Validating Three Scoring Systems for Predicting Mortality after a Ruptured Abdominal Aortic Aneurysm Repair in a Multicenter New Zealand Population

BACKGROUND: Several scores exist to predict 30 day mortality after intervention for a ruptured abdominal aortic aneurysm (rAAA). This multicenter study is the first to compare the performance of three scores in an Australasian cohort, including nonoperative and indigenous populations. METHODS: All patients presenting with an rAAA managed operatively and nonoperatively between 2010 and 2024 to five hospitals in the Midland region of New Zealand were included. Three risk prediction scores were calculated: Harborview Risk Score (HRS), Edinburgh Ruptured Aneurysm Score (ERAS), and Glasgow Aneurysm Score (GAS). The discriminative ability of the scores was calculated using receiver operating characteristics curves. RESULTS: A total of 256 patients were included in this study. The HRS score was a better predictor of 30-day mortality in both operative groups, with an area under the curve (AUC) of 0.83 (P value 0.042 versus all) in the endovascular group and 0.69 (P value 0.086 versus all) in the open repair group. The ERAS and GAS scores had an AUC 0.664 and 0.612, respectively, and thus performed less well at predicting 30-day mortality. There was a 2.4-fold increase in 30-day mortality with each increase in HRS point (odds ratio 2.4, 95% confidence interval 1.68-3.56, P value <0.001). CONCLUSION: Of all the scores, the HRS demonstrated the best discriminative ability to predict 30-day mortality in open and endovascular repairs. The risk prediction scores in conjunction with clinical assessments of patients can be used to assist in the clinical decision-making process for patients presenting with an rAAA.