What is a percutaneous stainless steel Greenfield inferior vena cava (IVC) filter?

Updated: Oct 31, 2020
  • Author: Gary P Siskin, MD; Chief Editor: Kyung J Cho, MD, FACR, FSIR  more...
  • Print
Answer

Answer

Percutaneous stainless steel Greenfield filter

In the course of the continual improvement of the Greenfield filter design, a 12F stainless steel over-the-wire Greenfield filter was developed to provide a lower-profile introducing system. [11] The hook design was improved to prevent filter migration. The guidewire is used during deployment of the percutaneous steel Greenfield filter (PSGF) to provide a centering effect during filter release. Greenfield et al suspected that elimination of the guidewire may have been responsible for the high incidence of tilt of the TGF. The US Food and Drug Administration (FDA) approved the PSGF in 1995.

The PSGF, also called the stainless steel Greenfield filter with alternating hooks (SGF-AH), is manufactured from the same 316L-grade stainless steel as the original 24F SGF, and it retains the conical shape with 6 zigzag radiating legs. [15] The legs are welded to the apical bead, now at an angle of 0° as opposed to 17.5°. An opening in the center of the apical bead allows passage of a guidewire. The legs are 4.9 cm long (vs 4.7 cm for the TGF and 4.6 cm for the standard Greenfield filter). The base diameter is 3.2 cm (vs 3.8 cm for the TGF and 3.0 cm for the standard Greenfield filter). The system is preloaded differently for jugular and femoral approaches through a 12F carrier system.

Fluoroscopic control during withdrawal of the guidewire was recommended, because the guidewire can get caught between the legs near the apex or the hook. The not infrequent entrapment of guidewires was believed to result from the more crowded legs toward the apex with this new design. In 1998, Johnson et al reported that 21 (55%) of 38 patients had filter tilting of more than 15°, as evaluated with postplacement cavography and CT scanning. [16] The authors found a significant difference between filters placed via the jugular approach (12%) and filters placed via the femoral approach (51%). [16] Kinney et al also found that the right jugular approach resulted in the least filter tilt in their experience with 104 PSGF placements. [17]

In 2000, Greenfield et al reported the results of 600 PSGF placements in 599 patients. [18] Among patients receiving the PSGF with the modified hook, they found filter tilt in only 0.4%. Filter tilt was present in 5% of patients receiving the PSGF with standard hooks. Filter migration of more than 20 mm was seen in as many as 27% of PSGF placements with the standard hook but in less than 1% of the PSGF placements with alternating hooks. [18] Recurrent PE was reported to occur in 2% and 2.6% by Johnson et al and Greenfield et al, respectively. Greenfield et al reported a caval patency rate of 98% and a 4.3% rate of insertion thrombosis.


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!