Automated 3D analysis of multislice computed tomography to define the line of perpendicularity of the aortic annulus and of the implanted valve: benefit on planning transcatheter aortic valve replacement.

AIMS: We aimed to determine whether preprocedural analysis of multislice computed tomography (MDCT) scan could accurately predict the "line of perpendicularity" (LP) of the aortic annulus and corresponding C-arm angulations required for prosthesis delivery. METHODS AND RESULTS: A 3D analysis of preprocedural MDCT dedicated to define the LP of the aortic annulus was performed in 60 consecutive patients referred for transcatheter aortic valve replacement (TAVR). In 24 patients, the analysis was performed retrospectively to evaluate reproducibility. In 11 patients of this cohort, additional fluoroscopy and MDCT were performed postprocedure to compare the LP of the aortic annulus and the LP of the implanted bioprosthesis. In 36 patients, the analysis was performed prospectively and the results were available at the time of the procedure. In those 36 patients, the postprocedure fluoroscopy-defined LP of the implanted bioprosthesis was used to validate the LP of the aortic annulus as predicted by MDCT. Intraobserver and interobserver reproducibility of the 3D analysis of MDCT to define the LP of the aortic annulus (κ = 1 and 0.94, respectively) and of the bioprosthesis (κ= 1 and 1, respectively) were excellent. Comparison between the LP of the aortic annulus and the LP of the bioprosthesis showed that the two LPs were virtually identical, demonstrating both self-centering of the device during implantation and the possibility to use the LP of the implanted bioprosthesis as a surrogate of the LP of the aortic annulus. In the prospective cohort, the ability of MDCT analysis to predict the LP of the aortic annulus was very good (accuracy = 94% and κ = 0.89). CONCLUSION: Automated 3D analysis of preimplantation MDCT accurately predicts the LP of the aortic annulus and the corresponding C-arm position required for TAVR.

Automated 3D analysis of pre-procedural MDCT to predict annulus plane angulation and C-arm positioning: benefit on procedural outcome in patients referred for TAVR.

OBJECTIVES: The aim of this study was to determine whether pre-procedural analysis of multidetector row computed tomography (MDCT) scans could accurately predict the "line of perpendicularity" (LP) of the aortic annulus and corresponding C-arm angulations required for prosthesis delivery and impact the outcome of the procedure. BACKGROUND: Optimal positioning of the transcatheter aortic prosthesis is paramount to transcatheter aortic valve replacement (TAVR) procedural success. METHODS: All patients referred for TAVR at our center underwent a routine pre-procedural MDCT scan. A 3-dimensional (3D) analysis using software dedicated to define the LP of the aortic annulus and the corresponding C-arm positioning was performed in 71 consecutive patients. In 35 patients, the results of the MDCT analysis were not available at the time of the procedure (angiography cohort). In that cohort the position of the C-arm was determined during the procedure using ad-hoc angiography. In 36 patients, the MDCT analysis was performed pre-procedure and results were available at the time of the procedure (MDCT cohort). In that cohort the position of the C-arm was derived from the MDCT analysis rather than by ad-hoc angiography. RESULTS: Intraobserver and interobserver reproducibility of MDCT analysis to predict the LP of the aortic annulus were excellent (kappa = 1 and 0.94, respectively). Patient variations of the LP ranged >70°. Compared with the angiography cohort, the MDCT cohort was associated with a significant decrease in implantation time (p = 0.0001), radiation exposure (p = 0.02), amount of contrast (p = 0.001), and risk of acute kidney injury (p = 0.03). Additionally, the combined rate of valve malposition and aortic regurgitation was also reduced (6% vs. 23%, p = 0.03). CONCLUSIONS: Automated 3D analysis of pre-implantation MDCT accurately predicts the LP of the aortic annulus and the corresponding C-arm position required for TAVR. With this approach, the implantation of the balloon-expandable prosthetic valve can be performed without an aortogram in the majority of cases and still be safe, with a low rate of valve malpositioning and regurgitation.