Does the EuroSCORE predict mortality following adult cardiac surgery in the UK?
E McLaughlin, K Wynne-Jones, B Fabri, M Jones and B Bridgewater
Departments of Cardiothoracic Surgery and Clinical Audit
Wythenshawe Hospital, Manchester and The Cardiothoracic Centre - Liverpool NHS Trust, Liverpool
Objectives - To study the use of the EuroSCORE system to predict mortality following adult cardiac surgery in the UK
Design - Retrospective study
Setting All centres performing adult cardiac surgery in the Northwest of England
Subjects 4346 patients undergoing surgery between April 1997 and March 1998
Main outcome measures Predicted mortality was derived from patient risk factors by the EuroSCORE method. In hospital mortality was recorded for all patients. The predictive ability of the model was studied by ROC curve analysis. Subgroup analysis was performed on patients undergoing CABG alone, patients undergoing valve surgery, female patients and patients aged 70 years or over.
Results The observed postoperative mortality was 3.6% compared to a predicted mortality by the EuroSCORE of 4.4. The predictive ability of the model was good, as shown by an area under the ROC curve of 0.76. The observed mortality, expected mortality and the area under the ROC curve for the subgroups were as follows: CABG only observed 2.4%, expected 3.9%, ROC area O.73, valve surgery - observed 7.4% expected 6.2%, ROC area 0.71, female gender - observed 5.3%, expected 5.6%, ROC area 0.71, age>70 years - observed 6.5%, expected 6.9%, ROC area 0.71.
Conclusions The EuroSCORE is a good overall predictor of operative mortality following adult cardiac surgery in the Northwest of England. The observed mortality was slightly lower than predicted by the model. There were some differences in the predictive ability of the model between the various subgroups, and some reservations should be exercised when using the model on populations which differ significantly in the incidence of risk factors from the population from which the model was derived until further validation studies have been performed.
