Comparison of the additive, logistic european system for cardiac operative risk (EuroSCORE) with the EuroSCORE 2 to predict mortality in high-risk cardiac surgery.

Background: The aim of this study was to compare the new EuroSCORE (ES) 2 prediction model in high-risk patients with the 2 other oldest additive ES (aES) and logistic ES (lES).

Methods: Consecutive adult patients undergoing all cardiac surgery except heart transplantation and left ventricular assist device were included. The 3 risk scores were collected before surgery. We defined 4 high-risk groups of patients, patients ≥80 years, combined cardiac surgery, surgery of the thoracic aorta, and emergency cardiac surgery, and 2 low-risk groups, valve surgery and coronary artery bypass surgery. The predicted value of each score has been assessed by the area under the receiver operating characteristics curve (AUC).

Results: The study had included 3301 patients. Thirty-day mortality was 3.9% (95% confidence interval (CI), 3.3 - 4.6%). The AUC of ES2 was 0.81 (0.77 - 0.84), 0.82 (0.78 - 0.85), 0.70 (0.64 - 0.76), 0.79 (0.74 - 0.83), 0.85 (0.83 - 0.87), and 0.88 (0.86 - 0.90) for octogenarians, thoracic aortic surgery, combined surgery, emergency surgery, coronary surgery, and valve surgery, respectively. These ES2 AUC values were higher than those obtained with the aES for octogenarians, and with the lES for octogenarians and valve surgery. The ES2 calibration was better than the aES and lES calibration for the whole population, and low-risk groups. The ES2 calibration was superior to aES and lES in high-risk groups, except for octogenarians and thoracic aortic surgery compared to lES.

Conclusion: In high-risk cardiac surgery patients, ES2 only marginally improve the predicted 30-day mortality in comparison to other ES.