My Mother Had Gone Through A Sleeve Gastrectomy Operation 3

My mother had gone through a sleeve gastrectomy operation 3 weeks ago. On the 22nd post-operative day, due to severe pain in the epigastric zone, her doctor ordered an abdominal CT and it turned out that portal vein and superior mesenteric vein were thrombosed. They put her on enoxaparin and wanted her to rest for 5 days until the next control.

I read somewhere that enoxaparin only prevents further occlusion of the vein and does not lyse existing clot. Should we consider thrombectomy A.S.A.P?