Abstract
Objective: Transcatheter aortic valve implantation (TAVI) has become the standard treatment for older or high-risk surgical candidates with severe symptomatic aortic stenosis. However, reports on the mid-term outcomes of TAVI in patients with small annuli are limited. This study aimed to comprehensively evaluate the procedural success, hemodynamic performance, and midterm outcomes of TAVI using balloon-expandable transcatheter heart valves (BEVs) and self-expandable transcatheter heart valves (SEVs) in this population.
Methods: This single-center retrospective cohort study included 81 patients with an aortic valve annulus area <350 mm2 who underwent TAVI between July 2016 and March 2024. The patients were divided into BEV (N = 58) and SEV (N = 23) groups. The primary endpoint was all-cause mortality, and the secondary endpoints were adverse cardiovascular events and hemodynamic valve performance. Additionally, we compared clinical outcomes between patients with or without moderate or severe prosthesis–patient mismatch (PPM).
Results: Baseline characteristics showed that the SEV group was significantly shorter, lighter, and had a smaller body surface area (P <0.05). The procedural success rates were comparable between groups. The SEV group demonstrated superior hemodynamic performance, with larger indexed effective orifice areas (P <0.001) and lower mean pressure gradients (P <0.001). However, the BEV group had lower rates of paravalvular leakage ≥moderate and permanent pacemaker implantation. Moderate PPM was more frequent in the BEV group (P = 0.054), but no significant differences in all-cause mortality (P = 0.25), cardiovascular events (P = 0.12), or heart failure hospitalization (P = 0.28) were observed between patients with or without moderate or severe PPM. At five years, no significant differences in all-cause mortality and cardiovascular event-free survival were observed.
Conclusion: Both the BEV and SEV groups achieved favorable midterm outcomes in patients with small annuli. Although the SEV group showed superior hemodynamic performance, the BEV group showed fewer complications, such as paravalvular leakage. Despite a higher incidence of moderate PPM in the BEV group, no significant impact on clinical outcomes was observed. Individualized valve selection and long-term follow-up remain crucial for optimizing outcomes in this challenging population.
