Changing perspectives in portal vein thrombosis

The aetiology of portal vein thrombosis (PVT) is heterogeneous. Important p rimary risk factors for PVT are cirrhosis. hepatobiliary malignancies and p ancreatitis. Newly discovered thrombotic risk factors, such as latent myelo proliferative disorders acid prothrombotic genetic defects, have also been identified as major risk factors for PVT. At least one-third of PVT patient s demonstrate a combination of thrombotic risk factors. PVT, which does not have a detrimental effect on liver function, usually becomes manifest as a variceal haemorrhage in the oesophagus months to years after the developme nt of thrombosis. Owing to intact coagulation variceal bleeding has a bette r prognosis among patients with PVT than cirrhotics. Endoscopic sclerothera py or band ligation is the primary therapeutic option for variceal bleeding in patients with PVT. It is questionable whether anticoagulant therapy sho uld be started, since it has not proven beneficial for most PVT patients. T herapy with anticoagulants is only recommended for those with acute PVT (es pecially in association with mesenteric vein thrombosis). those who recentl y underwent a portosystemic shunt procedure, and those with other thromboti c manifestations, particularly in case of proven hypercoagulability. Mortal ity of patients with PVT may be associated with concomitant medical conditi ons which lead to the PVT or with manifestations of portal hypertension, su ch as variceal haemorrhage. Multivariate analysis of a large Dutch PVT popu lation has shown that age, malignancy, ascites and the presence of mesenter ic vein thrombosis are independently related to survival. Death due to a va riceal haemorrhage is rare. Poor outcome of PVT thus appears to be associat ed primarily with concomitant diseases which lead to PVT, and not the compl ications of portal hypertension. It is therefore uncertain whether surgical portosystemic shunting affects survival favourably.