Left hepatic artery

The left hepatic artery (LHA) is formed when the proper hepatic artery (PHA) bifurcates. The hepatic arteries provide 25% of the blood supply and 50% of the oxygen supply to the liver.

Gross anatomy

The proper hepatic artery bifurcates into the left and right hepatic arteries at or before reaching the porta hepatis. These are end arteries and supply the left and the right halves of the liver respectively. The left hepatic artery runs vertically towards the umbilical fissure and supplies segments 1, 2 and 3. It usually gives off a middle hepatic artery branch that runs towards the right side of the umbilical fissure that supplies segments 4a and 4b .

Within the liver, the left hepatic artery divides into:

• medial segmental branch
• lateral segmental branch

NB: the hepatic segments were originally numbered by Roman numerals I to VIII, but the Arabic numerals 1 to 8 are now preferred

Variant anatomy

• a replaced LHA may arise from other branches instead of the PHA:
  • left gastric artery (most common)
  • celiac trunk
  • gastroduodenal artery
  • superior mesenteric artery
  • splenic artery
  • abdominal aorta
• an accessory LHA may be present and arise from the:
  • left gastric artery
  • celiac trunk
  • right hepatic artery
  • superior mesenteric artery
• it may give rise to a falciform artery