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In about 20% of individuals there is an aberrant left hepatic artery which usually arises from the left gastric artery. Half the time, such an artery replaces the normal left hepatic, and the other half the vessel is accessory. Such a vessel is a hazard for hemorrhage when the gastrohepatic ligament (lesser omentum) is divided as in this case or during fundoplication. If the vessel is accessory one may get away with dividing it for exposure, but if it is a replacement, division may partially devascularize a portion of the liver. Even so, there may be no serious consequences since the liver receives 60% of its blood flow from the portal system.
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