What’s Next in Workup for Portal Vein Thrombosis?

Portal vein thrombosis is often an ominous sign. What next for this patient with HCV cirrhosis?

A 60-year-old man with HCV cirrhosis and known esophageal varices presents with new onset ascites. An ultrasound in the emergency room reveals new portal vein thrombosis. 

Which of the following would you recommend?