• aortic stenosis

Echocardiography is the key diagnostic modality for the assessment of aortic stenosis (AS) with a number of parameters available to estimate stenosis severity. Morphological criteria including calcification and reduced leaflet mobility are supplemented by flow dependent (jet velocity and mean pressure gradient) and largely flow-independent parameters (aortic valve area, aortic valve area index and velocity ratio).1 2 In the majority of patients, consistent results regarding stenosis severity will be obtained over the range of parameters. However, depending on the population under study, up to 30% of patients will demonstrate discrepant stenosis severity between flow-dependent (eg, mean pressure gradient) and flow-independent (aortic valve area) markers, with the latter commonly indicating a higher grade stenosis.3

Two developments over the last decades have augmented the problem of discrepant stenosis severity. First, there has been a trend in guidelines towards easing the partition values for the assessment of AS severity with an emphasis on aortic valve area .1 2 The threshold for severe stenosis according to mean pressure gradient moved from 50 mm Hg to 40 mm Hg and according to aortic valve area from <0.8 cm² to <1 cm² (with an often unrecognised twitch from <1 to ≤1 cm …