Standardization of stereotactic arrhythmia radioablation (STAR): a systematic meta-review on reporting quality and adherence to EHRA and ICRU recommendations on behalf of the STOPSTORM.eu consortium

Background/introduction Stereotactic arrhythmia radioablation (STAR) is increasingly used for refractory ventricular tachycardia (VT), but workflows and reporting remain highly variable. Standardized reporting is essential to capture and compare emerging data. The European Heart Rhythm Association (EHRA) recently proposed core workflow and reporting items, and technical guidance exists from the International Commission on Radiation Units and Measurements (ICRU) report 91. Building on these frameworks and items identified within the STOPSTORM.eu consortium, we evaluated current STAR reporting quality, adherence to recommendations, and missing key elements to guide future standardization and enable evidence-based comparison of outcomes across studies and patient populations. Purpose To systematically review published STAR studies for workflow diversity, reporting completeness, and adherence to EHRA and ICRU recommendations. Methods A systematic search of PubMed, Embase, and Scopus (January 2025) identified studies reporting STAR for VT. Data were extracted on patient demographics, diagnostic workup, target delineation, and treatment planning, including adherence to EHRA and ICRU recommendations. When multiple reports from the same study existed, the most recent publication was analyzed, with earlier references considered for context. Case reports were included irrespective of potential overlap. Two independent reviewers conducted all screening and extraction steps with discrepancies resolved by consensus. Results Of 1309 individual records, 121 full-texts were reviewed, and 84 included. Age and sex were reported in 94% and 90% of studies, respectively, while key clinical variables such as specific cardiomyopathy type (62%), NYHA class (40%), and antiarrhythmic drug dose before STAR (23%) were inconsistently documented. Computed tomography (86%) and electroanatomical mapping (81%) were the most common modalities for clinical target volume (CTV) delineation, followed by electrocardiography (46%) and magnetic resonance imaging (43%). Explanations of each modality’s contribution to target definition were provided in 67% of cases - highest for echocardiography (83%) and lowest for single-photon emission computed tomography (47%). Overall, adherence to EHRA/ICRU recommendations was limited, particularly regarding detailed reporting of target definition rationale and treatment planning parameters. Margins were inconsistently defined, organs at risk constraints and outcomes were often not reported and dose prescriptions were poorly described. Conclusion Current STAR literature demonstrates substantial heterogeneity and incomplete recording, with limited adherence to existing recommendations. Critical reporting gaps were identified that must be addressed to ensure transparency and reproducibility. These findings will guide the development of consensus reporting standards on behalf of the STOPSTORM.eu consortium.