Thrombosis of Abdominal Aortic Aneurysms

Backgrounds: Abdominal aortic aneurysms (AAA) are usually associated with a mural thrombus. Some data suggest that aneurysmal evolution correlates with the biological activity of the thrombus. Aims: We aimed to assess if the rate of increase in diameter of AAA is related with increased thrombus growth and rupture. Methods: A total of 82 patients with AAA hospitalized in our Internal Medicine Department between 2002 and 2007. All patients underwent clinical examination, ECG, laboratory tests; abdominal ultrasonography and computed tomography (CT) were performed to measure the diameter of the aneurysms and also the diameter of the lumen and to evaluate presence, volume and characteristics of thrombus. Results: There were 25 patients with AAA with diameter over 5 cm; 23 of the 25 patients did not undergo surgical procedure because of multiple absolute contraindication. Thrombosis of AAA was noticed in 78 patients. Thrombus location was concentric in 62 patients and eccentric posterior in 16 patients. CT examination in patients with rupture of the aneurysms have showed contrast in the thrombus suggesting bleeding into it. Ruptured AAA (9 patients) were larger in diameter compared with intact AAA (7,1 cm vs 6,4 cm) and the size of thrombus were also larger in patients with ruptured AAA compared with intact AAA. Conclusions: Thrombosis of AAA is not a rare condition. Thrombus formation and accumulation of inflammatory cells may perturb stability of the aortic wall. Computed tomography (CT) is a very useful examination for diagnosis and monitoring the abdominal aortic aneurysms complicated with thrombosis. CT examination of patients with rupture of aneurysms have demonstrated contrast appearing in the thrombus suggesting bleeding into it.