The key difference between hepatic vein and portal vein is that hepatic vein transports the blood away from the liver into the inferior vena cava while portal vein transports blood from the gastrointestinal tract, gall bladder, pancreas, and spleen into the liver.
Blood vessels circulate blood throughout the body. They deliver oxygen to vital organs and tissues in the body and remove waste products from these organs. There are three types of blood vessels: arteries (transport blood away from the heart), veins (transport blood back toward the heart), and capillaries (connect arteries and veins). Hepatic vein and portal vein are two different types of veins associated with the liver.
CONTENTS
1. Overview and Key Difference
2. What is Hepatic Vein
3. What is Portal Vein
4. Similarities – Hepatic Vein and Portal Vein
5. Hepatic Vein vs Portal Vein in Tabular Form
6. Summary – Hepatic Vein vs Portal Vein
What is Hepatic Vein?
Hepatic vein carries blood away from the liver into the inferior vena cava. Hepatic veins are of two types as upper and lower hepatic veins. There are three large upper hepatic veins that drain from three major parts of the liver. There are also about 6 to 20 lower hepatic veins draining from the right lobe and the caudate lobe of the liver. All these hepatic veins are valveless. They lack venous valves. All these hepatic veins transport low-oxygen blood from the liver back to the heart. A blockage in one of these hepatic veins may damage the liver.
Budd-Chiari syndrome is a condition that occurs due to an obstruction or narrowing of a hepatic vein by a blood clot. As a result, three types of major symptoms, including abdominal pain, ascites, and liver enlargement, can be seen. Budd-Chiari syndrome occurs in 1 out of a million individuals, and it can be fulminant, acute, chronic, or asymptomatic. Sometimes, other factors like radiation, certain chemotherapy drugs, and birth control pills can also block these hepatic veins. The treatment options for hepatic vein blockages include surgery and liver transplantation.
What is Portal Vein?
Portal vein, also called the hepatic portal vein, is the vein that carries blood away from the gastrointestinal tract, gall bladder, pancreas, and spleen to the liver. The blood is rich in nutrients and toxins extracted from digested contents. The liver can process this nutrient-rich blood and filter out any toxins present in the blood before sending the blood into general circulation. The portal vein supplies about 75% of blood flow to the liver, while the hepatic artery proper does the remaining 25%. Portal vein conducts blood to capillary beds in the liver. It is not considered a true vein since it does not drain directly to the heart.
Portal vein serves as a primary component of the hepatic portal system, which is one of two portal venous systems in the human body. The length of the portal vein is three to four inches, and it is formed by merging several veins, including superior mesenteric and splenic veins. There are different conditions associated with the portal vein causing considerable illness and death. Portal hypertension is one such example and is a serious complication of liver cirrhosis.
What are the Similarities Between Hepatic Vein and Portal Vein?
- Hepatic vein and portal vein are two different types of veins associated with the liver.
- Both veins play important roles in the human body, which are extremely important for human survival.
- The problems involving these veins cause medical diseases.
What is the Difference Between Hepatic Vein and Portal Vein?
Hepatic vein carries blood from the liver into the inferior vena cava, while portal vein transports blood from the gastrointestinal tract, pancreas, gall bladder, and spleen into the liver. Thus, this is the key difference between hepatic vein and portal vein. Furthermore, hepatic vein carries low-oxygen blood, while portal vein carries partially oxygenated blood. Therefore, this is also a difference between hepatic vein and portal vein.
The below infographic presents the differences between hepatic vein and portal vein in tabular form for side by side comparison.
Summary – Hepatic Vein vs Portal Vein
Hepatic vein and portal vein are two veins connected with the liver. Hepatic vein transports low-oxygen blood from the liver to the inferior vena cava going to the right atrium. On the other hand, hepatic portal vein transports oxygen-rich blood from the gastrointestinal tract and spleen to the liver. So, this summarizes the difference between hepatic vein and portal vein.
Reference:
1. “What Is a Hepatic Vein and What Does It Do?” WebMD.
2. “Hepatic Portal System.” An Overview | ScienceDirect Topics.
Image Courtesy:
1. “2138 Hepatic Portal Vein System” By OpenStax College – Anatomy & Physiology, Connexions Web site, Jun 19, 2013. (CC BY 3.0) via Commons Wikimedia