Comparative study on clinical and imaging characteristics between patients with ruptured and large, unruptured abdominal aortic aneurysms

Purpose to determine potential clinical and computed tomography (CT) imaging predictors for abdominal aortic aneurysm (AAA) rupture based on a comparative analysis of patients presenting with large (> 6.5 cm diameter) unruptured AAA (uAAA) and patients presenting with ruptured AAA (rAAA) respectively. Methods consecutive patients presenting with large unruptured or rAAA and having undergone a contrast-enhanced CT at admission between January 2005 and June 2019 were included. Patients’ demographics and CT-imaging characteristics were collected from the institutional electronic medical records. Both patient groups were compared using Fisher’s exact test for categorical variables and the Mann-Whitney U test for continuous variables. Results we included 101 patients, of which 57 patients presenting with a rAAA and 44 patients with a large, uAAA. Patients in the large, uAAA group were younger, mean age of 76 years vs 83 years (P < 0.001), had less coronary artery disease (47.6% vs 72.5%; P = 0.026) and had a lower left common iliac artery to maximum aneurysm diameter ratio (0.15 vs 0.18; P = 0.034), a lower sum of right + left common iliac artery to maximum aneurysm diameter ratio (0.31 vs 0.39; P = 0.028) and a lower infrarenal neck to maximum aneurysm diameter ratio (0.29 vs 0.35; P = 0.039). Conclusion patients with large, uAAA’s were younger with less coronary artery disease and presented with lower ratio of right + left common iliac artery to maximum aneurysm diameter as well as a lower ratio of infrarenal neck to maximum aneurysm diameter on CT-imaging compared to patients with rAAA.