Visceral Artery Insufficiency

Key Features

Essentials of Diagnosis

• Severe postprandial abdominal pain

• Weight loss with a "fear of eating"

• Acute mesenteric ischemia: severe abdominal pain yet minimal findings on physical examination

General Considerations

• Acute mesenteric artery insufficiency results from

  • Embolic occlusion or primary thrombosis of at least one major mesenteric vessel

  • Nonocclusive mesenteric vascular insufficiency, which is generally seen in patients with low flow states, such as heart failure, or hypotension

• Chronic mesenteric ischemia

  • Also called intestinal angina

  • Occurs when increased flow demands during feeding are not met resulting in abdominal pain

  • Because of the rich collateral mesenteric network, at least two of the three major visceral vessels (celiac, superior mesenteric, inferior mesenteric arteries) are affected before symptoms develop

• Ischemic colitis

  • A variant of mesenteric ischemia

  • Usually occurs in the distribution of the inferior mesenteric artery

  • The intestinal mucosa is the most sensitive to ischemia and will slough if under perfused

Demographics

• Patients with chronic mesenteric ischemia are generally over age 45 years

Clinical Findings

Symptoms and Signs

• Acute mesenteric ischemia

  • Severe, steady diffuse abdominal pain with absence of focal tenderness or distention

  • Pain "out of proportion" to physical findings occurs because ischemia initially is mucosal and does not impact the peritoneum until transmural ischemia inflames the peritoneal lining

  • Abdominal distention may aid in the diagnosis

• Chronic mesenteric ischemia

  • Evidence of atherosclerosis in other vascular beds

  • Epigastric or periumbilical postprandial pain lasting 1–3 hours

  • Weight loss

• Ischemic colitis

  • Left lower quadrant pain and tenderness

  • Abdominal cramping

  • Mild diarrhea

  • Rectal discharge will appear mucus-like or bloody and should prompt further evaluation

Differential Diagnosis

• Peptic ulcer disease

• Inflammatory bowel disease

• Perforated abdominal abscess

• Sepsis

• Diverticulitis

Diagnosis

Laboratory Tests

• Acute mesenteric ischemia: high white blood cell count, lactic acidosis, hypotension

• Obtain complete blood count

• Arterial blood gas if lactic acidosis is suspected

Imaging Studies

• Contrast enhanced CT is highly accurate at determining the presence of ischemic intestine

• CT angiography or magnetic resonance angiography can demonstrate narrowing of proximal visceral vessels in patients with acute or chronic mesenteric ischemia

• Angiography shows typical "pruned tree" appearance of distal visceral vascular bed in acute mesenteric ischemia from a nonocclusive low flow state

• Ultrasonography may show proximal obstructing lesions

Diagnostic Procedures

• In patients with ischemic colitis, flexible sigmoidoscopy should be performed to assess the grade of ischemia that occurs most often in watershed areas such as the rectal sigmoid and splenic flexure

Treatment

Medications