Impact of Flow-Gradient Patterns on Outcomes of Transcatheter Aortic Valve Replacement for Severe Aortic Stenosis with Preserved Left Ventricular Ejection Fraction.

Abstract

To compare the clinical outcomes of transcatheter aortic valve replacement (TAVR) in patients with severe aortic stenosis (AS) and preserved ejection fraction (pEF) according to flow-gradient status.This retrospective study focused on patients with severe AS and pEF (≥ 50%) undergoing TAVR with newer generation valves (Sapien3/3 Ultra, Evolut Pro/Pro+/FX) between 2018 and 2022 (n = 781). Patients were divided into 3 groups: normal-flow high-gradient (NF-HG, stroke volume index ≥ 35 mL/m² and mean pressure gradient ≥ 40 mmHg or peak velocity ≥ 4 m/second), low-flow high-gradient (LF-HG), and paradoxical low-flow low-gradient (pLF-LG) groups. Multivariable Cox regression hazard model was used to adjust for confounders.There were 525, 188, and 68 patients in the NF-HG, LF-HG, and pLF-LG groups, respectively. For the entire cohort, the median age was 82 years, and the periprocedural, 1-year, and 5-year mortality rates were 1.8%, 12%, and 48%, respectively. During a median follow-up period of 25 (range 0-72) months, the rates of all-cause mortality and the composite of all-cause mortality and rehospitalization for heart failure were significantly higher in the LF-HG group compared with the NF-HG group, with adjusted hazard ratios (HRs) of 1.41 (95% confidence interval: 1.02-1.92) and 1.35 (1.01-1.79), respectively. In contrast, there were no significant differences between the LF-NG and pLF-LG groups.In patients undergoing TAVR for severe AS and pEF, LF-HG AS had a higher risk of all-cause mortality and the composite outcome compared with NF-HG AS.