Abstract 484: Uptake of 18F-Fluorodeoxyglucose Detected by Positron Emission Tomography in the Abdominal Aortic Aneurysm is Correlated With Endoleaks and Predicts the Adverse Outcome of Aneurysm After Endovascular Aortic Repair
Endovascular aortic repair (EVAR) has been applied to abdominal aortic aneurysm (AAA) to decrease and prevent morbidity and mortality due to open surgery. However, this therapeutic approach may lead to complications such as occurrence of endoleaks which may result in rupture of the aneurysm. Decisions for complementary treatment after EVAR to prevent aneurysm rupture are based on endoleak characterization and aortic diameter evolution. The presence of endoleak or enlarging diameter is however not always predictive of rupture. Recent reports support the view that 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) provides unique information on cellular metabolic activity thought to drive aneurysm expansion and rupture.
We evaluated if FDG/PET could predict the outcome of aneurysm repaired by endoprosthesis. A cohort of 56 AAA patients (55 male; mean age of 74.6 years), treated by EVAR, underwent one or several PET/CT before and/or after surgery with a total number of 108 examinations. The quantification analysis of FDG uptake was not correlated to the AAA diameter but was strongly correlated with the presence of endoleak (55% of endoleak in patients with significant FDG uptake (PET+) versus 25% in PET0). Moreover, the PET+ AAA presented symptoms such as increasing diameter of aneurysmal sac (64% in PET+ versus 33% in PET0). On the other hand, two PET+ patients underwent conversion for open surgery for rapid growth and rupture with leaking. These outcomes did not occur among the PET0 patients. Increased circulating levels of fibrinolytic factors (D-dimers, thrombin/anti-thrombin and plasmin/anti-plasmin complexes) and inflammatory cytokines IL6 and IL8, were found in patients with endoleak while the collagenase MMP1 was largely decreased. Finally, two other MMPs, MMP12 and MMP13 were correlated with the uptake level of FDG.
Altogether, these results suggest that the presence of endoleak is associated with an activation of the fibrinolytic pathway and PET positivity induces factors involved in the extracellular matrix remodeling leading to instability of the wall and its rupture. This study suggests that PET/CT might predict the negative outcome of EVAR and represent a beneficial tool for patient management.
Author Disclosures: A. Courtois: None. G. Namur: None. M. El Hachemi: None. E. Cremmers: None. B. Nusgens: None. R. Hustinx: None. E. Allaire: None. J. Defraigne: None. A. Colige: None. N. Sakalihasan: None.
- © 2014 by American Heart Association, Inc.