Trends in Radiation Exposure With the Refinement of Radiation Exposure Categories in Congenital Cardiac Catheterization: Insights From the CRISP Registry

Abstract Background The Congenital Cardiac Catheterization Project on Outcomes (C3PO) registry proposed 3-tier radiation exposure categories (REC: I [low], II [medium], and III [high]) consisting of 40 procedure types. This study sought to evaluate the recent trend of radiation exposure in the Catheterization Risk Score for Pediatrics (CRISP) registry organized by the Congenital Cardiovascular Interventional Study Consortium. Methods The analysis was conducted on a comprehensive data set from the CRISP registry, covering 13 institutions from January 1, 2016, to December 31, 2020. Radiation dosage in μGym²/kg was evaluated by REC, time, and institutions. The study period was divided into the first half (S1: 1/2016-6/2018) and the second half (S2: 7/2018-12/2020). Radiation dosage was compared between S1 and S2. Radiation reduction practices were assessed at participating centers through a questionnaire. Results Among 20,524 cases, the majority (n = 18,603, 90.2%) were assigned to C3PO REC procedure types. From S1 (n = 8956) to S2 (n = 9647), median radiation dosage significantly improved in all 3 tiers (P < .001): (1) REC I, −18%; (2) REC II, −33%; and (3) REC III, −30%. REC successfully stratified cases by median radiation dosage: (1) REC I, 18.2 μGym²/kg (n = 14,234); (2) REC II, 49.8 μGym²/kg (n = 3012); and (3) REC III, 67.0 μGym²/kg (n = 1357) but showed significant intraclass variability and heterogeneity. REC I exhibited the most variability in radiation dosage. To address these limitations, the procedures were organized into 6 updated REC categories (CRISP REC). Conclusions A significant reduction in radiation dosage was observed in the CRISP registry, although a few centers showed a trend of increasing radiation dosage. Despite its limitations, the C3PO REC provides a practical way to stratify cases for reporting dosage. We propose the CRISP REC as a refined alternative to the C3PO REC to improve stratification and decrease variability in radiation exposure across different categories.