From the Guidelines
The best approach to rule out mesenteric ischemia is a triple-phase CT of the abdomen and pelvis, including non-contrast, arterial, and portal venous phases, as it provides detailed visualization of the mesenteric vessels and can identify the underlying cause of ischemia, evaluate for possible bowel complications, and exclude other potential diagnoses of acute abdominal pain. This recommendation is based on the most recent and highest quality study, which emphasizes the importance of a comprehensive imaging evaluation in the diagnosis of mesenteric ischemia 1. The use of CT angiography (CTA) with intravenous contrast is also supported by previous guidelines, which highlight its high sensitivity and specificity in identifying arterial occlusions, stenosis, or venous thrombosis 1.
Key Considerations
- CT of the abdomen and pelvis should be performed in the non-contrast, arterial, and portal venous phases to evaluate the underlying cause of ischemia and exclude other potential diagnoses.
- MR angiography (MRA) can be considered as an alternative for patients with contraindications to CT contrast, but it is limited in its ability to evaluate for ischemic bowel changes.
- Laboratory tests, including lactate, white blood cell count, and D-dimer, may support the diagnosis but are not specific enough to rule out mesenteric ischemia.
- Early diagnosis is critical, as mortality rates increase significantly with delayed treatment, particularly in patients with risk factors such as atrial fibrillation, recent myocardial infarction, or hypercoagulable states who present with severe abdominal pain disproportionate to physical examination findings.
Imaging Evaluation
- A triple-phase CT of the abdomen and pelvis is the preferred imaging modality for diagnosing mesenteric ischemia, as it provides detailed visualization of the mesenteric vessels and can identify the underlying cause of ischemia.
- Conventional catheter angiography may be necessary if CTA findings are equivocal but clinical suspicion remains high, and it also offers therapeutic options such as intra-arterial vasodilators or thrombectomy.
From the Research
Diagnostic Approaches for Mesenteric Ischemia
To rule out mesenteric ischemia, several diagnostic approaches can be considered:
- Computed Tomography (CT) with intravenous contrast enhancement is a recommended initial test, as it is fast, widely available, and noninvasive 2, 3, 4, 5.
- CT angiography can help identify the extent of mesenteric ischemia and guide revascularization 4, 5.
- Catheter-based angiography is considered the reference standard and enables diagnosis and treatment, but its use may be limited due to its invasive nature 3.
Imaging Modalities
The following imaging modalities can be used to evaluate patients with suspected mesenteric ischemia:
- Abdominal radiographs and ultrasound have a limited role in diagnosing mesenteric ischemia, but may be used as initial tests to diagnose more common pathologies 3.
- Contrast-enhanced computed tomography is a first-line test in many patients due to its speed, availability, and noninvasive nature 3, 5.
Treatment Options
Treatment options for mesenteric ischemia include:
- Endovascular recanalization and stenting, which has become an important alternative, especially in patients with acute and chronic thrombotic superior mesenteric artery (SMA) occlusion 2.
- Aspiration embolectomy, thrombolysis, and open surgical embolectomy, followed by on-table angiography, are treatment options for embolic SMA occlusion 2.
- Damage-control surgery is recommended after intestinal revascularization to reduce bowel morbidity and mortality 2.