Cardiac operative risk evaluation: The EuroSCORE II, does it make a real difference?

The EuroSCORE, worldwide used as a model for prediction of mortality after cardiac surgery, has recently been renewed. Since October 2011, the EuroSCORE II calculator is available at the EuroSCORE website and recommended for clinical use. The intention of this paper is to compare the use of the initial EuroSCORE and EuroSCORE II as a risk evaluation tool.

100 consecutive patients who underwent combined mitral valve and coronary bypass surgery (MVR + CABG) and 100 consecutive patients undergoing combined aortic valve surgery and coronary bypass surgery (AVR + CABG) at the Radboud University Nijmegen Medical Center before 10 October 2011 were included. For both groups the initial EuroSCORE and the EuroSCORE II model were used for risk calculation and based on the calculated risks, cumulative sum charts (CUSUM) were constructed to evaluate the impact on performance monitoring.

For the MVR + CABG group the calculated risk using the initial logistic EuroSCORE was 9.95 ± 8.47 (1.51-45.37) versus 5.08 ± 4.03 (0.67-19.76) for the EuroSCORE II. For the AVR + CABG group 9.50 ± 8.6 (1.51-69.5) versus 4.77 ± 6.6 (0.96-64.24), respectively. For both groups the calculated risk by the EuroSCORE II was statistically lower compared with the initial EuroSCORE (p < 0.001). This lower expected risk has influence on performance monitoring, using risk-adjusted CUSUM analysis.

The EuroSCORE II, based on a recently updated database, reduces the overestimation of the calculated risk by the initial EuroSCORE. This difference is statistically significant and the EuroSCORE II may also reflect better current surgical performance.