Isolated Dissection of the Superior Mesenteric Artery with Associated Median Arcuate Ligament Compression of the Celiac Artery in an Asymptomatic Patient

Abstract

Introduction A 45-year-old man presented to the vascular laboratory for evaluation of an abdominal bruit and was found to have a superior mesenteric artery (SMA) dissection in conjunction with median arcuate ligament syndrome. This case study details the course of his evaluation and the importance of thorough examination in ultrasound exams. Methods A duplex ultrasound exam was performed with an ATL HDI 3500 sonographic unit with a 5.2 MHz curvilinear transducer. Results A 45-year-old asymptomatic white man reported to his physician for a routine physical. During the examination, the physician heard an abdominal bruit and referred the patient to the vascular lab for a mesenteric duplex ultrasound. The duplex ultrasound showed chronic dissection of the SMA with severe narrowing in the true lumen, and the celiac artery Doppler showed classic velocity increase with respiratory variation consistent with Median Arcuate Ligament Syndrome. A computed tomography angiogram later confirmed the diagnosis. Conclusion Isolated SMA dissection is an exceedingly rare condition that has only been reported 55 times in literature. Median arcuate ligament syndrome occurs more frequently, but its presence in conjunction with SMA dissection has only been reported in literature once. Undiagnosed SMA dissection can lead to bowel necrosis, mesenteric ischemia, or death. The careful attention by the referring physician to an abdominal bruit and the prompt use of Duplex ultrasound facilitated the discovery of a rare, serious, and potentially fatal dissection of the SMA, as well as median arcuate ligament syndrome.