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Transjugular intrahepatic portosystemic shunt (TIPS or TIPSS) is an artificial channel within the
liver The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for ...
that establishes communication between the inflow portal vein and the outflow
hepatic vein In human anatomy, the hepatic veins are the veins that drain venous blood from the liver into the inferior vena cava (as opposed to the hepatic portal vein which conveys blood from the gastrointestinal organs to the liver). There are usually thre ...
. It is used to treat portal hypertension (which is often due to
liver cirrhosis Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, and end-stage liver disease, is the impaired liver function caused by the formation of scar tissue known as fibrosis due to damage caused by liver disease. Damage causes tissue repai ...
) which frequently leads to intestinal bleeding, life-threatening esophageal bleeding (
esophageal varices Esophageal varices are extremely dilated sub-mucosal veins in the lower third of the esophagus. They are most often a consequence of portal hypertension, commonly due to cirrhosis. People with esophageal varices have a strong tendency to develop ...
) and the buildup of fluid within the abdomen (
ascites Ascites is the abnormal build-up of fluid in the abdomen. Technically, it is more than 25 ml of fluid in the peritoneal cavity, although volumes greater than one liter may occur. Symptoms may include increased abdominal size, increased weight, ab ...
). An
interventional radiologist Interventional radiology (IR) is a medical specialty that performs various minimally-invasive procedures using medical imaging guidance, such as x-ray fluoroscopy, computed tomography, magnetic resonance imaging, or ultrasound. IR performs bo ...
creates the shunt using an image-guided
endovascular Interventional radiology (IR) is a medical specialty that performs various minimally-invasive procedures using medical imaging guidance, such as x-ray fluoroscopy, computed tomography, magnetic resonance imaging, or ultrasound. IR performs b ...
(via the
blood vessel The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...
s) approach, with the
jugular vein The jugular veins are veins that take deoxygenated blood from the head back to the heart via the superior vena cava. The internal jugular vein descends next to the internal carotid artery and continues posteriorly to the sternocleidomastoid mu ...
as the usual entry site. The procedure was first described by Josef Rösch in 1969 at
Oregon Health and Science University Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...
. It was first used in a human patient by Dr. Ronald Colapinto, of the
University of Toronto The University of Toronto (UToronto or U of T) is a public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution ...
, in 1982, but did not become reproducibly successful until the development of endovascular stents in 1985. In 1988 the first successful TIPS was realized by M. Rössle, G.M. Richter, G. Nöldge and J. Palmaz at the
University of Freiburg The University of Freiburg (colloquially german: Uni Freiburg), officially the Albert Ludwig University of Freiburg (german: Albert-Ludwigs-Universität Freiburg), is a public university, public research university located in Freiburg im Breisg ...
. The procedure has since become widely accepted as the preferred method for treating portal hypertension that is refractory to medical therapy, replacing the surgical portocaval shunt in that role.


Medical uses

TIPS is a life-saving procedure in bleeding from esophageal or gastric varices. A randomized study showed that the survival is better if the procedure is done within 72 hours after
bleeding Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
. TIPS has shown some promise for people with
hepatorenal syndrome Hepatorenal syndrome (often abbreviated HRS) is a life-threatening medical condition that consists of rapid deterioration in kidney function in individuals with cirrhosis or fulminant liver failure. HRS is usually fatal unless a liver transpla ...
. It may also help with
ascites Ascites is the abnormal build-up of fluid in the abdomen. Technically, it is more than 25 ml of fluid in the peritoneal cavity, although volumes greater than one liter may occur. Symptoms may include increased abdominal size, increased weight, ab ...
.


Complications

Severe procedural complications during a TIPS procedure, including catastrophic bleeding or direct liver injury, are relatively uncommon. In the hands of an experienced physician, operative mortality is less than 1%. On the other hand, up to 25% of patients who undergo TIPS will experience transient post-operative
hepatic encephalopathy Hepatic encephalopathy (HE) is an altered level of consciousness as a result of liver failure. Its onset may be gradual or sudden. Other symptoms may include movement problems, changes in mood, or changes in personality. In the advanced stages ...
caused by increased porto-systemic passage of nitrogen from the gut. A less common, but more serious complication, is hepatic ischemia causing acute liver failure. While healthy livers are predominantly oxygenated by portal blood supply, long-standing portal hypertension results in compensatory hypertrophy of and increased reliance on the hepatic artery for oxygenation. Thus, in people with advanced liver disease the shunting of portal blood away from hepatocytes is usually well tolerated. However, in some cases suddenly shunting portal blood flow away from the liver may result in acute liver failure secondary to hepatic ischemia. Acute hepatic dysfunction after TIPS may require emergent closure of the shunt. A rare but serious complication is persistent TIPS infection, also known as endotipsitis. Lastly, the TIPS may become blocked by a blood clot or in-growth of endothelial cells and no longer function. This has been significantly reduced with the use of
polytetrafluoroethylene Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. It is one of the best-known and widely applied PFAS. The commonly known brand name of PTFE-based composition is Teflon by Chemour ...
(PTFE)–covered stents.


Mechanism of action

Portal hypertension, an important consequence of liver disease, results in the development of significant
collateral circulation Collateral circulation is the alternate circulation around a blocked artery or vein via another path, such as nearby minor vessels. It may occur via preexisting vascular redundancy (analogous to engineered redundancy), as in the circle of Wil ...
between the portal system and systemic venous drainage (porto-caval circulation). Portal venous congestion causes venous blood leaving the stomach and intestines to be diverted along auxiliary routes of lesser resistance in order to drain to systemic circulation. With time, the small vessels that comprise a collateral path for porto-caval circulation become engorged and dilated. These vessels are fragile and often hemorrhage into the GI tract. (''See esophageal,
gastric The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach i ...
,
rectal varices Anorectal varices are the dilation of collateral submucosal vessels due to backflow in the veins of the rectum. Typically this occurs due to portal hypertension which shunts venous blood from the portal system through the portosystemic anasto ...
''). A TIPS procedure decreases the effective
vascular resistance Vascular resistance is the resistance that must be overcome to push blood through the circulatory system and create flow. The resistance offered by the systemic circulation is known as the systemic vascular resistance (SVR) or may sometimes be cal ...
of the liver through the creation of an alternative pathway for portal venous circulation. By creating a shunt from the portal vein to the hepatic vein, this intervention allows portal blood an alternative avenue for draining into systemic circulation. In bypassing the flow-resistant liver, the net result is a reduced
pressure drop Pressure drop is defined as the difference in total pressure between two points of a fluid carrying network. A pressure drop occurs when frictional forces, caused by the resistance to flow, act on a fluid as it flows through the tube. The main de ...
across the liver and a decreased portal venous pressure. Decreased portal venous pressure in turn lessens congestive pressures along veins in the intestine so that future bleeding is less likely to occur. The reduced pressure also makes less fluid develop, although this benefit may take weeks or months to occur.


Implantation

Transjugular intrahepatic portosystemic shunts are typically placed by an interventional radiologist under
fluoroscopic Fluoroscopy () is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a physician to see the internal anatomy, structure and ...
guidance. Access to the liver is gained, as the name 'transjugular' suggests, via the
internal jugular vein The internal jugular vein is a paired jugular vein that collects blood from the brain and the superficial parts of the face and neck. This vein runs in the carotid sheath with the common carotid artery and vagus nerve. It begins in the posteri ...
in the
neck The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In ...
. Once access to the jugular vein is confirmed, a guidewire and introducer sheath are typically placed to facilitate the shunt's placement. This enables the interventional radiologist to gain access to the patient's
hepatic vein In human anatomy, the hepatic veins are the veins that drain venous blood from the liver into the inferior vena cava (as opposed to the hepatic portal vein which conveys blood from the gastrointestinal organs to the liver). There are usually thre ...
by traveling from the superior vena cava into the inferior vena cava and finally the hepatic vein. Once the catheter is in the hepatic vein, a wedge pressure is obtained to calculate the pressure gradient in the liver. Following this, carbon dioxide is injected to locate the portal vein. Then, a special needle known as a Colapinto is advanced through the liver parenchyma to connect the hepatic vein to the large portal vein, near the center of the liver. The channel for the shunt is next created by inflating an angioplasty balloon within the liver along the tract created by the needle. The shunt is completed by placing a special mesh tube known as a
stent In medicine, a stent is a metal or plastic tube inserted into the lumen of an anatomic vessel or duct to keep the passageway open, and stenting is the placement of a stent. A wide variety of stents are used for different purposes, from expandab ...
or endograft to maintain the tract between the higher-pressure portal vein and the lower-pressure hepatic vein. After the procedure, fluoroscopic images are made to show placement. Pressure in the portal vein and inferior vena cava are often measured.


See also

*
Balloon-occluded retrograde transvenous obliteration Balloon-occluded retrograde transvenous obliteration (BRTO) is an endovascular procedure used for the treatment of gastric varices. When performing the procedure, an interventional radiologist accesses blood vessels using a catheter, inflates a ...
*
Distal splenorenal shunt procedure In medicine, a distal splenorenal shunt procedure (DSRS), also splenorenal shunt procedure and Warren shunt, is a surgical procedure in which the distal splenic vein (a part of the portal venous system) is attached to the left renal vein (a part o ...
*
Gastric antral vascular ectasia Gastric antral vascular ectasia (GAVE) is an uncommon cause of chronic gastrointestinal bleeding or iron deficiency anemia. The condition is associated with dilated small blood vessels in the pyloric antrum, which is a distal part of the stomach. T ...
*
Portal venous system In the circulatory system of animals, a portal venous system occurs when a capillary bed pools into another capillary bed through veins, without first going through the heart. Both capillary beds and the blood vessels that connect them are con ...


References


External links


RadiologyInfo: Transjugular Intrahepatic Portosystemic Shunt (TIPS)

Transjugular Intrahepatic Portosystemic Shunt
- eMedicine.com. {{Vascular surgery procedures Accessory digestive gland surgery Hepatology Implants (medicine) Vascular surgery Interventional radiology