IVCfilter

An inferior vena cava (IVC) filter is a small, cage-like device implanted in the inferior vena cava to capture large blood clots traveling from the legs or pelvis, with the aim of preventing pulmonary embolism in patients who cannot be safely anticoagulated or who are at high risk of clot migration.

Placement and types: The filter is inserted through a percutaneous venous access, typically via the femoral or internal jugular vein, and positioned in the IVC below the renal veins. Filters are available in permanent designs and retrievable variants. Retrievable filters are intended to be removed when anticoagulation can be started or the short-term PE risk has subsided, after which the device is assessed for removal.

Indications: IVC filters are proposed for patients with a contraindication to anticoagulation, recurrent PE despite anticoagulation, or a temporary high risk of PE (for example after major trauma or surgery) when medical therapy is not suitable or sufficient. They may also be used in specific clinical scenarios guided by clinician judgment.

Procedure and follow-up: Placement is performed under imaging guidance, and post-procedure imaging confirms position. Retrievable filters require planned follow-up to evaluate the ongoing need and to arrange removal if feasible.

Risks and limitations: Complications can include filter migration, fracture, penetration of the IVC wall or adjacent structures, caval or filter thrombosis, infection, and difficulties with retrieval. Long-term retention of a permanent filter may be associated with increased lower-extremity DVT risk or caval occlusion in some patients. Effectiveness varies by patient and indication; an IVC filter reduces the risk of PE but does not eliminate it and is not a substitute for anticoagulation when anticoagulation is appropriate.

Alternatives: Anticoagulation remains the mainstay for venous thromboembolism prevention and treatment; mechanical approaches or alternative imaging-guided therapies may be considered in select cases.