Right gastric artery

The right gastric artery is a small but important artery that supplies blood to the lower part of the stomach, particularly along the lesser curvature. It typically arises from the proper hepatic artery, a branch of the common hepatic artery, which is part of the celiac trunk’s vascular system.

Location

The right gastric artery is located in the upper abdomen, where it originates from the proper hepatic artery. It descends toward the stomach, running along the lesser curvature of the stomach. As it courses along this curvature, it anastomoses with the left gastric artery, which arises from the celiac trunk. The right gastric artery supplies blood to the lesser curvature, including parts of the stomach’s body and pylorus. It runs within the layers of the lesser omentum, which connects the stomach to the liver.

Structure and Anatomy

Origin

The right gastric artery typically arises from the proper hepatic artery, which is a branch of the common hepatic artery. The common hepatic artery originates from the celiac trunk, a major branch of the abdominal aorta. In some cases, the right gastric artery can also originate directly from the common hepatic artery or, less commonly, from other nearby vessels such as the gastroduodenal artery.

Course

After originating from the proper hepatic artery, the right gastric artery travels downward toward the lesser curvature of the stomach. It runs within the lesser omentum, a double-layered fold of peritoneum that connects the lesser curvature of the stomach to the liver. The artery follows the lesser curvature from the right side, traveling from the pyloric region of the stomach toward the middle of the lesser curvature.

As it moves along the lesser curvature, the right gastric artery supplies branches to the anterior and posterior surfaces of the stomach, particularly in the area of the body and pylorus.

Branches

The right gastric artery gives off several small branches as it courses along the stomach. These branches supply blood to the anterior and posterior surfaces of the stomach along the lesser curvature. The specific branches include:

• Gastric branches: These branches provide blood to the stomach’s muscular and mucosal layers, particularly along the lower part of the lesser curvature.
• Pyloric branches: These small branches extend toward the pyloric region of the stomach, supplying the muscular layers involved in the passage of food from the stomach into the duodenum.

Anastomosis

The right gastric artery forms an important anastomosis with the left gastric artery, which arises from the celiac trunk. This anastomosis occurs along the lesser curvature of the stomach, near the middle of its length. The left gastric artery supplies the upper portion of the stomach and descends along the lesser curvature, meeting the right gastric artery.

This anastomotic connection ensures that the lesser curvature of the stomach receives a continuous blood supply from both the right and left gastric arteries. The anastomosis also provides a degree of redundancy, ensuring that blood flow to the stomach is maintained even if one of the arteries is compromised.

Relations

• Anteriorly: The right gastric artery is covered by the peritoneum and lies close to the liver’s inferior surface as it courses toward the stomach. It is situated within the lesser omentum, a peritoneal fold between the liver and stomach.
• Posteriorly: Behind the right gastric artery are the structures of the hepatoduodenal ligament, including the portal vein and bile duct. The artery is also in close relation to the pancreas, which lies posterior to the stomach.
• Medially: Medially, the artery is related to the pyloric region of the stomach and the first part of the duodenum. It runs along the medial side of the stomach’s lesser curvature, where it anastomoses with the left gastric artery.
• Laterally: Lateral to the artery is the body of the stomach, which it supplies via small gastric branches.

Length and Diameter

The right gastric artery is a relatively small artery, both in length and diameter. Its course from the proper hepatic artery to the lesser curvature of the stomach is usually short, spanning just a few centimeters. Its diameter is also small compared to larger arteries like the left gastric or gastroduodenal arteries, reflecting its role in supplying a localized area of the stomach.

Termination

The right gastric artery terminates by forming an anastomosis with the left gastric artery along the middle of the lesser curvature of the stomach. From here, the blood continues to flow through both arteries to supply the stomach’s lesser curvature and its associated regions. The artery’s smaller branches continue to supply the muscular and mucosal layers of the stomach, particularly in the pyloric region and the lower body of the stomach.

Anatomical Variations

Anatomical variations in the right gastric artery are not uncommon. These variations can include:

• Origin from the common hepatic artery: Instead of originating from the proper hepatic artery, the right gastric artery may sometimes arise directly from the common hepatic artery.
• Origin from the gastroduodenal artery: In rare cases, the right gastric artery may originate from the gastroduodenal artery, which branches off the common hepatic artery and supplies the stomach and duodenum.
• Absent right gastric artery: In some individuals, the right gastric artery may be absent, with the lesser curvature receiving its blood supply entirely from the left gastric artery.

Function

The right gastric artery plays a vital role in supplying blood to the lesser curvature of the stomach, particularly the lower regions, including the body and pylorus. Its primary function is to provide oxygen and nutrients to the stomach tissues, supporting key physiological processes such as digestion, peristalsis, and mucosal protection. Below is a detailed breakdown of the artery’s specific functions.

Blood Supply to the Lesser Curvature of the Stomach

The right gastric artery provides oxygenated blood to the tissues along the lesser curvature of the stomach, including the mucosa, submucosa, and muscular layers:

• Mucosal Layer: The gastric mucosa secretes mucus, bicarbonate, and gastric juices, including hydrochloric acid and digestive enzymes. The blood supply from the right gastric artery ensures that the cells responsible for these secretions receive the oxygen and nutrients they need to maintain a healthy and functional mucosal lining.
• Muscular Layer: The smooth muscle in the stomach wall is responsible for peristalsis, the coordinated contractions that mix and move food through the digestive system. The right gastric artery supplies blood to these muscle layers, providing the energy required for peristaltic movements, especially in the lower part of the stomach, where food is mixed and pushed toward the pylorus and duodenum.

Support for Gastric Acid and Digestive Enzyme Secretion

The right gastric artery supplies blood to the gastric glands within the mucosal layer of the stomach, which are responsible for secreting gastric acid (hydrochloric acid) and digestive enzymes such as pepsin. This function is crucial for:

• Acid Production: The parietal cells in the stomach produce hydrochloric acid, which helps break down food and creates an acidic environment for enzyme activity. The blood flow provided by the right gastric artery delivers oxygen and nutrients to these cells, enabling them to continue producing acid.
• Enzyme Secretion: Pepsinogen, secreted by chief cells, is converted to pepsin in the acidic environment of the stomach. This enzyme is essential for protein digestion. The right gastric artery ensures that these enzyme-producing cells are nourished and functional, supporting the digestive process.

Oxygen and Nutrient Delivery

The primary function of the right gastric artery, like all arteries, is to deliver oxygenated blood and nutrients to the tissues it supplies. This function is essential for:

• Cellular Metabolism: The epithelial cells of the gastric mucosa, as well as the smooth muscle cells in the stomach wall, rely on a constant supply of oxygen to carry out cellular respiration, which generates the energy needed for their activities. The right gastric artery supports these processes, ensuring that the stomach cells receive the oxygen they need to function properly.
• Tissue Repair and Regeneration: The stomach lining is constantly exposed to digestive enzymes and acidic gastric juices, which can cause damage over time. The blood supplied by the right gastric artery provides the resources needed for the repair and regeneration of these tissues, helping to maintain the stomach’s integrity and functionality.

Blood Supply to the Pylorus

The right gastric artery plays an essential role in supplying blood to the pyloric region of the stomach. The pylorus is the region where the stomach connects to the duodenum and regulates the passage of partially digested food (chyme) into the small intestine. The blood supply from the right gastric artery supports:

• Pyloric Sphincter Function: The pyloric sphincter is a ring of smooth muscle that controls the release of chyme into the duodenum. The smooth muscle fibers in this region rely on a continuous blood supply from the right gastric artery to perform their contractile function, ensuring that food is properly regulated as it exits the stomach.
• Coordination of Gastric Emptying: Blood flow to the pyloric region supports the coordinated muscular contractions necessary for gastric emptying, ensuring that food is passed from the stomach to the small intestine at the appropriate time for digestion.

Anastomotic Support for the Gastric Circulation

The right gastric artery contributes to the anastomotic network that supplies blood to the stomach. Its role in this network provides critical collateral circulation:

• Anastomosis with the Left Gastric Artery: The right gastric artery anastomoses with the left gastric artery along the lesser curvature of the stomach. This anastomosis ensures that the stomach receives blood from multiple sources, providing a safeguard against ischemia if one artery becomes obstructed or damaged. The anastomotic network helps maintain a consistent blood flow to the stomach tissues, even during variations in blood pressure or surgical interventions.
• Protection Against Ischemia: The anastomotic connections between the right and left gastric arteries help protect the stomach from ischemia (lack of blood flow). If blood flow is reduced in one artery, the other can compensate by providing blood to the same region, ensuring that the stomach continues to receive adequate oxygen and nutrients.

Clinical Significance

The right gastric artery is clinically significant due to its role in supplying blood to the lesser curvature of the stomach and its importance in various surgical procedures. During gastrectomy (partial or total removal of the stomach) or other gastric surgeries, the right gastric artery must be carefully identified and ligated to prevent excessive bleeding. Its anastomosis with the left gastric artery provides crucial collateral circulation, helping to maintain blood flow to the stomach even if one artery is compromised.

In cases of gastric ulcers along the lesser curvature, the right gastric artery may be involved. Damage to this artery from ulcer perforation can lead to significant bleeding, necessitating surgical intervention. Additionally, anatomical variations in the origin of the right gastric artery can affect surgical planning in procedures involving the stomach, liver, or bile ducts. Understanding its course and relation to other structures is essential to avoid complications during surgeries in the upper abdomen.