Natural history and predictors associated with the evolution of portal venous system thrombosis in liver cirrhosis

Portal venous system thrombosis (PVST) will progress in some cases, indicating worse outcome and the necessity of antithrombotic treatment, but will spontaneously improve in others. It is crucial to understand the natural history of PVST in liver cirrhosis. However, the knowledge regarding how to predict the evolution of PVST in cirrhotic patients is very scant.Sixty-nine cirrhotic patients without malignancy, who had undergone repeated contrast-enhanced computed tomography or MRI to evaluate the severity of PVST at the first and last admissions, were included. Logistic regression analysis was performed to identify the risk factors for the evolution of PVST in liver cirrhosis. Odds ratios (ORs) were calculated.Among 42 patients without PVST at the first admission, 10 (23.8%) developed PVST at the last admission. Serum albumin level (OR = 0.873), prothrombin time (OR = 1.619), activated partial thromboplastin time (OR = 1.169), Child-Pugh score (OR = 1.560) and model for end-stage liver disease (MELD) score (OR = 1.292) at the last admission were significant risk factors associated with the development of PVST. Among 27 patients with PVST at the first admission, 11 (40.7%), 4 (14.8%) and 12 (44.4%) had improvement, stabilization and progression of PVST at the last admission, respectively. ΔMELD score (OR = 0.714) was the only significant risk factor associated with the improvement of PVST; additionally, serum albumin level at the first admission (OR = 1.236) was the only significant risk factor associated with the progression of PVST.Aggravation and amelioration of liver dysfunction may predict the development and improvement of PVST in liver cirrhosis, respectively.