hepatic artery

The common hepatic artery arises from the celiac trunk (along with the left gastric and splenic arteries) and travels within the hepatoduodenal ligament as part of the portal triad, alongside the portal vein (posterior) and common bile duct (anterior, to the right). It gives off the gastroduodenal artery before becoming the proper hepatic artery, which then divides into right and left hepatic arteries supplying the corresponding liver lobes. The right hepatic artery typically gives rise to the cystic artery supplying the gallbladder, forming the anatomical relationships critical in Calot's triangle during cholecystectomy.

Clinically, hepatic artery anatomy is highly variable—variants include a replaced right hepatic artery arising from the superior mesenteric artery (SMA) and a replaced left hepatic artery from the left gastric artery, both important to identify preoperatively to avoid injury during hepatobiliary surgery or transplantation.

The liver has a dual blood supply: the hepatic artery provides oxygen-rich blood (~25% of flow, ~50% of oxygen delivery), while the portal vein delivers nutrient-rich, partially deoxygenated blood from the GI tract and spleen (~75% of flow). This dual supply provides some protection against ischemia but makes the liver vulnerable to shock states affecting both systemic and portal circulation.

Hepatic artery thrombosis is a serious complication after liver transplantation, potentially leading to graft failure, biliary ischemia, and necessitating re-transplantation, since the biliary tree is exclusively supplied by the hepatic artery (unlike the liver parenchyma). The hepatic artery is also the target vessel for transarterial chemoembolization (TACE) and radioembolization (TARE) in treating unresectable hepatocellular carcinoma, exploiting the fact that HCC tumors derive most of their blood supply from the hepatic artery rather than the portal vein, unlike normal liver parenchyma.