Left Colic Artery

arteria colica sinistra

The left colic artery is the first branch of the inferior mesenteric artery, ascending in the left retroperitoneum to supply the descending colon and the distal transverse colon. It divides into ascending and descending branches that anastomose with the middle colic artery (from the SMA) superiorly and the sigmoid arteries inferiorly, contributing to the marginal artery of Drummond along the mesocolic border.

Region: Abdomen

Clinical Relevance

Clinical Notes

The left colic artery forms the critical anastomotic link at Griffith point between the middle colic (SMA territory) and the inferior mesenteric artery territory at the splenic flexure. This is the most common watershed zone of the colon, susceptible to ischaemia during hypotensive episodes and after aortic surgery when IMA flow is disrupted. In left colectomy and sigmoid resection, the left colic artery is ligated at its origin from the IMA or more distally depending on oncological requirements, with assessment of splenic flexure perfusion before anastomosis.

Pathology

Common Injuries & Conditions

Griffith Point Colon Ischaemia

The splenic flexure watershed between left colic and middle colic territories is the most vulnerable segment during aortic aneurysm repair, hypotension, or IMA ligation, producing ischaemic colitis with bloody diarrhoea and abdominal pain requiring urgent colonoscopy and potentially bowel resection.