Multicenter Trial of the VenaTech Convertible Vena Cava Filter.

PURPOSE: To demonstrate rates of successful filter conversion and 6-month major device-related adverse events in subjects with converted caval filters. MATERIALS AND METHODS: An investigational device exemption multicenter, prospective, single-arm study was performed at 11 sites enrolling 149 patients. The VenaTech Convertible Vena Cava Filter (B. Braun Interventional Systems, Inc, Bethlehem, Pennsylvania) was implanted in 149 patients with venous thromboembolism and contraindication to or failure of anticoagulation (n = 119), with high-risk trauma (n = 14), and for surgical prophylaxis (n = 16). When the patient was no longer at risk for pulmonary embolism as determined by clinical assessment, an attempt at filter conversion was made. Follow-up of converted patients (n = 93) was conducted at 30 days, 3 months, and 6 months after conversion. Patients who did not undergo a conversion attempt (n = 53) had follow-up at 6 months after implant. RESULTS: All implants were successful. One 7-day migration to the right atrium required surgical removal. Technical success rate for filter conversion was 92.7% (89/96). Mean time from placement to conversion was 130.7 days (range, 15-391 d). No major conversion-related events were reported. The mean conversion procedure time was 30.7 minutes (range, 7-135 min). There were 89 converted and 32 unconverted patients who completed 6-month follow-up with no delayed complications. CONCLUSIONS: The VenaTech Convertible filter has a high conversion rate and low 6-month device-related adverse event rate. Further studies are necessary to determine long-term safety and efficacy in both converted and unconverted patients.

Safety and efficacy of alteplase for restoring function in occluded central venous catheters: results of the cardiovascular thrombolytic to open occluded lines trial.

PURPOSE: To evaluate the safety and efficacy of alteplase (TPA) for restoring function to occluded central venous catheters (CVCs). PATIENTS AND METHODS: The study design was a phase III, open-label, single-arm multicenter trial. Subjects with occluded, nondialysis CVCs were enrolled. All subjects received a 2-mg dose of TPA within the dysfunctional catheter lumen that was allowed to dwell for 30 to 120 minutes. Functionality was tested at 30 and 120 minutes. If the CVC remained obstructed at 120 minutes, a second 2-mg TPA dose was allowed to dwell for 30 to 120 minutes. The primary safety end point was the rate of intracranial hemorrhage (ICH) within 5 days of treatment, and serious adverse events were recorded up to 30 days. RESULTS: Nine hundred ninety-five patients received treatment (female, 562; male, 433; mean age, 50.7 years; range, 2 to 91 years). CVCs treated were as follows: single (26%), double (39%), or triple (6%) lumen catheters or ports (29%). The primary end point was 0% ICH within 5 days. There were no cases of death, major bleeding episodes, or embolic events attributable to treatment. Flow was successfully restored in 52% and 78% of CVCs at 30 and 120 minutes after one dose, and 84% and 87% at 30 and 120 minutes after a second dose, respectively. Restoration of flow was 86%, 93%, 90%, and 79%, for single, double, and triple lumen catheters and ports, respectively. Estimated 30-day catheter patency was 74%. CONCLUSION: A regimen of up to two 2-mg doses of TPA is safe and effective for the restoration of flow to occluded central venous catheters.

Impact of resident call eligibility on major discrepancy rate.

RATIONALE AND OBJECTIVES: The Resident Review Committee (RRC) recently changed the policy concerning first-year resident call. Our study is intended to evaluate whether the additional 6 months of training before a resident's first call made a significant difference in the resident's ability to provide patient care. To evaluate this, we assessed the discrepancy rates between preliminary interpretations made by residents and final reports by attendings. MATERIALS AND METHODS: All cross-sectional imaging interpreted by on-call residents (5 PM to 8 AM) during the first 6 months of call duties was reviewed for discrepant findings between the preliminary resident report and the final interpretation by an attending. Only major discrepancies were evaluated. A major discrepancy was defined as a change made to the resident preliminary report by an attending radiologist where a delay in communicating that finding had the potential to negatively affect clinical outcomes. Major discrepancy rates between groups were then compared. RESULTS: During the second 6 months of the 2008-2009 academic year, first-year residents interpreted 3331 studies. Fifty-nine of those were declared to be discrepancies after an attending over-read, a rate of 1.8%. During the first 6 months of the 2009-2010 academic year, second-year residents interpreted 4649 studies with 49 discrepancies, a rate of 1.0%. This difference is statistically significant (P = .008). CONCLUSIONS: The recent RRC policy change requiring 6 additional months of training before assuming independent on-call responsibilities has significantly decreased the major discrepancy rate at our institution.

Reteplase infusion in the treatment of acute lower extremity occlusions.

PURPOSE: Reteplase, a recombinant tissue plasminogen activator, has been used in the treatment of acute coronary occlusion. Experience is accumulating regarding its use in the treatment of peripheral vascular disease. Increased experience with this thrombolytic agent may show that it can be an appropriate alternative agent to currently employed plasminogen activators. MATERIALS AND METHODS: Over the course of six months, reteplase was used to treat 18 patients with peripheral arterial occlusions, confined to the lower extremities. The agent was infused via "pulse-spray" catheters. Fifteen patients were started on 0.5 U/h. Concurrent heparin therapy was used at 500 U/h in 16 of 18 patients. RESULTS: The average total dose of reteplase infused was 13.3 units. It ranged from 6.2 to 41.5 units. The average duration of infusion was 26.9 hours with a range of 12-44 hours. Clinical success, defined as restoration of sufficient patency to reestablish limb function and resolution of pain in the symptomatic extremity was 89% (16 out of 18). Hemorrhagic complications occurred in five patients and were major in one patient (5%). No patient experienced intracranial hemorrhage. CONCLUSION: Increased experience with the use of reteplase in the treatment of acute lower extremity occlusions is accumulating. The safety and efficacy profile in our group appears satisfactory and compares to other studies. However, definite conclusions must await the results of controlled comparisons of different reteplase infusion regimens and controlled comparison to other thrombolytic agents.