Evaluation of Predictors of Aortic Aneurysm Growth and Rupture

The goal is to non-invasively study the metabolic processes within the aortic wall that are thought to explain progression to clinical manifestations of an aortic aneurysm. Hypothesis is that the non-invasive imaging of Abdominal Aortic Aneurysm (AAA) with contrast ultrasound, coupled with serum biomarker measurements will allow the identification of the vulnerable aortic wall and patients who are at risk of AAA growth or rupture.

Aim#1: Prospective Contrast Ultrasound (CUS) imaging of patients with AAA to predict AAA growth and test gender differences in rate of growth and rupture. Aim#2: Serum biomarker testing of patient with AAA. CUS findings will be correlated with serum biomarkers and AAA wall histology. Prospective Contrast Ultrasound imaging of patients with AAA as part of a pilot feasibility study to predict AAA growth and test gender differences in rate of growth and rupture. CUS findings will be correlated with serum biomarkers and AAA wall histology. Potential significance: This study will evaluate the AAA wall and will be based on detecting areas of increased vasa vasorum density within the aneurysm wall and intraluminal thrombus, which indicate regional ischemia and inflammation of the aortic wall and propensity for weakening, enlargement or rupture. This novel evaluation of the aortic wall in patients with AAA will allow individualized treatment based on the biological potential for growth and rupture.

Definity® is the contrast agent that will be administered by intravenous injection by a registered nurse during the ultrasound (contrast enhanced ultrasound (CUS). The purpose is to assist in identifying differences in AAA characteristics based on gender and AAA stability and growth.

Systemic serum biomarkers of AAA will be measured. These markers are circulating levels of Vascular Endothelial Growth Factor, C Reactive Protein, cytokines and osteoprotegerin.

Serum markers will be drawn at each follow up visit until if/when AAA is repaired. They will also be measured 1 year after repair.

Inclusion Criteria: Diagnosis of AAA with confirmation of diagnosis of any size aneurysm with imaging. 21 years of age or older ability to give informed consent. Exclusion Criteria: Inability to provide an informed consent Known allergy to Definity Unstable cardiopulmonary conditions pregnancy