The cystic artery is a small artery that supplies the gallbladder, common hepatic duct, cystic duct and the proximal part of the common bile duct. It usually arises from the right hepatic artery, a branch of the proper hepatic artery.
It lies in the cystohepatic triangle (of Calot), an anatomical space whose borders are formed by the cystic duct, the common hepatic duct and the inferior surface of the liver. Calot’s triangle is an important landmark used to locate and ligate the cystic artery during a cholecystectomy.
This article will discuss the anatomy and function of the cystic artery.
|Origin||Proper hepatic artery|
|Branches||Superficial and deep branches|
|Supply||Gallbladder, common hepatic duct, cystic duct, proximal part of the common bile duct|
The cystic artery usually arises from the right hepatic artery within the cystohepatic triangle (of Calot), although its origin can be highly variable. The cystohepatic triangle is bounded by the cystic duct on the right side, the common hepatic duct on the left side and the inferior surface of the liver above.
After its origin point, the cystic artery usually courses posterolateral to the common hepatic duct and anterior to the cystic duct towards the neck of the gallbladder.
Branches and supply
Upon reaching the superior aspect of the neck of the gallbladder, the cystic artery splits into superficial and deep branches, that anastomose over the surface of the body and fundus of the gallbladder. The superficial branch of the cystic artery supplies the inferior aspect of the body of the gallbladder, while the deep branch supplies its superior aspect. Additionally, the cystic artery gives off several fine branches, known as Calot’s branches, that supply blood to the common hepatic duct, cystic duct, and the proximal part of the common bile duct.
Variations in origin and course of the cystic artery are quite common, occurring in approximately 15-25% of the general population.
- Instead arising from the right hepatic artery, the cystic artery may arise from the common hepatic, left hepatic artery, gastroduodenal or other arteries.
- Superficial and deep branches of the cystic artery can sometimes differ in origin, an occurrence known as double cystic artery.
- Instead of its typical posterior course, the cystic artery may run anterior to the cystic and bile ducts.