Aneurysm-express: human abdominal aortic aneurysm wall expression in relation to heterogeneity and vascular events - rationale and design.

Objective: Elective repair of abdominal aortic aneurysms (AAA) is associated with significant morbidity and mortality. Large amounts of AAA tissue are necessary to assess heterogeneity among AAA and to correct for potential confounders such as known risk factors. The Aneurysm-express study aims to identify different types of AAA using inflammatory markers in the aneurysm wall that predict postoperative cardiovascular adverse events and mortality, therefore allowing individual risk assessment.

Methods: The Aneurysm-express is an ongoing prospective cohort study including AAA patients undergoing open repair. At baseline, blood is drawn, relevant clinical data are collected and the standard diagnostic modalities are performed. During surgery a specimen of the ventral AAA wall is collected and processed to study protein expressions and histology. INTERIM RESULTS: The study commenced in 2003 in 2 medical centers and currently holds information and material of >300 AAA patients, making it the largest reported aneurysm biobank. Patients are followed for 3 years after surgery for occurring cardiovascular events. The current mean follow-up is 2.1 ± 1.3 years with an event rate of 27%.

Conclusion: The large amount of structurally stored tissue and blood combined with clinical characteristics and follow-up provide an excellent soil for indepth pathophysiological analyses, with assessment of AAA heterogeneity in combination with postoperative clinical outcome.