Portal Vein Thrombosis with Stent Follow-Up Imaging Protocol

Initial Post-Procedure Monitoring

Laboratory assessment the day after intervention should include transaminases, bilirubin, cholestasis parameters, coagulation studies, and complete blood count to detect early complications such as ischemic liver changes 1
Early Doppler ultrasound (within 7 days) is unreliable for covered stents due to acoustic barrier from the stent sheath, but can detect procedural complications before discharge 1, 2
For prothrombotic patients, confirmation of stent flow prior to discharge is specifically recommended 3, 4

Routine Doppler ultrasound examination at 4-6 weeks after stent creation is a strong recommendation with strong consensus 1, 2
Doppler ultrasound at 6-month intervals is recommended, which conveniently aligns with hepatocellular carcinoma screening schedules 1, 2, 3, 5
This frequency is based on the 44% dysfunction rate at 2 years even with covered stents, necessitating regular monitoring 1, 2

Maximum flow velocity at the portal vein should be monitored 1
Flow velocity within the stent tract should be monitored 1
Flow direction in intrahepatic portal vein branches should be monitored 1
Flow velocity in upstream portal vein and downstream hepatic vein should be monitored 1
Concerning findings suggesting stenosis include increased or decreased flow velocities within the shunt, decreased flow velocity in the portal vein trunk, and reversal of flow direction 1

Proceed with invasive transjugular imaging and portal pressure gradient measurement when Doppler ultrasound shows findings suspicious for dysfunction 1, 2
Clinical signs of failure, such as recurrent ascites or variceal rebleeding, are indications for invasive imaging 1, 6
The diagnostic sequence should be: Doppler ultrasound → angiography → portal pressure gradient measurement 1, 2

More intensive surveillance is warranted due to prothrombotic tendency 3, 4, 5
Consider routine scheduled portography within 1-2 months after portal vein recanalization to assess for residual thrombus, perform additional recanalization if needed, and embolize competing portosystemic shunts 6

Contrast-enhanced portal-venous CT angiography is the method of choice for anatomical visualization of the portal venous vascular axis 1
Perform CT angiography at 6-12 months to assess recanalization of the portal venous system 7, 8
MR Angiography can be used as alternative to CT angiography, but is less optimal due to metal artifacts making stenosis quantification difficult 1, 2

Ultrasound has only moderate specificity (33-95%) with high false positive rates (50%) for detecting stent dysfunction 6
Routine invasive imaging is NOT recommended except when dysfunction is suspected 1, 2, 5
Covered stents maintain patency >75% at 2 years versus >50% closure with bare stents 1, 2