Assessment of aortic stenosis severity: when the gradient does not fit with the valve area: Figure 1

In this issue of Heart , Minners et al 1 ( see page 1463 ) provide an extension of their previous work2 where they retrospectively analysed the data of their Doppler-echocardiography laboratory and reported that there is a discrepancy in the criteria of aortic valve area (AVA; 40 mm Hg) proposed in the guidelines to define severe aortic stenosis (AS).2 In the present study1 they present data obtained by cardiac catheterisation in a subset of the previous series.2 The main findings of this study are: (1) when using the framework of the current guidelines, inconsistent grading of AS (ie, AVA <1.0 cm2 but gradient ≤40 mm Hg) occurred in 36% of patients with preserved left ventricular (LV) systolic function (LV ejection fraction (LVEF) ≥50%), and this proportion was similar irrespective of the method used to assess stenosis severity (ie, Doppler-echocardiography vs cardiac catheterisation); and (2) the proportion of patients with reduced stroke volume (stroke volume index ≤35 ml/m2) despite apparently normal LV systolic function was substantially higher in the subset of patients with inconsistent grading (52%) than in those with consistent grading (29%). This latter finding lends further support to the concept that discordance between AVA and gradient is often due to paradoxical low-flow AS, a disease pattern recently described by our group.3 We indeed reported that an important proportion of patients with severe AS may paradoxically have a low flow and thus often a low gradient, despite the presence of normal LVEF.3 When compared with patients with normal LV outflow, patients with paradoxical low flow are characterised by a higher prevalence of women and concomitant hypertension, older age, a higher degree of LV concentric remodelling, impaired LV filling, smaller end-diastolic volume and reduced mid-wall and longitudinal shortening. These patients also have markedly increased global …