Radioprotective lightweight caps in the interventional cardiology setting: a randomised controlled trial (PROTECT)

AIMS: The aim of this study was to test the radioprotection efficacy and comfort of newer bilayer barium sulphate-bismuth oxide composite (XPF) caps in an interventional cardiology setting. METHODS AND RESULTS: Operators were randomly assigned to wear standard fabric (n=59), 0.3 mm (n=74), or 0.5 mm (n=64) lead-equivalent XPF caps. Radiation doses were measured by using dosimeters placed outside and underneath the caps. Wearing comfort was assessed at the end of each measurement on a visual analogue scale (VAS) (0-100, with 100 indicating optimal comfort). Procedural data did not differ between the XPF and standard groups. Mean standard, XPF 0.3 mm, and XPF 0.5 mm cap weights were 12.5 g, 118.4 g, and 123.7 g, respectively. VAS comfort ratings of the standard and XPF caps did not differ significantly (p=0.272). The mean radiation protection was 12.0%, 95% CI: 4.9-19.1% (standard caps, n=35), 91.5%, 95% CI: 87.4-95.6% (XPF 0.3 mm caps, n=45) and 97.1%, 95% CI: 92.5-100% (XPF 0.5 mm caps, n=44) (p≤0.001 for all group comparisons). Using the XPF caps, a cumulative total radiation dose reduction by almost factor 10 was evident (272 procedures, 22,310 μSv outside the XPF caps, 2,770 μSv inside the caps). CONCLUSIONS: Lightweight XPF caps show comparable comfort to standard fabric caps, but provide substantial radiation protection during fluoroscopy-guided cardiac interventions.