Prevalence and clinical consequences of fracture and fragment migration of the Bard G2 filter: imaging and clinical follow-up in 684 implantations.

PURPOSE

To investigate the prevalence and clinical sequelae of G2 filter (Bard Peripheral Vascular, Tempe, Arizona) fractures and fragment migration.

MATERIALS AND METHODS

Patients who underwent G2 filter placement between October 2005 and February 2010 were assessed for filter fractures and complications. Fracture prevalence was estimated at various time points based on data from patients with known fracture status.

RESULTS

Among 829 patients who underwent G2 filter placement, 684 had follow-up imaging and qualified for the study (381 men and 303 women; average age, 60.3 y; range, 15.8-95.2 y). For 541 (79%) patients, at least one image was available that contained the filter (imaging follow-up interval, 14.9 mo ± 20.0; range, 0-78.6 mo); images that did not include the filter but may have shown the migrated fracture fragment were available for 143 (21%) patients (follow-up interval, 11.2 mo ± 19.3; range, 0-83.4 mo). There were 16 fractured limbs identified in 13 patients (incidence, 1.9%; follow-up interval, 30.4 mo ± 18.7; range, 5.5-76.5 mo). Fracture fragments were identified in the pulmonary arteries (n = 4), right ventricle (n = 2), pericardium (n = 1), iliac vein (n = 1), and kidney (n = 1). Four fracture limbs remained near the filter; the remaining three could not be located. All patients with filter fracture were asymptomatic. The estimated 5-year fracture prevalence was 38% (95% confidence interval, 22.9%, 54.8%).

CONCLUSIONS

The early occurrence of G2 filter fractures was low, but the incidence increased over time. No life-threatening events occurred in patients with filter fracture during the study time frame.