Efficacy and safety of ultrasound guided stellate ganglion block: developing new clinical indications beyond electrical storm

Background Percutaneous stellate ganglion block (PSGB) is recommended by the latest European guidelines for patients with drug and ventricular tachycardia (VT) ablation refractory electrical storm (ES). Yet, due to the strong antiarrhythmic potential, combined with the good safety profile, we’ve recently used it for to the prophylaxis of ventricular arrhythmias (VAs) in high-risk patients and the prophylaxis/treatment of atrial arrhythmias in patients with acute heart failure (HF). Purpose To describe our single-center experience with PSGB usage outside the conventional indication of ES. Methods We hereby describe our single center experience with PSGB from 2/2021 to 2/2024. Results 56 patients (87% male, mean age 64 ± 12 years) received a total of 91 PSGB performed with the lateral, ultrasound (US) guided technique. Most of the procedures consisted of a single bolus anesthetic injection of lidocaine plus ropivacaine, 27% in an additional continuous infusion, mainly with ropivacaine. All procedures except for 3 in a single patient who had previously received left cardiac sympathetic denervation, were performed on the left side. Most of the patients (61%) suffered ischemic cardiomyopathy (CMP), including 11 with an acute coronary syndrome; the rest had non-ischemic CMP. 63 PSGB (69%) were performed in patients with impending or manifested cardiogenic shock (SCAI classification B or more). Mean LVEF was 24 ± 12%. Most of the procedures (n=80, 88%) were performed due to ongoing refractory VAs, yet 6 (6%) aimed to prevent major VAs in high-risk patients, mostly in the setting of recent ES (within 1 month) and need for Levosimendan to support cardiac output, in one case due to recent stereotactic VT ablation, to prevent early VAs in the phase of acute radiation induced microvascular damage. All 6 were effective in preventing clinically significant VAs. Additionally, 5 single bolus PSGBs (5%) were performed due to atrial arrhythmias with high ventricular rate despite intravenous drugs in the setting of acute HF. Specifically, 3 patients had atrial fibrillation (AF), 1 patient runs of ectopic atrial tachycardia (AT) and 1 patient 2:1 atrial flutter. Left-sided PSGB significantly reduced (≥25% reduction) ventricular rate during AF and AT but not during the single case of 2:1 atrial flutter, in 2/3 AF cases a cardioversion into sinus rhythm occurred within 40 minutes from PSGB. Only 1 (1%) major complication occurred (respiratory arrest), that was quickly and effectively treated with lipid emulsion, while minor complications were observed in 11% of PSGBs (mostly transient left arm weakness). Conclusions Our data suggest that US-guided PSGB usage, thanks to its feasibility at bed-side and good safety profile, may expand, beyond ES, to not only VAs prevention in high-risk settings, but also to prophylaxis/treatment of atrial arrhythmias in critically ill patients with acute heart failure requiring concomitant inotropic support.