Operator Radiation Exposure During Transfemoral Transcatheter Aortic Valve Replacement

Abstract

Background: The level of radiation exposure received by operators performing transcatheter aortic valve replacement (TAVR) is not well investigated. The aim of this study is to measure the amount of radiation received by operators performing transfemoral TAVR and to identify various patient and procedural characteristics associated with increased radiation exposure.

Methods: Primary (operator 1) and secondary (operator 2) operators' equivalent radiation doses in micro Sieverts (µSv) were calculated prospectively using real-time radiation dosimeters for a total of 140 consecutive transfemoral TAVRs. Corresponding eye and thorax radiation exposures between the operators were compared. Associations between various patient and procedural characteristics and the radiation exposure were tested using the t-test and Wilcoxon Mann-Whitney rank-sum test with Monte Carlo estimation. Multivariable regression analysis was also conducted.

Results: Operator 1 had significantly higher cumulative equivalent radiation exposure than operator 2 (86 µSv vs 38 µSv, p-value: <0.0001) which was consistent at the level of the thorax (67 µSv vs 22 µSv, p-value: <0.0001), but not at the level of the eye (16.5 µSv vs 15 µSv, p-value: 0.30). On multivariable analysis, patient obesity and intraprocedural complications were associated with higher radiation exposure to both operators. Ad hoc percutaneous coronary intervention led to excessive radiation exposure to the secondary operator.

Conclusions: Transfemoral TAVR is associated with a modest amount of radiation exposure to operators and is significantly higher for the primary operator than for the secondary operator.

Keywords: Obesity; Radiation exposure; TAVR.

Figure 1

Radiation measurement using real-time dosimeters.

Figure 2

Total equivalent radiation dose for operator 1 vs. operator 2 performing transfemoral TAVR. (The diamond denotes the mean. The top and the bottom ends denote the first and third quartiles. The whiskers are the maximum and minimum values closest to the upper and lower fence. The upper fence is obtained by adding the value of 1.5 times the interquartile range added to the third quartile. The lower fence is obtained by subtracting 1.5 times the interquartile range from the first quartile. The circles denote the outliers that are beyond the fences). Abbreviation: TAVR, transcatheter aortic valve replacement.

Figure 3

Total equivalent radiation dose for operator 1 vs. operator 2 at the thorax level. (The diamond denotes the mean. The top and the bottom ends denote the first and third quartiles. The whiskers are the maximum and minimum values closest to the upper and lower fence. The upper fence is obtained by adding the value of 1.5 times the interquartile range added to the third quartile. The lower fence is obtained by subtracting 1.5 times the interquartile range from the first quartile. The circles denote the outliers that are beyond the fences).

Figure 4

Total equivalent radiation dose for operator 1 vs. operator 2 at the eye level. (The diamond denotes the mean. The top and the bottom ends denote the first and third quartiles. The whiskers are the maximum and minimum values closest to the upper and lower fence. The upper fence is obtained by adding the value of 1.5 times the interquartile range added to the third quartile. The lower fence is obtained by subtracting 1.5 times the interquartile range from the first quartile. The circles denote the outliers that are beyond the fences).