Thrombosis of the descending thoracic aorta: a case report

A 76-year-old woman with primary polycythemia vera had emboli to both superficial femoral arteries and to a branch of the superior mesenteric artery. Polycythemia vera is a neoplastic disease of bone marrow stem cells in which increased red cell production leads to hyperviscosity manifested by propensity to thromboembolic phenomena. These problems usually occur in smaller vessels, sparing large vessels that have high blood flow. The patient underwent an extensive investigation to determine the source of the emboli. Abdominal aortic angiograms and cardiac echogram failed to reveal the source. An esophageal echogram showed free-floating thrombus in the descending thoracic aorta, which was confirmed by magnetic resonance imaging. A thoracic aortic thrombectomy was performed. Embolic phenomena ceased and postoperative esophageal echogram confirmed a clear thoracic aorta. Although extremely rare in the descending thoracic aorta, thrombus formation may occur in association with polycythemia vera and should be sought when usual investigations fail to reveal the source.