Investigators of the TOPAS study (True Or Pseudo severe Aortic Stenosis) identified the major determinants of survival, functional status, and change in left ventricular fraction ejection during follow-up of patients (n=101) with low-flow, low-gradient aortic stenosis. They found that the most significant predictors of mortality were impaired functional capacity according to the Duke Activity Status Index (p=0.0005) or 6-minute walk test distance (p<0.0001 in the subset of 72 patients), more severe valve stenosis (p=0.03), and reduced peak stress left ventricular ejection fraction (p=0.03). The Duke Activity Status Index, 6-minute walk test distance, and left ventricular ejection fraction improved only in the subgroup of patients having had aortic valve replacement during follow-up. The results should help clinicians in the evaluation of operative risk and in therapeutic management of patients with aortic stenosis.