Learning Objectives

• Identify the anatomical origin of the coeliac trunk at the T12 level.
• Master the three primary branches: Left Gastric, Splenic, and Common Hepatic arteries.
• Describe the anastomotic networks of the stomach and the pancreaticoduodenal arcade.
• Correlate clinical pathologies such as peptic ulcer erosion and Median Arcuate Ligament Syndrome.

Anatomical Position

The coeliac trunk is the first major unpaired visceral branch of the abdominal aorta. It is a short, thick vessel (~1 cm long) that arises anteriorly at the T12 vertebral level, immediately as the aorta passes through the aortic hiatus of the diaphragm.

The Three Primary Branches

The trunk quickly trifurcates into three vessels that supply the foregut structures (stomach, spleen, liver, gallbladder, abdominal esophagus, pancreas, and superior duodenum).

I. Left Gastric Artery (Smallest)

• Course: Ascends to the esophageal opening of the diaphragm, then runs along the lesser curvature of the stomach.
• Branches: Oesophageal branches.
• Anastomosis: Right gastric artery.

II. Splenic Artery (Most Tortuous)

• Course: Runs a wavy path along the superior border of the pancreas within the splenorenal ligament.
• Key Branches:
  • Short Gastrics: Supply the gastric fundus.
  • Left Gastroepiploic: Runs along the greater curvature.
  • Pancreatic Branches: Supply the body and tail of the pancreas.

III. Common Hepatic Artery

The only branch is directed to the right. It divides into two terminal vessels:

1. Proper Hepatic Artery: Ascends in the hepatoduodenal ligament. Gives off the Right Gastric and Cystic arteries (supplying the gallbladder) before splitting into the right and Left Hepatic arteries.
2. Gastroduodenal Artery: Descends posterior to the 1st part of the duodenum. Gives off the Right Gastroepiploic and Superior Pancreaticoduodenal arteries.

Key Anastomoses

The Gastric Arcade

The stomach has a redundant blood supply to protect against ischemia:

• Lesser Curvature: Left Gastric (Coeliac) + Right Gastric (Proper Hepatic).
• Greater Curvature: Left Gastroepiploic (Splenic) + Right Gastroepiploic (Gastroduodenal).

The Pancreaticoduodenal Arcade

This network marks the transition from Foregut to Midgut:

• Superior Pancreaticoduodenal (from Coeliac Trunk/Gastroduodenal).
• Inferior Pancreaticoduodenal (from the Superior Mesenteric Artery).

Clinical Relevance

• Eroding Peptic Ulcers: A posterior duodenal ulcer can erode into the Gastroduodenal Artery, leading to life-threatening hemorrhage.
• Median Arcuate Ligament Syndrome: Compression of the coeliac trunk by the diaphragm’s fibrous bridge. It presents as postprandial abdominal pain and weight loss (intestinal angina).
• Splenic Artery Aneurysm: The most common visceral aneurysm. Risk factors include multiparity and portal hypertension.

Activity