Impact of Aortic Annulus Size on Clinical and Hemodynamic Outcomes of Transcatheter Aortic Valve Implantation With the Navitor Valve.

Background

Patients with small aortic annuli undergoing transcatheter aortic valve implantation (TAVI) are at risk of higher residual transvalvular gradients. Evidence on the performance of new-generation intra-annular self-expanding valves in this anatomical setting remains limited.

Aims

To evaluate the impact of annular size on procedural, hemodynamic, and mid-term clinical outcomes after TAVI with the Navitor valve.

Methods

Patients were stratified by annular area measured by multi-slice computed tomography, defining a small annulus as ≤ 430 mm2. Primary endpoints at 12 months were: (i) a clinical composite of all-cause death, disabling stroke, or heart failure rehospitalization, and (ii) a composite endpoint of bioprosthetic valve dysfunction. Secondary endpoints included VARC-3-defined procedural and early outcomes and valve hemodynamic performance.

Results

The study population comprised 218 patients, of whom 91 (41.7%) had a small annulus. VARC-3 technical success was high and comparable between small and non-small annuli (96.7% vs. 96.1%). Patients with small annuli had higher early post-procedural mean transvalvular gradients (7.7 ± 3.8 vs. 6.6 ± 3.0 mmHg; p = 0.029) and smaller effective orifice areas index (1.1 ± 0.3 vs. 1.3 ± 0.2 cm2/m2; p = 0.037), while the incidence of mean gradients ≥ 20 mmHg remained low (1.1% vs. 0.0%; p = 0.432). At 12 months, the clinical composite endpoint occurred in 8.8% of patients with small annuli and 10.2% with non-small annuli (p = 0.759). Bioprosthetic valve dysfunction was infrequent and similar between groups (6.6% vs. 6.3%; p = 0.875).

Conclusions

TAVI with the Navitor intra-annular self-expanding valve was associated with high procedural success, favorable valve hemodynamics, and comparable mid-term clinical outcomes irrespective of annular size.