Use of a funneled sheath for embolic protection during removal of thrombosed Simon Nitinol filters

Inferior vena cava (IVC) filters should be removed when no longer needed, given their association with complications such as thrombosis of the IVC and lower extremities, fracture, migration, and growth into adjacent structures. While this is generally straightforward in the setting of retrievable filters, permanent filters present more of a challenge. In fact, many operators will not attempt to do so for fear of intraprocedural complications, among them, filter fracture and fragment embolization. Despite this, leaving the filters in situ places patients at risk of the complications described above. Here, the authors illustrate a novel technique for retrieving permanent filters using a funneled sheath to protect against embolization.