Thrombosis after transjugular intrahepatic portosystemic shunt: an ominous sign?

Abstract

Transjugular intrahepatic portosystemic shunt (TIPS) is increasingly used for the treatment of complications of portal hypertension, especially variceal bleeding and ascites refractory to conventional therapy (1,2). Development of thrombosis after TIPS placement is an uncommon complication, which was reported to occur in only 3% to 10% of patients when bare stents were used in several large series (3-6). Thrombosis usually develops acutely either at the time the stent is being deployed or within several days of TIPS placement (2,6). The cause of the thrombosis may be leakage of bile into the shunt, hypercoagulable syndromes, stent mispositioning, suboptimal stent sites, or inadequate coverage of the TIPS tract with sufficient stent (2,7-12). The direct result of thrombosis development is occlusion of the TIPS device, blocking flow in the portal vein and directly resulting in the recurrence of the complication of portal hypertension in addition to potentially causing bowel ischemia as a result of venous congestion in cases of thrombosis extending into the splenic and mesenteric veins (7). Thrombosis can be identified by Doppler ultrasound and patency can be re-established by repeat catheterization (2,7). The development of acute thrombosis also can be effectively prevented by prophylaxis anticoagulation or using e-PTFE-coated stents (13,14). One randomized controlled trial (RCT) showed that use of phenprocoumon (an anticoagulant) was associated with a lower rate of complete occlusion within the first three months following TIPS placement (13). In the RCT by Bureau (14), no early thrombosis was observed in the e-PTFE covered stent-graft group (n=39) as compared with three cases in the covered stent-graft group (n=41). A recent RCT also showed that early thromboses were less frequent in patients receiving covered stent TIPS compared with those receiving bare stents (10/67 in bare stent group vs. 3/63 in the covered stent group) (15).