Valve Hemodynamics Following Transcatheter or Surgical Aortic Valve Replacement in Patients With Small Aortic Annulus

This study aimed to compare the hemodynamic performance of transcatheter and surgical aortic valves in patients with severe symptomatic aortic stenosis and small aortic annulus (SAA) and to determine the valve hemodynamics according to transcatheter valve type. Consecutive surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) patients with SAA were case-matched (1:1) on the basis of sex, body surface area, aortic annulus diameter, and left ventricular ejection fraction. A total of 357 patients in each group constituted the final study population. A second match on the basis of aortic annulus diameter and valve/annulus calcium burden was performed within the TAVR group to compare the valve performance between balloon- (n = 52) and self-expanding (n = 52) transcatheter valve systems (BEV, SEV). The echocardiograms performed at hospital discharge were used for evaluating valve hemodynamics. The mean annulus diameter of the study population was 19.2 ± 0.3 mm. The TAVR group (vs SAVR) exhibited lower mean gradient (12 ± 7 mm Hg vs 15 ± 6 mm Hg, p <0.001), larger effective orifice area (1.46 ± 0.39 cm² vs 1.25 ± 0.37 cm², p <0.001) and a lower rate of severe prosthesis-patient mismatch (PPM) (14% vs 24%, p = 0.001). Moderate-severe AR was present in 2.5% of the TAVR recipients versus none patient in the SAVR group. There were no differences in valve hemodynamics between balloon-expanding transcatheter valve system and self-expanding transcatheter valve system, and similar rates of severe PPM were observed in both groups (p = 0.488). In conclusion, TAVR presented superior valve hemodynamics and lower incidence of severe PPM compared with SAVR in SAA patients. Similar valve performance results were observed between transcatheter valve types.