EuroSCORE vs. EuroSCORE II vs. Society of Thoracic Surgeons risk algorithm.

INTRODUCTION

This study presents a validation series for EuroSCORE II compared with the previous additive and logistic EuroSCORE and the Society of Thoracic Surgeons risk prediction algorithm.

PATIENTS AND METHODS

Clinical data of 2004 patients undergoing isolated coronary artery bypass surgery between 2006 and 2010 were retrospectively collected and individual expected risks of death were calculated by all 3 risk prediction algorithms. Performance of these risk algorithms was evaluated in terms of discrimination and calibration.

RESULTS

There were 76 deaths (3.8%) among 2004 patients. The mean EuroSCORE II predicted mortality was 3.72% ± 5.11%, additive EuroSCORE was 4.35%  ± 3.65% and logistic EuroSCORE was 6.41%  ± 10.06%. The additive EuroSCORE was better than EuroSCORE II in terms of both discrimination and calibration (C-statistic 0.866 and Hosmer-Lemeshow p value 0.230 vs. C-statistic 0.836 and Hosmer-Lemeshow p value 0.013 for EuroSCORE II). In a subset of 380 patients, we compared EuroSCORE II with the Society of Thoracic Surgeons risk prediction. Actual mortality was 2.89%. Predicted mortality by EuroSCORE II was 4.27%  ± 5.22% and Society of Thoracic Surgeons risk prediction was 2.30%  ± 4.16%. The area under the curve was 0.759 for EuroSCORE II and 0.898 for the Society of Thoracic Surgeons risk prediction, whereas the Hosmer-Lemeshow p value was 0.267 for EuroSCORE II and 0.981 for Society of Thoracic Surgeons risk prediction.

CONCLUSION

The Society of Thoracic Surgeons risk prediction algorithm is a better risk assessment tool compared to additive and logistic EuroSCORE and EuroSCORE II in Pakistani patients.