Bioprosthetic Valve Performance After Transcatheter Aortic Valve Replacement With Self-Expanding Versus Balloon-Expandable Valves in Large Versus Small Aortic Valve Annuli: Insights From the CHOICE Trial and the CHOICE-Extend Registry.

OBJECTIVES: The aim of this study was to compare self-expanding and balloon-expandable transcatheter heart valves (THVs) in large versus small aortic valve annuli.

BACKGROUND: The degree of THV oversizing varies according to annular size, and this can modify the hemodynamic performance of self-expanding and balloon-expandable THVs.

METHODS: Patients undergoing transcatheter aortic valve replacement in the randomized CHOICE (Comparison of Transcatheter Heart Valves in High Risk Patients With Severe Aortic Stenosis: Medtronic CoreValve vs Edwards SAPIEN XT) trial (CoreValve [CV], n = 120; SAPIEN XT [SXT], n = 121) and the nonrandomized CHOICE-Extend registry (Evolut R [ER], n = 100; SAPIEN 3 [S3], n = 334) were compared for THV performance by echocardiography (in all patients) and by cardiac magnetic resonance imaging (MRI) regurgitant fraction (RF) (in a subgroup of patients). Patients were stratified according to aortic valve annular mean diameter into those with large (>23 mm) or small (≤23 mm) annuli.

RESULTS: THV percentage oversizing was 19.1 ± 6.4% with the CV, 11.4 ± 7.0% with the SXT, 18.8 ± 4.8% with the ER, and 3.7 ± 5.5% with the S3. Transvalvular mean pressure gradient was lower with the CV and ER than with the SXT and S3 in both the large and small annulus groups. In the randomized CHOICE trial, moderate to severe prosthetic valve regurgitation (PVR) was more with the CV than the SXT in large annuli (15.1% vs. 0.0%; p = 0.002; MRI RF: 10.5 ± 10.2% vs. 4.4 ± 4.5%; p = 0.036) but not in small annuli (0.0% vs. 5.7%; p = 0.50; MRI RF: 4.0 ± 4.1% vs. 4.0 ± 3.4%; p = 0.98). In the CHOICE-Extend registry, moderate to severe PVR occurred in 2 patients, and any PVR was not significantly different between the ER and the S3 in large (41.7% vs. 32.5%; p = 0.24) or small (47.1% vs. 43.8%; p = 0.84) annuli. MRI RF was not different in large annuli (5.0 ± 3.8% vs. 5.0 ± 6.1%; p = 0.99) but was significantly lower with the ER than the S3 in small annuli (2.9 ± 2.3% vs. 4.8 ± 3.7%; p = 0.023). On multivariate analysis, transcatheter aortic valve replacement with the ER in small annuli was associated with a lower rate of prosthesis-patient mismatch than with the S3, with no increased risk for PVR.

CONCLUSIONS: Older-generation balloon-expandable THVs were associated with less PVR than self-expanding THVs in patients with large but not small annuli. The next-generation self-expanding THV has improved sealing in patients with large annuli and may have potential advantages in patients with small annuli.