redo-TAVRにおけるCT画像を用いた術前シミュレーション

Transcatheter aortic valve (TAV) failure may require redo transcatheter aortic valve replacement (redo-TAVR). The multiple layers of metal after redo-TAVR may jeopardize coronary artery patency and accessibility and result in prosthesis-patient mismatch. Dedicated software may use multi-slice computed tomography (MSCT) imaging to simulate TAV deployment relative to the prior TAV and the individual's anatomy and predict coronary accessibility and TAV expansion.

We aimed to validate redo-TAVR simulations created in FEops HEARTguide.

This multicenter observational study included redo-TAVR patients who had MSCT imaging available at baseline, after index-TAVR and after redo-TAVR. Patient-specific redo-TAVR simulations were created. Simulated valve-to-aorta distances (a proxy for coronary accessibility), neoskirt height, TAV expansion at multiple frame levels, and residual valve area after redo-TAVR were compared to follow-up MSCT.

Among 25 patients, HEARTguide simulations of valve-to-coronary (VTC) distance (left VTC 6.0 ± 2.2 vs. 6.4 ± 2.3 mm, ICC = 0.856, p < 0.001; right VTC 5.8 ± 1.9 vs. 5.6 ± 1.9 mm, ICC = 0.740, p < 0.001) showed good agreement while valve-to-sinotubular-junction (VTSTJ) distance showed moderate agreement with follow-up MSCT (left VTSTJ 2.5 ± 1.8 vs. 3.3 ± 1.8 mm, ICC = 0.614, p = 0.004; right VTSTJ 2.8 ± 1.8 vs. 2.9 ± 1.2 mm, ICC = 0.613, p = 0.003). Redo-TAVR frame expansion simulations (mean frame area 434.8 ± 141.6 vs. 401.6 ± 142.9 mm, ICC = 0.930, p < 0.001; 393.5 ± 63.2 vs. 383.1 ± 82.5 mm, ICC = 0.822, p < 0.001, respectively) and simulations of residual valve area after redo-TAVR showed good agreement for self-expanding and balloon-expandable TAV (407.8 ± 67.8 vs. 389.6 ± 50.4 mm, ICC = 0.837, p < 0.001; 358.0 ± 66.1 vs. 336.1 ± 79.9 mm, ICC = 0.823, p < 0.001).

In this pilot study, MSCT-derived simulations of redo-TAVR provided accurate insights into coronary accessibility, TAV expansion, and residual valve area.