What are the branches of the abdominal aorta?

Branches of the Abdominal Aorta

The abdominal aorta has three major ventral branches (celiac trunk, superior mesenteric artery, and inferior mesenteric artery), three major lateral paired branches (suprarenal, renal, and gonadal arteries), and multiple paired parietal branches including the inferior phrenic, lumbar, and median sacral arteries.

Anatomical Classification of Abdominal Aortic Branches

Ventral (Anterior) Branches

• Celiac Trunk: The first major branch arising at the level of T12-L1

  • Divides into three branches:
    • Left gastric artery
    • Splenic artery
    • Common hepatic artery (further divides into proper hepatic and gastroduodenal arteries)

• Superior Mesenteric Artery (SMA): Arises about 1 cm below the celiac trunk at L1

  • Branches include:
    • Inferior pancreaticoduodenal arteries
    • Jejunal and ileal branches
    • Ileocolic artery
    • Right colic artery
    • Middle colic artery

• Inferior Mesenteric Artery (IMA): Originates at the level of L3

  • Branches include:
    • Left colic artery
    • Sigmoid arteries
    • Superior rectal artery

Lateral Paired Branches

• Suprarenal (Adrenal) Arteries: Small paired vessels to the adrenal glands
• Renal Arteries: Large paired vessels at the level of L1-L2
• Gonadal Arteries:
  • Testicular arteries in males
  • Ovarian arteries in females

Posterior/Parietal Branches

• Inferior Phrenic Arteries: Supply the diaphragm
• Lumbar Arteries: Four to five pairs supplying the posterior abdominal wall
• Median Sacral Artery: Small unpaired vessel arising from the posterior aspect of the aortic bifurcation

Clinical Significance

Vascular Pathologies

• The abdominal aorta is a common site for aneurysm formation, particularly in the infrarenal segment 1
• Abdominal aortic aneurysms typically occur below the renal arteries and can extend to involve the iliac arteries 2
• Stenosis of the abdominal aorta can affect young patients and is often associated with renal artery lesions 3

Anatomical Variations

• Variations in the branching pattern of the abdominal aorta are common and clinically significant 4
• Common variations include:
  • Accessory renal arteries (20-30% of individuals)
  • Variations in the origin of the inferior phrenic arteries
  • Variations in gonadal artery origin
  • Celiac trunk variations (including hepatic artery anomalies)

Surgical Considerations

• Knowledge of abdominal aortic branches is critical for:

  • Vascular and transplant surgery
  • Endovascular procedures
  • Abdominal trauma management
  • Oncologic resections

• When treating thoracoabdominal aortic aneurysms with endografts, preservation of blood flow to mesenteric vessels is essential to prevent mesenteric ischemia (approximately 3% risk) 2

• During endovascular procedures, both the celiac trunk and superior mesenteric artery may require revascularization to maintain adequate blood flow to abdominal organs 2

Imaging of the Abdominal Aorta and Its Branches

• CT Angiography (CTA): Gold standard for detailed evaluation of the abdominal aorta and its branches 2

  • Provides excellent visualization of vascular anatomy
  • Allows for 3D reconstruction and multiplanar reformatting

• Ultrasound: Useful for screening and surveillance of abdominal aortic aneurysms 1

  • Non-invasive and does not require contrast
  • Limited in visualizing some branches and retroperitoneal structures

• MR Angiography (MRA): Alternative when CTA is contraindicated 2

  • Avoids radiation exposure
  • Useful for patients with renal dysfunction

Common Pathologies Affecting Abdominal Aortic Branches

• Atherosclerosis: Can affect any branch, commonly the renal arteries and aortic bifurcation
• Aneurysms: Most common in the infrarenal segment 1
• Dissection: Can extend from thoracic aorta or originate in abdominal aorta
• Thromboembolism: Can occlude distal branches causing end-organ ischemia
• Vasculitis: Inflammatory conditions affecting the aorta and its branches

Understanding the anatomy of abdominal aortic branches is essential for accurate diagnosis and management of vascular pathologies in this region, particularly for planning surgical or endovascular interventions.