Detection of inflammation in patients with acute aortic syndrome: comparison of FDG-PET/CT imaging and serological markers of inflammation.

Abstract

A substantial number of patients with acute aortic syndrome (AAS) require invasive therapy because of disease progression. Our study aimed to assess the impact of positron emission tomography (PET)/computed tomography (CT) and serological markers of inflammation to identify patients at high risk for disease progression. 33 patients with AAS (thoracic aortic aneurysm 5, thoracic aortic dissection 14, penetrating aortic ulcer 8, intramural haematoma 6) were included. After intravenous administration of [18F] fluorodeoxyglucose a non-contrast enhanced PET/CT of the body trunk and CT angiography of the entire aorta was performed. Serological levels of D-dimers and C-reactive protein (CRP) were measured in all patients. Follow-up imaging was performed to detect disease progression. 11 (33%) of 33 patients showed elevated tracer uptake within the aortic pathology, whereas 22 patients were PET-negative. In 23 patients a CRP level exceeding 1.0 mg/dl or a D-dimer level larger than 250 microg/l was found. The follow-up time was 224 (195) days. Nine of 11 PET-positive patients (82%) showed progression of AAS. In contrast, 55% of PET-negative patients showed stable disease or regression during the follow-up period. Kaplan-Meier analysis showed a clear, but not yet significant trend to longer survival in PET-negative patients, whereas elevated CRP and D-dimers did not allow for distinguishing of high-risk patients. Vessel wall inflammation was found in one-third of the patients with AAS and this patient group seems to have a high risk for disease progression. These initial results needs further investigation.