One Year Outcomes of the VIVO-EU Study of Treatment of Symptomatic Iliofemoral Outflow Obstruction with the Zilver Vena Venous Self-Expanding Stent.

OBJECTIVE: To evaluate the performance of the Zilver® Vena™ Venous Stent in the treatment of patients with symptomatic iliofemoral outflow obstruction. METHODS: Between August 2012 and January 2015, 35 patients (mean age of 45.1 ± 15.5 years; 77.1% female) with symptomatic iliofemoral venous outflow obstruction were treated with the Zilver Vena Venous Stent (Cook Ireland, Ltd.) as part of this prospective, single arm, multicenter study. Study assessments included procedural success, major adverse events (MAEs), freedom from occlusion and qualitative patency at 6 and 12 month post-procedure, clinical symptoms of venous insufficiency, and reintervention with the treated venous segment. RESULTS: The rate of freedom from occlusion at 6 month and 12 month was 88.2%. The rate of qualitative patency was 88.2% at 6 month and 85.2% at 12 month. Three MAEs were reported: one symptomatic pulmonary embolism and two clinically-driven reinterventions. Following stenting, clinical symptoms of venous insufficiency improved significantly from baseline at each follow-up, as measured by VDS (p < 0.0001), CEAP "C" (p ≤ 0.0001), VCSS (p < 0.0001), and CIVIQ (p < 0.0001). CONCLUSION: Clinical results with the Zilver Vena Venous Stent were favorable through 12 month, with high patency rates, reduction of venous insufficiency symptoms, and low morbidity.

Short- and long-term retrievability of the Celect vena cava filter: results from a multi-institutional registry.

PURPOSE: To evaluate retrievability of the Celect vena cava filter over time and to assess the safety of the retrieval procedure in a prospective multicenter registry. MATERIALS AND METHODS: Between October 2005 and March 2008, Celect filters were placed in 95 patients (61 men; mean age, 51 years +/- 18.5) with a temporary need for an inferior vena cava (IVC) filter. All patients satisfied requirements for filter placement; the primary indications for placement were pulmonary embolism (PE) with a contraindication to or failure of anticoagulation (n = 40), high risk for further PE (n = 29), trauma (n = 23), or massive PE with residual deep vein thrombosis and risk for further PE (n = 3). Filter orientation, vena cava injury, and other device-related incidents were evaluated at implantation and retrieval. The degree of difficulty associated with retrieval was also assessed. RESULTS: Filter retrieval was attempted in 58 patients (mean indwell time of 179 days; median, 168.5 d; range, 5-466 d). Fifty-six filters (96.6%) were successfully retrieved. Unsuccessful retrieval attempts were attributed to filter tilt (n = 1) or excessive tissue growth with the hook embedded in the endothelium (n = 1). No adverse events were associated with the inability to retrieve these filters. A Kaplan-Meier product-limit survival estimate revealed that the probability of successful filter retrieval remained at 100% at 50 weeks and at more than 74% at 55 weeks after implantation. No adverse events were related to the retrieval procedures. CONCLUSIONS: Retrieval of the Celect filter was performed safely as long as 466 days after implantation.

Long-term retrieval success rate profile for the Günther Tulip vena cava filter.

PURPOSE: To evaluate the likelihood of successful retrieval of the Günther Tulip vena cava filter after various implant durations (up to 494 days). MATERIALS AND METHODS: Retrievable Günther Tulip filters were placed in 554 patients. All patients satisfied 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. RESULTS: Filter retrieval was attempted in 275 patients and 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 in-growth 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 two had no reported endpoint data. A Kaplan-Meier product-limit survival estimate revealed that the probability of successful device retrieval remained greater than 94% at 12 weeks and greater than 67% at 26 weeks. CONCLUSIONS: 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.

Deployment performance and retrievability of the Cook Celect vena cava filter.

PURPOSE: To test the safety, performance, and retrievability of the Cook Celect vena cava filter. MATERIALS AND METHODS: Twenty female or castrated male sheep were implanted with two Celect filters in series, in the inferior vena cava. The animals were divided into five groups of four animals according to day of filter retrieval. Filter retrieval occurred at approximately 30, 60, 90, 180, and 360 days after implantation. At each time point, two sheep underwent retrieval attempts of both the cranial and caudal filters. These animals were recovered for 30 days, at which time healing was assessed. In two additional sheep at each time point, retrieval of only the cranial filter was attempted and the caudal filter was left in situ. These sheep were euthanized after retrieval, and the segment of vena cava encompassing the sites of both the retrieved filter and the filter left in situ was excised for gross and histopathologic analysis. RESULTS: Retrieval attempts occurred at 34, 62, 90, 188, and 393 days after implantation. All retrievals were successful (30 of 30). Tilt was detected in eight filters at implantation; six had self-centered before retrieval. At retrieval, no filter migration or deformation was reported. All filters were retrieved with acceptable levels of force. At each time point, there was evidence of mild intimal hyperplasia at the filter anchoring sites and no evidence of vena cava injury. CONCLUSIONS: The Celect vena cava filter was safely used as a retrievable filter for up to 393 days in an ovine model.