Impact of Annulus Size on Bioprosthetic Valve Failure after Self-Expanding Transcatheter Heart Valves Replacement

There is limited evidence on the prognosis and long-term valve durability after transcatheter aortic valve replacement (TAVR) in patients with small aortic annulus (SAA) and large aortic annulus (LAA). This analysis was sought to evaluate the impact of annular size differences on patients' and valve outcomes. A total of 1,211 patients undergoing TAVR using self-expandable transcatheter heart valve (SE-THV) were retrospectively analyzed. The cut-off for SAA was defined as annulus perimeter of < 72 mm. The primary endpoints were all-cause mortality and bioprosthetic valve failure (BVF) between the SAA and LAA groups. As a sub-analysis, the impact of postprocedural mean pressure gradient (mPG) ≥ 20mmHg and severe prosthesis-patient mismatch (PPM) on these outcomes were also evaluated. Of all patients, 60.1% (n = 723) had SAA. At 7 years after TAVR, the SAA group had lower incidence of all-cause mortality (53.7% vs 63.7%, log-rank p = 0.05) and lower event rate of BVF than LAA (1.2% vs 4.6%, p = 0.01 for Gray's test). Multivariate Cox-regression and Fine-Gray competing risk regression analysis demonstrated the presence of SAA was related to better prognosis (Hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.67 to 0.98) and lower BVF (adjusted subdistribution HR, 0.41; 95% CI, 0.17 to 0.98). There were no impact of postprocedural mPG ≥ 20 mmHg or severe PPM on the difference of mortality and BVF. Further, these results were consistent in the patients with SAAs. In conclusion, SAA had better long-term patients' prognosis and valve durability after TAVR with SE-THV.