BackgroundFrailty is a geriatric syndrome that can influence mortality and functional recovery after treatment of severe aortic stenosis (AS). The integration of standardized geriatric assessment (GA) in clinical practice is limited by a lack of consensus on how to measure it.ObjectivesThis study aims to compare the incremental predictive value of different frailty scales to predict the outcomes following surgical aortic valve replacement, transcatheter aortic valve implantation, and conservative treatment of severe AS.MethodsA prospective cohort of 300 older adults with severe AS will be assembled after standard clinical examinations and a comprehensive GA, including 18 different tests and values. Primary outcome parameters are overall mortality, cardiovascular mortality, quality of life, and functionality. Secondary parameters are overall complications, cardiovascular complications, and costs.ResultsExpected results will contribute to the growing body of evidence on frailty based on parameters that influence clinical and functional outcome in elderly patients independent of the method of treatment. The pre-procedural assessment is expected to be valuable in discriminating new post-procedural complications from simple exacerbations of pre-existing conditions. Therefore, a new frailty test which is simple and feasible for application in a clinical routine by most medical professionals, may help in identifying patients for whom further GA should be considered. Finally, such a frailty score could support heart teams to find the right treatment for patients suffering from AS.ConclusionComparison of different frailty scales has not only the goal of finding a predictive value of mortality but also to bring in a meaningful improvement for each individual patient and to avoid disability or fatal outcomes.