Abstract 13434: Relationship Between Fluoroscopy Time, Absorbed Dose And Effective Dose In A High-volume Electrophysiology Laboratory

Abstract

Introduction: It is important to correctly quantify radiation exposure to assess the deterministic (tissue damage) and stochastic (cancer and genetic changes) risk associated with fluoroscopy use. Hypothesis: There is little correlation between fluoroscopy time and both the absorbed dose (AD; deterministic risk) and the effective dose (ED; stochastic risk) measured during EP procedures. Methods: A retrospective analysis of radiation dose data for subjects undergoing EP procedures in which fluoroscopy was used. Data collected included fluoroscopy time (min), dose area product (DAP - Gy*cm 2 ) and AD or air kerma (AK - mGy). The ED was calculated by multiplying DAP with a conversion factor of 0.20 mSv/(Gy*cm 2 ). Results: 3331 consecutive EP procedures were analyzed. Overall, the correlation between DAP/ED and AD is strong (r = 0.63, P < .000001), while between fluoroscopy time and AD is moderate (r = 0.46, P < .000001), and between fluoroscopy time and DAP/ED is weak (r = 0.26, P < .000001). There were wide variations in dose and statistically significant differences in fluoroscopy time, DAP/ED, and AD depending on the nature of the procedure, with AF ablation conferring the highest values, followed by BIV implant, LAA exclusion and VT ablation procedures (Table). When considering AF ablation procedures, radiation exposure was found to be highly operator dependent (Figure). Conclusions: Fluoroscopy time does not correlate well with both ED and AD. Therefore, it shouldn’t be the sole indicator of radiation exposure reported for EP procedures, as it does not accurately reflect neither the stochastic nor the deterministic risk.