Pressure-recovery adjustment of aortic valve area does not improve risk prediction in aortic stenosis

Abstract

Abstract Background In aortic stenosis (AS), overestimation of pressure gradients by Doppler compared to catheter-based measurement can be adjusted for by accounting for the pressure-recovery, expressed as an energy-loss index (ELI). However, evidence of improved risk assessment by ELI instead of aortic valve area indexed by body-surface area (AVAi) is scarce. Purpose We aimed to evaluate the prognostic performance of ELI and AVAi in a head-to-head comparison using large-scale, real-world data. Methods In the multi-center, mortality-data linked National Echocardiography Database of Australia (NEDA), patients with AS and requisite aortic area measurements were identified. The prognostic value of AVAi and ELI, respectively, was analyzed using Cox regression and compared by difference in C statistics. Results In patients with mild AS (n=3,179), moderate AS (n=4,194), and severe AS (n=3,120), there were 4,229 deaths of which 2,359 were cardiovascular deaths (median [interquartile range] follow-up 2.5 [1.1–4.5] years). There was an association with increased mortality risk per 0.1 cm2/m2 decrement for both AVAi (hazard ratio CV mortality [95% confidence interval] 1.18 [1.16–1.20]) and ELI (1.10 [1.09–1.12]). Prognostic performance for 5-year CV mortality did not improve by using ELI compared to AVAi (C statistic 0.626 vs 0.626, p=0.96). Conclusions In aortic stenosis, ELI was not associated with improved prognostic performance compared to AVAi using large-scale, real-world clinical data. These data do not support routine calculation of pressure recovery in echocardiographic reporting. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Swedish Heart and Lung Foundationthe Swedish Cardiac Society