Gastroduodenal vein

The gastroduodenal vein (vena gastroduodenalis ) is a short, thick venous trunk that arises as a tributary of the portal venous system and is the confluence of the right gastroepiploic vein and cranial pancreaticoduodenal vein, and in some species, the right gastric vein, . It is primarily responsible for the drainage of blood from the pyloric region of the stomach and the proximal portion of the duodenum, along with portions of the greater omentum and pancreas in domestic mammals.

Origin and Course

The gastroduodenal vein typically originates from the confluence of two or more smaller veins: the right gastroepiploic vein (which drains the greater curvature of the stomach) and the cranial pancreaticoduodenal vein (which drains the cranial part of the duodenum and adjacent pancreas). These veins converge dorsal to the pyloric region of the stomach.

From its origin, the gastroduodenal vein courses dorsally and cranially, often traveling in close association with the gastroduodenal artery, posterior to the pylorus. It runs medial to the descending duodenum and contributes to the portal vein as one of its important tributaries. The vein enters the portal system typically at or just before the confluence of the cranial mesenteric and splenic veins, although there is variability among species and even individuals.

Tributaries

The main tributaries of the gastroduodenal vein include:

• Right gastroepiploic vein (vena gastroepiploica dextra): Drains blood from the greater curvature of the stomach and greater omentum.

• Cranial pancreaticoduodenal vein (vena pancreaticoduodenalis cranialis): Drains the cranial duodenal flexure and the right lobe of the pancreas.

• In some animals, minor tributaries from the pyloric antrum and omental branches may contribute.

• In dog and cat, the right gastric vein may drain in the gastroduodenal vein.

Species Differences

• Canine: The gastroduodenal vein is well-developed and frequently forms an important component of the portal drainage. It is often visible during surgical procedures involving the hepatoduodenal ligament.

• Feline: Similar to the canine, although smaller in absolute terms. The configuration of tributaries may be slightly different due to the more compact abdominal conformation.

• Equine: The gastroduodenal vein is less prominent in surgical anatomy, due to the more dorsal location of the pylorus and duodenum. It still drains into the portal vein, but may do so at a more variable site.

• Ruminants (bovine, ovine, caprine): The stomach's compartmentalization alters the pattern of venous drainage. The vein still arises from the region of the abomasum and duodenum, but additional tributaries from the omasum or pyloric region may be present.

• Porcine: Shows close resemblance to the canine model, with a prominent contribution to the portal vein.