MDCT planning of trans catheter aortic valve implantation (TAVI): determination of optimal c-arm angulation

A fluoroscopic view perpendicular to the aortic valve annulus is required during transcatheter aortic valve implantation (TAVI) for obtaining an optimal deployment of the bioprosthesis. By predicting c-arm angulation, pre-procedural MDCT could decrease the number of aortograms, shorten the time of the procedure and reduce the amount of intra-arterial contrast agent. The aim of our study was to assess the accuracy of MDCT in predicting c-arm angulation at the cath. lab. In this single center study, we investigated MDCT prediction of c-arm angulation in patients having undergone a TAVI procedure using SAPIEN 3® (Edwards Lifesciences, USA). Prior to the procedure, an experienced radiologist had reported the angulation using dedicated software (CT_report). After the procedure, a blinded experienced radiologist retrospectively measured the angles using the same method (CT_study). Interobserver variability was drawn from the comparison between CT_report and CT_study. Then, the mean angular difference between the predicted MDCT angles (CT_study) was compared to the working view recorded at the cath. lab. Seventy-nine patients (M/F = 0.65; mean age: 85.2 years ± 5.3) were included. Interobserver variability was 5.9 ± 6.1°. The mean absolute difference between MDCT and fluoroscopy was 8.8 ± 7.1°. The present study showed that MDCT could predict the coplanar fluoroscopic angles prior to TAVI using a balloon-expandable bioprosthesis Sapien 3® placed via a transfemoral approach with a mean angular difference of 8.8 ± 7.1°. Reproducibility was considered good as the mean difference between two independent measures was 5.9 ± 6.1°.