A Case Report on USG-Guided Stellate Ganglion Block in Refractory Ventricular Tachycardia

ABSTRACT

Pain doctors and anesthesiologists often execute stellate ganglion blocks to treat excruciating upper extremity sympathetic pain disorders. Given the ganglion’s near proximity to important vascular and neurological systems, considerable care and understanding are required. This method has been successfully used to intractable ventricular tachyarrhythmias, according to recent research. This case report describes how we were able to successfully ablate intractable ventricular tachycardia that was resistant to medical treatment, including repeated shocks, using ultrasound-guided stellate ganglion block. For refractory ventricular tachyarrhythmias, stellate ganglion block may be an effective and accessible bedside therapy option if its sonographic anatomy is well understood.

INTRODUCTION

These days, one of the most popular sympathetic blocks carried out is the stellate ganglion block (SGB). Vascular, visceral, and neuropathic pain are all significantly influenced by the sympathetic nervous system. Consequently, a wide range of medical disorders, both painful and non-painful, may benefit from the SGB. Long QT syndrome may be treated with left stellate, which efficiently inhibits the cardioaccelerator fibers. QT and QTc intervals are significantly reduced after a successful SGB.[1] Percutaneous stellate ganglion blockade is a viable and potentially life-saving treatment for patients with severe ventricular arrhythmias or ablation-refractory conditions who might not be candidates for surgical stellate ganglion blockade.[2] Although there are a few case reports in the literature, the regular use of left SGB as a therapeutic technique in the acute phase of refractory ventricular arrhythmia has not yet been established as a therapy regimen. Here, we provide evidence to support the convenience and security of SGB as a bedside treatment for refractory ventricular tachycardia.

CASE REPORT

A 58-year-old female patient was admitted to the emergency department with complaints of severe upper abdominal pain persisting for one week. The patient had a documented history of coronary artery disease accompanied by dilated cardiomyopathy, with a prior echocardiography report indicating a left ventricular ejection fraction (LVEF) of 35%. The patient received symptomatic treatment, and the abdominal ultrasound indicated features consistent with cholelithiasis. Routine preparation and evaluation regarding cholelithiasis was commenced. Potassium level in serum was measured at 2.9 mmol/L. Rest investigations yielded normal results. On the second day of admission, the patient experienced recurrent paroxysmal supraventricular tachycardia (PSVT). Two-dimensional echocardiography revealed a jerky septum accompanied by frequent ectopic beats throughout the examination. Left ventricular ejection fraction (LVEF) is 50%, with trace tricuspid regurgitation and grade 1 left ventricular dysfunction. The patient was transferred to the cardiac care unit for additional evaluation and management. Holter monitoring was conducted, resulting in a total recording duration of 24 hours and 12 minutes. The baseline rhythm exhibited sinus characteristics with intraventricular conduction delay, presenting an average heart rate of 71 bpm, a minimum heart rate of 49 bpm, and a maximum heart rate of 156 bpm. The patient experienced recurrent episodes of paroxysmal supraventricular tachycardia that did not respond to optimal medical treatment. On the fourth day, she underwent an electrophysiology study and radiofrequency ablation, during which the aberrant pathway was ablated. On the ninth day, the patient developed recurrent ventricular tachycardia that did not respond to medical management. Serum magnesium levels were measured at 2 mg/dl. She experienced several shocks of 200 joules, which only provided a temporary cessation of the ventricular tachycardia. Repeat echocardiography indicated a jerky septum with a left ventricular ejection fraction (LVEF) of 35%. The patient experienced ongoing episodes of ventricular tachycardia despite pharmacological intervention. On the 12^th day, following multiple episodes of ventricular tachycardia, she received an ultrasound-guided left stellate ganglion block using 5 ml of 1% lignocaine as a short-acting local anesthetic. No repeat episodes of VT occurred in the subsequent 24 hours; therefore, the procedure was repeated using a long-acting local anesthetic, specifically 10 ml of 0.2% ropivacaine. The successful blocks resulted in ipsilateral Horner’s syndrome, characterized by ptosis, miosis, and conjunctival redness. The patient did not experience a recurrent episode of ventricular tachycardia following the block [Figure 1]. On day 16, she underwent a coronary angiogram, temporary pacemaker implantation (TPI), and cardiac resynchronization therapy with a pacemaker (CRT-P). This was not feasible in the presence of ongoing recurrent ventricular tachycardia. The patient was discharged on day 20 with a stable heart rate. She was evaluated in the outpatient department after two months, reporting no new complaints. Elective laparoscopic cholecystectomy is planned for one month from now.

Figure 1.

On day 2 post-stellate ganglion block with a long-acting local anaesthetic, sinus rhythm with LBBB and QRS prolonged

DISCUSSION

Sympathetic fibers that innervate the head, neck, and upper limbs originate from the initial thoracic segments and ascend via the sympathetic chains to synapse in the superior, middle, and inferior cervical ganglia, collectively constituting the cervical sympathetic chain. The stellate ganglion, also known as the cervicothoracic ganglion, is located on each side of the neck and results from the fusion of the inferior cervical ganglion with the first thoracic ganglion. It is located deep to the prevertebral fascia and is positioned medially and posteriorly to the carotid artery. The ganglion measures 1–2.5 cm in length and approximately 1 cm in width, exhibiting fusiform, triangular, or oval shapes. At the sixth cervical vertebra (C6), the transverse process features a bony structure referred to as the Chassaignac tubercle. The administration of local anesthetic around the stellate ganglion disrupts sympathetic outflow to the head, neck, and upper limbs by inactivating both preganglionic and postganglionic fibers. The stellate ganglion is situated near the pleural and vertebral artery. Given the significant risk of side effects, such as pneumothorax and vascular puncture, even with the “safer” C6 approach, an image-guided technique is highly recommended at a more cephalad position, near the middle cervical ganglion.[3]

Various methodologies exist for SGB utilizing fluoroscopy, CT, MRI, or ultrasound imaging.[4] Complications, including accidental intravascular injection, brachial plexus and recurrent laryngeal nerve palsy, and injury to the trachea and esophagus, are recognized, though they occur infrequently. Left SGB may lead to an imbalance in myocardial contractility and asynchrony of the left ventricle.[5] The literature provides substantial evidence that left stellate ganglionectomy, by increasing the ventricular fibrillation threshold, may serve as an alternative intervention for patients at high risk of sudden death due to ventricular arrhythmias unresponsive to medical therapy.[6,7] One study demonstrated the superiority of sympathetic blockade over the antiarrhythmic protocol of ACLS; however, the comparative efficacy of SGB versus ACLS guidelines remains to be established.[8]

The patient’s ongoing cholelithiasis and upper abdominal pain resulted in decreased appetite and food intake. Low serum potassium levels, in conjunction with a history of coronary artery disease, likely contributed to the recurrent ventricular tachycardia that was resistant to medical management and ablation, and was only temporarily resolved through cardioversion. After the ultrasound-guided stellate ganglion block [Figure 2], we successfully managed the recurrent ventricular tachycardias, allowing the patient to proceed with transvenous pacing implantation and cardiac resynchronization therapy with a pacemaker. This intervention would stabilize heart rate and enhance cardiac function and ejection fraction.[9]

Figure 2.

Ultrasound image of stellate ganglion block of our patient Stellate ganglion, longus colli muscle (LC), longus capitis muscle (LCa), carotid artery (C), and the anterior tubercle (AT) of the transverse process

CONCLUSIONS

One therapeutic option for refractory ventricular tachycardia that is not responding to medication or repeated shocks is the stellate ganglion block. However, before we can declare it a major treatment strategy for ventricular tachycardia, extensive case series and multicentric case reports need to be undertaken in the future.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.