["Isolated" thrombi of the aorta: retrospective study of 10 observations]

Thrombi of the aorta are mostly linked to atheromatous plaques on the aortic wall of patients with classical risk factors for cardiovascular disease. The thrombus rarely appears on sound arteries and in this case is called "isolated".

We present a retrospective study of ten patients with "isolated" thrombi of the aorta treated between 1995 and 2004 at the Hospital of Grenoble. The following parameters were considered in this analysis: age of the patient when the thrombosis appeared, gender, cardiovascular risk factors, revealing mode of the thrombus, its anatomic location, biological and morphological exploration results and the treatment performed. Patients with atheromatous plaques on the aortic wall were excluded.

In eight out of ten cases the clinical presentation of the aortic thrombus is an acute ischemia of a limb. In all of the cases the diagnosis was confirmed by an injected thoraco-abdominal scan apart from one case where the primary diagnosis was made using an arterial echo-Doppler. The search for the thrombophilia can be considered to have been exhaustive in seven cases. For the search of an anti-phospholipid antibody syndrome this has been achieved in eight cases. Two etiologic diagnoses could be placed. The first one revealed during the aortic thrombosis a neoplasia of adenocarcinomic type without any primary identified. The second case was an essential thrombocythemia diagnosed one year after the thrombosis. The eight other cases remained "isolated" after an average 2.5 years follow-up.

Less than one hundred cases of aortic thromboses could be identified in the literature. The cases developing on a sound artery are difficult to quantify and the word "isolated" thrombus may be sometimes used by default. The hypothesis of an isolated focal atheromatous plaque or of inflammatory pathologies inducing a thrombus can be an example. The biological and morphological explorations have to be exhaustive even if in most of the cases they are not sufficient for the diagnosis. Therapy calls for anti-coagulation but is not standardized. The clinical follow-up appears to be essential since pathological conditions can possibly develop after the event of the thrombosis. It also enables refinement of the actions to be taken especially regarding long-term use of anticoagulants.