New-Generation Transcatheter Valves for Extremely Small Aortic Annuli.

Background

Patients with extremely small aortic annuli are at increased risk of residual gradients and prosthesis-patient mismatch (PPM) after transcatheter aortic valve replacement (TAVR). Comparative data on contemporary valve platforms in this subset remain limited.

Objectives

The authors aimed to compare early clinical and hemodynamic outcomes among balloon-expandable valves (BEVs), supra-annular self-expanding valves (SA-SEVs), and intra-annular self-expanding valves (IA-SEVs) in patients with severe aortic stenosis and extremely small annuli.

Methods

Patients with annular area <314 mm2 from the OCEAN-TAVI registry were analyzed using multinomial propensity score overlap weighting. Primary outcomes were severe PPM, mean transvalvular pressure gradient ≥20 mm Hg, and paravalvular leakage (PVL) ≥mild.

Results

Among 385 patients, 125, 136, and 124 underwent BEV, SA-SEV, and IA-SEV implantation, respectively. Effective sample sizes after overlap weighting were 92.4, 93.6, and 85.4, with a median follow-up of 358 days. Adjusted probabilities of severe PPM were similarly low (1.6%, 2.0%, and 2.7%; P = 0.85). mean transvalvular pressure gradient ≥20 mm Hg occurred in 4.5%, 8.3%, and 2.3%, respectively (P = 0.19). PVL ≥mild was numerically more frequent with SEV than BEV (15.8%, 27.3%, and 27.0%; P = 0.09), with adjusted odds ratios versus BEV of 1.92 (95% CI: 0.96-3.84) for SA-SEV and 1.83 (95% CI: 0.91-3.70) for IA-SEV. Major complications and 1-year mortality were similar among groups.

Conclusions

Contemporary TAVR platforms showed broadly similar early outcomes, although PVL ≥mild was numerically more frequent with self-expanding valves.