Summary
Portal hypertension is the pathological elevation of portal venous pressure resulting from obstructions in portal blood flow, which can be prehepatic (e.g., portal vein thrombosis), hepatic (e.g., liver cirrhosis), or posthepatic (e.g., right-sided heart failure). The subsequent backflow of blood may lead to portosystemic anastomoses, splenomegaly, and/or ascites. A diagnosis of portal hypertension can be made based on clinical signs and knowledge of an underlying cause. In suspected cases, medical imaging and laboratory tests are used to support the diagnosis. Management involves treating the underlying condition and reducing portal pressure with nonselective beta blockers (NSBBs) and portosystemic shunts. Acute hemorrhage of esophageal varices is a potentially life-threatening complication of portal hypertension and is caused by increased blood flow via portosystemic anastomoses.
Etiology
Causes of portal hypertension are described based on the anatomical location of the lesion.
Prehepatic [1]
- Portal vein thrombosis
- Splenic vein thrombosis
- Mesenteric vein thrombosis [2]
- Congenital abnormalities of the portal vein system (e.g., portal vein agenesis)
- Compression of portal or splenic veins [3]
- Arteriovenous fistula
Hepatic [1][4]
Hepatic etiologies of portal hypertension are described anatomically in relation to the hepatic sinusoids.
-
Presinusoidal
- Hepatosplenic schistosomiasis (most common cause of noncirrhotic portal hypertension worldwide) [5]
- Granulomatous diseases (e.g., sarcoidosis, tuberculosis) [3]
- Malignancy (e.g., lymphoma) causing portal vein occlusion
- Biliary diseases (e.g., primary biliary cholangitis, primary sclerosing cholangitis)
- Developmental or genetic abnormalities (e.g., polycystic kidney disease, arteriovenous fistula)
-
Sinusoidal
- Cirrhosis (most common cause of portal hypertension in the US)
- Massive hepatic metastases
- Steatohepatitis
- Congenital hepatic fibrosis
- Amyloidosis
- Drug-induced liver injury (e.g., methotrexate-induced) or toxin-related liver injury (e.g., copper)
- Alcohol-associated liver disease
- Infiltrative diseases (e.g., Gaucher disease)
- Inflammatory and infectious conditions (e.g., viral hepatitis, chronic Q fever)
- Portosinusoidal vascular disorder
-
Postsinusoidal
- Sinusoidal obstruction syndrome
- Vascular malignancy (e.g., angiosarcoma)
- Granulomatous changes (due to, e.g., sarcoidosis or Mycobacterium avium)
- Sclerosis of the hepatic vein (due to, e.g., alcohol or hypervitaminosis A)
Posthepatic [1][3]
- Budd-Chiari syndrome
- Right-sided heart failure [6]
- Constrictive pericarditis
- Obstruction of IVC (e.g., IVC thrombosis)
Pathophysiology
Prehepatic [1][7]
Obstruction of portal vein or splenic vein → ↑ hydrostatic pressure in the tributaries of the obstructed vein
Hepatic [1][7]
- Presinusoidal: obstruction of outflow in portal vein at the porta hepatis or in the portal venules within liver → ↑ hydrostatic pressure in the portal vein and its tributaries
- Sinusoidal: ↑ resistance to blood flow in the hepatic sinusoids (e.g., due to hepatic fibrosis and ↓ intrahepatic nitric oxide production in cirrhosis) → ↑ hydrostatic pressure in the hepatic sinusoids → ↑ hydrostatic pressure in the portal vein and its tributaries
- Postsinusoidal: obstruction of outflow in the central vein and/or hepatic venules → ↑ hydrostatic pressure in the hepatic sinusoids → ↑ hydrostatic pressure in the portal vein and its tributaries
Posthepatic [1][7]
Hepatic vein congestion or obstruction of hepatic vein outflow → ↑ hydrostatic pressure in the hepatic sinusoids → ↑ hydrostatic pressure in the portal vein and its tributaries
Clinical features
The etiology determines whether portal hypertension manifests as acute or chronic.
- Signs and symptoms of underlying disease, e.g.:
-
Signs and symptoms of complications: features of increased blood flow via portosystemic anastomoses
-
Gastrointestinal bleeding [9]
- Hematemesis and/or melena (e.g., due to esophageal varices or gastric varices)
- Hematochezia (e.g., due to hemorrhoidal or anorectal varices)
- Caput medusae
- Signs of hypersplenism due to congestive splenomegaly (e.g., thrombocytopenia)
- Abdominal distention due to ascites
- Hepatic encephalopathy
-
Gastrointestinal bleeding [9]
Patients usually present with signs of their underlying disease and/or symptoms related to the complications of portal hypertension.
Diagnosis
General principles [8][9]
-
CSPH is confirmed in patients with either: [8]
- HVPG measurement ≥ 10 mm Hg
- Surrogate markers of CSPH:
- Complications of portal hypertension: e.g., esophageal varices on EGD, portosystemic collaterals on abdominal imaging
- Abnormal noninvasive tests: transient elastography with PLT count [10]
- Once confirmed, identify the underlying causes of portal hypertension.
- Obtain a diagnostic workup for the most likely cause (e.g., diagnostics for cirrhosis).
- Consult hepatology if the diagnosis remains unclear.
The combination of elevated liver stiffness and thrombocytopenia provides the most reliable estimation of CSPH using noninvasive tests. [8]
Laboratory studies [6][8]
Findings are nonspecific but may further support the diagnosis and help to identify the underlying cause.
-
CBC
- Thrombocytopenia (most common laboratory finding in portal hypertension)
- Anemia related to an underlying condition
- Liver chemistries: transaminitis and/or hyperbilirubinemia suggest liver disease.
- Coagulation panel: coagulopathy is a sign of advanced liver disease
- Ascitic fluid analysis: high SAAG ≥ 1.1 g/dL [6]
Imaging studies [8][11]
Transient elastography [8][10]
- Indications: Obtain for all patients with nonconfirmed disease.
- Findings: Correlate with PLT levels to increase diagnostic yield.
Transient elastography is the recommended noninvasive test for diagnostic confirmation in patients with suspected portal hypertension. [8]
Abdominal imaging [8]
Findings may help establish the diagnosis and identify the underlying cause.
-
Modalities
-
MR elastography
- For diagnostic uncertainty after transient elastography [10]
- Liver stiffness ≥ 5.1 kPa on MR elastography suggests CSPH. [10]
- Doppler ultrasound abdomen: Obtain to assess portal circulation.
- CT or MRI abdomen are usually reserved for:
- Concerns for extrahepatic obstruction
- Preprocedural planning
-
MR elastography
-
Specific findings of CSPH: sufficient to establish a diagnosis of portal hypertension [8][12]
- Portosystemic collateral circulation
- Blood flow reversal in the portal system
-
Nonspecific findings
- Portal and/or splenic vein dilation > 10 mm
- Decreased portal vein velocity on Doppler ultrasound
- Splenomegaly, ascites, and/or varices
- Findings that suggest the underlying cause, e.g.:
- Cirrhosis (e.g., nodular liver)
- Liver masses
- Portal vein thrombosis
Hepatic venous pressure gradient (HVPG) measurement [8][9][13]
- Indication: reserved for diagnostic confirmation in cases of uncertainty (gold standard test) [8]
- Method: Free and wedge occlusion pressures of the hepatic vein are measured via catheterization, using ultrasound or fluoroscopy. [9]
-
Interpretation of HVPG levels [8]
- > 5 mm Hg: mild portal hypertension
- ≥ 10 mm Hg: clinically significant portal hypertension (CSPH) [6]
- > 12 mm Hg: associated with complications (e.g., variceal bleeding) [6]
Esophagogastroduodenoscopy (EGD) [8][9]
-
Indications (all of the following)
- Diagnosis of cirrhosis or compensated advanced chronic liver disease
- Non-invasive methods to diagnose CSPH (e.g., transient elastography) are unavailable
- Interpretation: The presence of esophageal varices of any size confirms the diagnosis of CSPH. [8]
Complications
- Life-threatening esophageal variceal bleeding
- Portal hypertensive gastropathy
- Ascites
- Spontaneous bacterial peritonitis
- Hepatorenal syndrome
- Impaired liver function (see “Cirrhosis”)
- Hepatic encephalopathy
- Pulmonary complications of portal hypertension (e.g., hepatopulmonary syndrome, portopulmonary hypertension)
- Cirrhotic cardiomyopathy
- Gastric antral vascular ectasia
We list the most important complications. The selection is not exhaustive.
Portal hypertensive gastropathy
- Definition: gastric venous and capillary ectasia resulting from CSPH [8]
-
Epidemiology
- Prevalence among patients with compensated cirrhosis: approx. 50–80% [8]
- More common in patients with medium or large gastroesophageal varices than in those with no or small gastroesophageal varices
-
Clinical features
- Often asymptomatic
- Symptoms of iron-deficiency anemia from chronic blood loss
- Features of overt GI bleeding (rare) [8]
-
Diagnostics
-
EGD (first-line) [8]
- Proximal lesions [14]
- Mosaic pattern (“snakeskin” mucosa)
- Intramucosal hemorrhage (red or black-brown markings)
- Portal hypertension (PH) related polyps may be visible. [8]
- Other modalities: CT, MRI, capsule endoscopy [14]
-
EGD (first-line) [8]
-
Management [8]
- Acute GI bleeding from severe PHG
- Vasoactive therapy (e.g., octreotide) at doses used for variceal bleeding for 2–5 days
- See “Management of esophageal variceal hemorrhage.”
- Chronic management
- NSBBs to prevent decompensation or rebleeding
- Management of chronic blood loss [14]
- Iron supplementation
- Blood transfusions
- TIPS for patients who are transfusion-dependent despite NSBB therapy
- Argon plasma coagulation
- Acute GI bleeding from severe PHG
Rule out H. pylori infection (a common differential diagnosis) before initiating prophylactic therapy with NSBBs. [8]
Gastric antral vascular ectasia (GAVE)
- Definition: dilation of small mucosal and submucosal blood vessels in the gastric antrum
-
Associated conditions [14]
- Portal hypertension, cirrhosis
- Chronic kidney disease
- Connective tissue disorders (e.g., systemic sclerosis)
- Cardiovascular disease
- Bone marrow transplantation
-
Clinical features [15]
- Often asymptomatic
- Symptoms of iron-deficiency anemia from chronic blood loss
- Features of overt GI bleeding (rare)
-
Diagnostics: EGD [14]
- Distal linear erythematous streaks
- Classically described as “watermelon stomach”
- Biopsy in selected cases for diagnostic confirmation (e.g., when the diagnosis is uncertain) [14]
-
Management
- Endoscopic therapy, e.g., argon plasma coagulation, radiofrequency ablation, band ligation [15][16]
- Management of chronic blood loss, e.g., iron supplementation, transfusions
- Initial management of overt GI bleeding
While GAVE is associated with portal hypertension, it is not thought to be caused by portal hypertension, and medication to reduce CSPH is ineffective in the management of GAVE. [14]
