VenaTech Convertible Vena Cava Filter 6 Months after Conversion Follow-up.

PURPOSE: To report device-related adverse events 6 months after placement or conversion of the VenaTech convertible vena cava filter (VTCF). MATERIALS AND METHODS: A review of 6-month follow-up data of an investigational device exemption multicenter, prospective, single-arm study was performed. The VTCF was implanted in 149 patients. Conversion was attempted in 64.4% of those patients (n = 96) and successfully in 96.9% of the patients (n = 93). A total of 76 patients completed imaging evaluation at 6 months after filter conversion. Patients who required continued venous thromboembolism prophylaxis at 6 months did not undergo a conversion attempt and were designated as nonconverted filter subjects. A total of 28 nonconverted filter subjects completed imaging evaluation at 6 months after implantation. RESULTS: Evaluation of patients at 6 months after conversion demonstrated 1 of 76 (1.3%) inferior vena cava (IVC) perforations with a filter strut greater than 3 mm outside of the caval lumen. No cases of recurrent PE, clinically significant filter migration, filter fracture, or IVC thrombosis were reported in the converted subjects. In the nonconverted filter subjects, there was a 14.3% (4 of 28) complete or nearly complete rate of IVC thromboses. There were no cases of recurrent pulmonary embolism, penetration, fracture, or spontaneous conversion in the nonconverted filter subjects. There was a significant reduction in the rate of IVC thrombosis and migration in the converted cohort compared to that in the nonconverted cohort. CONCLUSIONS: At 6 months, the VTCF demonstrated low adverse event rates in the converted configuration, whereas a minority of patients with the nonconverted configuration demonstrated a high risk of IVC thrombosis.