From the Guidelines
Mesenteric ischemia is a life-threatening condition that requires immediate medical attention, characterized by reduced blood flow to the intestines, leading to tissue damage and potentially fatal complications, with symptoms including severe abdominal pain, nausea, vomiting, and bloody diarrhea, and diagnosis involving CT angiography as the preferred initial imaging study. The condition presents in acute and chronic forms, with acute mesenteric ischemia requiring emergency intervention 1. Symptoms typically include severe abdominal pain disproportionate to physical findings, nausea, vomiting, and in later stages, bloody diarrhea. The underlying causes of mesenteric ischemia include arterial occlusion (embolism or thrombosis), non-occlusive causes (low cardiac output), or venous thrombosis, all leading to intestinal hypoperfusion, inflammation, and potential necrosis if not promptly addressed 1.
Key Points
- Mesenteric ischemia has a high mortality rate, ranging between 30% to 90% in acute settings despite advances in treatment options 1
- The etiology of ischemia may vary from arterial occlusion, venous thrombosis, or vasoconstriction, with higher prevalence in the elderly population and nonspecific hypercoagulable states, portal hypertension, and recent surgery contributing to the high mortality rate 1
- Chronic mesenteric ischemia occurs because of occlusive or stenotic atherosclerotic disease and most commonly involves at least 2 or 3 main vessels, and is more prevalent in the elderly population and in patients with major risk factors for atherosclerosis, such as hypertension, hyperlipidemia, and smoking history 1
- Diagnosis involves CT angiography, which is the preferred initial imaging study, and treatment depends on the cause but generally includes fluid resuscitation, antibiotics, anticoagulation with heparin, and often surgical intervention 1
Treatment and Management
- Revascularization procedures may include embolectomy, bypass surgery, or endovascular techniques like angioplasty and stenting
- For chronic mesenteric ischemia, lifestyle modifications and management of cardiovascular risk factors are important alongside potential revascularization
- The goal of treatment is to restore blood flow to the affected area, prevent further tissue damage, and manage symptoms and complications.
From the Research
Causes of Mesenteric Ischemia
- Mesenteric ischemia is caused by a critical reduction in intestinal blood flow that frequently results in bowel necrosis and is associated with a high mortality 2, 3
- The condition can be caused by an arterial or venous occlusion, a vasospasm secondary to low-flow states in intensive care patients, aortic clamping during vascular surgery or intestinal transplantation 4
- Superior mesenteric artery embolism is the most common cause of acute mesenteric ischemia 5
Symptoms of Mesenteric Ischemia
- Acute mesenteric ischemia is characterized by sudden onset of abdominal pain 5
- A benign abdominal exam may be observed prior to bowel infarction 5
- Chronic mesenteric ischemia usually presents with post-prandial pain and weight loss 5
Diagnosis and Treatment
- Conventional angiography and computed tomography angiography are the cornerstones of diagnosis 5
- Correction of predisposing conditions, volume resuscitation, and antibiotic treatment are standard treatments for acute mesenteric ischemia 5
- Surgery is mandated in the setting of peritoneal signs 5
- Intra-arterial vasodilators are used routinely in the treatment of non-occlusive mesenteric ischemia and also are advocated in the treatment of occlusive acute mesenteric ischemia to decrease associated vasospasm 5
- Thrombolytics have been used on a limited basis to treat occlusive acute mesenteric ischemia 5
- Microcatheter-directed thrombolysis using recombinant tissue plasminogen activator is a potential treatment option for acute superior mesenteric artery embolism 6