Efficacy of percutaneous stellate ganglion block according to ventricular arrhythmia cycle length: a post-hoc sub-analysis of the STAR study.

Background: Data on the predictors of percutaneous stellate ganglion block (PSGB) efficacy in electrical storm (ES) are scanty.
Objective: To assess whether the PSGB efficacy is influenced by the arrhythmia type and cycle length prior to the procedure.
Methods: A sub-analysis of the multicenter STAR study. The population was stratified into 3 groups according to the median cycle length of the latest ventricular arrhythmia before PSGB: ventricular fibrillation (VF), fast-VT and slow-VT. The primary outcome was the number of treated arrhythmic episodes (with ATPs and/or DC-shocks) in the hour immediately after PSGB compared to the hour before.
Results: We considered 139 PSGBs from 112 patients divided in 51 VF, 44 fast-VT (VT cycle<375 msec) and 44 slow-VT (VT cycle≥375 msec). The number of treated arrhythmic episodes in the hour after every PSGB was significantly lower compared to the hour before in all groups [VF:0 (IQR,0-1) vs 5 (IQR,2-8), p<0.001; fast-VT:0 (IQR,0-0) vs 1 (IQR,0-6.5), p<0.001; slow-VT:0 (IQR,0-0) vs 1 (IQR,0-4.5), p=0.001]. Analyzing the reduction of the number of ATPs/DC-shocks from the hour before to the hour after PSGB, a significant trend was observed across the groups (Jonckheere-Terpstra trend p<0.001) and a significant difference was observed comparing slow-VT vs VF and fast-VT versus VF, but not comparing slow-VT versus fast-VT. VF was independently associated with the probability of reduction of treated event after PSGB.
Conclusion: PSGB is an effective treatment for ES in patients with all type of ventricular arrhythmias. However, its effectiveness was more pronounced in patients with VF.
(Copyright © 2024. Published by Elsevier Inc.)