Assesment of the EuroSCORE as a predictor for mortality in valve cardiac surgery at the Heart Institute of Pernambuco

Objective: To assess the applicability of the European Rysk System in Cardiac Operations (EuroSCORE) in patients undergoing cardiac valve surgery at the Heart Institute of Pernambuco. Method: 840 patients operated on between 2001 and 2009, who medical records contained all the informations to calculate the EuroSCORE were included in the study. Hospital death was the end-point of the study. In order to assess the applicability of the EuroSCORE it was used the non parametric test of Mann-Whitney. The calibration of the model was measured by comparing the morbidity observed with that expected, using the Hosmer-Lemeshow Test of Goodness of Fit. The accuracy of the model was evaluated by the ROC curve (receiver operating characteristic curve). Results: The comparison of expected and observed mortality, by Hosmer-Lemershow test, showed good predictive capacity (P = 0.767) as well as when compared to each value of addictive EuroSCORE (P = 0,455). The area of ROC curve was 0.731 (IC 95%, 0.660 - 0.793) with P < 0.001. The global predicted mortality was practically identical to that observed (7.9%). The low-risk group (EuroSCORE 0-2) comprised 345 patients with a mortality of 3.19%. The medium-risk group (EuroSCORE 3-5) comprised 364 patients, with a mortality of 7.69% and the high-risk group (EuroSCORE > 6) included 131 patients, with a mortality of 20.6%. The regression logistic analyses allowed to identify the following risk-factors for death: age > 60 years, gender female, previous operation, active endocarditis, associated surgery of the thoracic aorta and extra-cardiac arteriopathy. Conclusion: The EuroSCORE, a simple and objective method, proved to be a satisfactory predictor of operative mortality and risk factors for death in patients submitted to valve cardiac operations in the Heart Institute of Pernambuco.