Cook's Günther Tulip VCF Shows Long-Term Retrievability

July 2, 2009—In the Journal of Vascular and Interventional Radiology, H. Bob Smouse, MD, et al published findings from a study conducted to evaluate the likelihood of successful retrieval of the Günther Tulip vena cava filter (VCF) (Cook Medical, Bloomington, IN) after various implant durations of up to 494 days (2009;20:871–877).

Retrievable Günther Tulip VCFs were placed in 554 patients. All patients satisfied the requirements for filter placement. The primary indication for placement was specified for 394 patients (71%) as follows: unspecified trauma (n = 164), bariatric procedures (n = 128), orthopedic procedures (n = 36), and other (n = 66). Filter tilt and vena cava injury were assessed at implantation. Filters were not repositioned after placement. At retrieval, filter orientation, vena cava injury, other device-related incidents, and the degree of difficulty associated with retrieval were reported.

According to the investigators, VCF retrieval was attempted in 275 patients and was successful in 248 (90.2%). The mean filter indwell time was 58.9 days (range, 3–494 days). Unsuccessful retrievals (n = 27) were attributed primarily to improper hook orientation (n = 10) or excessive tissue ingrowth at the filter legs (n = 16). Of the remaining 279 patients, 223 withdrew from the study, 41 were associated with a decision to keep the filter as a permanent device, 13 died for reasons unrelated to the study, and 2 had no reported endpoint data. A Kaplan-Meier product-limit survival estimate revealed that the probability of successful device retrieval remained at > 94% at 12 weeks and > 67% at 26 weeks.

This study contributes to the body of clinical data related to retrievable filters demonstrating reliable retrieval rates at 12 weeks, with successful retrievals up to 17 months after implantation, the investigators concluded.