Portal vein thrombosis

Budd-Chiari syndrome is obstruction of hepatic venous outflow, usually hepatic vein thrombosis, causing hepatomegaly, ascites, and right-upper-quadrant pain. Diagnosis is by Doppler ultrasound; first-line treatment is anticoagulation, escalating to angioplasty, stenting, or TIPS for progressive disease.

Cirrhosis is end-stage hepatic fibrosis with regenerative nodules, staged as compensated or decompensated by the onset of ascites, variceal hemorrhage, encephalopathy, or jaundice. Severity is graded by Child-Pugh class and MELD, and management centers on treating the underlying cause, surveillance for varices and hepatocellular carcinoma, and timely transplant referral once decompensation appears.

Gastroesophageal varices are dilated portosystemic collateral veins that form as portal pressure rises in cirrhosis, and their rupture causes acute variceal hemorrhage, a GI emergency treated with vasoactive therapy, prophylactic antibiotics, and urgent endoscopic band ligation. Screening endoscopy in cirrhotics guides primary prophylaxis with a nonselective beta-blocker or ligation, and survivors of a bleed require combined beta-blocker and serial ligation for secondary prophylaxis.

Thrombophilias are inherited or acquired hypercoagulable states that predispose to venous, and in some acquired conditions arterial, thrombosis. Testing is selective and deferred until the patient is off anticoagulation and remote from acute clot, because acute thrombosis, heparin, warfarin, and estrogen all distort results, and most results do not change acute management except in antiphospholipid syndrome.

Antiphospholipid syndrome is an acquired autoimmune thrombophilia in which antiphospholipid antibodies cause recurrent venous and arterial thrombosis and pregnancy morbidity, paradoxically prolonging the aPTT in vitro while promoting clotting in vivo. Diagnosis requires a qualifying clinical event plus a laboratory antibody confirmed positive on two occasions at least 12 weeks apart, and thrombotic disease is treated with indefinite warfarin rather than a DOAC.

Hepatocellular carcinoma is a primary liver cancer that arises almost exclusively in cirrhosis and can be diagnosed non-invasively when multiphase CT or MRI shows arterial-phase hyperenhancement with portal-venous washout in a lesion at least 1 cm. Treatment is stratified by tumor burden, liver function, and vascular or extrahepatic spread, ranging from resection or ablation through transplantation and transarterial chemoembolization to systemic atezolizumab-bevacizumab for advanced disease.

Acute mesenteric ischemia is an abrupt drop in small-bowel blood flow, most often superior mesenteric artery embolism, presenting as severe abdominal pain out of proportion to an unimpressive early examination. CT angiography confirms the diagnosis, and survival depends on immediate resuscitation, antibiotics, and anticoagulation followed by urgent revascularization or resection before infarction and peritonitis develop.

Anticoagulants are drugs that block steps in the coagulation cascade to prevent or treat venous thromboembolism, cardioembolic stroke, and valve thrombosis. Direct oral anticoagulants are first-line for most nonvalvular indications, while warfarin, titrated to an INR of 2 to 3, remains required for mechanical valves and high-risk antiphospholipid syndrome; parenteral heparins bridge and cover renal failure or urgent reversal needs.