Abstract 15087: Impact of Assessment for Aortic Annulus Through Cardiac Cycle by Using Four-dimension Multidetector Computed Tomography in Patients With Severe Aortic Stenosis

It was known that correct assessment of aortic annulus diameter and degree of aortic valve calcification (AVC) before transcatheter aortic valve implantation (TAVI) by using multidetector computed tomography (MDCT) is important to minimize complications such as annulus rupture, coronary obstruction, prosthesis migration and para-valvular aortic regurgitation (AR). However, change of annulus diameter during cardiac cycle remains fully determined. Recently, it was reported that new technique of measuring variability of the interesting area through a cardiac cycle by using voxel tracking method for image data obtained four-dimensional MDCT (4D-MDCT) was developed. In the present study, we examined whether annulus change through a cardiac cycle can be evaluated, and aortic annulus variability (AAV) related to severity of aortic stenosis (AS) and occurrence of AR immediately after TAVI procedure. We performed 4D-MDCT in 90 patients with severe AS (mean age, 80 years; mean AVA, 0.57 cm2) and 10 normal subjects without cardiac structure disease (NP). Image data of 4D-MDCT were analyzed offline on a work station using voxel tracking method (Ziosoft Inc.). AAV was defined standard deviation of annulus diameter through a cardiac cycle indexed by mean annulus diameter. AVC was visually graded. Cardiac phase at max annulus diameter was significantly delayed in patients with AS compared with NP (R-R%, 13 ± 10 vs. 3 ± 3 %, P In conclusion, it was demonstrated that aortic annulus was changed through the cardiac cycle. Aortic valve assessment evaluated by 4D-MDCT may provide more detail information for preoperative planning of TAVI.