Portal Hypertension: Causes and Pathophysiology

Definition and Pathophysiology

• Portal hypertension is a condition characterized by elevated blood pressure in the portal vein, which carries blood from the digestive organs to the liver.
• Normal portal vein pressure: 5-10 mmHg
• Portal hypertension: >10 mmHg

Causes

• Cirrhosis (most common cause)
• Portal vein thrombosis
• Budd-Chiari syndrome (hepatic vein thrombosis)
• Splenic vein thrombosis
• Schistosomiasis
• Other rare causes (e.g., sarcoidosis, lymphoma)

Clinical Features

• Gastrointestinal bleeding (esophageal varices, gastric varices, rectal varices)
• Ascites (fluid accumulation in the peritoneal cavity)
• Encephalopathy (hepatic encephalopathy)
• Splenomegaly (enlarged spleen)
• Hypersplenism (decreased blood cells due to spleen sequestration)

Diagnosis

• Endoscopy: to detect esophageal varices
• Imaging: ultrasound, CT, MRI to evaluate liver, spleen, and portal vein
• Measurement of portal vein pressure (invasive procedure)

Management

• Treatment of underlying cause (e.g., cirrhosis)
• Pharmacological therapy:
  • Beta-blockers (e.g., propranolol) to reduce portal pressure
  • Nitrates (e.g., isosorbide mononitrate) to reduce portal pressure
  • Vasoconstrictors (e.g., octreotide) to manage bleeding
• Endoscopic therapy: banding or sclerotherapy for esophageal varices
• Transjugular intrahepatic portosystemic shunt (TIPS) for refractory bleeding or ascites
• Liver transplantation (in selected cases)

Definition and Pathophysiology

• Portal hypertension is characterized by elevated blood pressure in the portal vein, carrying blood from digestive organs to the liver.
• Normal portal vein pressure is 5-10 mmHg, while portal hypertension is above 10 mmHg.

Causes

• Cirrhosis is the most common cause of portal hypertension.
• Other causes include portal vein thrombosis, Budd-Chiari syndrome, splenic vein thrombosis, schistosomiasis, and rare causes like sarcoidosis and lymphoma.

Clinical Features

• Gastrointestinal bleeding occurs due to esophageal varices, gastric varices, and rectal varices.
• Ascites, or fluid accumulation in the peritoneal cavity, is a common feature.
• Hepatic encephalopathy and splenomegaly (enlarged spleen) can also occur.
• Hypersplenism can lead to decreased blood cells due to spleen sequestration.

Diagnosis

• Endoscopy is used to detect esophageal varices.
• Imaging techniques like ultrasound, CT, and MRI evaluate the liver, spleen, and portal vein.
• Measuring portal vein pressure is an invasive procedure.

Management

• Treating the underlying cause, such as cirrhosis, is essential.
• Beta-blockers like propranolol and nitrates like isosorbide mononitrate reduce portal pressure.
• Vasoconstrictors like octreotide manage bleeding.
• Endoscopic therapy involves banding or sclerotherapy for esophageal varices.
• Transjugular intrahepatic portosystemic shunt (TIPS) is used for refractory bleeding or ascites.
• Liver transplantation is an option in selected cases.