gms | German Medical Science

131. Kongress der Deutschen Gesellschaft für Chirurgie

Deutsche Gesellschaft für Chirurgie

25.03. - 28.03.2014, Berlin

External validation of six risk prediction models for patients undergoing elective open or endovascular repair of abdominal aortic aneurysm to predict immediate postoperative outcome

Meeting Abstract

  • Michael Gawenda - Klinikum der Universität zu Köln, Klinik für Gefäßchirurgie, Köln
  • Payman M. Majd - Klinikum der Universität zu Köln, Klinik für Gefäßchirurgie, Köln
  • Andreas Zimmermann - Klinikum der Universität zu Köln, Klinik für Gefäßchirurgie, Köln
  • Jan Brunkwall - Klinikum der Universität zu Köln, Klinik für Gefäßchirurgie, Köln

Deutsche Gesellschaft für Chirurgie. 131. Kongress der Deutschen Gesellschaft für Chirurgie. Berlin, 25.-28.03.2014. Düsseldorf: German Medical Science GMS Publishing House; 2014. Doc14dgch427

doi: 10.3205/14dgch427, urn:nbn:de:0183-14dgch4277

Published: March 21, 2014

© 2014 Gawenda et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Introduction: New risk prediction models have been developed taking into account the special circumstances for endovascular aneurysm repair (EVAR). The aim of this study is to determine whether these newly developed risk prediction models as well as older risk prediction models can be used to calculate 30-day mortality after elective open or endovascular abdominal aortic aneurysm repair.

Material and methods: Data of 707 patients that underwent elective open or endovascular AAA repair at a university vascular centre, from June 1998 to December 2010 were analysed using a prospective database. Examined scores were the Glasgow Aneurysm Score (GAS), the Revised Cardiac Risk Index (RCRI), the Combined prognostic Index (CPI), the Vascular Study Group of New England Cardiac Risk Index (VSG-CRI), the Medicare-Model and the Australian-Audit Score. 30-day mortality was used as an endpoint. The discriminative ability of all risk prediction models was studied by calculating the area under the curve after plotting the receiver-operator characteristic curves.

Results: Endovascular aneurysm repair (EVAR) was performed in 366 (51.8%) patients and open repair (OR) in 341 (48.2%) patients. The 30-day mortality rate for patients with EVAR was 1.6%, and for patients undergoing OR 1.5% (p=0.853).

The best performing score for patients undergoing OR was the CPI with an AUC of 0.780 (95% CI, 0.64-0.95; S.E. 0.08; P=0.024). The Medicare-Model with an AUC of 0.780 (95% CI, 0.64-0.93; S.E. 0.07; P=0.032), the VSG-CRI 0.773 (95% CI, 0.60-0.95; S.E. 0.09; P=0.061), the GAS 0.771 (95% CI, 0.59-0.95; S.E. 0.09; P=0.038), and the RCRI 0.763 (95% CI, 0.51-1.00; S.E. 0.13; P=0.044) also revealed good discriminative ability. The performance of the Australian-Audit Score was poor with an AUC of 0.671 (95% CI, 0.40-0.94; S.E. 0.14; P=0.188).

For patients undergoing EVAR the best performing score was the Medicare-Model with an AUC of 0.806 (95% CI, 0.55-1.00; S.E. 0.13; P=0.010). Also the GAS 0.741 (95% CI, 0.56-0.93; S.E. 0.09; P=0.043) and the VSG-CRI 0.715 (95% CI, 0.45-0.99; S.E. 0.14; P=0.140) were performing well. All the other Scores had an AUC less than 0.70 indicating poor discriminative ability for predicting postoperative death within 30 days.

Conclusion: The majority of scores are predictive for immediate postoperative outcome after open repair. For patients with EVAR, new scores like the Medicare-Model demonstrated good performance for predicting immediate postoperative outcome. Older scores should only applied with caution in this group of patients showing poor performance in this study.