Role of computed tomography in planning the appropriate x-ray gantry for quantitative aortography of post-transcatheter aortic valve implantation regurgitation

Background: The clinical robustness of contrast-videodensitometric (VD) assessment of aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) has been demonstrated. Correct acquisition of aortic root angiography for VD assessment, however, is hampered by the opacified descending aorta and by individual anatomic peculiarities. The aim of this study was to use preprocedural multi-slice computed tomography (MSCT) to optimize the angiographic projection in order to improve the feasibility of VD assessment. Methods and Results: In 92 consecutive patients, post-TAVI AR (i.e., left ventricular outflow tract [LVOT] AR) was assessed on aortic root angiograms using VD software. The patients were divided into 2 groups: The first group of 54 patients was investigated prior to the introduction of the standardized acquisition protocol; the second group of 38 consecutive patients after implementation of the standardized acquisition protocol, involving MSCT planning of the optimal angiographic projection. Optimal projection planning has dramatically improved the feasibility of VD assessment from 57.4% prior to the standardized acquisition protocol, to 100% after the protocol was implemented. In 69 analyzable aortograms (69/92; 75%), LVOT-AR ranged from 3% to 28% with a median of 12%. Inter-observer agreement was high (mean difference±SD, 1±2%), and the 2 observers’ measurements were highly correlated (r=0.94, P<0.0001). Conclusions: Introduction of computed tomography-guided angiographic image acquisition has significantly improved the analyz-ability of the angiographic VD assessment of post-TAVI AR.