Hepatic and portal vein thrombosis in cirrhosis: Possible role in development of parenchymal extinction and portal hypertension

Abstract

Obliterative lesions in portal veins (PVs) and hepatic veins (HVs) of all sizes are known to occur in cirrhotic livers. PV lesions have generally been attributed to thrombosis, but the pathogenesis of the HV (veno-occlusive) lesions is unknown. We have studied 61 cirrhotic livers removed at transplantation to clarify the prevalence, distribution, and pathogenesis of venous lesions, as well as the association of these lesions with other morphological features and clinical morbidity. Intimal fibrosis that is highly suggestive of healed HV or PV thrombosis was found in at least 70% and 36% of livers, respectively. The distribution of HV lesions was patchy and largely confined to veins between 0.1 and 3 mm in diameter, suggesting multifocal origin in small veins. PV lesions were more uniform throughout the liver, suggesting origin in large veins with propagation to the small veins. HV lesions were associated with regions of confluent fibrosis (focal parenchymal extinction), and PV lesions were associated with regional variation in the size of cirrhotic nodules and a history of bleeding varices. These observations suggest that thrombosis of medium and large PVs and HVs is a frequent occurrence in cirrhosis, and that these events are important in causing progression of cirrhosis.

Arterial and Portal Circulation and Parenchymal Changes in Budd–Chiari Syndrome: A Study in 17 Explanted Livers

“…The 2 patients in our series who presented with infarct had an extremely rapid downward course (subfulminant hepatic failure). It has been proposed that occlusion of the intrahepatic portal veins leads to the development of parenchymal extinction in cirrhosis 14 ; infarcts observed in BCS may represent the acute form of parenchymal extinction.…”

The hepatic circulation in health and disease: Report of a single-topic symposium

“…This ischemic shrinking and infarction of acini has been termed ''focal parenchymal extinction.'' 100 When a large number of extinction lesions are present, the anatomic features of cirrhosis are invariably present. Cases of congestive cirrhosis, autoimmune hepatitis, viral hepatitis, and cholestatic hepatitides such as primary biliary cirrhosis and primary sclerosing cholangitis all provide histological evidence for the development of cirrhosis secondary to hepatic and portal vein phlebitis.…”

Bleeding and Clotting Disorders in Pediatric Liver Disease

“…The intrahepatic microthrombi are thought to play a role in the progression of fibrosis and to result in local ischemia. 19 Patients with FV Leiden have been shown to have a faster progression of hepatitis. 20 Tripodi et al have shown that the hypercoagulability of plasma from patients with cirrhosis appears to result from increased levels of FVIII and decreased levels of protein C. 21 Thrombomodulin does not down-regulate thrombin generation in plasma from chronic liver disease patients as effectively as it does in plasma from healthy subjects, contributing to the risk of thrombosis in liver disease 11,22 …”