Gross anatomy of the mesenteric vascular system
Three major arteries and two major veins compose the mesenteric circulation.
|• Celiac artery|
• Superior mesenteric artery (SMA)
• Inferior mesenteric artery (IMA)
|• Superior mesenteric vein (SMV)|
• Inferior mesenteric vein (IMV)
The connection of major arteries and veins via capillaries, arterioles, and venules is known as the splanchnic circulation.
The celiac artery provides blood to the stomach, proximal duodenum, part of the pancreas, spleen, liver, gallbladder, and biliary tree.
The SMA provides blood to the rest of the duodenum and pancreas, the entire small intestine, and the large intestine up to the splenic flexure.
The IMA supplies the remainder of the colon and rectum, with the latter receiving dual blood supply from internal iliac arteries as well.
The IMV drains into the splenic vein, and the SMV and splenic vein anastomose to form the portal vein.
Mirroring the arterial blood supply, there is dual venous drainage of the rectum into the systemic system through the inferior vena cava via the internal iliac veins and through the IMV to the portal circulation.