Abstract 526: Thromboembolic Phenomenon in a Patient With Unexplained Transverse Aortic Thrombus

Abstract

A 55 year-old Caucasian male, with no known past medical history, presented to the ER complaining of left upper extremity pain with finger tingling and difficulty speaking that started 8 hours before presentation, while driving his car. In the ER, physical exam was remarkable for mild expressive aphasia with difficulty finding words. His left arm was tender without any edema or erythema and normal range of motion. His left hand fingertips appeared cyanotic ( Picture 1) , however his radial and ulnar pulses were intact bilaterally. Laboratory evaluation revealed a platelet count 1,416,000/mcl, and normal PT/INR and PTT. CT of the brain showed no intracranial bleed. MRI of the brain showed multiple small sub-acute infarcts in the left occipital lobe, left basal ganglia and bilateral cerebellar hemispheres suggesting a shower of emboli. Because of a concern for possible aortic dissection by the ER physician, a CT angiogram of the chest was done. It revealed a large filling defect (up to 3.1 cm) in the distal transverse thoracic aorta, consistent with non-occlusive thrombus adjacent to the origin of the left subclavian artery ( Picture 2) . Subsequently, TEE was done and again showed a large mobile thrombus attached to the inferior posterior wall of the transverse thoracic aorta ( Picture 3) . Given the extremely mobile and large sized thrombus, with high risk for further embolization, the patient underwent surgery with excision of the aortic thrombus ( Picture 4) . The patient had an uncomplicated post-operative course and warfarin was started empirically post-operatively. Further Hematology work up was suggestive of Essential Thrombocytosis. The patient was started on hydroxyurea. On his 3-week follow up appointment, his platelet count decreased to 202,000/mcl. Anti-coagulation was continued for 3 months. His neurologic symptoms significantly improved with only mild residual left hand finger tips claudication which resolved by 1 month post discharge.