The Impact of EuroSCORE II Risk Factors on Prediction of Long-Term Mortality.
BACKGROUND
The European System for Cardiac Operation Risk Evaluation (EuroSCORE) II has not been tested yet for predicting long-term mortality. This study was undertaken to evaluate the relationship between EuroSCORE II and long-term mortality and to develop a new algorithm based on EuroSCORE II factors to predict long-term survival after cardiac surgery.


METHODS
Complete data on 10,033 patients who underwent major cardiac surgery during a 7-year period were retrieved from three prospective institutional databases and linked with the Italian Tax Register Information System. Mortality at follow-up was analyzed with time-to-event analysis.


RESULTS
The Kaplan-Meier estimates of survival at 1 and 5 were, respectively, 95.0% ± 0.2% and 84.7% ± 0.4%. Both discrimination and calibration of EuroSCORE II decreased in the prediction of 1-year and 5-year mortality. Nonetheless, EuroSCORE II was confirmed to be an independent predictor of long-term mortality with a nonlinear trend. Several EuroSCORE II variables were independent risk factors for long-term mortality in a regression model, most of all very low ejection fraction (less than 20%), salvage operation, and dialysis. In the final model, isolated mitral valve surgery and isolated coronary artery bypass graft surgery were associated with improved long-term survival.


CONCLUSIONS
The EuroSCORE II cannot be considered a direct estimator of long-term risk of death, as its performance fades for mortality at follow-up longer than 30 days. Nonetheless, it is nonlinearly associated with long-term mortality, and most of its variables are risk factors for long-term mortality. Hence, they can be used in a different algorithm to stratify the risk of long-term mortality after surgery.
Department of Cardiac Surgery, S. Croce Hospital, Cuneo. Electronic address: fabarili@libero.it.
Fabio
F
Barili
Department of Cardiac Surgery, University of Bologna, Bologna.
Davide
D
Pacini
Department of Epidemiology, Regional Health Service, Lazio Region, Rome, Italy.
Mariangela
M
D'Ovidio
Department of Cardiothoracic Surgery, Queen's Heart Physician Practice, Honolulu, Hawaii.
Nicholas C
NC
Dang
Department of Cardiac Surgery, University of Milan, Milan, Italy.
Francesco
F
Alamanni
Department of Cardiac Surgery, University of Bologna, Bologna.
Roberto
R
Di Bartolomeo
Department of Cardiac Surgery, S. Croce Hospital, Cuneo.
Claudio
C
Grossi
Department of Epidemiology, Regional Health Service, Lazio Region, Rome, Italy.
Marina
M
Davoli
Department of Epidemiology, Regional Health Service, Lazio Region, Rome, Italy.
Danilo
D
Fusco
Unit of Cardiac Surgery and Translational Research, IRCCS Policlinico S. Donato, University of Milan, Milan, Italy.
Alessandro
A
Parolari
D000328:Adult; D000368:Aged; D002138:Calibration; D006348:Cardiac Surgical Procedures / Q000379:methods / Q000401:mortality*; D005060:Europe; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D012308:Risk Management / Q000379:methods*; D016019:Survival Analysis; D013997:Time Factors