Abstract 4144724: Native aortic stenosis progression: a focus on sex differences.

Background: Paucity of evidence is available on sex-differences in the progression, left ventricular (LV) remodelling and long-term outcome in patients with native mild-to-moderate aortic stenosis (AS) and preserved LV ejection fraction (LVEF). Objectives: To assess the sex-differences in the progression, LV remodelling and long-term outcome of native AS. Methods: Baseline and follow-up echocardiographic data of patients with at least mild-to-moderate AS [aortic valve area(AVA)≤1.5 cm2, maximum aortic velocity(Vmax) ≥2.5 m/s or mean gradient(MG)≥25 mmHg] were prospectively collected between 2014 and 2019 and retrospectively analysed. Patients with LVEF<50%, or mitral or aortic regurgitation >mild were excluded. AS progression (analysed by annualized progression ratios in echocardiographic parameters), all-cause death, aortic valve replacement (AVR), were investigated stratifying for sex. Results: We included 677 patients with a mean age of 70.8±13.2 years, 258 (38.1%) women. During a median 5 years follow-up, 118(17.4%) deaths and 211(32.2%) AVR occurred. After inverse-propensity-weighting (IPW), men had faster progression rate of AS compared to women (MG: mean difference 1.77[1.10-2.43] mmHg/year, p<0.0001; and Vmax: mean difference 9.56[5.7-13.4] cm/s/year, p<0.0001). While women had higher annualized progression ratio in LV mass-indexed (mean difference 2.51[4.56-0.45] mg/m 2 /year, p=0.017), relative wall thickness (mean difference 0.007[0.01-0.003], p=0.039), but lower stroke-volume-indexed (SVi) (mean difference 0.80[1.10-2.43]ml/m 2 /year, p=0.012). Similar results were obtained after 1:1 matching. Relative to women, men presented similar incidence of all-cause mortality (HR 1.07[0.72-1.56], p=0.73) and AVR on competitive risk analysis (IPW-Sub Hazard Ratio SHR 0.93 [0.61-1.41], p=0.74). Conclusions: Mild-to-moderate AS in men presented accentuated hemodynamic progression over time; however, women were more likely to develop LV hypertrophic/concentric remodelling accompanied by lower flow. Similar long-term outcomes were observed in men and women. These results emphasize the importance of evaluating LV remodelling and flow pattern in AS, and not only the AS severity. The slower hemodynamic progression of AS observed in women may be linked to their tendency in reducing SVi, due to distinct LV remodelling pattern.