Objective risk-scoring systems for repair of abdominal aortic aneurysms: Applicability in endovascular repair?

Objectives: Recent studies propose the use of objective risk-scoring systems as a clinical tool. for selecting patients for open or endovascular abdominal aortic aneurysm repair (EVR). The aim of this study was to evaluate four established risk-scoring systems for accuracy of prediction of early mortality and morbidity following EVR. Patients and methods: 266 consecutive patients undergoing elective EVR at St. George's Vascular Institute between July 2001 and January 2007 were studied using a prospective database. The Glasgow Aneurysm Score (GAS), the Vascular Physiology and Operative Severity Score for the enUmeration of Mortality and Morbidity (V-POSSUM), the modified Customised Probability Index (m-CPI) and the Customised Probability Index (CPI) were applied for prediction of 30-day mortality and morbidity. Accuracy of prediction was compared using receiver operating characteristics (ROC) curve analyses. Results: 30-day mortality and morbidity rates were 4% (11/266) and 8% (22/266) respectively. For prediction of mortality, GAS, V-POSSUM, m-CPI and CPI ROC curve analyses showed areas under the curves (AUCs) of 0.68 (95% confidence interval (CI), 0.48-0.87; p = 0.046), 0.66 (95% CI, 0.51-0.81; p = 0.067), 0.63 (95% Cl, 0.45-0.81; p = 0.148) and 0.65 (95% CI, 0.49-0.80; p = 0.101) respectively. Corresponding AUCs for prediction of morbidity were 0.64 (95% CI, 0.51-0.76; p = 0.511), 0.62 (95% CI, 0.51-0.74; p = 0.505), 0.54 (95% CI, 0.41-0.67; p = 0.416) and 0.55 (95% Cl, 0.42-0.68; p = 0.451). Conclusions: GAS, V-POSSUM, m-CPI and CPI were poor predictors of early mortality and morbidity following EVR in this series. Caution should be applied to the use of these scoring systems for pre-operative risk stratification and treatment selection for endovascutar repair of abdominal aneurysms. (C) 2008 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.