RESULTS OF A MULTICENTER STUDY OF THE RETRIEVABLE TULIP VENA-CAVA FILTER - EARLY CLINICAL-EXPERIENCE

Purpose: To evaluate clinically a new, retrievable vena caval filter i n a multicenter study. Methods: The Tulip filter is a stainless steel half-basket that is suitable for antegrade or retrograde insertion via an 8.5 Fr introducer sheath. The filter can be retrieved via the jugu lar approach using an 11 Fr coaxial retrieval system. Forty-eight filt ers were implanted via the femoral approach and 38 via the jugular app roach in 83 patients. Follow-up examinations (plain films, color-coded duplex sonography) were performed up to 3 years after filter insertio n (mean 136 days) in 75 patients, Twenty-seven patients were screened by color-coded duplex sonography for insertion site thrombosis. Result s: An appropriate filter position was achieved in all cases. Insertion problems occurred in 3 cases; these were not due to the filter design but to an imperfect prototype insertion mechanism that has now been m odified (n = 2) or a manipulation error (n = 1). In 2 of these cases t he filters were replaced percutaneously; 1 patient required venotomy f or filter removal. No further complications due to filter insertion oc curred. Two filters were used as temporary devices and were success fu lly removed after 6 and 11 days, respectively. There was 1 fatal recur rent pulmonary embolism (PE) and 2 non-fatal PE, 5 complete and 3 part ial caval occlusions, and 3 caudal migrations of the filter. Insertion site venous thrombosis was not seen in the 27 patients monitored for this complication. Conclusion: Precise placement of the Tulip filter i s feasible by either access route and the device appears mechanically stable. Further observations are needed to confirm that safe filter re moval is practical up to 10 days after its insertion.