Impact of aortic landing zone geometry on TAVI implantation depth: comparison between ACURATE neo2 and Portico/Evolut.

Background: During transcatheter aortic valve implantation (TAVI), increased aortic angulation can affect the final implantation depth of self-expandable (SE) devices due to the interaction between the high stent frame and the targeted aortic landing zone (LZ). We herein sought to investigate the behaviour of the ACURATE neo2, a SE device with a unique release mechanism, in relation to patient-specific angulation and curvature of the aortic LZ.

Methods: The mismatch between the intended and the final implantation depth (∆H) was compared between patients treated with ACURATE neo2 (Acurate, n=106) and Evolut/Portico (n=101) SE devices. To do so, curvature (κ LZ,tot ) and angulation (αLZ,Dist ) were calculated based on the three-dimensional aortic LZ centerline available from pre-TAVI CT.

Results: The Acurate and Evolut/Portico groups showed a negligible difference (p=0.09) for ∆H averaged between non-coronary (NCC) and left coronary cusp (LCC). However, when splitting both ∆HNCC and ∆HLCC values into two subgroups based on κ LZ,tot and αLZ,Dist median values, ∆H significantly increased on LCC compared with NCC in Evolut/Portico patients with high LZ curvature (κLZ,tot >0.123/mm, p=0.016) and high LZ distal angulation (αLZ,Dist >28.5°, p=0.012). No statistically significant differences arose within the Acurate group.

Conclusions: Among SE devices, the ACURATE neo2 was the least affected by the curvature and angulation of the LZ anatomy, leading to a more predictable and symmetrical implantation depth. The clinical impact of this finding on TAVI outcomes in patients with an angulated aortic LZ warrants further investigation in larger studies.