Impact of Asymptomatic Superior Mesenteric Vein Thrombosis on the Outcomes of Patients with Liver Cirrhosis

The impact of asymptomatic superior mesenteric vein (SMV) thrombosis on the outcomes of cirrhotic patients remains uncertain. Nonmalignant cirrhotic patients who were consecutively admitted between December 2014 and September 2021 and underwent contrast-enhanced computed tomography/magnetic resonance imaging scans were screened. Portal venous system thrombosis (PVST) was identified. Death and hepatic decompensation were the outcomes of interest. Nelson-Aalen cumulative risk curve analysis and competing risk regression analysis were performed to evaluate the impact of asymptomatic SMV thrombosis and portal vein thrombosis (PVT) on the outcomes. Overall, 475 patients were included, of whom 67 (14.1%) had asymptomatic SMV thrombosis, 95 (20%) had PVT, and 344 (72.4%) did not have any PVST. Nelson-Aalen cumulative risk curve analyses showed that the cumulative incidences of death (p = 0.653) and hepatic decompensation (p = 0.630) were not significantly different between patients with asymptomatic SMV thrombosis and those without PVST, but the cumulative incidences of death (p = 0.021) and hepatic decompensation (p = 0.004) were significantly higher in patients with PVT than those without PVST. Competing risk regression analyses demonstrated that asymptomatic SMV thrombosis was not a significant risk factor for death (subdistribution hazard ratio [sHR] = 0.89, p = 0.65) or hepatic decompensation (sHR = 1.09, p = 0.63), but PVT was a significant risk factor for death (sHR = 1.56, p = 0.02) and hepatic decompensation (sHR = 1.50, p = 0.006). These statistical results remained in competing risk regression analyses after adjusting for age, sex, and Child-Pugh score. Asymptomatic SMV thrombosis may not influence the outcomes of cirrhotic patients. The timing of intervention for asymptomatic SMV thrombosis in liver cirrhosis should be further explored.