insufficient patient recruitment

Clinical outcomes of chronic type B aortic dissections are unknown, especially in case of false lumen expansion and risk of rupture. Data of literature give us some indications about prognosis. The 1-year survival rate is about 80%, but we deplore the 25% rate of mortality at 3 years despite follow-up.The only known predictive factors are the initial diameter of more than 4 cm and the persistence of a false lumen patent.However, actual means of follow-up do not allow to predict severe complications. The aim of the sudy is to propose a diagnostic and preventive strategy for the follow-up of chronic type B aortic dissections treated medically.

The primary objective is then to evaluate the prognostic role of 18-FDG-PET Scan in such patients in order to predict the risk of aortic diameter growth of more than 5 mm in 1 year and/or of an aortic dissections extension at 1 year. The secondary objectives are to evaluate the link between fibrosis biomarkers MMP et TIMP) and the results of imaging results (evolution of diameter and extension and results of PET-Scan imaging) Methods: 100 patients to be included in 3 years History of chronic type B aortic dissection, treated medically, evolving since more than 1 month and less than 5 years.

Expected results: Prognostic contribution of 18FDG-PET-Scan and biomarkers for the identification of patients at high risk of evolution. Elaboration of a decisional algorithm about follow-up modalities of chronic aortic dissections. Demonstration of a correlation between aortic diameter growth or aortic dissection extension and intensity of marker fixation with 18-FDG-PET-Scan.

Inclusion Criteria:

• Patients over 18 years old
• Chronic type B aortic dissection, without surgical treatment
• Medically treated patient
• Medical treatment since more than 1 month and less than 5 years
• Aortic dissection localization : below left subclavian artery and alow femoral artery
• Affiliation to a social security system
• Patient who have given informed consent

Exclusion Criteria:

• History of malignant pathology
• Aortic dissection since less than 1 month or more than 5 years
• Inflammatory or infectious disease of the aorta
• Uncontrolled infectious disease
• Iodine Allergy
• Severe renal insufficiency (cockcroft clearance <30 mL/min)
• Patient under guardianship or curators
• Any associated medical or psychological condition wich could compromise the patient's ability to participate in the study
• Inability to be submitted to the study follow-up for geographical, social or psychological reasons
• Current pregnancy or lack of effective contraception during their reproductive years
• Suckle

Patients suffering from chronic type B aortic dissection (since more than 1 month and less than 5 years)and medically treated.