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.