Portal hypertension

Portal hypertension

The portal vein and its tributaries
Classification and external resources
Specialty	Gastroenterology
ICD-10	K76.6
ICD-9-CM	572.3
DiseasesDB	10388
eMedicine	radio/570 med/1889
MeSH	D006975

Portal hypertension is hypertension (high blood pressure) in the hepatic portal system, which are the portal vein and its branches, which draining from most of the intestines to the liver. Portal hypertension is defined as a hepatic venous pressure gradient equal to or greater than 6 mmHg.^[1] Cirrhosis (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),^[2]
- Abdominal pain or tenderness ^[3] (when bacteria infect the ascites, as in Spontaneous bacterial peritonitis).
Increased spleen size (Splenomegaly),^[2] which may lead to lower platelet counts (thrombocytopenia)
Swollen veins of the oesophagus (Oesophageal varices), which may bleed and cause vomiting of blood (haematemesis)
Swollen veins on the anterior abdominal wall (sometimes referred to as Caput medusae) ^[2]
Hemorrhoids^[4] (swollen or dilated hemorrhoidal veins)

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 causes is cirrhosis (chronic liver failure). Other causes include:^[2]^[5]^[6]

	Conditions associated with non-cirrhotic portal hypertension
Prehepatic causes	Portal vein thrombosis or splenic vein thrombosis
	Arteriovenous fistula
	Splenomegaly (increased portal blood flow)
Hepatic causes	Any cause of cirrhosis, e.g. alcohol abuse, chronic viral hepatitis, biliary atresia, etc.
	Primary biliary cirrhosis
	Primary sclerosing cholangitis
	Chronic pancreatitis
	Hereditary haemorrhagic telangiectasia
	Schistosomiasis
	Congenital hepatic fibrosis
	Nodular regenerative hyperplasia
	Fibrosis of space of Disse
	Granulomatous or infiltrative liver diseases (Gaucher, mucopolysaccharidosis, sarcoidosis, lymphoproliferative malignancies, amyloid deposition, …)
	Toxicity (from arsenic, copper, vinyl chloride monomers, mineral oil, vitamin A, azathioprine, dacarbazine, methotrexate, amiodarone, …)
	Viral hepatitis
	Fatty liver disease
	Veno-occlusive disease
	Budd-Chiari syndrome
Posthepatic causes	Inferior vena cava obstruction
	(Right-sided) heart failure, e.g. from constrictive pericarditis
	hepatic vein thrombosis

Pathophysiology

Stellate cell

The pathophysiology of portal hypertension is indicated by increasing vascular resistance via different etiologies; additionally, stellate cells and myofibroblasts are activated. Increased endogenous vasodilators in turn promote more blood flow in the portal veins.^[2]^[7]

Nitric oxide is an endogenous vasodilator and it regulates intrahepatic vascular tone (it is produced from L-arginine). According to Maruyama, et al., in laboratory studies nitric oxide inhibition increases portal hypertension and hepatic response to norepinephrine is increased.^[8]

Diagnosis

Portal hypertension due to cirrhosis resulting in revascularization of the umbilical vein

The diagnosis of portal hypertension can be done via HVPG (hepatic venous pressure gradient) measurement has been accepted as the gold standard 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.^[9]

In clinical practice the pressure is not measured directly until the decision to take a liver biopsy for suspected cirrhosis (chronic liver failure), or to place a transjugular intrahepatic portosystemic shunt has been made. Part of the procedure, a hepatic vein wedge pressure is measured with the assumption of no pressure drop across the liver yielding portal vein pressure.

Treatment

The treatment of portal hypertension is divided into:

Portosystemic shunts

Fluoroscopic image of transjugular intrahepatic portosystemic shunt (TIPS)

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.^[10] 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) a graft, either synthetic or the preferred vein harvested from somewhere else 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.^[11]^[12]

It should be noted that 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.^[13]

Prevention of bleeding

Both pharmacological (non-specific β-blockers, nitrate isosorbide mononitrate, vasopressin such as terlipressin) and endoscopic (banding ligation) treatment have similar results. TIPS (transjugular intrahepatic portosystemic shunting) is effective at reducing the rate of rebleeding.^[14]

The management of active variceal bleeding includes administering vasoactive drugs (somatostatin, octreotide), endoscopic banding ligation, balloon tamponade and TIPS.^[14]^[15]

Ascites

This should be gradual to avoid sudden changes in systemic volume status which can precipitate hepatic encephalopathy, renal failure and death. The management includes salt restriction, diuretics (spironolactone), paracentesis, and transjugular intrahepatic portosystemic shunt.^[16]

Hepatic encephalopathy

A treatment plan may involve lactulose, enemas, and use of antibiotics such as rifaximin, neomycin, vancomycin, and the quinolones. 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.^[17]

References

↑ "Portal hypertension | Disease | Overview | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program". rarediseases.info.nih.gov. Retrieved 2016-01-08.
1 2 3 4 5 "Portal Hypertension. Learn about Portal Hypertension | Patient". Patient. Retrieved 2016-01-08.
↑ "Spontaneous Bacterial Peritonitis". www.karger.com. Retrieved 2016-01-08.
↑ Sun, Z; Migaly, J (March 2016). "Review of Hemorrhoid Disease: Presentation and Management.". Clinics in colon and rectal surgery. 29 (1): 22–9. doi:10.1055/s-0035-1568144. PMID 26929748.
↑ Bloom, S.; Kemp, W.; Lubel, J. (2015-01-01). "Portal hypertension: pathophysiology, diagnosis and management". Internal Medicine Journal. 45 (1): 16–26. doi:10.1111/imj.12590. ISSN 1445-5994.
↑ Perkins, [edited by] Vinay Kumar, Abul K. Abbas, Jon C. Aster ; artist, James A. Robbins basic pathology (9th ed.). Philadelphia, PA: Elsevier/Saunders. p. 608. ISBN 978-1-4377-1781-5. 2013
↑ "Portal Hypertension: Practice Essentials, Background, Anatomy".
↑ Maruyama, Hitoshi; Yokosuka, Osamu (2012). "Pathophysiology of Portal Hypertension and Esophageal Varices". International Journal of Hepatology. 2012: 1–7. doi:10.1155/2012/895787. |access-date= requires |url= (help)
↑ Al-Busafi SA, McNabb-Baltar J, Farag A, Hilzenrat N (2012). "Clinical manifestations of portal hypertension". Int J Hepatol. 2012: 203794. doi:10.1155/2012/203794. PMC 3457672. PMID 23024865.
↑ Shah, Omar Javed; Robbani, Irfan (2005-01-01). "A Simplified Technique of Performing Splenorenal Shunt (Omar's Technique)". Texas Heart Institute Journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital. 32 (4): 549–554. ISSN 0730-2347. PMC 1351828. PMID 16429901.
↑ Moore, Wesley S. (2012-11-23). Vascular and Endovascular Surgery: A Comprehensive Review. Elsevier Health Sciences. p. 851. ISBN 1455753866.
↑ Yin, Lanning; Liu, Haipeng; Zhang, Youcheng; Rong, Wen (2013). "The Surgical Treatment for Portal Hypertension: A Systematic Review and Meta-Analysis". ISRN Gastroenterology. 2013: 1–10. doi:10.1155/2013/464053. |access-date= requires |url= (help)
↑ Pomier-Layrargues, Gilles; Bouchard, Louis; Lafortune, Michel; Bissonnette, Julien; Guérette, Dave; Perreault, Pierre (2012). "The Transjugular Intrahepatic Portosystemic Shunt in the Treatment of Portal Hypertension: Current Status". International Journal of Hepatology. 2012: 1–12. doi:10.1155/2012/167868. |access-date= requires |url= (help)
1 2 Bari, Khurram; Garcia-Tsao, Guadalupe (2012-03-21). "Treatment of portal hypertension". World Journal of Gastroenterology : WJG. 18 (11): 1166–1175. doi:10.3748/wjg.v18.i11.1166. ISSN 1007-9327. PMC 3309905. PMID 22468079.
↑ "Portal Hypertension Medication: Somatostatin Analogs, Beta-Blockers, Nonselective, Vasopressin-Related, Vasodilators". emedicine.medscape.com. Retrieved 2016-01-08.
↑ Dib, Nina; Oberti, Frédéric; Calès, Paul (2006-05-09). "Current management of the complications of portal hypertension: variceal bleeding and ascites". Canadian Medical Association Journal. 174 (10): 1433–1443. doi:10.1503/cmaj.051700. ISSN 0820-3946. PMC 1455434. PMID 16682712.
↑ http://www.patient.info/doctor/Hepatic-Encephalopathy.htm

External links

Ascites at Merck Manual of Diagnosis and Therapy Home Edition
Children's Liver Disease Foundation

Diseases of the digestive system (primarily K20–K93, 530–579)

Upper GI tract

Esophagus	Esophagitis Candidal Eosinophilic Herpetiform Rupture Boerhaave syndrome Mallory-Weiss syndrome UES Zenker's diverticulum LES Barrett's esophagus Esophageal motility disorder Nutcracker esophagus Achalasia Diffuse esophageal spasm Gastroesophageal reflux disease (GERD) Laryngopharyngeal reflux (LPR) Esophageal stricture Megaesophagus

Stomach	Gastritis Atrophic Ménétrier's disease Gastroenteritis Peptic (gastric) ulcer Cushing ulcer Dieulafoy's lesion Dyspepsia Pyloric stenosis Achlorhydria Gastroparesis Gastroptosis Portal hypertensive gastropathy Gastric antral vascular ectasia Gastric dumping syndrome Gastric volvulus

Lower GI tract:
Intestinal/
Enteropathy

Small intestine (Duodenum/Jejunum/Ileum)	Enteritis Duodenitis Jejunitis Ileitis Peptic (duodenal) ulcer Curling's ulcer Malabsorption: Coeliac Tropical sprue Blind loop syndrome Small bowel bacterial overgrowth syndrome Whipple's Short bowel syndrome Steatorrhea Milroy disease Bile acid malabsorption

Large intestine (Appendix/Colon)	Appendicitis Colitis Pseudomembranous Ulcerative Ischemic Microscopic Collagenous Lymphocytic Functional colonic disease IBS Intestinal pseudoobstruction / Ogilvie syndrome Megacolon / Toxic megacolon Diverticulitis/Diverticulosis

Large and/or small	Enterocolitis Necrotizing Gastroenterocolitis IBD Crohn's disease Vascular: Abdominal angina Mesenteric ischemia Angiodysplasia Bowel obstruction: Ileus Intussusception Volvulus Fecal impaction Constipation Diarrhea Infectious Intestinal adhesions

Rectum	Proctitis Radiation proctitis Proctalgia fugax Rectal prolapse Anismus

Anal canal	Anal fissure/Anal fistula Anal abscess Anal dysplasia Pruritus ani

GI bleeding/BIS

Accessory

Liver	Hepatitis Viral hepatitis Autoimmune hepatitis Alcoholic hepatitis Cirrhosis PBC Fatty liver NASH Vascular Budd-Chiari syndrome Hepatic veno-occlusive disease Portal hypertension Nutmeg liver Alcoholic liver disease Liver failure Hepatic encephalopathy Acute liver failure Liver abscess Pyogenic Amoebic Hepatorenal syndrome Peliosis hepatis Metabolic disorders Wilson's disease Hemochromatosis

Gallbladder	Cholecystitis Gallstones/Cholecystolithiasis Cholesterolosis Rokitansky-Aschoff sinuses Postcholecystectomy syndrome Porcelain gallbladder

Bile duct/ Other biliary tree	Cholangitis Primary sclerosing cholangitis Secondary sclerosing cholangitis Ascending Cholestasis/Mirizzi's syndrome Biliary fistula Haemobilia Gallstones/Cholelithiasis Common bile duct Choledocholithiasis Biliary dyskinesia Sphincter of Oddi dysfunction

Pancreatic	Pancreatitis Acute Chronic Hereditary Pancreatic abscess Pancreatic pseudocyst Exocrine pancreatic insufficiency Pancreatic fistula

Abdominopelvic

Hernia	Diaphragmatic Congenital Hiatus Inguinal Indirect Direct Umbilical Femoral Obturator Spigelian Lumbar Petit's Grynfeltt-Lesshaft Undefined location Incisional Internal hernia Richter's

Peritoneal	Peritonitis Spontaneous bacterial peritonitis Hemoperitoneum Pneumoperitoneum

Cardiovascular disease (vessels) (I70–I99, 440–456)

Arteries, arterioles
and capillaries

Inflammation

Peripheral artery disease

Arteriosclerosis	Atherosclerosis Foam cell Fatty streak Atheroma Intermittent claudication Critical limb ischemia Monckeberg's arteriosclerosis Arteriolosclerosis Hyaline Hyperplastic Cholesterol LDL Oxycholesterol Trans fat

Stenosis	Carotid artery stenosis Renal artery stenosis

Other	Aortoiliac occlusive disease Degos disease Erythromelalgia Fibromuscular dysplasia Raynaud's phenomenon

Aneurysm / dissection /
pseudoaneurysm

Vascular malformation

Vascular nevus

Veins

Inflammation	Phlebitis

Venous thrombosis / Thrombophlebitis	primarily lower limb Deep vein thrombosis abdomen Hepatic veno-occlusive disease Budd–Chiari syndrome May–Thurner syndrome Portal vein thrombosis Renal vein thrombosis upper limb / torso Mondor's disease Paget–Schroetter disease head Cerebral venous sinus thrombosis Post-thrombotic syndrome

Varicose veins	Gastric varices Portacaval anastomosis Caput medusae Esophageal varices Hemorrhoid Varicocele

Other	Chronic venous insufficiency Chronic cerebrospinal venous insufficiency Superior vena cava syndrome Inferior vena cava syndrome Venous ulcer

Arteries or veins

Blood pressure

Hypertension	Hypertensive heart disease Hypertensive emergency Hypertensive nephropathy Essential hypertension Secondary hypertension Renovascular hypertension Benign hypertension Pulmonary hypertension Systolic hypertension White coat hypertension

Hypotension	Orthostatic hypotension

Authority control	NDL: 00567833

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