Background: Mobile intra-aortic thrombus without atherosclerosis, aneurysm, or congenital coagulopathy is very rare, and there are few reports especially in young or middle-aged patients. Furthermore, there are presently no established guidelines or common strategies for the treatment of mobile intra-aortic thrombus. In this case report, we describe the first case of intra-aortic thrombus caused by secondary erythrocytosis and describe the recommended treatment strategy for intra-aortic thrombus.
Case presentation: We report a case of an independent 40-year-old Asian man with a current history of heavy cigarette smoking who had sudden onset of abdominal and lumbar pain. Contrast-enhanced computed tomography revealed partial renal and splenic infarction, and he was transferred to our hospital. He also had a large mural thrombus in his thoracoabdominal aorta. Blood analysis on admission showed a hemoglobin level of 19.4 g/dL and hematocrit of 54.3 %; his international normalized ratio of prothrombin time, fibrin degradation products, and activated partial thromboplastin time levels were 1.02, 2.8 μg/ml, and 26.9 seconds respectively. We could find no abnormalities in protein C and protein S activity levels. Lupus anticoagulant and anti-cardiolipin antibody were both negative. He had no past medical history of arrhythmia and we found no signs of an arrhythmic event during admission. We promptly started anticoagulant therapy, but as the thrombus seemed at high risk of causing further critical infarction, we performed emergency aortic thrombectomy using partial extracorporeal circulation. To prevent dissemination of the thrombus during extracorporeal circulation, we first clamped his proximal and distal aorta on either side of the thrombus just before initiating extracorporeal circulation. After the aortotomy we removed a 14-cm length of intra-aortic thrombus without residual lesion. He was discharged from our hospital 20 days after surgery. From the results of his blood analysis, we considered the only cause of this thrombus was secondary erythrocytosis, which was probably induced by his current heavy cigarette smoking.
Conclusion: We are the first to report such a thrombosis caused by secondary erythrocytosis and conclude that once the diagnosis of intra-aortic thrombus with systemic embolism is clear, emergency surgical removal of such a thrombus must be considered to prevent further embolic complications.
Keywords: Erythrocytosis; Infarction; Intra-aortic thrombus; Surgical thrombectomy.