Abstract 20780: 3D Analysis of Pre-Procedural Multislice Computed Tomography to Predict Annulus Plane Angulation and C-arm Positioning: Benefit on Safety Procedural Outcome in Patients Referred for Tanscatheter Aortic Valve Implantation (TAVI).
Positioning the X-ray tube C-arm perpendicular to the aortic annulus plane is key to achieve an appropriate delivery of the Edwards-SAPIEN valve during TAVI. This step requires performing angiographies in different angulations of the C-arm. We hypothesized that 3 D analysis of pre-procedural CT scan could be used to define the plane of the aortic annulus plane, the corresponding C-arm angulations, and could improve the safety outcome of the procedure.
Methods: All patients referred for TAVI in our center undergo CT scan as part of the preprocedural screening. A dedicated 3D analysis using a software updated to define aortic annulus plane and the corresponding c-arm positioning (3mensio Valves softwareTM) was performed in 37 consecutive patients; retrospectively in 23 and prospectively in 14. The retrospective cohort was used to validate the method. The predictive value and the benefit were tested in the prospective cohort using the last 14 patients of the retrospective cohort as controls.
Results: In the retrospective cohort we demonstrated 1) a very good intraobserver (23/23, Kappa = 1) and interobsever (22/23, Kappa =0.91) reproducibility and a very good accuracy (22/23, Kappa =0.91) of 3D CT analysis in defining the aortic plane angulation by comparison with X-ray; 3) heterogeneity of the orientation of the aortic plane from patient to patient with a range of 70° in the cranio/caudal axis and 80° in the right/left axis. In the prospective cohort pre-intervention 3D analysis of the CT allowed us to predict the position of the C-arm in 13/14 (93%) of the cases. By comparison with controls, 3D analysis of the CT aortic plane was associated with a decrease of the duration of the implantation phase by 36% (25±7 vs 39±14 min, p=0.001), X-ray exposure by 50% (804±519 vs 1611±1058 mGray, p=0.01), amount of contrast media by 50% (103±36 vs 207±98 ml, p=0.01) and post procedural creatinine rise by 63% (21±49 vs 57±71 μmol/l, p=0.01).
Conclusions: 3D analysis of pre-implantation CT predicts accurately the angulation of the aortic annulus and the corresponding C-arm position of the X-ray tube required for TAVI. Such an approach improves key safety parameters such as the duration of the implant, X-ray exposure, amount of contrast media and kidney toxicity.
- © 2010 by American Heart Association, Inc.