Appendicular artery

At a glance

English

Appendicular artery

Latin (TA2)

Arteria appendicularis

System

Artery

Region

Trunk

Side

Single, on the midline

About the appendicular artery

The appendicular artery, also called the appendiceal artery, is the vessel of the vermiform appendix. It is part of the superior mesenteric system. In most people it comes from the lower, terminal division of the ileocolic artery; less often it arises from the posterior caecal artery or from an ileal branch.

From its origin it passes down behind the last part of the ileum, close to the ileocaecal junction, and enters the mesoappendix, the small triangular fold of peritoneum that attaches the appendix to the mesentery of the terminal ileum. Within this fold it runs towards the tip of the appendix close to the free edge of the mesoappendix, sending short branches to the wall of the organ along the way. An accessory appendicular artery is found in some people, usually supplying the base.

The artery supplies the whole appendix and is effectively an end artery: it has few useful connections with the caecal arteries. Venous blood returns through the appendicular vein to the ileocolic vein and on to the superior mesenteric and portal veins, while lymph drains to the ileocolic nodes.

This end-artery arrangement explains why an inflamed appendix can develop gangrene and perforate once swelling compresses or clots the vessel, often starting at the tip, which lies furthest from the origin. During appendicectomy, open or laparoscopic, the artery is found in the mesoappendix and is tied, clipped or sealed before the appendix is removed; failure to secure it is a cause of bleeding after the operation.

Course and supply

Arises from

Arises most often from the ileocolic artery's inferior (terminal) division; less commonly from the posterior caecal artery or an ileal branch.

Ends in

Ends near the tip of the appendix after running along the free edge of its peritoneal fold.

Supplies

Supplies the vermiform appendix.