Arterial and Venous Blood Supply of the Stomach

The stomach, in human biology, is the portion of the ali­mentary canal that is richly supplied with blood vessels. Both the quantity of blood delivered to the stomach and the richness of the intramural gastric vascular anastomotic net­work are impressive. The large majority of the gastric blood supply is from the celiac axis via four named arteries. 

The left and right gastric arteries form an anastomotic arcade along the lesser curvature, and the right and left gastroepiploic arteries form an ar­cade along the greater gastric curvature. The consistently largest artery to the stomach in human biology is the left gastric artery. 

This artery usually arises directly from the celiac trunk and divides into an ascending and de­scending branch along the lesser gastric curvature. Approximately 15% of the time, the left gastric artery supplies an aberrant ves­sel, which travels in the gastrohepatic ligament (lesser omentum) to the left side of the liver. Rarely, this is the only arterial blood supply to this part of the liver, and inadvertent ligation may lead to clinically significant hepatic ischemia that could lad to hepatic injury or failure. 

The second largest artery to the stomach is usually the right gastroepiploic artery, which arises fairly consistently from the gastroduodenal artery behind the first portion of the duodenum. The left gastroepiploic artery arises from the splenic artery, and together with the right gastroepiploic artery, forms the rich gastroepiploic arcade along the greater curvature. The right gastric artery usually arises from the hepatic artery near the py­lorus and hepatoduodenal ligament, and runs proximally along the distal stomach. 

In the fundus along the proximal greater curvature, the short gastric arteries and veins arise from the splenic circulation. There also may be vascular branches to the proximal stomach from the phrenic circulation.

In human biology, the veins draining the stomach generally parallel the arteries. The left gastric or coronary vein and right gastric veins usually drain into the portal vein, though occasionally the coronary vein drains into the splenic vein. The right gastroepiploic vein drains into the superior mesenteric vein near the inferior border of the pancreatic neck, and the left gastroepiploic vein drains into the splenic vein.

The richness of the gastric blood supply and the extensive­ness of the anastomotic connections have some important clini­cal implications in human biology including: 

(1) erosion of a peptic ulcer or gastric cancer into a large perigastric vessel sometimes causes life-threatening hemorrhage; 

(2) because of the rich venous intercon­nections, a distal splenorenal shunt, which connects the distal end of the divided splenic vein to the side of the left renal vein, can ef­fectively decompress esophagogastric varices in patients with portal hypertension; and 

(3) if necessary, at least two of the four named gastric arteries may be occluded or ligated with impunity. 

This is done routinely when the stomach is mobilized and pedicellated on the right gastric and right gastroepiploic vessels to reach into the neck as an esophageal replacement.