Surgical and transcatheter aortic valve procedures. The limits of risk scores

Transcatheter aortic valve implantation (TAVI) is an alternative to surgicalaortic valve replacement in very high-risk patients with severe aortic stenosis. The present multicenter, retrospective study investigates the accuracy andcalibration properties of the EuroSCORE and the age, serum creatinine, andejection fraction (ACEF) score in selecting a population of patients to bereferred to TAVI. The study includes 1053 surgical and 211 transcatheterprocedures. The operative mortality rate within the surgical group was 2%. TheEuroSCORE and the ACEF score had similar levels of accuracy; the ACEF score waswell calibrated and the EuroSCORE overestimated the mortality risk. The observed mortality rate within the transcatheter group was 10.4%. Cut-off valuescorresponding to a mortality rate of 10% were 26 for the logistic EuroSCORE and2.5 for the ACEF score: both the EuroSCORE and the ACEF score may be used torefer patients to TAVI. However, they do not consider a number of 'extreme' risk conditions that may justify a transcatheter procedure even in absence of anoverall elevated risk score. These risk conditions should be included in aspecific risk model for referring patients for TAVI.