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Clot in bovine arch diagnosed by transesophageal echocardiography.

January 2014 • Volume 118 • Number 1 A 45-year-old African-American man presenting with chest pain radiating to his back was found to have a Stanford type B dissection on computed tomography (CT) scan, with the flap originating distal to the left subclavian artery (LSCA) and not involving the arch. The scan also revealed a “bovine arch” pattern of vessel branching (Fig. 1). The patient was initially treated medically with antihypertensive drugs but lost left lower extremity pulses and became obtunded on hospital day 2, requiring intubation. A head CT demonstrated an old lacunar infarct but no acute process, and a repeat chest CT confirmed the LSCA origin of the dissection without significant change from the original scan. He was taken emergently to the operating room for a femoralfemoral arterial bypass and, because of his declining mental status in the context of an aortic dissection, possible chest exploration for retrograde extension of the dissection. Intraoperative transesophageal echocardiography (TEE) was performed that demonstrated the dissection flap in the LSCA and an entry point just distal to it (Video 1, see Supplemental Digital Content 1, http://links.lww.com/ AA/A685), without any flap noted in the ascending aorta. By turning the probe to the right from the LSCA, the bovine trunk, measuring 24 mm in diameter, was clearly seen (Fig. 2). Compared with the LSCA, there was qualitatively less color flow Doppler signal obtained in the trunk, and the velocity-time integral (VTI) by pulse wave Doppler was significantly lower (Video 2, see Supplemental Digital Content 2, http://links.lww.com/AA/A686). Given these data suggesting reduced flow in the bovine trunk, along with the patient’s clinical picture, sternotomy was performed. Surgical inspection of the aorta revealed a blue discoloration of the arch and, after aortotomy, extension of the dissection into the bovine trunk that contained mural clot. Circulatory arrest with selective antegrade cerebral perfusion was initiated, and a total arch replacement was performed with reimplantation of the LSCA and bovine trunk into a Hemashield® graft. Total body perfusion was reestablished, and the patient was weaned from cardiopulmonary bypass after 257 minutes. The patient was taken to the intensive care unit in stable condition, although his postoperative course was complicated by multiple cerebral infarctions and eventual transfer to a long-term acute care facility on postoperative day 19. Consent for publication of this case was obtained from the patient’s family.