Portal hypertension is abnormally increased portal venous pressure – blood pressure in the portal vein and its branches, that drain from most of the intestine to the

liver The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it i ...

. Portal hypertension is defined as a hepatic venous pressure gradient greater than 5 mmHg.

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 rep ...

(a form of chronic liver failure) is the most common cause of portal hypertension; other, less frequent causes are therefore grouped as non-cirrhotic portal hypertension. When it becomes severe enough to cause symptoms or complications, treatment may be given to decrease portal hypertension itself or to manage its complications.

Signs and symptoms

Signs and symptoms of portal hypertension include: * Ascites (free fluid in the peritoneal cavity), ** Abdominal pain or tenderness (when bacteria infect the ascites, as in

spontaneous bacterial peritonitis Spontaneous bacterial peritonitis (SBP) is the development of a bacterial infection in the peritoneum, despite the absence of an obvious source for the infection. It is specifically an infection of the ascitic fluid – an increased volume of pe ...

). * Increased spleen size ( splenomegaly), which may lead to lower platelet counts ( thrombocytopenia) * Anorectal varices * Swollen veins on the anterior abdominal wall (sometimes referred to as caput medusae) In addition, a widened (dilated) portal vein as seen on a CT scan or MRI may raise the suspicion about portal hypertension. A cutoff value of 13 mm is widely used in this regard, but the diameter is often larger than this is in normal individuals as well.

Causes

The causes for portal hypertension are classified as originating in the portal venous system before it reaches the liver (''prehepatic'' causes), within the liver (''intrahepatic'') or between the liver and the heart (post-hepatic). The most common cause is cirrhosis (chronic liver failure). Other causes include:2013 Prehepatic causes *

Portal vein thrombosis Portal vein thrombosis (PVT) is a vascular disease of the liver that occurs when a blood clot occurs in the hepatic portal vein, which can lead to increased pressure in the portal vein system and reduced blood supply to the liver. The mortalit ...

* Splenic vein

thrombosis Thrombosis (from Ancient Greek "clotting") is the formation of a blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel (a vein or an artery) is injured, the body uses platelets (th ...

Arteriovenous fistula An arteriovenous fistula is an abnormal connection or passageway between an artery and a vein. It may be congenital, surgically created for hemodialysis treatments, or acquired due to pathologic process, such as trauma or erosion of an arterial ...

(increased portal blood flow) * Splenomegaly and/or hypersplenism (increased portal blood flow) Hepatic causes *

of any cause. ** alcohol use disorder **

chronic viral hepatitis Hepatitis is inflammation of the liver tissue. Some people or animals with hepatitis have no symptoms, whereas others develop yellow discoloration of the skin and whites of the eyes (jaundice), poor appetite, vomiting, tiredness, abdominal pa ...

biliary atresia Biliary atresia, also known as extrahepatic ductopenia and progressive obliterative cholangiopathy, is a childhood disease of the liver in which one or more bile ducts are abnormally narrow, blocked, or absent. It can be congenital or acquired. I ...

** Primary biliary cirrhosis * Primary sclerosing cholangitis * Chronic pancreatitis * Hereditary haemorrhagic telangiectasia * Schistosomiasis *

Congenital hepatic fibrosis Congenital hepatic fibrosis is an inherited fibrocystic liver disease associated with proliferation of interlobular bile ducts within the portal areas and fibrosis that do not alter hepatic lobular architecture. The fibrosis would affect resist ...

* Nodular regenerative hyperplasia * Fibrosis of space of Disse * Granulomatous or infiltrative liver diseases ( Gaucher disease, mucopolysaccharidosis,

sarcoidosis Sarcoidosis (also known as ''Besnier-Boeck-Schaumann disease'') is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomata. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly af ...

, lymphoproliferative malignancies,

amyloidosis Amyloidosis is a group of diseases in which abnormal proteins, known as amyloid fibrils, build up in tissue. There are several non-specific and vague signs and symptoms associated with amyloidosis. These include fatigue, peripheral edema, weig ...

, etc.) * Toxicity (from arsenic, copper, vinyl chloride monomers, mineral oil, vitamin A, azathioprine, dacarbazine, methotrexate, amiodarone, etc.) * Viral hepatitis * Fatty liver disease * Veno-occlusive disease Posthepatic causes * Inferior vena cava obstruction *

Right-sided heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, an ...

, e.g. from

constrictive pericarditis Constrictive pericarditis is a medical condition characterized by a thickened, fibrotic pericardium, limiting the heart's ability to function normally. In many cases, the condition continues to be difficult to diagnose and therefore benefits from ...

Budd–Chiari syndrome Budd–Chiari syndrome is a very rare condition, affecting one in a million adults. The condition is caused by occlusion of the hepatic veins that drain the liver. It presents with the classical triad of abdominal pain, ascites, and liver enlar ...

also known as hepatic vein thrombosis

Pathophysiology

The pathophysiology of portal hypertension is indicated by increased vascular resistance via different causes; additionally, hepatic stellate cells and myofibroblasts are activated. Increased endogenous vasodilators in turn promote more blood flow in the portal

veins Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated ...

. Nitric oxide is an endogenous vasodilator and it regulates intrahepatic vascular tone (it is produced from

L-arginine Arginine is the amino acid with the formula (H2N)(HN)CN(H)(CH2)3CH(NH2)CO2H. The molecule features a guanidino group appended to a standard amino acid framework. At physiological pH, the carboxylic acid is deprotonated (−CO2−) and both the am ...

). Nitric oxide inhibition has been shown in some studies to increase portal hypertension and hepatic response to

norepinephrine Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad ...

Diagnosis

PortalHypertension(revascuofumbilicalvein)Mark

Ultrasonography (US) is the first-line imaging technique for the diagnosis and follow-up of portal hypertension because it is non-invasive, low-cost and can be performed on-site. A dilated portal vein (diameter of greater than 13 or 15 mm) is a sign of portal hypertension, with a sensitivity estimated at 12.5% or 40%. On

Doppler ultrasonography Doppler ultrasonography is medical ultrasonography that employs the Doppler effect to perform imaging of the movement of tissues and body fluids (usually blood), and their relative velocity to the probe. By calculating the frequency shift of a ...

, a slow velocity of <16 cm/s in addition to dilatation in the main portal vein are diagnostic of portal hypertension. Other signs of portal hypertension on ultrasound include a portal flow mean velocity of less than 12 cm/s, porto–systemic collateral veins (patent

paraumbilical vein In the course of the round ligament of liver, small veins (paraumbilical) are found which establish an anastomosis between the veins of the anterior abdominal wall and the hepatic portal, hypogastric, and iliac veins. The best marked of these sm ...

, spleno–renal collaterals and dilated left and short gastric veins), splenomegaly and signs of cirrhosis (including nodularity of the liver surface). The hepatic venous pressure gradient (HVPG) measurement has been accepted as the

gold standard A gold standard is a monetary system in which the standard economic unit of account is based on a fixed quantity of gold. The gold standard was the basis for the international monetary system from the 1870s to the early 1920s, and from th ...

for assessing the severity of portal hypertension. Portal hypertension is defined as HVPG greater than or equal to 5 mm Hg and is considered to be clinically significant when HVPG exceeds 10 to 12 mm Hg.

Treatment

The treatment of portal hypertension is divided into:

Portosystemic shunts

Fluoroscopic image of transjugular intrahepatic portosystemic shunt (TIPS) in progress

Selective shunts select non-intestinal flow to be shunted to the systemic venous drainage while leaving the intestinal venous drainage to continue to pass through the liver. The most well known of this type is the splenorenal. This connects the splenic vein to the left renal vein thus reducing portal system pressure while minimizing any encephalopathy. In an H-shunt, which could be mesocaval (from the superior mesenteric vein to the inferior vena cava) or could be, portocaval (from the portal vein to the inferior

vena cava In anatomy, the venae cavae (; singular: vena cava ; ) are two large veins (great vessels) that return deoxygenated blood from the body into the heart. In humans they are the superior vena cava and the inferior vena cava, and both empty into th ...

) a graft, either synthetic or the preferred vein harvested from elsewhere on the patient's body, is connected between the superior mesenteric vein and the inferior vena cava. The size of this shunt will determine how selective it is. With the advent of transjugular intrahepatic portosystemic shunting (TIPS), portosystemic shunts are less performed. TIPS has the advantage of being easier to perform and doesn't disrupt the liver's vascularity.

Prevention of bleeding

Both pharmacological (non-specific β-blockers, nitrate isosorbide mononitrate, vasopressin such as

terlipressin Terlipressin, sold under the brand name Terlivaz among others, is an analogue of vasopressin used as a vasoactive drug in the management of low blood pressure. It has been found to be effective when norepinephrine does not help. Terlipressin i ...

) and endoscopic (banding ligation) treatment have similar results. TIPS ( transjugular intrahepatic portosystemic shunting) is effective at reducing the rate of rebleeding. The management of active variceal bleeding includes administering vasoactive drugs (somatostatin, octreotide), endoscopic banding ligation, balloon tamponade and TIPS.

Ascites

The management of ascites needs to be gradual to avoid sudden changes in systemic volume status which can precipitate

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 stage ...

kidney failure Kidney failure, also known as end-stage kidney disease, is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as eit ...

and death. The management includes salt restriction, diuretics (

spironolactone Spironolactone, sold under the brand name Aldactone among others, is a medication that is primarily used to treat fluid build-up due to heart failure, liver scarring, or kidney disease. It is also used in the treatment of high blood press ...

paracentesis Paracentesis (from Greek κεντάω, "to pierce") is a form of body fluid sampling procedure, generally referring to peritoneocentesis (also called laparocentesis or abdominal paracentesis) in which the peritoneal cavity is punctured by a need ...

, and transjugular intrahepatic portosystemic shunt (TIPS).

Hepatic encephalopathy

A treatment plan may involve lactulose, enemas, and use of antibiotics such as rifaximin, neomycin,

vancomycin Vancomycin is a glycopeptide antibiotic medication used to treat a number of bacterial infections. It is recommended intravenously as a treatment for complicated skin infections, bloodstream infections, endocarditis, bone and joint infection ...

, and the

quinolones Quinolone may refer to: * 2-Quinolone * 4-Quinolone 4-Quinolone is an organic compound derived from quinoline. It and 2-quinolone are the two most important parent (meaning simplified) quinolones. 4-Quinolone exists in equilibrium with a mino ...

. Restriction of dietary protein was recommended but this is now refuted by a clinical trial which shows no benefit. Instead, the maintenance of adequate nutrition is now advocated.

References

External links

{{Authority control Accessory digestive gland disorders Hepatology Hypertension