Inferior vena cava filter retrieval

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Inferior vena cava filter retrieval is an endovascular procedure whereby a previously placed inferior vena cava (IVC) filter is removed.

Procedure

The procedure is performed under local anesthesia with fluoroscopic guidance. Venous access is usually gained via the internal jugular vein with direct sonographic visualization (unless the filter apex is oriented caudally, in which case femoral access may be necessary). Contrast administration can help to identify filling defects within the vena cava indicating thrombi .

The standard technique for filter removal involves the use of a sheath and snare to secure and retrieve the IVC filter from a hook located at its' apex, this subsequently collapses the filter and retracts it into the sheath, allowing for removal.

Pre retrieval CT may aid in procedure planning for filters that have had a long dwell time .

Modified techniques and considerations for complications have also been discussed in the literature .

  • filter tilt
    • a curved sheath can aid in directing the snare and engaging the filter hook.
  • filter hook embedded into a vessel (+/- associated fibrin cap) 
    • loop and snare technique: A curved catheter is advanced past the filter and a wire is advanced from the caudal end, the wire is then manipulated so that a loop is formed which can help to dislodge and sheath the filter.
    • fibrin cap removal: A wire loop can be formed around the fibrin cap, helping to dislodge it, and the filter from the vessel wall.
    • endobronchial forceps: can be utilized to grip and manipulate the filter.
  • filter legs embedded into the vessel
    • laser ablation sheaths (off label use): A sheath that is advanced over the filter with subsequent ablation of the vessel wall where hyperplastic tissue has formed around the filter legs. This approach may increase the risk of acute thrombosis
  • filter perforating IVC
    • assessment of potential procedural damage to adjacent structures before removal.
  • extensive thrombus around filter
    • continuation of anticoagulation and delay of filter removal could be considered.
    • mechanical thrombectomy may be used for acute thrombus.
  • fracture and embolization
    • endovascular retrieval of fragments may be necessary

Complications

Complications during removal are more likely when there are pre-existing complications of the filter in situ. Procedural complications could include :

  • complications from venous access:
  • retrieval failure
  • component fracture and embolization
    • embolization to the heart can cause arrhythmia
  • perforation of vena cava and acute hemorrhage
  • acute thrombosis of vena cava

History

With the emergence of optionally retrievable IVC filter technology, the placement of IVC filters has increased over time. Increasing evidence suggests that longer 'dwell time' of filters increases the incidence of related complications such as device fracture, vena cava perforation, filter migration, filter fragment embolization, and IVC thrombosis. Despite this, filter retrieval rates remain low at around 8.5% - 34%, with sub-optimal, follow up playing a large role. While filter retrieval is generally successful in filters with short dwell times, retrieval failure becomes more likely as the dwell time increases.