, and a meta-analysis was performed.

Results

Eight studies were included in the qualitative synthesis, four were randomised controlled trials (RCTs), and the rest were non-RCTs. Six studies were assessed quantitatively. A significant reduction in pain scores post-intervention, up to two weeks, and four to 28 weeks after the procedure was observed, although the included studies exhibited marked heterogeneity. Qualitative analysis of these studies revealed an overall improvement in disability scores and functionality as assessed by an improved range of motion. Most studies reported no complications or only short-term minor complications after the procedure.

Conclusion

Stellate ganglion interventions improve pain and disability scores with self-limiting short-term complications and no long-term complications. However, further studies with a large sample size are required to validate this treatment modality.

The Efficacy of Stellate Ganglion Blockade in Herpetic Neuralgia: A Case Report

The varicella-zoster virus can reactivate in patients with impaired cell-mediated immunity, resulting in herpes zoster (HZ) and sometimes in herpetic neuralgia (HN). Stellate ganglion blockade (SGB) has been studied for the treatment of HN and postherpetic neuralgia (PHN), but its effectiveness in preventing PHN in patients with acute HZ is not well-established. Here, we present a case of a 75-year-old woman who underwent SGB for HN of the right upper limb. The patient had been treated with antivirals and various analgesics, but adverse effects due to analgesics led to discontinuation of them. After the first application of SGB, the patient experienced significant pain reduction, and after a second application, complete remission of pain was achieved. Nine months later, the patient remained symptom-free and without PHN. The therapeutic potential of SGB in the treatment of HN and its role in preventing PHN requires further investigation.

Phrenic nerve block combined with stellate ganglion block for postoperative intractable hiccups: a case report

Postoperative intractable hiccups slow patient recovery and generate multiple adverse effects, highlighting the importance of investigating the pathogenesis and terminating the hiccups in a timely manner. At present, medical and physical therapies account for the main treatments. We encountered a case in which postoperative intractable hiccups after biliary T-tube drainage removal ceased with the application of an ultrasound-guided block of the unilateral phrenic nerve and stellate ganglion. No complications developed, and the therapeutic effect was remarkable. To our knowledge, this approach has not been reported to date. Simultaneously blocking the phrenic nerve and stellate ganglion may be a treatment option for intractable hiccups.

Pulsed radiofrequency to stellate ganglion for brachial plexus injury-induced complex regional pain syndrome: A case series

Brachial plexus injury (BPI) occurs commonly in young adults following trauma. This may result in the development of complex regional pain syndrome (CRPS) following injury, which is difficult to treat. We present a group of patients with CRPS secondary to BPI. These patients were managed with neuromodulation of the stellate ganglion (SG) with pulsed radiofrequency (PRF) and followed up for a period of 3 months to assess for pain relief and a decrease in the intake of medications after the intervention. PRF to SG was found to have significant pain relief lasting around three months.

Can stellate ganglion blockage be an alternative treatment for refractory ventricular arrhythmias: Case series

INTRODUCTION

Ventricular tachycardia (VT) and ventricular fibrillation (VF) are life-threatening conditions which increase in frequency over the years. Electrical storm (ES) is defined as the occurrence of 3 or more continuous ventricular arrhythmia. The sympathetic nervous system has an important role in Ventricular arrythmias (VA) and is the target of treatment. Studies show that stellate ganglion blockade (SGB) can reduce cardiac sympathetic tone and is an alternative bridge therapy in VAs.

PATIENT CONCERNS

Among the patients who were admitted to the hospital with the complaints of general condition disorder and palpitation.

DIAGNOSIS

Patients were referred to the Cardiology department and diagnosed VA and ES. Patients who applied to the Cardiology Department with the diagnosis of VA or ES and did not benefit from antiarrhythmic drug therapy were selected and evaluated by a team of 2 anesthesiologists (cardiothoracic and pain specialists) and 2 cardiologists (1 of whom is an electrophysiology specialist).

INTERVENTION

In our study, ultrasound (USG) guided left SGB was applied to 10 VA and ES patients with implantable cardiac defibrillator (ICD). The 6-month results of the patients were evaluated retrospectively. For blockage, the solution was prepared by adding 8 mg dexamethasone, 40 mg lidocaine and 10 mg bupivacaine to 10 mL with physiological saline. The success of the procedure was evaluated with the development of Horner syndrome in the left eye.

OUTCOMES

Resistant VA developed in 2 of 10 patients who had left SGB due to VF/VT ES and were excluded from the study. One (1) month after the procedure it was seen that there was a statistically significant decrease in the number of shocks in 8 patients in the 6th month controls compared to the pre-procedure. The number of VES in the 1st and 6th months of the patients was also statistically significantly decreased compared to the pre-SSD (P = .01, P = .01, P = .01, respectively).

CONCLUSION

Unilateral USG-guided SGB application is an effective and safe method in patients with ES and VA. Long-term results can be satisfactory in successful responders in whom SGB is performed with a combination of local anesthetic and steroid.

Effects of right stellate ganglion block combined with topical anesthesia on heart rate variability in awake patients receiving tracheal intubation

Objective

General anesthesia is commonly performed with tracheal intubation. We aimed to evaluate the effects of right stellate ganglion block combined with topical anesthesia on the heart rate variability in awake patients receiving tracheal intubation.

Methods

A total of 120 eligible patients were equally divided into observation and control groups using a random number table. The observation group underwent right stellate ganglion block combined with topical anesthesia. The excellent and good rate of anesthesia, indicators of vital signs and heart rate variability, incidence rate of adverse reactions, success rate and time consumption of tracheal intubation, postoperative resuscitation and cognitive function score of the two groups were compared.

Results

The systolic pressure, diastolic pressure and heart rate significantly increased in both groups during tracheal intubation compared with those before tracheal intubation, which they were lower in the observation group than those in the control group during tracheal intubation (P<0.05). Low-frequency power, ratio of low-frequency power to high-frequency power and heart rate variability index significantly decreased in both groups during tracheal intubation compared with those before tracheal intubation (P<0.05).

Conclusion

Right stellate ganglion block combined with topical anesthesia can work well for awake patients during tracheal intubation.

Local Injection for Treating Mood Disorders (LIFT-MOOD): A Pilot Feasibility RCT of Stellate Ganglion Block for Treatment-Resistant Depression

Background

With nearly one-third of patients with major depressive disorder being resistant to available antidepressants, there is a need to develop new treatments for this population. Stellate ganglion block (SGB) is a procedure used to block sympathetic input to the central autonomic system; it has been administered to treat several conditions, including pain. Recently, indications for SGB have extended and the potential benefits for psychiatric disorders are under investigation.

Methods

The Local Injection For Treating Mood Disorders (LIFT-MOOD) study investigated the feasibility of a trial of 2 right-sided injections of bupivacaine 0.5% (7 mL) at the stellate ganglion in participants with treatment-resistant depression (TRD) using a randomized, placebo-controlled, pilot trial. Ten participants were randomized in a 1:1 allocation to receive active treatment or placebo (saline). Primary feasibility outcomes included recruitment rate, withdrawal, adherence, missing data, and adverse events. As a secondary, exploratory objective, we explored the efficacy of SGB in improving symptoms of depression by calculating the change in scores from baseline to follow-up on day 42 for each treatment group.

Results

The recruitment rate was reasonable and sufficient, retention and adherence were high, missing data were low, and adverse events were mild and temporary. Both treatment groups demonstrated decreases in Montgomery-Åsberg Depression Rating Scale scores, compared to baseline, by the end of the study.

Conclusion

This study supports the feasibility of a confirmatory trial of SGB in participants with TRD. Conclusions regarding efficacy cannot be made based on this preliminary study due to the small number of participants who completed active treatment. Larger-scale randomized controlled trials with long-term follow-ups and alternate sham procedures are needed to assess the efficacy and duration of symptom improvement with the use of SGB in TRD.

Stellate Ganglion Block for Long COVID Symptom Management: A Case Report

Stellate ganglion block (SGB) is gaining increasing acceptance as a treatment modality for various medical conditions. It works by blocking neuronal transmissions which in turn alleviates sympathetically-driven disease processes. Many of the prolonged sequelae of long COVID are thought to be mediated by dysregulation of the autonomic nervous system, and SGB is being investigated as a potential option for symptomatic management of long COVID. This case report demonstrates the efficacy of SGB in a previously healthy patient for the management of long COVID symptoms including fatigue, post-exertional malaise, shortness of breath, and gastrointestinal symptoms. .

Metrics of high cofluctuation and entropy to describe control of cardiac function in the stellate ganglion

Stellate ganglia within the intrathoracic cardiac control system receive and integrate central, peripheral, and cardiopulmonary information to produce postganglionic cardiac sympathetic inputs. Pathological anatomical and structural remodeling occurs within the neurons of the stellate ganglion (SG) in the setting of heart failure (HF). A large proportion of SG neurons function as interneurons whose networking capabilities are largely unknown. Current therapies are limited to targeting sympathetic activity at the cardiac level or surgical interventions such as stellectomy, to treat HF. Future therapies that target the SG will require understanding of their networking capabilities to modify any pathological remodeling. We observe SG networking by examining cofluctuation and specificity of SG networked activity to cardiac cycle phases. We investigate network processing of cardiopulmonary transduction by SG neuronal populations in porcine with chronic pacing-induced HF and control subjects during extended in-vivo extracellular microelectrode recordings. We find that information processing and cardiac control in chronic HF by the SG, relative to controls, exhibits: (i) more frequent, short-lived, high magnitude cofluctuations, (ii) greater variation in neural specificity to cardiac cycles, and (iii) neural network activity and cardiac control linkage that depends on disease state and cofluctuation magnitude.

Anatomical Variation of the Sympathetic Trunk and Aberrant Rami Communicantes and their Clinical Implications

Surgical interventions involving the sympathetic trunk are increasingly performed to alleviate symptoms of several disorders such as hyperhidrosis. Anatomical variation has been highlighted as one of the main causes behind surgical failure and symptoms recurrence following surgeries conducted on the chain or its surroundings. This study therefore aimed to record anatomical variants within spinal segments C8-T10 of the sympathetic trunk. Thirty Thiel-embalmed cadavers were investigated bilaterally. The stellate ganglion was recorded on 29 sides. Its size was significantly greater in males and on the right side when the coalescence extended to the subsequent ganglion. The intrathoracic nerve of Kuntz was observed on 21 sides and was significantly more prevalent in males. There was a significant positive association between the presence of this nerve and the descending ramus in the first intercostal space. Aberrant rami found between spinal root C8 and the ventral ramus of the first intercostal nerve were introduced as rami communicantes superi. Aberrant rami communicantes were recorded 50 times in total, of which 70% were found in males. Descending rami showed the highest prevalence in upper intercostal levels, especially in males within the first intercostal space. Aberrant neuronal pathways in upper levels were significantly more prevalent when the stellate ganglion was present. The scientific literature has proven to be stochastic as results were significantly higher in past studies in regard to some sympathetic variants. Anatomical findings of the current study as well as the inconsistency of previous data should be acknowledged and considered for better surgical planning.

Comparison of lidocaine and ropivacaine stellate ganglion blockade in treating upper limb postherpetic neuralgia

To provide a basis for treating postherpetic neuralgia (PHN), we compared the efficacy of lidocaine and ropivacaine stellate ganglion block (SGB) in PHN treatment in the upper limbs.Data from 252 patients with upper-limb PHN were retrospectively analyzed. The lidocaine group (n = 118) was treated with oral pregabalin capsules 75 mg twice a day, tramadol hydrochloride sustained release tablets 100 mg twice a day, and amitriptyline 25 mg once at night combined with ultrasound-guided lidocaine SGB; the ropivacaine group (n = 134) was orally administered the same medicines combined with ultrasound-guided ropivacaine SGB. The visual analog scale (VAS), self-rating anxiety scale (SAS), and adverse reactions were compared between the groups before treatment and at 1 week, 1 month, and 3 months after treatment.There were no significant differences between the lidocaine and ropivacaine groups in terms of sex, age, height, weight, and pain duration (P > .05). There was no significant difference between the groups in VAS and SAS scores before treatment (P > .05). At 1 week, 1 month, and 3 months after ultrasound-guided SGB treatment, the VAS and SAS scores were significantly lower in the ropivacaine group than in the lidocaine group (P < .05). There were no significant differences between the groups in terms of adverse reactions (P > .05).For ultrasound-guided SGB treatment of upper limb PHN, ropivacaine is superior to lidocaine. Ultrasound-guided ropivacaine SGB is safe and effective for the treatment of upper limb PHN.

Stellate ganglion intervention for chronic pain: A review

Stellate ganglion (SG) intervention is currently widely being studied in many kinds of chronic pain. As one of the convenient ways to treat the sympathetic nervous system, the indications for stellate ganglion intervention (SGI) include complex regional pain syndrome, postherpetic neuralgia, cancer pain of different origins, orofacial pain, and so forth. SGI refers to the reversible or irreversible blocking of the cervical sympathetic trunk, cervical sympathetic ganglion, and their innervation range through noninvasive or minimally invasive treatment. Current treatment options include stellate ganglion block (SGB), SG pulsed radiofrequency, continuous radiofrequency treatment, and noninvasive SGB. In particular, SGB continues to be one of the most studied methods in chronic pain management. However, a single SGB usually provides only short-term effects; repeated SGB may result in complications such as hoarseness, light-headedness, and vessel or nerve injury. Meanwhile, the mechanism of SGI is still unclear. This review discusses the research progress of SGI methods, effectiveness, complications, and possible mechanisms in the management of chronic pain.

Abstract No. : ABS2262: Ultrasound guided continuous stellate ganglion block in peripheral vascular disease of upper limb - A case series

Background and Aims:

Stellate ganglion block relieves pain and improves perfusion in peripheral vascular disease(PVD) of upper limbs. Single shot stellate ganglion block often provides only short-term relief and repeated blocks are associated with tissue or neural damage and infections. Non-availability/affordability limits the use of thermal radiofrequency nerve ablation of the stellate ganglion.We report our experience of managing 46 cases of PVD of upper limb with continuous stellate ganglion block(CSGB).

Methods:

Six cases of PVD of left upper limb who presented with severe ischemic neuropathic pain and blackish discoloration of fingers were treated with ultrasound guided CSGB with infusion of 0.125% of bupivacaine at 5ml per hour for 5 days. All patients were assessed for intensity of pain using numerical rating scale (NRS), change of colour and peripheral pulsations before the procedure and 2, 4, 12 and 24 weeks after the procedure.

Results:

All the patients reported significant reduction in NRS scores, improvement in skin colour, healing of gangrenous lesions and return of peripheral pulsations at follow up visits.

Conclusion:

Continuous catheter infusion not only provides more sustained pain relief and emerges as a cost effective option in improving perfusion and aid wound healing.

A novel metric linking stellate ganglion neuronal population dynamics to cardiopulmonary physiology

Cardiopulmonary sympathetic control is exerted via stellate ganglia (SG); however, little is known about how neuronal firing patterns in the stellate ganglion relate to dynamic physiological function in the heart and lungs. We performed continuous extracellular recordings from SG neurons using multielectrode arrays in chloralose-anesthetized pigs (n = 6) for 8-9 h. Respiratory and left ventricular pressures (RP and LVP, respectively) and the electrocardiogram (ECG) were recorded concomitantly. Linkages between sampled spikes and LVP or RP were determined using a novel metric to evaluate specificity in neural activity for phases of the cardiac and pulmonary cycles during resting conditions and under various cardiopulmonary stressors. Firing frequency (mean 4.6 ± 1.2 Hz) varied spatially across the stellate ganglion, suggesting regional processing. The firing pattern of most neurons was synchronized with both cardiac (LVP) and pulmonary (RP) activity indicative of cardiopulmonary integration. Using the novel metric to determine cardiac phase specificity of neuronal activity, we found that spike density was highest during diastole and near-peak systole. This specificity was independent of the actual LVP or population firing frequency as revealed by perturbations to the LVP. The observed specificity was weaker for RP. Stellate ganglion neuronal populations exhibit cardiopulmonary integration and profound specificity toward the near-peak systolic phase of the cardiac cycle. This novel approach provides practically deployable tools to probe stellate ganglion function and its relationship to cardiopulmonary pathophysiology.NEW & NOTEWORTHY Activity of stellate ganglion neurons is often linking indirectly to cardiac function. Using novel approaches coupled with extended period of recordings in large animals, we link neuronal population dynamics to mechanical events occurring at near-peak systole. This metric can be deployed to probe stellate ganglion neuronal control of cardiopulmonary function in normal and disease states.

Stellate Ganglion Phototherapy Using Low-Level Laser: A Novel Rescue Therapy for Patients With Refractory Ventricular Arrhythmias

OBJECTIVES

This study investigates the effect of stellate ganglion (SG) phototherapy in healthy participants and assesses its efficacy in suppressing electrical storm (ES) refractory to antiarrhythmic drugs and catheter ablation.

BACKGROUND

Modulation of the autonomic nervous system has been shown to be an effective adjunctive therapy for ES.

METHODS

Ten-minute SG phototherapy was performed twice weekly for 4 weeks in 20 healthy volunteers. To evaluate the acute and chronic effects of SG phototherapy, heart rate variability and serum concentrations of adrenaline, noradrenaline, and dopamine were obtained before phototherapy, immediately after the first phototherapy session, after 8 sessions of phototherapy, and 3 months after the first phototherapy session. In addition, the efficacy of SG phototherapy was evaluated in 11 patients with ES refractory to medication, sedation, and catheter ablation.

RESULTS

In healthy participants, serum adrenaline concentration significantly decreased after phototherapy, whereas low-frequency power/high-frequency power significantly decreased during phototherapy. Moreover, the effect on heart rate variability did not last beyond 3 months. In the clinical pilot study, 7 patients had a suppression of ES after SG phototherapy; however, without maintenance therapy, 2 patients had a recurrence of ventricular arrhythmias. Furthermore, it did not control ES in 4 patients.

CONCLUSIONS

SG phototherapy reduced sympathetic activity and may be a safe and effective adjunctive therapy to control ES in some patients, but its long-term efficacy remains unknown. Chronic phototherapy might help reduce ES recurrence.

Sequential Supraclavicular Brachial Plexus and Stellate Ganglion Neurolysis for Upper Limb Pain in Metastatic Breast Cancer

Neuropathic pain in cancer can result in severe debilitation to a patient with limited treatment options. Interventional modalities like nerve destruction can provide relief but at the expense of motor paralysis. Sympathetic pain is often an undiagnosed and undertreated condition that may accompany cases of chronic pain. We describe a case of severe neuropathic pain in brachial plexopathy in a middle-aged woman caused by metastatic breast cancer that was managed by chemical neurolysis of brachial plexus. Residual pain was treated by neurolysis of stellate ganglion due to the presence of sympathetic pain. This case report highlights the importance of the dual nature of pain and its management by chemical neurolysis in severe refractory neuropathic and sympathetic mediated pain.

Recording Intrinsic Nerve Activity at the Sinoatrial Node in Normal Dogs With High-Density Mapping

BACKGROUND

It is known that autonomic nerve activity controls the sinus rate. However, the coupling between local nerve activity and electrical activation at the sinoatrial node (SAN) remains unclear. We hypothesized that we would be able to record nerve activity at the SAN to investigate if right stellate ganglion (RSG) activation can increase the local intrinsic nerve activity, accelerate sinus rate, and change the earliest activation sites.

METHODS

High-density mapping of the epicardial surface of the right atrium including the SAN was performed in 6 dogs during stimulation of the RSG and after RSG stellectomy. A radio transmitter was implanted into 3 additional dogs to record RSG and local nerve activity at the SAN.

RESULTS

Heart rate accelerated from 108±4 bpm at baseline to 125±7 bpm after RSG stimulation (P=0.001), and to 132±7 bpm after apamin injection (P<0.001). Both electrical RSG stimulation and apamin injection induced local nerve activity at the SAN with the average amplitudes of 3.60±0.72 and 3.86±0.56 μV, respectively. RSG stellectomy eliminated the local nerve activity and decreased the heart rate. In ambulatory dogs, local nerve activity at the SAN had a significantly higher average Pearson correlation to heart rate (0.72±0.02, P=0.001) than RSG nerve activity to HR (0.45±0.04, P=0.001).

CONCLUSIONS

Local intrinsic nerve activity can be recorded at the SAN. Short bursts of these local nerve activities are present before each atrial activation during heart rate acceleration induced by stimulation of the RSG.

Downregulation of M Current Is Coupled to Membrane Excitability in Sympathetic Neurons Before the Onset of Hypertension

Supplemental Digital Content is available in the text.

Neurohumoral activation is an early hallmark of cardiovascular disease and contributes to the etiology of the pathophysiology. Stellectomy has reemerged as a positive therapeutic intervention to modify the progression of dysautonomia, although the biophysical properties underpinning abnormal activity of this ganglia are not fully understood in the initial stages of the disease. We investigated whether stellate ganglia neurons from prehypertensive SHRs (spontaneously hypertensive rats) are hyperactive and describe their electrophysiological phenotype guided by single-cell RNA sequencing, molecular biology, and perforated patch clamp to uncover the mechanism of abnormal excitability. We demonstrate the contribution of a plethora of ion channels, in particular inhibition of M current to stellate ganglia neuronal firing, and confirm the conservation of expression of key ion channel transcripts in human stellate ganglia. We show that hyperexcitability was curbed by M-current activators, nonselective sodium current blockers, or inhibition of Na_v1.1-1.3, Na_v1.6, or I_NaP. We conclude that reduced activity of M current contributes significantly to abnormal firing of stellate neurons, which, in part, contributes to the hyperexcitability from rats that have a predisposition to hypertension. Targeting these channels could provide a therapeutic opportunity to minimize the consequences of excessive sympathetic activation.

Effects of ticagrelor pretreatment on electrophysiological properties of stellate ganglion neurons following myocardial infarction

Higher sympathetic activity predisposes to malignant ventricular arrhythmias in the context of myocardial infarction (MI). This is, in part, mediated by the electrical activity of the stellate ganglion (SG). The aim of this study is to examine the effects of ticagrelor pretreatment on the electrophysiological properties of SG neurons following MI in rabbits. MI was induced by isoproterenol (ISO) of 150 mg kg^-1 d^-1 (twice at an interval of 24 hours). Ticagrelor pretreatment was administered at low- (10 mg kg^-1 d^-1) or high-dose (20 mg kg^-1 d^-1). Protein and RNA expression were determined by immunohistochemical analysis and real-time PCR, respectively. The activity of sodium channel current (I_Na), delayed rectifier potassium current (I_KDR), M-type potassium current (I_KM) as well as action potentials (APs) from SG neurons were measured by whole-cell patch-clamp. Intracellular calcium concentrations were measured by confocal microscopy. Compared with the control group, the MI group exhibited a greater amplitude of I_Na, I_KDR and I_KM, significantly altered activation and inactivation characteristics of I_Na, no significant alterations in protein or mRNA expression of sodium and M-type potassium channels, along with higher AP amplitude and frequency and intracellular calcium concentrations. Most of these abnormalities were prevented by pretreatment with low- or high-dose ticagrelor. Our data suggest that ticagrelor exerts cardioprotective effects, potentially through modulating the activity of different ion channels in SG neurons.

Silent stellate ganglion paraganglioma masquerading as schwannoma: A surgical nightmare

A 28-year-old normotensive female presented with Horner's syndrome and paresthesia over the left side of the chest. Imaging study showed a large heterogeneous enhancing lesion in short-T1 inversion recovery sequence with flow voids in T2W sequence of magnetic resonance imaging. The lesion was located in the left-sided D1 and D2 regions extending into the neural foramina and apical part of the lung. During surgery, even minimal dissection of the tumor resulted in marked fluctuation in hemodynamic parameters, requiring temporary suspension of the surgery multiple times until hemodynamic parameters were brought under control by the anesthesiologist with drugs. The massive fluctuation in hemodynamic parameters in an unprepared and unanticipated scenario was a challenge for the anesthetist and surgeon. The tumor was radically excised with improvement of paresthesia in the immediate postoperative period, but Horner's syndrome persisted. After 18-months of follow–up, she was relieved of all symptoms including Horner's syndrome. Histopathological examination confirmed our suspicion as paraganglioma.

Recurrent ventricular tachycardia after cardiac sympathetic denervation: Prolonged cycle length with improved hemodynamic tolerance and ablation outcomes

INTRODUCTION

Cardiac sympathetic denervation (CSD) is utilized for the management of ventricular tachycardia (VT) in structural heart disease when refractory to radiofrequency ablation (RFA) or when patient/VT characteristics are not conducive to RFA.

METHODS

We studied consecutive patients who underwent CSD at our institution from 2009 to 2018 with VT requiring repeat RFA post-CSD. Patient demographics, VT/procedural characteristics, and outcomes were assessed.

RESULTS

Ninety-six patients had CSD, 16 patients underwent RFA for VT post-CSD. There were 15 male and 1 female patients with mean age of 54.2 ± 13.2 years. Fourteen patients had nonischemic cardiomyopathy. A mean of 2.0 ± 0.8 RFAs for VT was unsuccessful before the patient undergoing CSD. The median time between CSD and RFA was 104 days (interquartile range [IQR] = 15-241). The clinical VT cycle length was significantly increased after CSD both spontaneously on ECG and/or ICD interrogation (355 ± 73 ms pre-CSD vs. 422 ± 94 ms post-CSD, p = .001) and intraprocedurally (406 ± 86 ms pre-CSD vs. 457 ± 88 ms post-CSD, p = .03). Two patients had polymorphic and 14 had monomorphic VT (MMVT) pre-CSD, and all patients had MMVT post-CSD. The proportion of mappable, hemodynamically stable VTs increased from 35% during pre-CSD RFA to 58% during post-CSD RFA (p = .038). At median follow-up of 413 days (IQR = 43-1840) after RFA, eight patients had no further VT.

CONCLUSION

RFA for recurrent MMVT post-CSD is a reasonable treatment option with intermediate-term clinical success in 50% of patients. Clinical VT cycle length was significantly increased after CSD with associated improvement in mappable, hemodynamically tolerated VT during RFA.

Left stellate ganglion block, a rescue treatment for ventricular arrhythmia refractory to radiofrequency catheter ablation: A care-compliant case report

RATIONALE

Stellate Ganglion Block (SGB) provides a blockade of sympathetic signals from the sympathetic chain and appears to be a promising method of controlling refractory ventricular arrhythmias, but there are scanty data in the literature.

PATIENT CONCERNS

Herein, we describe a 59-year-old male patient with a history of non-ischemic cardiomyopathy and suffering from frequent VT episodes, who received ICD implantation and regular amiodarone medication control.

DIAGNOSES

Monomorphic VT refractory to standard medication control and focal extensive catheter ablation.

INTERVENTIONS

Left Stellate Ganglion Block (LSGB) was performed under ultrasound-assisted injection at the C6 level using a 10 ml solution of 0.4% lidocaine and 0.5% bupivacaine.

OUTCOMES

In our case, refractory VT subsided and sinus rhythm was retained immediately after LSGB. There were no VT episodes for at least 3 hours during the inter-hospital transfer, which did not involve any specific complications.

LESSONS

LSGB may provide effective VT control and play an important role in rescue and bridge therapy before catheter ablation.

The "question-mark" MR anatomy of the cervico-thoracic ganglia complex: can it help to avoid mistaking it for a malignant lesion on 68Ga-PSMA-11 PET/MR?

Background

Detectable uptake of ⁶⁸Ga-PSMA-ligands in sympathetic ganglia may potentially lead to mistaking them for malignant lesions. Our aim was to investigate the anatomy of cervico-thoracic-ganglia-complex (CTG-C) in the MR part of multimodal ⁶⁸Ga-PSMA-11 PET/MR imaging, in view of PET factors hindering its proper identification.

Patients and methods

In 106 patients, 212 sites of the CTG-C were retrospectively reviewed to assess the radiotracer uptake (SUV_max), size, shape, position, symmetry of location and visual uptake intensity. Asymmetry of PSMA-ligand uptake and increased uptake were regarded as risk factors of malignancy.

Results

In 66.0% left (L) and 53.8% right (R) CTG-C we noticed configurations, resembling the shape of an exclamation-mark, a question-mark, or its part (called “typical”). Tumor-like CTG-C shapes (oval, binodular or longitudinal) were detected in 28.3% L-CTG-C and in 40.6% R-CTG-C. When visual assessment of PET suggested malignancy, the recognition of “typical” shape of underlying CTG-C on MR generated a rise in the accuracy of their proper identification (from 34.4% to 75%, χ2(1) = 70.4; p < 0.001). Recognizing the shape of the CTG-C as “typical” in MR allowed us to classify as “not-suspicious” 61.9% of all CTG-C which were treated as “suspicious” after sole PET assessment.

Conclusions

The characteristic shape of cervico-thoracic-ganglia-complex (resembling a question-mark, or its part) helps in proper recognition of CTG-C on multimodal whole-body ⁶⁸Ga-PSMA-ligand PET/MR imaging, when detectable uptake might lead to considering pathology.

Neuromodulation for Ventricular Tachycardia and Atrial Fibrillation: A Clinical Scenario-Based Review

Autonomic dysregulation in cardiovascular disease plays a major role in the pathogenesis of arrhythmias. Cardiac neural control relies on complex feedback loops consisting of efferent and afferent limbs, which carry sympathetic and parasympathetic signals from the brain to the heart and sensory signals from the heart to the brain. Cardiac disease leads to neural remodeling and sympathovagal imbalances with arrhythmogenic effects. Preclinical studies of modulation at central and peripheral levels of the cardiac autonomic nervous system have yielded promising results, leading to early stage clinical studies of these techniques in atrial fibrillation and refractory ventricular arrhythmias, particularly in patients with inherited primary arrhythmia syndromes and structural heart disease. However, significant knowledge gaps in basic cardiac neurophysiology limit the success of these neuromodulatory therapies. This review discusses the recent advances in neuromodulation for cardiac arrhythmia management, with a clinical scenario-based approach aimed at bringing neurocardiology closer to the realm of the clinical electrophysiologist.

Alleviation of Dyspnea Sensation by Phototherapy in Healthy Adults

BACKGROUND

Because both dyspnea and pain have common features from a clinical and physiologic point of view, we hypothesized that stellate ganglion irradiation by using a linear polarized near-infrared ray device, which is often used for pain management, might be applicable for dyspnea relief. To evaluate the use of stellate ganglion irradiation as a novel noninvasive treatment for dyspnea, we investigated the influence of stellate ganglion irradiation on dyspnea.

METHODS

Perceptions of dyspnea were examined with or without stellate ganglion irradiation in 28 healthy adults. The sensation of breathing difficulty was induced by a two-way non-rebreathing valves with linear inspiratory resistance (R) of 0, 10, 20, and 30 cm H₂O/L/s. Dyspnea was evaluated with the modified Borg scale to determine subjects' discomfort level. Stellate ganglion irradiation was performed by intermittent irradiation near the bilateral stellate ganglion by using a linear polarized near-infrared ray device.

RESULTS

There were significant changes from baseline at R = 10 cm H₂O/L/s (P = .007), R = 20 cm H₂O/L/s (P = .005), and R = 30 cm H₂O/L/s (P = .009). For each resistive load, the mean dyspnea sensation score was lower with stellate ganglion irradiation compared with sham irradiation, with significant differences (P = .003 at R = 0 cm H₂O/L/s; P < .001 at R = 10, 20, 30 cm H₂O/L/s). There was a significantly lower slope of the dyspnea response for the linear regression of the loads and Borg scores in the stellate ganglion irradiation versus sham treatment (P = .003).

CONCLUSIONS

Stellate ganglion irradiation significantly alleviated dyspnea induced by an external inspiratory load in healthy adults. Stellate ganglion irradiation might be an option to treat dyspnea in some cases. Further studies in individuals with diverse types of dyspnea and clinical settings are warranted.

Complications associated with stellate ganglion nerve block: a systematic review

Stellate ganglion nerve blockade (SGNB) is a vital tool in our armamentarium for the treatment of various chronic pain syndromes. SGNB can be performed using the traditional landmark-based approach, or with image guidance using either fluoroscopy or ultrasound. In this review, we systematically analyzed reported SGNB-related complications between 1990 and 2018. Seven databases were queried for SGNB between January 1, 1990 and November 27, 2018. Search results of the complications associated with SGNB were reported as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. Out of a total of 1909 articles, 67 articles met our inclusion criteria, yielding 260 cases with adverse events. In 134 of the 260 (51.5%) cases, SGNB was performed with image guidance. Sixty-four (24.6%) and 70 (26.9%) of the complication cases reported the use of ultrasound and fluoroscopy guidance, respectively. One hundred and seventy-eight (68.4%) patients had medication-related or systemic side effects, and 82 (31.5%) had procedure-related or local side effects. There was one report of death due to massive hematoma leading to airway obstruction. There was one case report of quadriplegia secondary to pyogenic cervical epidural abscess and discitis following an SGNB. Complications following SGNB have been reported with both landmark-based techniques and with imaging guidance using fluoroscopy or ultrasound. In our systematic review, most adverse events that were reported occurred during or shortly after SGNB. Vigilance, American Society of Anesthesiologists standard monitors for conscious sedation, and accessibility to resuscitation equipment are vital to the safe performance of SGNB.

CT-Guided Stellate Ganglion Pulsed Radiofrequency Stimulation for Facial and Upper Limb Postherpetic Neuralgia

Objective: Postherpetic neuralgia (PHN) is the most common complication of herpes zoster, manifesting as a persistent, spontaneous, knife-like pain or paroxysmal burning that seriously affects a patient’s quality of life. An effective treatment of PHN is lacking. This retrospective study examined the efficacy and safety of stellate ganglion (SG) pulsed radiofrequency (PRF) on facial and upper limb PHN.

Methods: Eighty-four patients with PHN on the face or upper limbs were enrolled for the study. Patients were randomly divided into two surgical groups according to the order of enrollment; one group underwent SG block (SG-B group, n = 42) and the other underwent SG pulsed radiofrequency (SG-P group, n = 42). After surgery, patients were followed at 1 week, 2 weeks, 1 month, 3 months, and 6 months. Observation at each follow-up included basic patient characteristics, visual analog scale (VAS), quality of life (QOL) using Physical Component Summary (PCS), and Mental Component Summary (MCS) to assess, total effective rate, complications and side effects.

Results: Compared with preoperative values, VAS decreased in both groups after surgery (P < 0.05). In the SG-B group, VAS increased after 1 month, while in the SG-P group, VAS gradually decreased at later follow-up time points. VAS decreased more significantly in the SG-P group after 1 month (P < 0.05). PCS and MCS increased in both groups after the operation, and the difference was significant compared with preoperative values (P < 0.05). The total effective rates of the SG-B and SG-P groups were 64.3 and 83.3%, respectively. The total effective rate of the SG-P group was higher than that of the SG-B group (P < 0.05). The incidence of complications and side effects in the SG-B group was higher than that in the SG-P group (P < 0.05).

Conclusion: SG pulsed radiofrequency treatment of facial and upper limb PHN is safe and effective. It is a treatment method worth promoting.

Clinical effects of pulsed radiofrequency to the thoracic sympathetic ganglion versus the cervical sympathetic chain in patients with upper-extremity complex regional pain syndrome: A retrospective analysis

Pulsed radiofrequency (PRF) to the thoracic sympathetic ganglion (TSG PRF) or to the cervical sympathetic chain (CSC PRF) can be performed to overcome transient effects of single sympathetic blocks in patients with upper-extremity complex regional pain syndrome (CRPS).We retrospectively compared the clinical effects of TSG PRF and CSC PRF. Seven TSG PRF cases and 10 CSC PRF cases were enrolled in the present analysis. We assessed effectiveness with multiple clinical measurements: a numerical rating scale (NRS) of pain before and 1 week after the procedure, postprocedure temperature, effect duration, and a self-described patient satisfaction score.The temperature was significantly higher in TSG PRF cases than in CSC PRF cases. Pain values (according to the NRS) 1 week after the procedure were significantly lower, and the effect duration was significantly longer, after TSG PRF than after CSC PRF.TSG PRF is a more effective procedure than CSC PRF for managing chronic upper-extremity CRPS.

Change of Tinnitus with Xenon Phototherapy of the Stellate Ganglion

OBJECTIVE

To develop a treatment for tinnitus called xenon phototherapy of the stellate ganglion (XPSG) and analyze its effect on tinnitus.

METHODS

Patients with chronic tinnitus received XPSG. Symptoms were assessed subjectively with tinnitus handicap inventory (THI) and numerical rating scale (NRS). THI and NRS scores were analyzed in XPSG (n = 43) and sham treatment (non-XPSG) (n = 18) groups.

RESULTS

THI and NRS scores improved significantly after 3 months of XPSG. Severe cases with high THI or NRS score showed greater improvement. No significant difference was observed between before and after sham treatment in non-XPSG groups.

CONCLUSIONS

XPSG significantly improved THI and NRS scores with high patient satisfaction.

Effects of Vagal Nerve Stimulation on Ganglionated Plexi Nerve Activity and Ventricular Rate in Ambulatory Dogs With Persistent Atrial Fibrillation

OBJECTIVES

This study was designed to test the hypothesis that low-level vagal nerve stimulation (VNS) reduces the ventricular rate (VR) during atrial fibrillation (AF) through the activation of the inferior vena cava (IVC)-inferior atrial ganglionated plexus nerve activity (IAGPNA).

BACKGROUND

Increased IVC-IAGPNA can suppress atrioventricular node conduction and slow VR in canine models of AF.

METHODS

Persistent AF was induced in 6 dogs and the IVC-IAGPNA, right vagal nerve activity, left vagal nerve activity, and an electrocardiogram were recorded. After persistent AF was documented, VNS was programed to 14 s "on" and 1.1 min "off." After 1 week, the VNS was reprogramed to 3 min off and stimulation continued for another week. Neural remodeling of the stellate ganglion (SG) was assessed with tyrosine hydroxylase staining and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling staining.

RESULTS

Average IVC-IAGPNA was increased during both VNS 1.1 min off (8.20 ± 2.25 μV [95% confidence interval (CI): 6.33 to 9.53 μV]; p = 0.002) and 3 min off (7.96 ± 2.03 μV [95% CI: 6.30 to 9.27 μV]; p = 0.001) versus baseline (7.14 ± 2.20 μV [95% CI: 5.35 to 8.52 μV]). VR was reduced during both VNS 1.1 min off (123.29 ± 6.29 beats/min [95% CI: 116.69 to 129.89 beats/min]; p = 0.001) and 3 min off (120.01 ± 4.93 beats/min [95% CI: 114.84 to 125.18 beats/min]; p = 0.001) compared to baseline (142.04 ± 7.93 bpm [95% CI: 133.72 to 150.37]). Abnormal regions were observed in the left SG, but not in the right SG. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling-positive neurons were found in 22.2 ± 17.2% [95% CI: 0.9% to 43.5%] of left SG cells and 12.8 ± 8.4% [95% CI: 2.4% to 23.2%] of right SG cells.

CONCLUSIONS

Chronic low-level VNS increases IVC-IAGPNA and damages bilateral stellate ganglia. Both mechanisms could contribute to the underlying mechanism of VR control during AF.

Neurotransmitter Switching Coupled to β-Adrenergic Signaling in Sympathetic Neurons in Prehypertensive States

Single or combinatorial administration of β-blockers is a mainstay treatment strategy for conditions caused by sympathetic overactivity. Conventional wisdom suggests that the main beneficial effect of β-blockers includes resensitization and restoration of β1-adrenergic signaling pathways in the myocardium, improvements in cardiomyocyte contractility, and reversal of ventricular sensitization. However, emerging evidence indicates that another beneficial effect of β-blockers in disease may reside in sympathetic neurons. We investigated whether β-adrenoceptors are present on postganglionic sympathetic neurons and facilitate neurotransmission in a feed-forward manner. Using a combination of immunocytochemistry, RNA sequencing, Förster resonance energy transfer, and intracellular Ca2+ imaging, we demonstrate the presence of β-adrenoceptors on presynaptic sympathetic neurons in both human and rat stellate ganglia. In diseased neurons from the prehypertensive rat, there was enhanced β-adrenoceptor-mediated signaling predominantly via β2-adrenoceptor activation. Moreover, in human and rat neurons, we identified the presence of the epinephrine-synthesizing enzyme PNMT (phenylethanolamine-N-methyltransferase). Using high-pressure liquid chromatography with electrochemical detection, we measured greater epinephrine content and evoked release from the prehypertensive rat cardiac-stellate ganglia. We conclude that neurotransmitter switching resulting in enhanced epinephrine release, may provide presynaptic positive feedback on β-adrenoceptors to promote further release, that leads to greater postsynaptic excitability in disease, before increases in arterial blood pressure. Targeting neuronal β-adrenoceptor downstream signaling could provide therapeutic opportunity to minimize end-organ damage caused by sympathetic overactivity.

[Catgut implantation at stellate ganglion for postmenopausal osteoporosis]

OBJECTIVE

To compare the efficacy differences between catgut implantation at stellate ganglion combined with oral administration of alendronate sodium and oral administration of alendronate sodium alone on postmenopausal osteoporosis (PO).

METHODS

Sixty patients of PO were randomly divided into an observation group and a control group, 30 cases in each one. The patients in the control group were treated with oral administration of alendronate sodium. Based on the treatment of control group, the patients in the observation group were treated with catgut implantation at stellate ganglion. The treatment was given once a week in the two groups; the consecution treatment of four weeks constituted one session, and totally six sessions were given. The changes of total syndrome score, bone mineral density of lumbar vertebra (L₁ to L₄) and femeral neck (FN) and estradiol were observed before and after treatment; the clinical efficacy was compared between the two groups.

RESULTS

Compared before treatment, the total syndrome score, bone mineral density of lumbar vertebra (L₁ to L₄) and FN and estradiol were significantly improved after treatment (all P<0.05); which were more significant in the observation group (all P<0.05). Compared before treatment, the level of estradiol in the control group was not significantly changed after treatment (P>0.05), while that in the observation group was significantly changed after treatment (P<0.05). After treatment, the level of estradiol in the observation group was higher than that in the control group (P<0.05). The total effective rate was 93.3% (28/30) in the observation group, which was significantly higher than 83.3% (25/30) in the control group (P<0.05).

CONCLUSION

Catgut implantation at stellate ganglion combined with oral administration of alendronate sodium are superior to oral administration of alendronate sodium alone for postmenopausal osteoporosis, which improve the clinical symptoms, regulate the hormone level and increase bone mineral density.

Effects of Stellate Ganglion Cryoablation on Subcutaneous Nerve Activity and Atrial Tachyarrhythmias in a Canine Model of Pacing-Induced Heart Failure

OBJECTIVES

This study aimed to test the hypothesis that subcutaneous nerve activity (SCNA) can adequately estimate the cardiac sympathetic tone and the effects of cryoablation of the stellate ganglion in dogs with pacing-induced heart failure (HF).

BACKGROUND

Recording of SCNA is a new method to estimate sympathetic tone in dogs. HF is known to increase sympathetic tone and atrial arrhythmias.

METHODS

Twelve dogs with pacing-induced HF were studied using implanted radiotransmitters to record the stellate ganglia nerve activity (SGNA), vagal nerve activity, and SCNA. Of these, 6 dogs (ablation group) underwent bilateral stellate ganglia cryoablation before the rapid ventricular pacing; the remaining 6 dogs (control group) had rapid ventricular pacing only. In both groups, SCNA was compared with SGNA and the occurrence of arrhythmias.

RESULTS

SCNA invariably increased before the 360 identified atrial tachyarrhythmia episodes in the 6 control dogs before and after HF induction. SCNA and SGNA correlated in all dogs with an average correlation coefficient of 0.64 (95% confidence interval: 0.58 to 0.70). Cryoablation of bilateral stellate ganglia significantly reduced SCNA from 0.34 ± 0.033 μV to 0.25 ± 0.028 μV (p = 0.03) and eliminated all atrial tachyarrhythmias.

CONCLUSIONS

SCNA can be used to estimate cardiac sympathetic tone in dogs with pacing-induced HF. Cryoablation of the stellate ganglia reduced SCNA and arrhythmia vulnerability.

Ultrasound-guided Stellate Ganglion Block Improves Gastrointestinal Function After Thoracolumbar Spinal Surgery

PURPOSE

The purpose of this study was to investigate the effects of stellate ganglion block (SGB) on gastrointestinal function after thoracolumbar spinal surgery.

METHODS

Forty patients with thoracolumbar fracture scheduled for posterior spinal surgery were randomly assigned to 2 groups: ultrasound-guided SGB or sham (control group). After induction, ultrasound-guided SGB (n = 20) or a sham procedure (n = 20) was conducted with a 6-mL injection of 1% lidocaine or 0.9% saline, respectively. Primary outcomes were postoperative gastrointestinal function, including auscultation of bowel sounds, incidence and degree of abdominal bloating, flatus time, and paralytic ileus.

FINDINGS

Patients in the SGB group had better gastrointestinal function compared with those in the sham (control) group, as indicated by more regular bowel sounds at 24 and 36 hours postoperatively (80% vs 40%, P = 0.024, and 95% vs 60%, P = 0.023), lesser abdominal bloating (10% vs 45%, P = 0.034), and slightly shorter flatus time (mean [SD], 12.0 [4.4] vs 14.7 [4.6] hours, P = 0.068). Survival analysis based on regular bowel sounds found a significant difference between the 2 groups (P = 0.004). In addition, more patients had higher satisfaction after SGB (85% vs 45%, P = 0.020). No postoperative ileus or mortality occurred.

IMPLICATIONS

In this preliminary study, ultrasound-guided SGB accelerated the return of gastrointestinal transit, alleviated bowel symptoms, and improved patient satisfaction after thoracolumbar spinal surgery. chictr.org.cn identifier: ChiCTR-TRC-14004289.

Ultrasound guided injections of botulinum toxin type A into stellate ganglion to treat insomnia

The aim of the study was to investigate the curative effect of botulinum toxin type A (BTX-A) injection into stellate ganglion under ultrasound guidance in patients suffering from insomnia. From October 2015 to April 2016, 48 patients suffering from insomnia were enrolled in this study. Patients were divided into 2 groups using a random digital grouping method: i) Control group (24 cases), and ii) treatment group (24 cases). Patients in the control group received 1 mg oral estazolam 30 min before sleep every night, while patients in the treatment group received BTX-A injection in bilateral stellate ganglions under ultrasound guidance. Curative effect evaluation was carried out after treatment. The international Pittsburgh Sleep Quality Index (PSQI) and polysomnogram (PSG) were evaluated in the two groups before and after treatment. The total effective rate was obviously higher in the treatment group. The PSQI score and the results of the PSG indicated that the insomnia situation improved in both groups. However, compared with the control group, the treatment group had a more significant improvement. In conclusion, BTX-A injection in stellate ganglion was a relatively easy and effective way to treat insomnia without any notable adverse reactions.

Effects of extrinsic cardiac nerve stimulation on atrial fibrillation inducibility: The regulatory role of the spinal cord

OBJECTIVE

To investigate the effect of the mutual regulation of the extrinsic cardiac nerves on atrial electrophysiology and atrial fibrillation (AF) vulnerability.

METHODS AND RESULTS

Fourteen dogs were randomly divided into two groups: spinal cord stimulation (SCS) group (n = 7) and spinal cord block (SCB) group (n = 7). SCS was performed with 90% of the threshold voltage stimulating the T₁ -T₂ spinal level, while SCB was performed by injecting 2% lidocaine into the epidural space at the T_2-3 level. The effective refractory period (ERP), ERP dispersion, and AF inducibility were measured during atrial pacing combined with different extrinsic cardiac nerve stimulation. ERPs were decreased in the atrium and pulmonary veins and ERP dispersion was increased from baseline during left cervical vagus nerve stimulation (VNS) or left stellate ganglion stimulation (SGS) in the two groups. When combined with SCS, VNS resulted in diminished ERPs at all recording sites, longer ERP dispersion and more episodes of AF than were observed during VNS, whereas ERPs were greater and correspondingly fewer episodes of AF occurred during SCS combined with SGS than SGS. In the SCB group, ERPs were shortened, ERP dispersion was lengthened, and episodes of AF were increased during SGS after SCB. SCS enhanced the activity of the left vagus nerve but attenuated the left stellate ganglion and superior left ganglionated plexus.

CONCLUSION

SCS modulates extrinsic and intrinsic cardiac nerve activity among the vagus nerve, stellate ganglion, and ganglionated plexus. SCS facilitates the effect of VNS and attenuates the effect of SGS on atrial electrophysiology.

Overexpression of Sarcoendoplasmic Reticulum Calcium ATPase 2a Promotes Cardiac Sympathetic Neurotransmission via Abnormal Endoplasmic Reticulum and Mitochondria Ca2+ Regulation

Supplemental Digital Content is available in the text.

Reduced cardiomyocyte excitation–contraction coupling and downregulation of the SERCA2a (sarcoendoplasmic reticulum calcium ATPase 2a) is associated with heart failure. This has led to viral transgene upregulation of SERCA2a in cardiomyocytes as a treatment. We hypothesized that SERCA2a gene therapy expressed under a similar promiscuous cytomegalovirus promoter could also affect the cardiac sympathetic neural axis and promote sympathoexcitation. Stellate neurons were isolated from 90 to 120 g male, Sprague–Dawley, Wistar Kyoto, and spontaneously hypertensive rats. Neurons were infected with Ad-mCherry or Ad-mCherry-hATP2Aa (SERCA2a). Intracellular Ca²⁺ changes were measured using fura-2AM in response to KCl, caffeine, thapsigargin, and carbonylcyanide-p-trifluoromethoxyphenylhydrazine to mobilize intracellular Ca²⁺ stores. The effect of SERCA2a on neurotransmitter release was measured using [³H]-norepinephrine overflow from 340 to 360 g Sprague–Dawley rat atria in response to right stellate ganglia stimulation. Upregulation of SERCA2a resulted in greater neurotransmitter release in response to stellate stimulation compared with control (empty: 98.7±20.5 cpm, n=7; SERCA: 186.5±28.41 cpm, n=8; P<0.05). In isolated Sprague–Dawley rat stellate neurons, SERCA2a overexpression facilitated greater depolarization-induced Ca²⁺ transients (empty: 0.64±0.03 au, n=57; SERCA: 0.75±0.03 au, n=68; P<0.05), along with increased endoplasmic reticulum and mitochondria Ca²⁺ load. Similar results were observed in Wistar Kyoto and age-matched spontaneously hypertensive rats, despite no further increase in endoplasmic reticulum load being observed in the spontaneously hypertensive rat (spontaneously hypertensive rats: empty, 0.16±0.04 au, n=18; SERCA: 0.17±0.02 au, n=25). In conclusion, SERCA2a upregulation in cardiac sympathetic neurons resulted in increased neurotransmission and increased Ca²⁺ loading into intracellular stores. Whether the increased Ca²⁺ transient and neurotransmission after SERCA2A overexpression contributes to enhanced sympathoexcitation in heart failure patients remains to be determined.

Central vs. peripheral neuraxial sympathetic control of porcine ventricular electrophysiology

Sympathoexcitation is associated with ventricular arrhythmogenesis. The aim of this study was to determine the role of thoracic dorsal root afferent neural inputs to the spinal cord in modulating ventricular sympathetic control of normal heart electrophysiology. We hypothesize that dorsal root afferent input tonically modulates basal and evoked efferent sympathetic control of the heart. A 56-electrode sock placed on the epicardial ventricle in anesthetized Yorkshire pigs (n = 17) recorded electrophysiological function, as well as activation recovery interval (ARI) and dispersion in ARI, at baseline conditions and during stellate ganglion electrical stimulation. Measures were compared between intact states and sequential unilateral T1-T4 dorsal root transection (DRTx), ipsilateral ventral root transection (VRTx), and contralateral dorsal and ventral root transections (DVRTx). Left or right DRTx decreased global basal ARI [Lt.DRTx: 369 ± 12 to 319 ± 13 ms (P < 0.01) and Rt.DRTx: 388 ± 19 to 356 ± 15 ms (P < 0.01)]. Subsequent unilateral VRTx followed by contralateral DRx+VRTx induced no further change. In intact states, left and right stellate ganglion stimulation shortened ARIs (6 ± 2% vs. 17 ± 3%), while increasing dispersion (+139% vs. +88%). There was no difference in magnitude of ARI or dispersion change with stellate stimulation following spinal root transections. Interruption of thoracic spinal afferent signaling results in enhanced basal cardiac sympathoexcitability without diminishing the sympathetic response to stellate ganglion stimulation. This suggests spinal dorsal root transection releases spinal cord-mediated tonic inhibitory control of efferent sympathetic tone, while maintaining intrathoracic cardiocentric neural networks.

Effects of Intrinsic and Extrinsic Cardiac Nerves on Atrial Arrhythmia in Experimental Pulmonary Artery Hypertension

Atrial arrhythmia, which includes atrial fibrillation (AF) and atrial flutter (AFL), is common in patients with pulmonary arterial hypertension (PAH), who often have increased sympathetic nerve activity. Here, we tested the hypothesis that autonomic nerves play important roles in vulnerability to AF/AFL in PAH. The atrial effective refractory period and AF/AFL inducibility at baseline and after anterior right ganglionated plexi ablation were determined during left stellate ganglion stimulation or left renal sympathetic nerve stimulation in beagle dogs with or without PAH. Then, sympathetic nerve, β-adrenergic receptor densities and connexin 43 expression in atrial tissues were assessed. The sum of the window of vulnerability to AF/AFL was increased in the right atrium compared with the left atrium at baseline in the PAH dogs but not in the controls. The atrial effective refractory period dispersion was increased in the control dogs, but not in the PAH dogs, during left stellate ganglion stimulation. The voltage thresholds for inducing AF/AFL during anterior right ganglionated plexi stimulation were lower in the PAH dogs than in the controls. The AF/AFL inducibility was suppressed after ablation of the anterior right ganglionated plexi in the PAH dogs. The PAH dogs had higher sympathetic nerve and β1-adrenergic receptor densities, increased levels of nonphosphorylated connexin 43, and heterogeneous connexin 43 expression in the right atrium when compared with the control dogs. The anterior right ganglionated plexi play important roles in the induction of AF/AFL. AF/AFL induction was associated with right atrium substrate remodeling in dogs with PAH.

Impacts of stellate ganglion block on plasma NF-κB and inflammatory factors of TBI patients

The aim of this study was to initially explore the regulatory mechanism of brain function protection of SGB from the view of nerve-endocrine-immune network. 50 patients with traumatic brain injury (TBI) were divided into the SGB treatment group and the control group, the changes of serum IL-6, IL-1β, TNF-α and CGRP levels were detected by ELISA, and the changes of lymphocyte NF-κB protein expression was detected by Western Blot. The control group exhibited the higher expression of IL-6, IL-1β and TNF-α, while the SGB treatment group exhibited various degrees of reduction. On the second day of TBI, the CGRP expression was significantly increased, which was much more significant in the SGB group, and the duration was much longer. The control group exhibited the increased NF-κB p65 and NF-κB p50 after TBI; after the SGB treatment, the NF-κB p65 protein level was significantly reduced, while the NF-κB p50 protein level would not be significantly changed. SGB could chronergically inhibit the excessive inflammatory response in the early post-TBI stage, which suggested that SGB might be involved into the regulation of post-TBI nerve-endocrine-immune system dysfunction.

Augmentation of cardiac sympathetic tone by percutaneous low-level stellate ganglion stimulation in humans: a feasibility study

Modulation of human cardiac mechanical and electrophysiologic function by direct stellate ganglion stimulation has not been performed. Our aim was to assess the effect of low-level left stellate ganglion (LSG) stimulation (SGS) on arrhythmias, hemodynamic, and cardiac electrophysiological indices. Patients undergoing ablation procedures for arrhythmias were recruited for SGS. A stimulating electrode was placed next to the LSG under fluoroscopy and ultrasound imaging; and SGS (5-10 Hz, 10-20 mA) was performed. We measured hemodynamic, intracardiac and ECG parameters, and activation recovery intervals (ARIs) (surrogate for action potential duration) from a duodecapolar catheter in the right ventricular outflow tract. Five patients underwent SGS (3 males, 45 ± 20 years). Stimulating catheter placement was successful, and without complication in all patients. SGS did not change heart rate, but increased mean arterial blood pressure (78 ± 3 mmHg to 98 ± 5 mmHg, P < 0.001) and dP/dt max (1148 ± 244 mmHg/sec to 1645 ± 493 mmHg/sec, P = 0.03). SGS shortened mean ARI from 304 ± 23 msec to 283 ± 17 msec (P < 0.001), although one patient required parasympathetic blockade. Dispersion of repolarization (DOR) increased in four patients and decreased in one, consistent with animal models. QT interval, T-wave duration and amplitude at baseline and with SGS were 415 ± 15 msec versus 399 ± 15 msec (P < 0.001); 201 ± 12 msec versus 230 ± 28 msec; and 0.2 ± 0.09 mV versus 0.22 ± 0.08 mV, respectively. At the level of SGS performed, no increase in arrhythmias was seen. Percutaneous low-level SGS shortens ARI in the RVOT, and increases blood pressure and LV contractility. These observations demonstrate feasibility of percutaneous SGS in humans.

Stellate Ganglion Block for the Treatment of Hot Flashes in Patients with Breast Cancer: A Literature Review

BACKGROUND

Currently, hormone replacement therapy (HRT) is the only US Food and Drug Administration-approved treatment for hot flashes, resulting in clinical improvement in 80%-90% of symptomatic women. However, HRT is not recommended for patients with breast cancer. Current data regarding the use of stellate ganglion block (SGB) for the treatment of vasomotor symptoms in symptomatic women with a diagnosis of breast cancer are promising.

METHODS

A PubMed search for recent articles on the effects of SGB for the treatment of hot flashes in patients with breast cancer identified 11 articles published between 2005-2014.

RESULTS

Five articles described the physiology of hot flashes and the hypothesis of why SGB would be a treatment option, and 6 were clinical articles.

CONCLUSION

The available results of SGB efficacy are promising but demonstrate significant variability. A large prospective randomized controlled trial is required to determine the exact success of SGB on hot flashes and quality of life in breast cancer survivors.

Low dose high frequency ultrasound therapy for stellate ganglion blockade in complex regional pain syndrome type I: a randomised placebo controlled trial

BACKGROUND

We aimed to determine the sympatholytic and clinical effects of low dose high frequency ultrasound (US) applied on stellate ganglion in Complex Regional Pain Syndrome (CRPS) type I patients.

MATERIAL AND METHOD

Fourty-five patients with CRPS type I were randomly allocated into three groups. Pharmacological treatment, transcutaneous electrical nerve stimulation (TENS), contrast bath and exercise were applied to all groups for 20 sessions. In addition to this treatment protocol, low dose high frequency US was applied on stellate ganglion as 0.5 watts/cm(2) in group I; 3 watts/cm(2) in group II and as placebo in group III. Forty age and sex matched healthy controls were served as controls. Sympathetic skin response (SSR) was used for determining the sympatholytic effects of US. Pain was assessed with visual analog scale (VAS), limitation of total finger flexion was assessed with finger pulp-distal crease distance, muscle strength was assessed with measuring the grip strength, upper extremity disability was assessed with Disability of the Arm, Shoulder and Hand (DASH) scale before and after the treatment.

RESULTS

All groups evalueted in terms of VAS score, finger pulp-distal crease distance, grip strength and DASH score after the treatment. The improvements in those parameters were not statistically significant between the groups (P > 0.05). SSR latency was significantly shorter in CRPS patients than controls (P < 0.05). Pre- and post-treatment SSR amplitude and latency values were not different within patient groups (P > 0.05). The differences in pre- and post-treatment SSR amplitude and latency values were not statistically different between patient groups (P > 0.05).

CONCLUSION

Low dose high frequency US applied on stellate ganglion did not make a sympathetic blockade and was not of further benefit for pain, range of motion, grip strength and upper extremity disability in CRPS type I patients.

Radiofrequency ablation of stellate ganglion in a patient with complex regional pain syndrome

Complex regional pain syndrome (CRPS) is characterized by a combination of sensory, motor, vasomotor, pseudomotor dysfunctions and trophic signs. We describe the use of radiofrequency (RF) ablation of Stellate ganglion (SG) under fluoroscopy, for long-term suppression of sympathetic nervous system, in a patient having CRPS-not otherwise specified. Although the effects of thermal RF neurolysis may be partial or temporary, they may promote better conditions toward rehabilitation. The beneficial effect obtained by the RF neurolysis of SG in this particular patient strongly advocates the use of this mode of therapy in patients with CRPS.