Surgical risk scores applied to transcatheter aortic valve implantation: Friends or foes? short-term and long-term outcomes from a single-center registry

Background. Transcatheter aortic valve implantation (TAVI) is a valid alternative to surgical aortic valve replacement for the treatment of symptomatic aortic stenosis. The EuroScore (ES) II, logistic EuroScore (log ES), and the Society of Thoracic Surgeons (STS) score are the most applied scores for surgical risk stratification. However, their predictive value for patients undergoing TAVI is still unclear. Aim. To evaluate the performance of STS, log ES and ES II as predictors of short-term and long-term mortality in patients undergoing TAVI. Methods. Between February 2008 and October 2017, a total of 384 patients underwent transfemoral TAVI at our institution and constituted the study population. Patients were divided into three groups based on the class of risk (low, intermediate, and high) calculated by each score. In-hospital complications, 30-day outcomes, and 5-year outcomes were assessed. Results. In-hospital mortality rate was 2.6% (n = 10). All scores over-estimated the risk of 30-day mortality, especially for the highest risk classes. At the end of follow-up (5 years), STS risk stratification was able to stratify all-cause and cardiovascular (CV) mortality (P<.01 and P=.02, respectively). Patients with intermediate ES II risk showed a lower survival rate (P=.04) while CV deaths did not differ between classes of risk. All-cause mortality and CV mortality curves did not diverge according to the patients' risk profiles derived from log ES. Conclusion. Conventional surgical risk scores are not appropriate to predict 30-day mortality in patients undergoing transfemoral TAVI. STS assessment was the only risk score able to stratify long-term all-cause and CV mortality