Aortic stenosis (AS) is predominantly a degenerative valvular disease of the elderly, with a prevalence of 10–12.4% in those ≥75 years of age, severe in 3.4%.1 Population demographics clearly show Western populations to be are ageing, thereby further increasing the impact of AS. Among elderly patients with severe AS, 75% are symptomatic, 40% of whom are not treated surgically. No effective medical therapy is available for patients with AS, and if not treated by intervention, the estimated 5-year survival of severe AS is only 40% to 60%.2 Although symptoms remain the main indication for aortic valve replacement (AVR) in patients with AS, the interpretation of symptoms, particularly shortness of breath in the elderly, can be challenging.3 Therefore, accurate grading of AS severity and left ventricular (LV) function is crucial for a correct AVR indication.

Severe AS has been traditionally defined as an aortic valve area (AVA) <1 cm² with a mean systolic Doppler gradient ≥40 mm Hg or a peak aortic velocity ≥4 m/s. However, in clinical practice it is common for a patient to present only one or two of these criteria. It is well known that patients with severe AS may have a low gradient if their LV ejection fraction (LVEF) and cardiac output are decreased. Moreover, recent studies suggest that a significant proportion of patients with severe AS may paradoxically have a low transvalvular flow rate despite the presence of a preserved EF. This disease pattern may lead to underestimation of AS severity and thus inappropriate delay in AVR which may have a negative impact on patient outcome.

In this issue, Capoulade et al4 have assessed the usefulness of echocardiography to predict outcome in AS. This large study included 1065 consecutive patients with at least mild AS (V peak >2.0 m/s) without moderate–severe aortic regurgitation …