Purpose: To evaluate the retrievability and safety of the G2 filter.
Materials and Methods: A retrospective study of all G2 filter retrievals at a single institution was conducted. Hospital records and imaging studies we re reviewed for complications, and factors affecting retrieval were analyzed.
Results: From 2005 to 2009, a total of 139 patients presented for retrieval of their G2 filter, and 131 pairs of pre- and post-placement cavagrams and 39 computed tomography scans were available for analysis. The following findings were recorded: limb penetration (n 33), tilt greater than 15° (n 22), local migration greater than 2 cm (n 17), retained thrombus within the filter (n 16), deformity (n 10), inferior vena cava (IVC) occlusion (n 3), fracture (n 2), and pulmonary embolism breakthrough (n 2)A total of 118 filters were removed, with a mean indwelling time of 131.8 days (range, 3–602 d). Indwell time ( 90, 90–180, or 180 d)did not affect retrieval (P .4). There were 21 filters (15.1%) left in situ as a result of severe tilt (n 9), significant thrombus in the filter (n 5), IVC occlusion (n 3), filter incorporation into the caval wall (n 3), or lack of central venous access (n 1).There was a strong relationship between penetration and caudal migration (P .0001). Severe tilt was associated with prolonged fluoroscopic times for retrieval (P .003).
Conclusions: The majority of G2 filters can be removed without difficulty. The most common factor affecting retrieval was severe tilting. The indwellin g time had no impact on retrieval. G2 filter–related complications were frequent but most, including fractures, were clinically insignificant.