Fully independent external validation of the Transcatheter Aortic Valve Replacement 30-day (TAVR-30) hospital readmission model

Early and late readmissions after Transcatheter Aortic Valve Replacement (TAVR) are common and associated with worse outcome. A risk prediction model (TAVR-30) was recently developed using readily available clinical variables to identify patients at risk for hospital readmission within 30 days after TAVR. We performed an independent external validation of the TAVR-30 model.The Swedish TAVR-registry, linked together with other mandatory national registries was used to identify all TAVR procedures, variables from the original model, hospitalizations and deaths between the years 2008 to 2021.A total of 8459 patients underwent TAVR, 7693 patients had complete data and were included in the analysis. Out of these, 928 patients experienced a readmission within 30 days. Using the estimates from the original model, a concordance (c)-index of 0.51, a calibration slope of 0.07 and intercept of -0.62 were obtained respectively, overall implying poor model performance.This independent external validation indicates poor performance of the TAVR-30 model in a Swedish setting. Further research is needed to develop more reliable tools for predicting the risk of early hospital readmission after TAVR, as well as, for providing a deeper understanding of how to develop risk models that performs well in patients with multiple underlying comorbidities.