Natural Course of Extrahepatic Nonmalignant Partial Portal Vein Thrombosis in Patients with Cirrhosis

Purpose: To define the natural course of extrahepatic nonmalignant partial portal vein thrombosis (PVT), including the progression from partial to complete PVT, in patients with cirrhosis who had undergone multidetector computed tomography (CT). Materials and Methods: This study was institutional review board and ethics committee approved. Written informed consent was obtained for each procedure. Forty-two consecutive patients with cirrhosis and untreated extrahepatic, nonmalignant partial PVT were followed up until the final clinical evaluation, liver transplantation, or death. Multidetector CT was used to evaluate the thrombus lumen occlusion, patent lumen area, thrombus area, total lumen area, and diameter of main portal vein, superior mesenteric vein, and splenic vein. Statistical analysis was performed with the Wilcoxon Mann-Whitney U test, chi(2) test, Wilcoxon matchedpairs signed-rank test, life-table analysis, Kaplan-Meier method, and log-rank test, as appropriate. Results: After a mean follow-up period of 27 months, partial PVT worsened in 20 (48%) patients, improved in 19 (45%), and was stable in three (7%). The Kaplan-Meier probability of episodes of hepatic decompensation at 1 and 2 years was 41% and 57%; probability of hospital admission for hepatic decompensation, 37% and 54%; and survival rates, 77% and 57%, respectively. There was no clear association between progression or regression of partial PVT and clinical outcome. Multivariate analysis showed that the Child-Pugh score at diagnosis was the only independent predictor of survival (hazard ratio, 1.97; 95% confidence interval: 1.19, 3.23; P = .007) and hepatic decompensation (hazard ratio, 1.51; 95% confidence interval: 1.18, 1.19; P = .001). Conclusion: Extrahepatic nonmalignant partial PVT improved spontaneously in 45% of patients with cirrhosis, and the progression of partial PVT was not associated with clinical outcome, which appeared to be dependent on the severity of cirrhosis. (C) RSNA, 2012