Abstract Body (Do not enter title and authors here): Introduction:
Self-expanding transcatheter aortic valves (SEV) have reportedly better hemodynamic outcomes, and similar clinical outcomes compared to balloon-expanding valves (BEV) at 1 year in patients with a small aortic annulus based on results from the SMART trial. Head-to-head comparison of long-term clinical outcomes, however, is lacking.

Objectives: To compare the long-term (5 years) echocardiographic and cardiovascular outcomes in BEV versus SEV in patients with small aortic annulus undergoing transcatheter aortic valve replacement (TAVR).

Methodology:
The RESOLVE registry included consecutive patients who underwent TAVR and survived up to 30 days at Cedars-Sinai Medical Center with either BEV or SEV from 2015 to 2020, with clinical variables obtained from the STS/TVT registry. CT core lab analysis identified patients with a small aortic annulus (<430 mm²), who were systematically followed up with clinical exams and echocardiography until December 2023. The primary outcome was a composite of all-cause mortality, stroke or transient ischemic attack, or heart failure hospitalization at 5 years.

Results:
Out of 1392 patients, a total of 423 met criteria for small aortic annulus (345 BEV, 78 SEV), with a median follow-up of 5 years (4-6 years). There were no significant differences in baseline sociodemographic and clinical characteristics between the BEV and SEV groups. (Figure 1) The post-TAVR invasive aortic valve mean gradient were similar in both groups [Median (IQR): BEV:3(1-5.8), SEV: 3.4(0.4-6.6), p 0.58], while echocardiographic gradients were higher in BEV group [Median (IQR): BEV:12 (9-15), SEV:8(6-11), p<0.001)].There was no significant difference in primary outcome at 5 years in Cox multivariable regression analysis (HR:1.21, 95% CI 0.81-1.82, p 0.33) (Figure 2). There were no significant differences in other clinical endpoints at 5 years, although patients with SEV had lower echocardiographic gradients and higher indexed effective orifice area. (Figure 2-3)

Conclusion:
Post-TAVR invasive aortic valve gradients were similar between BEV and SEV, despite higher echocardiographic transaortic gradients in BEV patients. We found no significant difference in 5-year clinical outcomes between patients who received TAVR with BEV or SEV.