Meandering Mesenteric Bypass: A Case Report on a Novel Surgical Technique for Managing Mesenteric Ischaemia When Endovascular Fails.

INTRODUCTION

Endovascular revascularisation (ER) is often used as first line treatment for chronic mesenteric ischaemia, with high technical success and a lower rate of peri-operative adverse events than open surgical repair. Distal embolisation following ER is a potentially life threatening complication with a high mortality rate.

REPORT

A 66 year old patient with a two year history of postprandial abdominal pain presented with two weeks of constant abdominal pain. Computed tomography angiography (CTA) demonstrated extensive atherosclerotic disease within the coeliac artery (CA), superior mesenteric artery (SMA), inferior mesenteric artery (IMA), aorta, and iliac arteries. Stenting of the CA was successful. Four hours post-intervention, the patient became unstable with worsening abdominal pain. Repeat CTA showed signs of acute bowel ischaemia (pneumatosis, mural hypo-enhancement, and intravascular gas) despite a patent CA stent. Microemboli trashing secondary to ER was suspected.The patient was taken for an emergency laparotomy. The SMA was an unsuitable bypass target due to extensive atherosclerosis, and bypass to the CA was unlikely to improve perfusion, given the patent stent. A large, disease free collateral artery was identified as a potential bypass target, and a six mm Dacron graft was successfully anastomosed from the right external iliac artery to the Arc of Riolan. At the relook laparotomy, the iliac-mesenteric bypass graft was covered and the abdomen was closed. The patient has since had complete resolution of symptoms and 12 kg of weight gain at six months.

DISCUSSION

This is a unique case in which the Arc of Riolan was used as a bypass target in the context of acute on chronic mesenteric ischaemia. It highlights the possibility of collateral mesenteric vessels as potential bypass targets when the mesenteric trunks are unsuitable. Good knowledge of collateral vessel anatomy and careful pre-operative planning is critical in patients with extensive disease that is not amenable to traditional treatment.