ObjectiveNew echocardiographic definitions have been proposed for hemodynamic structural valve deterioration. We aimed to study their consistency in classifying structural valve deterioration after surgical aortic valve replacement. MethodsData were used of patients undergoing surgical aortic valve replacement in a multicenter, prospective cohort study with a 5-year follow-up. All patients received the same stented bioprosthesis. Echocardiographic parameters were assessed by an independent core laboratory. Moderate or greater stenotic hemodynamic structural valve deterioration was defined according to Capodanno and colleagues, Dvir and colleagues, and the Valve Academic Research Consortium 3; regurgitation data were not considered in this analysis. Consistency was quantified on the basis of structural valve deterioration classification at subsequent time points. ResultsA total of 1118 patients received implants. Patients’ mean age was 70 years, and 75% were male. Hemodynamic structural valve deterioration at any visit was present in 51 patients (4.6%), 32 patients (2.9%), and 34 patients (3.0%) according to Capodanno, Dvir, and Valve Academic Research Consortium 3. A total of 1064 patients (95%) were never labeled with structural valve deterioration by any definition. After the first classification with structural valve deterioration, 59%, 59%, and 65% had no subsequent structural valve deterioration classification according to Capodanno, Dvir, and Valve Academic Research Consortium 3, respectively. ConclusionsThe current definitions of hemodynamic structural valve deterioration are strong negative predictors but inconsistent positive discriminators for the detection of stenotic hemodynamic structural valve deterioration. Although the diagnosis of structural valve deterioration may be categorical, echocardiographic indices lack this degree of precision in the first 5 years after surgical aortic valve replacement. The inconsistency of current structural valve deterioration definitions impedes the detection of true valve degeneration, which challenges the clinical usefulness of these definitions.