De novo Portal Vein Thrombosis in Virus-Related Cirrhosis: Predictive Factors and Long-Term Outcomes

OBJECTIVES: The objective of this study is to investigate predictive factors and long-term outcomes of de novo portal vein thrombosis (PVT) in cirrhosis. METHODS: The incidence and factors predictive of PVT (diagnosed by Doppler ultrasound) and prognosis were examined in 150 patients with virus-related cirrhosis but without PVT at baseline. RESULTS: PVT developed in 28% of patients (42/150), with cumulative incidence of 12.8%, 20%, and 38.7% at 1, 5, and 8-10 years, respectively. The baseline flow volume in the largest collateral vessel was an independent risk factor for thrombosis (hazard ratio, 3.922; 95% confidence intervals, 3.697-4.415; P < 0.0001). The cumulative incidence of PVT at 1, 5, and 10 years was significantly higher in patients with the largest collateral vessel velocity >10 cm/s (19.1%, 27%, and 78.4%, respectively) compared with those with velocity <= 10 cm/s (8.6%, 16.3%, and 24.7%, respectively, P = 0.0303), and higher in patients with volume >400 ml/min (27.4%, 36.5%, and 74.6%, respectively) compared with those with volume <= 400 ml/min (10.6%, 16.2%, and 28.8%, respectively, P = 0.0075). The natural course of thrombosis was improvement in 47.6%, unchanged in 45.2%, and worsened in 7.2%. The diameter and flow volume in the largest collateral vessel at the time of thrombus detection were significantly smaller in the improved patients than the others. The cumulative survival rate was similar between the thrombosis group and non-thrombosis group. CONCLUSIONS: Development of collateral vessels was a significant predictive factor for the occurrence of PVT in virus-induced cirrhosis. Spontaneous resolution or unchanged appearance was the most common outcome of thrombosis, which had little influence on prognosis.