Percutaneous stellate ganglion block and catheter ablation timing: new insights from the STAR study

Background Cather ablation (CA) and percutaneous stellate ganglion block (PSGB) proved effective in fighting electrical storm (ES). So far neuromodulation is recommended in case of recurrences after catheter ablation, at least for monomorphic ventricular tachycardia. However, it is also known that the presence of ES significantly increases the risk an urgent CA. We sought to evaluate the best time sequence between CA and urgent PSGB (within the same admission) in terms of survival at discharge. Materials and methods We considered all the patients enrolled in the multicentre observational STAR study from January 2017 to April 2024. Patients were categorised according to the timing of PSGB and CA into four groups: CA only before PSGB; CA only after PSGB; only PSGB without CA and CA before and after PSGB. The primary outcome was survival to hospital discharge. Univariable and multivariable logistic regression model were run to address the correlation with the probability of survival to hospital discharge. Results We enrolled 298 patients, mainly males (246,87%), median age 68 years, (IQR 58-77 years) and median left ventricle ejection fraction (LVEF) 30% (IQR 20%-40%), 40% with an ICD. Of them, 94 (31%) underwent at least one CA (17 only before PSGB, 58 only after PSGB and 19 before and after PSGB); 204 did not receive any CA. The rate of in hospital mortality was 25%. Patient treated with CA at any time showed a significantly higher survival compared to patients who did not receive any CA (83% vs 71%, p=0.03). At univariable analysis CA at any time [OR 2 (95%CI 1.1-3.8), p=0.03] and CA after PSGB [OR 2.7 (95%CI 1.2-6.4), p=0.02] were significantly associated with the probability of survival. At multivariable analysis, after correction for age, centre, cause of ES, left ventricle ejection fraction and comorbidities, only CA after PSGB was associated with an increased probability of survival to hospital discharge [OR 3 (95%CI 1.1-8.8), p=0.038] (figure1) Conclusions Catheter ablation and stellate ganglion block are allies in the fight against electrical storms. However, our results suggest that the best sequence is to stabilise the patients with PSGB and then refer them for urgent catheter ablation.