The European System for Cardiac Operative Risk Evaluation (EuroSCORE) is not appropriate for withholding surgery in high-risk patients with aortic stenosis: a retrospective cohort study.
BACKGROUND
The European System for Cardiac Operative Risk Evaluation (EuroSCORE) is a widely used risk assessment tool in patients with severe aortic stenosis to determine operability and to select patients for alternative therapies such as transcatheter aortic valve implantation. The objective of this study was to determine the accuracy of the EuroSCORE in predicting mortality following aortic valve replacement (AVR).


METHODS
The logistic EuroSCORE was determined for all consecutive patients that underwent conventional AVR between 1995 and 2005 at our institution. Provincial Vital Statistics were used to determine all-cause mortality. The accuracy of the prognostic risk prediction provided by logistic EuroSCORE was assessed by comparing observed and expected operative mortality.


RESULTS
During the study period, a total of 1,421 patients underwent AVR including 237 patients (16.7%) that had a logistic EuroSCORE > 20. Among these patients, the mean predicted operative mortality was 38.7% (SD = 18.1). The actual mortality of these patients was significantly lower than that predicted by EuroSCORE (11.4% vs. 38.7%, observed/expected ratio 0.29, 95% CI 0.15-0.52, P < 0.05). The EuroSCORE overestimated mortality within all strata of predicted risk. Although medium-term mortality is significantly higher among patients with EuroSCORE > 20 (log rank P = 0.0001), approximately 60% are alive at five years.


CONCLUSIONS
Actual operative mortality in patients undergoing AVR is significantly lower than that predicted by the logistic EuroSCORE. Additionally, medium-term survival following AVR is acceptable in high-risk patients with EuroSCORE > 20. More accurate risk prediction models are needed for risk-stratifying patients with severe aortic stenosis.
Kalavrouziotis
Dimitri
D
Department of Surgery, Division of Cardiac Surgery, Queen Elizabeth II Health Sciences Centre, Dalhousie University, 1796 Summer Street, room 2269, Halifax, Nova Scotia, B3H 3A7, Canada. dkalavro@dal.ca
Li
Debbie
D
Buth
Karen J
KJ
Légaré
Jean-Francois
JF
D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000473:pathology / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000175:diagnosis* / Q000401:mortality / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D012720:Severity of Illness Index