Inferior Vena Cava filter insertion/retrieval

Inferior vena cava (IVC) filter insertion and retrieval are procedures designed to manage and mitigate the risk of pulmonary embolism (PE) in patients who cannot be adequately treated with anticoagulation therapy. These filters are placed in the inferior vena cava to trap emboli (blood clots) from the lower extremities, preventing them from traveling to the lungs.

Indications for IVC Filter Insertion

Absolute Indications:

• Contraindication to anticoagulation (e.g., active bleeding, recent surgery).
• Recurrent venous thromboembolism (VTE) despite adequate anticoagulation.
• Complications from anticoagulation (e.g., heparin-induced thrombocytopenia).

Relative Indications:

• Large free-floating proximal deep vein thrombosis (DVT).
• Severe cardiopulmonary disease and limited reserve.
• Prophylactic use in high-risk patients (e.g., trauma, major surgery).

Types of IVC Filters

1. Permanent Filters:
   • Designed to remain in the vena cava indefinitely.
   • Examples: Greenfield filter, Simon Nitinol filter.
2. Retrievable Filters:
   • Can be removed once the risk of PE has decreased.
   • Examples: Celect filter, Denali filter,  Option filter, Günther Tulip filter.

Procedure for IVC Filter Insertion

1. Pre-procedure Preparation:
   • Imaging: Pre-procedure imaging (ultrasound, venography, or CT) to assess the vena cava and identify the optimal placement site.
   • Patient Assessment: Review patient history, allergies, and current medications. Obtain informed consent.
2. Access Site Preparation:
   • Sterilization and Anesthesia: Sterilize the access site (commonly the right internal jugular vein or femoral vein) and administer local anesthesia.
   • Sheath Insertion: Insert a vascular sheath into the access vein.
3. Navigation and Deployment:
   • Guidewire and Catheter: Advance a guidewire and catheter to the IVC under fluoroscopic guidance.
   • Filter Deployment: Position the filter at the desired location (usually just below the renal veins) and deploy it. Verify placement with fluoroscopy.
4. Post-procedure Care:
   • Hemostasis: Achieve hemostasis at the access site using manual compression or closure devices.
   • Monitoring: Monitor the patient for any immediate complications, such as bleeding or filter migration.
   • Follow-up: Schedule follow-up visits to monitor the filter’s position and function.

Procedure for IVC Filter Retrieval

1. Pre-procedure Preparation:
   • Imaging: Evaluate the position and condition of the IVC filter using fluoroscopy, venography, or CT.
   • Patient Assessment: Review patient history, anticoagulation status, and ensure the filter is suitable for retrieval. Obtain informed consent.
2. Access Site Preparation:
   • Sterilization and Anesthesia: Sterilize the access site (usually the right internal jugular vein) and administer local anesthesia.
   • Sheath Insertion: Insert a vascular sheath into the access vein.
3. Retrieval Process:
   • Snare or Retrieval Device: Advance a retrieval snare or specialized retrieval device through the sheath to the filter under fluoroscopic guidance.
   • Capture and Retrieval: Capture the filter’s hook or apex with the snare, collapse it into the retrieval sheath, and withdraw it from the body.
   • Verification: Ensure complete removal and check for any complications or remnants using imaging.
4. Post-procedure Care:
   • Hemostasis: Achieve hemostasis at the access site using manual compression or closure devices.
   • Monitoring: Observe the patient for any immediate complications, such as bleeding or venous thrombosis.
   • Follow-up: Schedule follow-up visits to monitor for late complications and to assess the patient’s clinical status.

Benefits

• Prevents pulmonary embolism in high-risk patients.
• Minimally invasive with relatively quick recovery times.
• Retrievable filters offer temporary protection with the option of removal.

Risks

• Filter migration or fracture.
• Thrombosis at the insertion site or within the filter.
• Penetration of the IVC wall by the filter struts.
• Difficulty in retrieval, particularly with long-dwelling filters.
• Allergic reaction or infection at the access site.

Conclusion

IVC filter insertion and retrieval are crucial procedures in the management of venous thromboembolism for patients who cannot be effectively managed with anticoagulation alone. The choice between permanent and retrievable filters depends on the patient’s specific clinical situation and the anticipated duration of the risk of PE. Careful planning, precise execution, and diligent follow-up are essential to minimize complications and ensure optimal patient outcomes.