Predicting portal thrombosis in cirrhosis: Some issues

Abstract

We read with great interest the excellent manuscript based on a prospective study recently published by Turon F et al. 1 In the 369 patients with cirrhosis without portal vein thrombosis (PVT), 29 patients developed non-tumoral PVT with reported incidences of 1.6%, 6.0% and 8.4% at 1, 3 and 5 years, respectively. In evaluating the incidence and risk factors for PVT development, the authors have concluded that platelet count, decreased portal blood flow velocity (PBFV) (<15 cm/sec) and history of variceal bleeding, rather than acquired or inherited hemostatic disorders and inflammatory status, were factors independently associated with a high PVT risk. We raise some concerns which may need further consideration.First, the levels of the pro-coagulant Factor X have been shown to be an independent risk factor in subgroup analyses. In addition to other important factors, 2 such as hereditary deficiency of protein C, S or antithrombin among 310 patients in this cohort, Factor X might have been overlooked in the authors' conclusions. PVT is a frequent complication of cirrhosis, particularly in patients with moderate-severe liver failure. 3 It is worth exploring whether the different roles of the levels of the procoagulant Factor X in patients with different portal flow velocities exist. We recommend assessing the impact of acquired or hereditary hemostatic parameters, such as the levels of the procoagulant Factor X and inflammatory parameters, in groups of patients stratified by portal flow velocities or splenic length.Second, patients undergoing surgical procedures such as splenectomy, 4,5 devascularization for the treatment of portal hypertension 6 or liver transplantation, 7 which have been reported as significant independent risk factors for PVT in patients with cirrhosis, were excluded in the prospective study. 1 It is also essential to assess the risks of PVT in patients undergoing surgical procedures who were absent from this outstanding report by Turon F et al.