Stellate ganglion block as a treatment for arrhythmic storm: an observational study

Revista Española de Anestesiología y Reanimación STELLATE GANGLION BLOCK AS A TREATMENT FOR ARRHYTHMIC STORM: AN OBSERVATIONAL STUDY. --Borrador del manuscrito-- Número del manuscrito: Tipo de artículo: Original Palabras clave: Tormenta arrítmica; tratamiento; bloqueo del ganglio estrellado; taquicardia ventricular. Electrical storm; treatment; stellate ganglion block; ventricular tachycardia. Autor correspondiente: José M López-Millán, M.D. Virgen Macarena University Hospital Sevilla, Sevilla SPAIN Primer autor: José M López-Millán, M.D. Orden de autores: José M López-Millán, M.D. Carmen Coca Gamito Alicia Cámara Faraig Ernesto Díaz Infante Juan Carlos García Rubira Resumen: Introducción La tormenta arrítmica es una urgencia vital. Cuando el tratamiento agudo convencional no es efectivo, el bloqueo del ganglio estrellado puede contribuir al control de la arritmia al proporcionar un bloqueo simpático visceral cervicotorácico. El objetivo de este estudio es valorar la efectividad y seguridad del bloqueo ecoguiado del ganglio estrellado para el tratamiento de la tormenta arrítmica refractaria. Método Seguimiento de una cohorte de pacientes con tormenta arrítmica que cumplen criterios para el bloqueo del ganglio estrellado. El bloqueo fue realizado guiado con ecografía a nivel C6 utilizando anestésico local y esteroide, primero en lado izquierdo y, si no respuesta, seguidamente en el lado derecho bilateralmente, y seguido de radiofrecuencia convencionalguiada mediante fluoroscopiaa nivel C7 si la respuesta al bloqueo fue faroable de forma transitoria con reaparición posterior de la arrítmia. Resultados Se incluyó a siete pacientes, con una mortalidad durante el ingreso del 14.29%. Cuatro pacientes recibieron bloqueo unilateral y tres bloqueo bilateral del ganglio estrellado.Seis recibieron ablación cardíaca y a uno de ellos se implantó un desfibrilador cardíaco automático. La tormenta arrítmica fue controlada termporalmente en todos los casos más allá de la duración del efecto anestésico local. Tres pacientes se sometieron a ablación por radiofrecuencia del ganglio estrellado y dos asimpatectomía torácica endoscópicadel ganglio estrellado.El único efecto adverso observado durante el estudio fue el síndrome de Horner después del bloqueo anestésico del ganglio estrellado.Dos pacientes fallecieron antes del alta y cuatro continúan de alta; tres de ellos sin reingreso posterior debido a eventos ventriculares desde hace más de dos años. Conclusión El bloqueo ecoguiado del ganglio estrellado es una técnica efectiva y segura para el Con tecnología de Editorial Manager® y ProduXion Manager® de Aries Systems Corporation tratamiento de la tormenta arrítmica refractaria como complemento al tratamiento cardiológico habitual. Revisores sugeridos: Jose Antonio De Andrés Ibañez, Catedrático de Universidad Jefe de Servicio de Anestesia, General University Hospital Consortium of Valencia [email protected] Por su elevada experiencia en anestesia regional ecoguiada y haber publicado un caso clínico relacionado con el presente estudio. Enrique Ortega Ladrón de Cegama, Profesor Asociado CIS Jefe de Sección de Anestesiología, Hospital del Rio Ortega de Valladolid [email protected] Por su elevada experiencia en técnicas de anestesia regional aplicada al tratamiento del dolor ecoguiadas y en particular en lesión de ganglio estrellado mediante radiofrecuencia. Con tecnología de Editorial Manager® y ProduXion Manager® de Aries Systems Corporation 4th July 2022. Dear Editor, With this letter, we offer our manuscript entitled “Stellate ganglion block as a treatment for arrhythmic storm. An observational study” for publication in Regional Anesthesia and Pain Management. The arrhythmic storm has a high mortality and despite its multiple treatments, scientific publications of high methodological Quality are scarce. Its low incidence, clinical and therapeutic variability, high mortality in the short and medium term, as well as the difficulty of blinding for interventional therapies and for placebo control, make of the utmost difficulty the study of the role that interventional blockade of the cardiac sympathetic nervous system can play on its treatment. We present a prospective observational study on a cohort of seven patients to whom we systematically applied the same ultrasound-guided regional stellate ganglion block technique, with the aim of evaluating its contribution to the effective control of refractory arrhythmia as complement to the standard cardiological treatment. In our series, symptom relief is 100% (p<0.05) and in-hospital survival is 85.71% in the absence of side effects. Although the sample is small and it is an observational study, the sample is homogeneous and with a prolonged followup. This manuscript has not been published either in whole or in part elsewhere nor has it previously been submitted for publication. All the authors listed on the cover have read the manuscript and I attest to the validity and legitimacy of the data. The content of this manuscript will not be submitted for possible publication in any other place while acceptance by the Journal of Pain is being considered. The authors declare that they have no conflict of interest. This study was carried out in accordance with STROBE recommendations (Strengthening the Reporting of Observational Studies in Epidemiology) for reporting observational studies. We hope you find our article of interest for your journal. Thank you in advance for your consideration. Yours sincerely, Jose M López-Millán COVER LETTER Ética de la publicación 1. ¿Su trabajo ha comportado experimentación en animales?: No 2. ¿En su trabajo intervienen pacientes o sujetos humanos?: Sí Si la respuesta es afirmativa, por favor, mencione el comité ético que aprobó la investigación y el número de registro.: HOSPITALES VIRGEN MACARENA Y VIRGEN DEL ROCÍO DE SEVILLA. Si la respuesta es afirmativa, por favor, confirme que los autores han cumplido las normas éticas relevantes para la publicación. : Sí Si la respuesta es afirmativa, por favor, confirme que los autores cuentan con el consentimiento informado de los pacientes. : Sí 3. ¿Su trabajo incluye un ensayo clínico?: No 4. ¿Todos los datos mostrados en las figuras y tablas incluidas en el manuscrito se recogen en el apartado de resultados y las conclusiones?: Sí Responsabilidades eticas STELLATE GANGLION BLOCK AS A TREATMENT FOR ARRHYTHMIC STORM: AN OBSERVATIONAL STUDY. Study Visual Abstract Stellate Ganglion Block (7) Unilateral (4/4) Bilateral (3/3) Stellate Ganglion Block (7) Unilateral (4) Conventional RF (1) No Conventional RF (3) Cardiac Ablation (2) Surgical Simpathectomy (1) No Cardiac Ablation (1) Surgical Simpathectomy (1) Bilateral (3) Conventional RF (2) Cardiac Ablation (2) Refractory AS, over 18 y/o Flow Diagram Efficacy of the SGB 7 patients meeting inclusion criteria for AS Graphical Abstract 1. TITLE: STELLATE GANGLION BLOCK AS A TREATMENT FOR ARRHYTHMIC STORM: AN OBSERVATIONAL STUDY. 2. AUTHORSHIP: López-Millán Infantes JM (1), Coca-Gamito C (2), Cámara-Faraig A (3), Díaz-Infante E (4), García Rubira JC (5). 1. Department of Anaesthesiology-Critical Care and Pain Medicine. Virgen Macarena University Hospital. 3 Dr. Fedriani Ave. Seville, Spain. 41009. Associate Professor at the University of Seville. Seville. Spain. [email protected]. http://orcid.org/0000-0001-7999-2257 Phone number: (+34) 616064122. Address: 21 Faustino Álvarez Street. 41002 Sevilla. Spain. Corresponding Author. 2. Department of Anaesthesiology-Critical Care and Pain Medicine. Virgen Macarena University Hospital. 3 Dr. Fedriani Ave. Seville, Spain. 41009. Anaesthesiologist. Pain Specialist. [email protected] 3. Department of Anaesthesiology-Critical Care and Pain Medicine. Virgen Macarena University Hospital. 3 Dr. Fedriani Ave. Seville, Spain. 41009. Anaesthesiologist. Pain Specialist. [email protected] 4. Department of Cardiology. Arrhythmia Unit. Virgen Macarena University Hospital. 3 Dr. Fedriani Ave. Seville, Spain. 41009. Cardiologist. Head of Unit. [email protected]. http://orcid.org/0000-0002-2736-5670 5. Department of Cardiology. Coronary Unit. Virgen Macarena University Hospital. 3 Dr. Fedriani Ave. Seville, Spain. 41009. Cardiologist. Head of Unit. [email protected]s. http://orcid.org/0000-0002-0407-1127 3. AUTHOR’S CONTRIBUTIONS LMJM and CGC performed analgesia techniques. DIE performed cardiac ablation techniques. GRJC performed non-interventional treatment. The authors participated on design and study implementation. CFA participated collecting data as independent investigator. LMJM, CGC, DIE, GRJC and CFA, all provided input on writing and reviewing the final version of this manuscript. All authors listed meet the authorship criteria according to the latest guidelines of the International Committee of Medical Journal Editors. All authors agree with the manuscript. 4. CONFLICT OF INTEREST No conflicts of interest have been declared by the authors. 5. FUNDING STATEMENT This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. PRIMERA PÁGINA 6. KEY WORDS Electrical storm, treatment, stellate ganglion block, ventricular tachycardia. 7. MANUSCRIPT WORD COUNT 2917 words. 1 1. TITLE: STELLATE GANGLION BLOCK AS A TREATMENT FOR ARRHYTHMIC STORM: AN OBSERVATIONAL STUDY. 2. ABSTRACT: Introduction: Arrhythmic storm is a vital emergency with high mortality. When acute conventional treatment is ineffective, the stellate ganglion block can contribute to the control of the arrhythmia by providing a visceral cervicothoracic sympathetic block. The objective of the study is to assess the effectiveness and safety of stellate ganglion block for the treatment of refractory arrhythmic storm. Method: Follow up of a cohort of patients with refractory arrhythmic storm that met criteria for performing stellate ganglion block. The block was ultrasound-guided at C6 level using local anaesthetic and steroid, left unilateral first, bilateral if no response, and followed by fluoroscopy-guided radiofrequency ablation at C7 if favourable response but subsequent relapse. Results: Seven patients were included, with a mortality rate during admission of 14.29%. Four patients received unilateral and three bilateral stellate ganglion blocks. Six were ablated and one of them had an implanted cardioverter-defibrillator. Arrhythmic storm was controlled temporarily beyond the effect of the local anaesthetic in all patients. Three underwent radiofrequency ablation and two underwent surgical thoracic sympathectomy. Only side effect was Horner’s syndrome observed in all the cases after stellate ganglion block with local anaesthetic. Two died after discharge and four continue at home, three of them without admission due to ventricular events for more than 2 years. Conclusion: Ultrasound-guided stellate ganglion block is an effective and safe technique in the treatment of refractory arrhythmic storm as a complement to the usual cardiologic treatment. Keywords: Electrical storm, treatment, stellate ganglion block, ventricular tachycardia.  What is already known on this topic: The benefit of stellate ganglion block in the acute treatment of arrhythmic storm has been demonstrated, although with a variable response depending on the technique used.  What this study adds: This study evaluates the effectiveness and safety of ultrasoundguided stellate ganglion block for the treatment of refractory arrhythmic storm in a cohort of patients using a standardized technique in a multidisciplinary approach with a long-term follow-up. Manuscrito (anónimo) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2  How this study might affect research, practice or policy: Ultrasound-guided stellate ganglion block is an effective and safe technique in the acute treatment of refractory arrhythmic storm as a complement or as a bridging therapy to definitive cardiological treatment of the arrhythmia. The long-term role of RF stellate ganglion injury remains to be determined. 3. INTRODUCTION Arrhythmic storm (AS) is a life-threatening emergency defined as three or more episodes of ventricular tachycardia (VT), ventricular fibrillation (VF), or implantable cardioverterdefibrillator (ICD) discharges in 24 hours (1). It has an incidence of 10-20% in patients with ICDs for secondary prevention and around 4% in patients with ICDs for primary prevention (2). It presents an overall mortality that ranges between 20 and 50% depending on the series. According to the SHIELD study, only in 13% of patients, a reversible cause can be identified (3). Some of the predictors are: advanced age, left ventricular systolic dysfunction, previous episodes of VT/VF, cardiac ischemia, renal failure, hyper or hypokalaemia (4). The relevance of sympathetic hyperactivity is variable and depends on the type, aetiology, mechanism of the underlying arrhythmia and the clinical setting (5). The main goal of acute treatment is hemodynamic stabilization and prevention of recurrence through antiarrhythmic drug therapy, ICD reprogramming, sedation, and systemic adrenergic tone containment or ventricular assist. Catheter ablation is essential to ensure electrical stability, reduce recurrences, and improve survival (6). When the above measures are not effective, other therapies can reduce cardiac sympathetic activity such as continuous epidural anaesthesia, surgical thoracic sympathectomy by endoscopic thoracoscopy (ETS) or radiofrequency ablation of the stellate ganglion and can significantly reduce, and for a variable period of time, time the recurrence of AS in open prospective studies (5) and in isolated clinical cases (7, 8). The benefit of stellate ganglion block (SGB) in the acute treatment of AS has been demonstrated, although with a variable response depending on the technique used (9). The type of local anaesthetic used, the use of adjuvants, unilateral or bilateral, continuous or bolus block, guided by ultrasound, fluoroscopy or by anatomical references, and the performance of 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 9 remaining asymptomatic at 31 months of follow-up. We do not know what would have happened if we had not done it or if we had performed an RFC technique. Should be highlighted the low mortality (14.27%) during admission in comparison with the series by García-Morán, et al. (20) which could be the result of the standardized and coordinated multidisciplinary strategy with the Arrhythmia Unit and the Coronary Unit in the acute phase. Of the four patients currently in follow-up, three underwent cardiac ablation. The patient who was not ablated received a bilateral sympathectomy. Two patients received RFC, one delayed unilateral and the other bilateral. The only patient with ischemic aetiology received bilateral SGB, underwent cardiac rehabilitation, continued without arrhythmic events, and has not been re-admitted. The follow-up time without hospital admissions for arrhythmias is greater than two years in three of the four patients The other patient had an admission for arrhythmias after discharge, currently has 5 months of follow-up without arrhythmias, and is awaiting a heart transplant. In the study by García-Morán et al. (20), a retrospective series of 8 patients, mortality is 50% and follow-up is only greater than one year in one patient. In general, follow-up in published cases is short, even after performing radiofrequency, as in the case of Trejo-Velasco et al., (18) at 4 months, or it is not collected, as in the case of Mata et al., (16) because they focus on the result obtained in the acute phase of AS during admission. The treatment of AS is complex and usually requires combining different therapies until a successful result is achieved, so it is recommended that the approach be multidisciplinary (23). Despite its high safety profile compared to other interventional alternatives (24), the volume of local anaesthetic could be optimized to maintain a reliable efficacy reducing mild side effects in our study (25). Although it presents important methodological limitations because it is an observational study on a very small descriptive cohort of patients, it nonetheless presents few losses during admission and prolonged follow-up with 75% of patients still active. The positive results obtained support the benefit SGB can provide in the acute treatment of AS as a complement to definitive cardiological treatment or as bridging therapy. 7. CONCLUSION 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 10 Ultrasound-guided stellate ganglion block is an effective and safe technique in the acute treatment of refractory arrhythmic storm as a complement or as a bridging therapy to definitive cardiological treatment of the arrhythmia. The long-term role of RF stellate ganglion injury remains to be determined. Larger studies of higher methodological quality are still needed. 8. ACKNOWLEDGMENTS None. 9. REFERENCES 1. Zipes DP, Camm AJ, Borggrefe M, Buxton AE, Chaitman B, Fromer M, et al., American College of Cardiology; American Heart Association Task Force; European Society of Cardiology Committee for Practice Guidelines. ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. J Am Coll Cardiol. 2006;48: e247-346. 2. 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EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias: developed in a partnership with the European Heart Rhythm Association (EHRA), a Registered Branch of the European Society of Cardiology (ESC), and the Heart Rhythm Society (HRS); in collaboration with the American College of Cardiology (ACC) and the American Heart Association (AHA). Heart Rhythm 2009;6: 886–933. 24. Goel V, Patwardhan AM, Ibrahim M, Howe CL, Schultz DM, Shankar H. Complications associated with stellate ganglion nerve block: a systematic review. Reg Anaesth Pain Med. 2019; 44: 669–78. 25. Yongiae Yoo, Chang-soon Lee, Yong-Chui Kim, Jee Youn Moon, Finlayson RJ. A randomized comparison between 4, 6 and 8 mL of local anaesthetic for ultrasoundguided stellate ganglion block. J Clin Med. 2019;8(9):1314. 10. TABLES. ID Sex Age AHT DLP Smoking OH DM LVEF Cardiological history ICD 1 H 63 No No No Yes No 47 No 2019 2 M 73 Yes Yes Yes Yes Yes 25 MI + PCI + Dilated M 2008 3 H 72 Yes Yes Yes Yes No 21 Dilated M + VF + Atrial flutter + PCI 2007 4 H 75 Yes Yes Yes Yes Yes < 25 AMI + Dilated M + MI + PHT 2014 5 H 54 Yes Yes Yes No Yes > 60 MHO + AF 2011 6 H 75 Yes Yes Yes Yes No 40 AF + Dilated M + PCI + ICD 2013 7 H 63 Yes Yes No No Yes 25 Dilated M + ICD + PCI + AF + iatrogenic tamponade 2014 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 13 Table 1. Characteristics of patients. DLP: dyslipidaemia; OH: alcohol consumption; DM: diabetes mellitus; Dilated M: dilated myocardiopathy; MI: myocardial infarction; PCI: percutaneous coronary intervention; AF: atrial fibrillation; LVEF: Left ventricular ejection fraction; ICD: implantable cardioverter-defibrillator. ID Drugs Side Relief (days) RF Ablation STQ Final Relief (months) Exitus 1 Bupivacaine 0.25% 8 ml+DXM 4mg Bilateral 4 No Yes No 26 No 2 Bupivacaine 0.25% 7 ml+BMT 6mg Unilateral left 17 Yes, left Yes, two No 24 No 3 Bupivacaine 0.25% 8 ml+DXM 4mg Unilateral left 8 No Yes T1-T5 bilateral 12 Yes 4 Bupivacaine 0.25% 10 ml+DXM 4mg Unilateral left 11 No Yes No 0 Yes 5 Bupivacaine 0.25% 10 ml+BMT 6mg Unilateral left > 60 No No T2-T4 bilateral 34 No 6 Bupivacaine 0.25% 8 ml+DXM 4mg Bilateral 4 Yes, bilateral Yes, two No 4 Yes 7 Bupivacaine 0.25% 10 ml+DXM 4mg Bilateral 9 Yes, bilateral No No 6 No Table 2. Intervention on the stellate ganglion and results. 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