The splenic vein, also referred to as the lineal vein, is a blood vessel which carries blood from the spleen to the heart. The spleen is an organ of the lymphatic system of the body, which is responsible for maintaining fluid balance. The spleen, located under the ribs on the left side of the body and above the stomach, not only plays a vital role in fluid balance and infection control, it assists in the regulation of blood, both the quantity and the content, by destroying old or damaged blood cells.
This blood vessel is formed by the joining of several smaller vessels on the anterior surface of the spleen. The splenic vein then travels to the pancreas, a gland which produces and secretes several vital hormones such as insulin and digestive enzymes, in order to maintain the body’s homeostasis or balance. The splenic vein then unites with the superior mesenteric vein to form the portal vein. The portal vein is responsible for pumping blood out of the spleen and the gastrointestinal tract.
Problems can occur when there is a change in blood flow within the splenic vein. This can lead to portal hypertension, a condition in which increased pressure is created from a slowing or a blockage of the blood out of the spleen. The buildup of blood pressure can then cause a decrease in the amount of blood draining from the spleen and returning to the heart. This condition can be caused by problems with the liver, such as cirrhosis or scarring of the liver, which affects the merging blood vessels, or by such things as parasitic infections and blood clots.
A thrombosis, or blood clot, in the splenic vein or conjoining blood vessels can lead to a partial or complete occlusion or blockage of the normal flow of blood. The most common cause for this condition is chronic pancreatitis or inflammation of the pancreas, but it can also be caused by surgical procedures in and around the area of the splenic vein, lymphoma, or cancer of the lymphatic system or in the pancreas, and an occlusion in the portal vein. This slowing or stoppage of blood flow can disrupt the homeostasis of the body.
A blood clot which breaks free is called an embolism. An embolism can move through the blood vessels such as the splenic vein, causing a blockage of the flow of blood in another part of the body. This can be a life-threatening condition if the clot travels to the heart or lungs.