Overview
Clinical Meaning
Transjugular intrahepatic portosystemic shunt (TIPS) is an interventional radiologic procedure that creates an artificial communication between the hepatic vein and portal vein...
Transjugular intrahepatic portosystemic shunt (TIPS) is an interventional radiologic procedure that creates an artificial communication between the hepatic vein and portal vein through the hepatic parenchyma, using an expandable metal stent. This shunt decompresses the portal venous system by diverting portal blood flow directly into the systemic venous circulation, reducing the portal-systemic pressure gradient. Portal hypertension develops when hepatic sinusoidal resistance exceeds a threshold portal pressure gradient of >5 mmHg (clinically significant at >10 mmHg); cirrhosis is the most common cause, producing increased intrahepatic resistance from fibrotic distortion of sinusoidal architecture and active hepatic stellate cell contraction. The portal pressure gradient normally is 1-5 mmHg; in portal hypertension it exceeds 10 mmHg, and varices develop at >10-12 mmHg with bleeding risk increasing at >20 mmHg. TIPS reduces the portal pressure gradient to <12 mmHg, below the threshold for variceal bleeding and refractory ascites. The primary consequence of TIPS is hepatic encephalopathy (HE), occurring in 25-45% of patients, because ammonia-laden portal blood bypasses hepatic metabolism and enters the systemic circulation directly. Additionally, the sudden increase in cardiac preload from redirected portal...