Inferior Vena Cava Filter Insertion, Removal and Maintenance

LSU Interventional Radiologists are experienced in both insertion and removal of inferior vena cava (IVC) filters using minimally invasive techniques.  Our physicians are passionate about using their expertise to help patients select the best available management of IVC filters using advanced tools and techniques.  In-person discussion of IVC filter management with each patient is provided to educate and assist with decision making.  

Purpose 
Inferior Vena Cava (IVC) filters are potentially life-saving devices inserted and removed by Interventional Radiologists to prevent blood clots from traveling from the lower half of the body to the lungs, called a pulmonary embolism.

Design
IVC filters are small metallic devices that are inserted into the body while folded up like a miniature umbrella without fabric.  When filters are inserted through a catheter, their specialized metals allow the filter to open to the diameter of the inferior vena cava of the individual patient.  Filters attach to the vein wall with tiny anchoring hooks intended to prevent filter movement and special struts can help filters center themselves in the middle of the vein.  

Temporary IVC filters are made with small hooks that facilitate their removal from the body.  Bendable metallic struts are folded similar to folding an umbrella and the filter is able to be removed from the body through a small catheter similar to a drinking straw in thickness.  

Permanent IVC filters are designed to remain within patients for an extended period of time, sometimes for the remainder of a patient's life.  Their design differs in that the struts or frame of the filter minimizes pressure on the vein wall to prevent scarring or penetration through the vein.  

Indications for insertion
IVC filters are most commonly inserted in patients who have a deep vein thrombus (DVT) or who are at high risk for development of a DVT and cannot receive blood thinners to treat the clot.  Reasons patients cannot receive blood thinners are typically an upcoming surgery in which blood thinners could cause bleeding, a history of bleeding from the stomach or intestines or risk of bleeding from another disease process.

Insertion Procedure

IVC filter insertion is typically done with sedation medication to make the patient comfortable.  After numbing medication is administered, a small catheter is passed into a vein using a combination of ultrasound and X-ray imaging.  The filter is inserted through the catheter and opened in the inferior vena cava where it is checked under X-ray to ensure the proper position and function.  The catheter is then removed from the patient.  This minimally invasive procedure usually takes less than 30 minutes.  

Complications from Long Term Use of Temporary Filters

While temporary IVC filters can be life-saving, these filters are not intended to be used after patients begin taking blood-thinning medications and are considered low risk for development of a pulmonary embolism.  Uncommonly, the body can react to the filter by forming scar tissue around it, making removal of the filter more difficult.  Scar tissue may lead to narrowing of the vein and poor blood flow that produces leg swelling and skin ulcers.  Filters may move or fracture over time and pieces can travel into other parts of the body such as the heart and lungs.  When struts protrude through the vein into the spine, intestines and other blood vessels, they can cause chronic pain.  While these complications are frightening, management of filters through a specialist is intended to lower risk as much as possible based upon studies, advanced tools and experience.  

Indications for removal

When patients are considered low risk for DVT and pulmonary embolism, IVC filters are generally no longer needed.  Each patient is different and individual risks and benefits must be carefully reviewed.  Most commonly, patients who receive an IVC filter are candidates after they have begun taking blood-thinning medication.  

Removal Procedure

Minimally invasive filter removal is similar to IVC filter insertion.  Patients receive sedation medication and local anesthesia.  After a catheter has been inserted into the IVC, angiograms are performed to show the filter location and provide information used for selection of technique.  Typically filters are removed by folding the filter (similar to folding an umbrella) and the filter is then removed through the catheter.  For filters that have been in place for a long time, other tools make removal safer such as a laser to remove scar tissue.   After the catheter has been removed, patients recover from sedation and are discharged to their homes later that day.