Calcification in aortic stenosis

There is growing evidence that the degree of calcification of the aortic valve (AV) is prognostically significant, independent of the degree of imposed haemodynamic load.

The concept that aortic valve calcification (AVC) is an active biological process and that AVC load provides information incremental to haemodynamic measures of aortic stenosis (AS) severity is not completely intuitive, as the haemodynamic load has been considered the ultimate cause of death. Furthermore, calcification is a non-linear process that increases exponentially1 and accelerates disease progression.

However, calcification by echocardiography has been diagnosed on the basis of video qualitative assessment, which grossly correlates with AVC quantified by CT but with wide overlap between echo ‘calcification’ grades.1 Until now, the imprecise AV ‘calcium’ scoring on echocardiography may have impaired the detection of crucial differences between men and women in relatively small observational cohorts. In recent years, multidetector CT, taking advantage of the unequalled value of X-ray calcium assessment, provided definitions of sex-specific severe AVC load in relation to haemodynamic AS severity, with lower thresholds in women.2 3 Previous studies with CT1 linked valve calcification to cardiovascular events following diagnosis, dominated by performance AVAi, and the pitfalls of this endpoint may explain why this measure has not yet gained wide acceptance. Furthermore, different thresholds were used, no sex-specific threshold was defined, and due to the strong association between AVC and valve haemodynamic data, the incremental value of AVC remained unclear.

In their Heart manuscript, Thomassen et al 4 demonstrated that AVC in AS scored by echocardiography has sex-specific risk factors, and that the presence of moderate to …