Mural aortic thrombi: An important cause of peripheral embolization

Purpose: Arterial thromboembolism in patients with. an unknown source of em bolization is still associated with significant morbidity and mortality. Th e advent of transesophageal echocardiography (TEE) and magnetic resonance i maging (MRI) and the more frequent use of computed tomography (CT) have led to the identification of mural aortic thrombi (MAT) as a source of distal embolization in a much higher proportion of patients than previously apprec iated. The incidence, diagnosis, and treatment of patients with MAT is repo rted. Methods: Ln a prospective study, from January 1996 to December 1998, 89 pat ients with acute embolic events underwent an extensive diagnostic workup, c onsisting of TEE, CT, or MRI, to detect the source of embolization. Patient s in whom the heart (n = 51), occlusive aortoiliac disease (n = 16), or aor tic aneurysms (n = 12) was identified as the source of embolization were ex cluded. Results Five female and three male patients, with a median age of 63 years (range, 35 to 76 years), with bilateral or repetitive embolic events result ing from MAT were identified, representing 9% of all patients with arterial thrombembolism, All patients had several risk factors for atherosclerosis, but only one young patient had a single risk factor that promoted thrombos is. Successful percutaneous catheter aspiration embolectomy was performed i n six patients. The remaining two patients underwent surgical thromboembole ctomy. A below-knee amputation had to be performed in two patients, thus re presenting a morbidity of the primary treatment of 25%. MAT of equal value were detected in the ascending (n = 1) and thoracic aorta (n = 3) by means of TEE, CT, or MRI. MAT in the abdominal aorta (n = 4) were identified by m eans of CT and MRI. Surgical removal of MAT was performed in seven patients by means of graft replacement of the ascending aorta (n = 1), open thrombe ctomy of the descending aorta (n = 2), and thrombendarterectomy of the abdo minal aorta (n = 4), without intraoperative or postoperative complications, No recurrence of MAT occurred during a median follow-up period of 13 month s (range, 4 to 24 months). Conclusion: MAT represent an important source of arterial thrombembolism. A diagnostic workup, of the aorta, preferably by means of CT or MRI, should be performed in all patients in whom other sources of embolization have bee n ruled out. The ideal therapeutic approach to these patients still a-waits prospective evaluation, However, based on our experience, MAT can be succe ssfully treated with a definitive surgical procedure in selected patients, with low mortality and morbidity.