New insights into the progression of aortic stenosis: implications for secondary prevention.

To the Editor: Palta et al1 suggest new insights into the progression of aortic stenosis. They report a series of 170 patients with “any degree” of aortic stenosis who underwent 2 echocardiograms >3 months apart. It is not indicated what proportion of patients with aortic stenosis were not included because they underwent only 1 examination. The selection criteria in this retrospective study may have introduced systematic and significant bias. Importantly, patients with severe or even moderate aortic stenosis may have been excluded because the initial severity or subsequent progression of the disease would have culminated in surgical correction or death before a second study was obtained. Consistent with this observation, the degree of aortic stenosis in patients in the study was mild (mean valve area, 1.17 …