Infected Superior Mesenteric Artery Aneurysm

Case Report

A 71-year-old woman presented to the emergency department with right upper quadrant abdominal pain and vomiting of 3 days. The patient was afebrile and white blood cell (WBC) count was within normal limits. The patient has a complex past medical history including left ventricular assist device (LVAD) that was complicated by methicillin-sensitive Staphylococcus aureus (MSSA) infection, and treated with 6 weeks of intravenous (IV) vancomycin. She was found to have methicillin-resistant S. aureus (MRSA)-positive blood cultures, and a computed tomographic (CT) scan revealed a 3.5 × 3.0 × 5.3 cm superior mesenteric artery (SMA) aneurysm ([Fig. 1]). Additional findings included a 2.2 × 2.3 × 2.1 cm gastroepiploic aneurysm and multiple enhancing splenic lesions, suspicious for abscesses versus mycotic pseudoaneurysms.

Fig. 1 (a–c) Enhanced axial, coronal, and 3D CTA images demonstrating a large SMA aneurysm (arrows).

Interventional radiologist recommended embolization after being consulted regarding treatment of the aneurysm. Following sedation and local anesthetic administration, the right common femoral artery was accessed and a 5F vascular sheath (Terumo, Tokyo, Japan) was placed. Next a 5F pigtail catheter was used to perform a flush aortogram (not shown), which showed no aortic abnormalities. An RC1 catheter (Cook Medical, Bloomington, IN) was used to catheterize the celiac artery and perform celiac angiography which revealed the large pseudoaneurysm. A Renegade STC 18 microcatheter (Boston Scientific, Marlborough, MA) was advanced into the lumen of the SMA aneurysm ([Fig. 2a]). Several microcoils (Interlock, Boston Scientific, Marlborough, MA) were placed into the aneurysm to promote thrombosis ([Fig. 2b]). Because of the perceived risk of intraprocedural rupture, the aneurysm sac was not packed with additional coils. Instead, a 5.3-mm MVP microvascular plug (Covidien, Irvine, CA) was deployed in the proximal artery to seal the aneurysm neck ([Fig. 2c]). Repeat angiogram of the SMA showed successful placement of the microvascular plug in the neck of the aneurysm and complete occlusion of the pseudoaneurysm. A second distal gastroepiploic pseudoaneurysm was then embolized with microcoils (not shown). A CT angiography CTA was performed the following day demonstrating successful embolization of both aneurysms ([Fig. 3]).

Fig. 2 (a) Spot fluoroscopic image demonstrating superior mesenteric artery (SMA) aneurysm during angiography (arrow). (b) Microcoil deployment within SMA aneurysm (arrow). (c) Intraprocedural image demonstrating successful coil (arrow) and vascular plug (open arrows) embolization of SMA aneurysm.

Fig. 3 (a–c) Enhanced axial, sagittal and 3D CTA images demonstrating successful embolization of superior mesenteric artery aneurysm (arrow).

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