Clinical features and prognosis of patients with isolated severe aortic stenosis and valve area less than 1.0 cm²

Objective Current guidelines define severe aortic stenosis (AS) as an aortic valve area (AVA)≤1.0 cm 2 , but some authors have suggested that the AVA cut-off be decreased to 0.8 cm 2 . The aim of this study was, therefore, to better describe the clinical features and prognosis of patients with an AVA of 0.8–0.99 cm 2 . Methods Patients with isolated, severe AS and ejection fraction ≥55% with an AVA of 0.8–0.99 cm 2 (n=105) were compared with those with an AVA<0.8 cm 2 (n=155) and 1.0–1.3 cm 2 (n=81). The endpoint of this study was a combination of death from any cause or aortic valve replacement at or before 3 years. Results Patients with an AVA of 0.8–0.99 cm 2 group comprised predominantly normal-flow, low-gradient (NFLG) AS, while high gradients and low flow were more often observed with an AVA<0.8 cm 2 . The frequency of symptoms was not significantly different between an AVA of 0.8–0.99 cm 2 and 1.0–1.3 cm 2 . The combined endpoint was achieved in 71%, 52% and 21% of patients with an AVA of 0.8 cm 2 , 0.8–0.99 cm 2 and 1.0–1.3 cm 2 , respectively (p<0.001). Among patients with an AVA of 0.8–0.99 cm 2 , NFLG AS was associated with a lower hazard (HR=0.40, 95% CI 0.23 to 0.68, p=0.001) of achieving the combined endpoint with outcomes similar to moderate AS in the first 1.5 years of follow-up. Patients with high-gradient or low-flow AS with an AVA of 0.8–0.99 cm 2 had outcomes similar to those with an AVA<0.8 cm 2 . The sensitivity for the combined endpoint was 61% for an AVA cut-off of 0.8 cm 2 and 91% for a cut-off of 1.0 cm 2 . Conclusions The outcomes of patients with AS with an AVA of 0.8–0.99 cm 2 are variable and are more precisely defined by flow-gradient status. Our findings support the current AVA cut-off of 1.0 cm 2 .