Transjugular portosystemic stent shunt reduction

Transjugular intrahepatic portosystemic shunt (TIPS) reduction or downsizing refers to a procedure aimed at decreasing the diameter or length of an existing TIPS shunt to alleviate complications or improve clinical outcomes. 

Indications for TIPS Reduction

1. High TIPS Flow or Shunt Dysfunction: When the TIPS shunt is associated with high flow rates leading to complications such as hepatic encephalopathy, refractory ascites, or hepatorenal syndrome.
2. Symptomatic TIPS Stenosis or Occlusion: When there is significant stenosis or occlusion within the TIPS shunt resulting in portal hypertension-related symptoms or complications.
3. Improving Hepatic Function: In cases where reducing the TIPS diameter or flow can improve liver function or decrease the risk of complications.

Pre-procedure Preparation

1. Patient Evaluation:
   • Comprehensive assessment of the patient’s medical history, symptoms, liver function tests, imaging studies (such as Doppler ultrasound, CT scan, or MRI), and coagulation profile.
   • Evaluation of TIPS patency, flow rates, and any associated complications or symptoms.
2. Informed Consent:
   • Explanation of the TIPS reduction procedure, its purpose, potential risks (such as bleeding, infection, shunt dysfunction, or recurrence of symptoms), benefits, and alternatives. Informed consent is obtained.

Procedure Steps

1. Access and Catheterization:
   • The procedure is typically performed under local anesthesia and conscious sedation or general anesthesia, depending on the patient’s condition and tolerance.
   • Access is gained through the right internal jugular vein or femoral vein, and a catheter is advanced into the hepatic vein to access the TIPS shunt.
2. Venography and Imaging:
   • Contrast angiography or venography is performed to visualize the TIPS shunt, assess for stenosis or dilation, and determine the appropriate reduction strategy.
   • Imaging modalities such as intravascular ultrasound (IVUS) or pressure measurements may be used to assess TIPS flow rates, pressures, and patency.
3. TIPS Reduction Techniques:
   • Stent Reducer: Involves placing a smaller diameter stent within the existing TIPS shunt to reduce flow rates and decrease shunt diameter.
   • Partial Shunt Occlusion: Involves deploying a balloon or plug to partially occlude the TIPS shunt, reducing flow rates and shunt diameter.
   • Stent Graft Placement: In cases of severe stenosis or occlusion, a new stent graft may be placed within the existing TIPS shunt to improve patency and reduce flow rates.
   • Balloon Angioplasty: May be used to dilate narrowed segments within the TIPS shunt before or after reduction procedures.
4. Post-procedure Assessment:
   • Contrast angiography or venography is performed post-reduction to confirm the effectiveness of the TIPS reduction, assess shunt patency, and evaluate for any residual stenosis or complications.

Benefits and Clinical Outcomes

• Symptom Relief: TIPS reduction can alleviate symptoms such as hepatic encephalopathy, refractory ascites, or hepatorenal syndrome associated with high flow TIPS or shunt dysfunction.
• Improved Liver Function: Reducing TIPS flow rates or diameter can improve liver function parameters and decrease the risk of hepatic decompensation.
• Complication Prevention: TIPS reduction may prevent complications such as hepatic encephalopathy, shunt thrombosis, or refractory ascites related to excessive shunt flow.

Risks and Considerations

• Bleeding: Risk of bleeding at the access site or within the venous system during the procedure.
• Shunt Dysfunction: Potential for recurrent shunt stenosis, occlusion, or dysfunction post-reduction, requiring further interventions.
• Hepatic Encephalopathy: Changes in TIPS flow rates or shunt patency may influence the risk of hepatic encephalopathy, necessitating close monitoring and management.

Follow-up and Long-term Management

1. Clinical Assessment:
   • Regular clinical assessments and monitoring of symptoms, liver function, and complications post-TIPS reduction.
2. Imaging Studies:
   • Follow-up imaging studies (such as Doppler ultrasound, CT scan, or MRI) to assess TIPS patency, flow rates, and any signs of recurrent stenosis or complications.
3. Medication:
   • Adjustment of medications (such as diuretics, beta-blockers, or ammonia-lowering agents) based on clinical response and liver function parameters.
4. Lifestyle Modifications:
   • Recommendations for dietary changes, fluid restriction, and management of hepatic encephalopathy or ascites as needed.

Conclusion

TIPS reduction or downsizing is a valuable procedure in managing complications or symptoms related to high flow TIPS or shunt dysfunction in patients with portal hypertension. Close collaboration between interventional radiologists and hepatologists is essential for planning and performing TIPS reduction procedures and optimising patient outcomes. Long-term monitoring, follow-up care, and adherence to treatment strategies are crucial for maintaining TIPS patency, managing complications, and improving overall liver health in patients with chronic liver disease.