A Meta-analysis of the Efficacy and Safety of Stereotactic Arrhythmia Radioablation (STAR) in Patients with Refractory Ventricular Tachycardia

Reports of stereotactic arrhythmia radioablation (STAR) in patients with refractory ventricular tachycardia after catheter ablation are limited to small series. Here, we carried out a systematic review and meta-analysis of studies to better determine the efficacy and toxicity of STAR for ventricular tachycardia.Following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) and the Meta-analyses Of Observational Studies in Epidemiology (MOOSE) guidelines, eligible studies were identified on Medline, Embase, Cochrane Library and the proceedings of annual meetings to 10 February 2023. Efficacy was defined as a ventricular tachycardia burden reduction >70% at 6 months; safety was defined as <10% of any grade ≥3 toxicity.Seven observational studies with a total of 61 patients treated were included. At 6 months, the ventricular tachycardia burden reduction was 92% (95% confidence interval 85-100%) and use of fewer than two anti-arrhythmic drugs was seen in 85% (95% confidence interval 50-100). Six months after STAR, an 86% reduction (95% confidence interval 80-93) in the number of implantable cardioverter-defibrillator shocks was observed. The rates for improved, unchanged and decreased cardiac ejection fraction were 10%, 84% and 6%, respectively. Overall survival at 6 and 12 months was 89% (95% confidence interval 81-97) and 82% (95% confidence interval 65-98). The cardiac-specific survival at 6 months was 87%. Late grade 3 toxicity occurred in 2% (95% confidence interval 0-5%) with no grade 4-5 toxicity.STAR demonstrated both satisfactory efficacy and safety for the management of refractory ventricular tachycardia and was also associated with a significant decline in anti-arrhythmic drugs consumption. These findings support the continued development of STAR as a treatment option.