GENERAL CONSIDERATIONS AND HISTORY
Chronic mesenteric ischemia (CMI), also known as intestinal angina, is characterized by abdominal pain after meals due to low mesenteric blood flow as a result of mesenteric occlusive disease. Although atherosclerotic disease in the mesenteric vascular bed is quite common, intenstinal angina is rare.1,2 The prevalence of CMI is estimated to be 1 in 100,000 of the annual US hospital admissions and accounts for 2% of admissions for gastrointestinal (GI) conditions.3 CMI is more commonly seen in females compared to males and atherosclerotic disease in the most common underlying pathology.3,4 The majority of the clinical presentation of this disease process can be attributed to the decreased blood flow. After ingestion of a meal, blood flow increases to around 2000 cc/hr over the following 3 to 6 hours in order to provide adequate oxygenation to the GI system.4,5 Patients with mesenteric ischemia are unable to mount this postprandial hyperemic response that is required for adequate oxygenation and energy to proceed with the metabolic processes of secretion and absorption as well as peristalsis. As such, intestinal angina results from visceral organs failing to meet the regular metabolic requirements. However, the mesenteric circulation is a complex network involving multiple collateral, and due to this, one may not develop symptoms until at least two of the three major mesenteric vessels—the superior mesenteric artery, inferior mesenteric artery, or celiac axis (SMA, IMA, or celiac axis)—are completely occluded or severely narrowed.6
Mesenteric ischemia can be characterized as either acute or chronic based on the acuity and duration of the symptoms. Chronic mesenteric ischemia progresses over weeks or months, and the most common cause being occlusive disease secondary to atherosclerotic disease process. This chapter will discuss the clinical findings, differential diagnosis, the surgical and endovascular management of chronic mesenteric ischemia.4
When approaching a patient with suspected mesenteric ischemia, it is imperative to obtain a thorough history and physical exam as symptoms of mesenteric ischemia can sometimes mimic other disease processes and vice versa. Frequently, patients will complain of postprandial abdominal pain which is seen 15 to 60 minutes after a meal. The pain is quite reproducible and described as dull and cramp-like in nature and located in the epigastric region. This can be attributed to the lack of energy and nutritional support from decreased blood flow to the mesenteric vessels. This lack of nutritional support can lead to failure of smooth muscle relaxation that intensifies the cramping experienced.3–5
Patients will also complain of progressive involuntary weight loss which is attributed to “food aversion, food fear” due to anticipation of postprandial pain. The intensified abdominal pain after eating leads patients to associate the pain with eating and will modify their oral intake in order to prevent as much abdominal pain as possible. The modified diet will preferentially include liquids. Not uncommonly the patient ...