Impact of access site selection and operator expertise on radiation exposure; a controlled prospective study

Published data relating to arterial access site selection and radiation exposure during coronary procedures suggest radial access may lead to increased radiation exposure, but this is based on poorly controlled studies. We sought to measure radiation exposure to patients and operators during elective coronary angiography (CA) according to access site, with other procedure related variables controlled for. We also investigated the specific effect of operator expertise in relation to radiation exposure.

100 consecutive patients undergoing first time elective CA were recruited prospectively. An expert transradial (TR) and an expert transfemoral (TF) operator performed 25 cases each via their default route. A trainee cardiologist with intermediate experience in both access sites performed 25 cases via each route. Angiographic projections were standardised and optimised radiation protection was utilised for all procedures. The primary endpoints were operator and patient exposure, quantified by effective dose (ED) and dose area product (DAP) respectively. Secondary endpoints included fluoroscopy time (FT) and time to patient ambulation.

The trainee operator recorded higher values for radiation exposure in radial and femoral cases when compared to the expert operators. There were no significant differences in radiation exposure during CA to operator or patient according to access site when standardised by operator experience. For the trainee, ED for TR and TF procedures was 8.8 ± 4.3 μSv and 8.5 ± 6.5 μSv (P = .86) and DAP was 25.4 ± 4.8 Gycm(2) vs 25.2 ± 8.3 Gycm(2) (P = .9). For the expert TR and TF operators, ED was 6.4 ± 4.7 μSv vs 6.1 ± 5.6 μSv (P = .85) and DAP was 21.7 ± 6.5 Gycm(2) vs 22.4 ± 8.0 Gycm(2), (P = .74). There was no significant difference in FT in relation to access site. Time to ambulation was significantly longer with TF access.

The use of TR access has no adverse effect on radiation exposure or FT for diagnostic CA, but does allow for quicker ambulation compared to TF access. The magnitude of radiation exposure is related to operator expertise for both access sites. The results of previous studies reflect the effect of uncontrolled patient and operator variables and not access site selection.