Between 30 and 40 percent of individuals have non-traditional blood circulatory systems in their livers. The most common difference from standard anatomy is an extra artery.

If the additional artery were associated with the left hepatic artery, it would be referred to as the accessory left hepatic artery. If there was an additional artery, but one of the primary hepatic arteries was not present, it would be referred to as the replaced hepatic artery, of the left or the right.

Injury to the arteries of the liver (known as hepatic arterial injury) is a well-documented consequence of trauma. The presence of unusual or undocumented vascular structures in the liver is an additional risk factor for hepatic arterial injuries that are related to surgical procedures, such as the laparoscopic cholecystectomy.

Technologies capable of looking at vascular structures in the liver are magnetic resonance imaging, angiography, and CT scan. Because of the potential for iatrogenic injury, the vascular structures of the liver should be thoroughly studied and mapped to locate unusual vessels such as an accessory left hepatic artery before any surgical procedure impacting the liver.