Electrophysiological procedures for the use of the RPC: without hindrance and negligible radiation

Background: Fluoroscopy is the main visualization technique for EP procedures. A radiation protection cabin (RPC) shielded with 2 mm lead-equivalent walls was tested as an alternative protection tool (Cathpax®, Lemer Pax). Methods: To assess the scattered radiation to the operator inside the RPC an electronic personal dosimeter (EPD; Mk2, Thermo Electron) was placed at the neck level of the operator. A second EPD was located outside the RPC at 150 cm height from the floor, to record the presumable head radiation dose. Results: Radiation doses were measured in a total of 138 consecutive patients (age 54±16 yrs, BMI 28±5 kg/m2 (18-45), 64% male) undergoing a variety of ablation procedures (SVT=75, AFL=32, AF=17, VT=14). Median fluoroscopy time was 39 min (7-140), the cumulative dose-area product (DAP) 4702 cGy.cm2 (493-65620). Doses outside the RPC showed a median of 135 µSv (1-4881). Doses inside the RPC were detected only at sensitivity threshold or background levels (mean 0.2SD0.7 µSv, median 0.0, range 0-4). The dose reduction to the operator was highest for AF ablations (354 vs 0.5 µSv, respectively; p<0.001). The total accumulated dose outside the RPC was 37883 µSv for all 138 procedures, whereas for the protected operator inside only 30 µSv. Conclusions: There were highly concordant low dose values measured for the operator inside the RPC in comparison to high doses outside the RPC. The use of a RPC represents a major benefit over a lead apron and contributes to a significant dose reduction as low as reasonably achievable (ALARA principle).