Final Two-Year Outcomes for the Sentry Bioconvertible Inferior Vena Cava Filter in Patients Requiring Temporary Protection from Pulmonary Embolism.

PURPOSE: To report final 2-year outcomes with the Sentry bioconvertible inferior vena cava (IVC) filter in patients requiring temporary protection against pulmonary embolism (PE). MATERIALS AND METHODS: In a prospective multicenter trial, the Sentry filter was implanted in 129 patients with documented deep vein thrombosis (DVT) and/or PE (67.5%) or who were at temporary risk of developing DVT/PE (32.6%). Patients were monitored and bioconversion status ascertained by radiography, computed tomography (CT), and CT venography through 2 years. RESULTS: The composite primary 6-month endpoint of clinical success was achieved in 97.4% (111/114) of patients. The rate of new symptomatic PE was 0% (n = 126) through 1 year and 2.4% (n = 85) through the second year of follow-up, with 2 new nonfatal cases at 581 and 624 days that were adjudicated as not related to the procedure or device. Two patients (1.6%) developed symptomatic caval thrombosis during the first month and underwent successful interventions without recurrence. No other filter-related symptomatic complications occurred through 2 years. There was no filter tilting, migration, embolization, fracture, or caval perforation and no filter-related deaths through 2 years. Filter bioconversion was successful for 95.7% (110/115) of patients at 6 months, 96.4% (106/110) of patients at 12 months, and 96.5% (82/85) of patients at 24 months. Through 24 months of follow-up, there was no evidence of late-stage IVC obstruction or thrombosis after filter bioconversion or of thrombogenicity associated with retracted filter arms. CONCLUSIONS: The Sentry IVC filter provided safe and effective protection against PE, with a high rate of intended bioconversion and a low rate of device-related complications, through 2 years of follow-up.

One-Year Analysis of the Prospective Multicenter SENTRY Clinical Trial: Safety and Effectiveness of the Novate Sentry Bioconvertible Inferior Vena Cava Filter.

PURPOSE: To prospectively assess the Sentry bioconvertible inferior vena cava (IVC) filter in patients requiring temporary protection against pulmonary embolism (PE). MATERIALS AND METHODS: At 23 sites, 129 patients with documented deep vein thrombosis (DVT) or PE, or at temporary risk of developing DVT or PE, unable to use anticoagulation were enrolled. The primary end point was clinical success, including successful filter deployment, freedom from new symptomatic PE through 60 days before filter bioconversion, and 6-month freedom from filter-related complications. Patients were monitored by means of radiography, computerized tomography (CT), and CT venography to assess filtering configuration through 60 days, filter bioconversion, and incidence of PE and filter-related complications through 12 months. RESULTS: Clinical success was achieved in 111 of 114 evaluable patients (97.4%, 95% confidence interval [CI] 92.5%-99.1%). The rate of freedom from new symptomatic PE through 60 days was 100% (n = 129, 95% CI 97.1%-100.0%), and there were no cases of PE through 12 months for either therapeutic or prophylactic indications. Two patients (1.6%) developed symptomatic caval thrombosis during the first month; neither experienced recurrence after successful interventions. There was no filter tilting, migration, embolization, fracture, or caval perforation by the filter, and no filter-related death through 12 months. Filter bioconversion was successful for 95.7% (110/115) at 6 months and for 96.4% (106/110) at 12 months. CONCLUSIONS: The Sentry IVC filter provided safe and effective protection against PE, with a high rate of intended bioconversion and a low rate of device-related complications, through 12 months of imaging-intense follow-up.

Coding issues for interventional radiology: get paid for what you do!

As interventional radiology continues to evolve into a true clinical practice, more time will be spent on the clinical decision process; this time is reimbursable in the form of evaluation and management (E&M) services. Once assumed to be an inherent part of the procedure itself, we know many procedures now do not include follow-up E&M components. Unfortunately, E&M coding is somewhat complex and requires rigorous documentation. Below is a discussion of the fundamentals of E&M services, general principles of documentation, and the mechanics of coverage and reimbursement.

Using midlevel providers in interventional radiology.

Developing and implementing clinical services, including consultations, rounds, and clinic, is time-consuming, and for the interventional radiologist this means time away from the interventional laboratory. Using a team approach to providing clinical services is logical, and the midlevel provider is a perfect fit for an interventional radiology team. Midlevel providers can be grouped into two categories, advanced practice nurses (APNs) and physician's assistants (PAs). Under the umbrella of APN are several specialties including the nurse practitioner (NP), clinical nurse specialist (CNS), certified nurse midwife, and certified nurse anesthetist. The midlevel providers that are particularly suited for interventional radiology are the NPs, CNSs, and PAs. This article discusses midlevel providers in-depth including skills, limitations, and expenses.

Establishing surveillance clinics: the road to success.

Interventional radiology interacts with all medical disciplines and historically has not had a patient base of its own. The specialty has depended upon referrals for procedures (often complex) and not referrals for the global management of the disease process or patient. Because of this, when referrers develop catheter-based skills, referrals to interventional radiology drop and competition for primary care physician referrals increase; a double strike. To compete, interventional radiology needs to offer clinical services to the primary care physician. One way to compete is by establishing particular disease surveillance programs. Below we discuss in detail the process of establishing surveillance clinics, which one worked for us, and the expected outcomes of these clinics.

Differentiating pharmacologic agents used in catheter-directed thrombolysis.

The use of catheter-directed thrombolysis is a proven treatment for arterial ischemia, deep vein thrombosis, and severe pulmonary embolism. For arterial ischemia, thrombolysis has resulted in improved amputation-free survival and fewer subsequent surgeries to reestablish blood flow to the ischemic limb. The management of patients with thromboembolic diseases is complex, and the multiple thrombolytic drugs available to choose from compound this complexity. Although some believe the available thrombolytic agents are interchangeable, real biochemical differences exist that may prove otherwise. This article describes these pharmacologic differences and how they may affect the clinical practice of catheter-directed thrombolysis.

OptEase retrievable inferior vena cava filter: initial multicenter experience.

The purpose of this article is to describe our experience with the retrievable OptEase inferior vena cava filter (IVCF) (Cordis Corporation, Miami Lakes, FL) in the prevention of pulmonary embolus (PE). Forty patients (24 men, age range 15-85 years, mean age 38 years) who were at temporary risk of PE underwent insertion and retrieval of the OptEase IVCF at two institutions. Eleven patients were treated with filter implantation and subsequent repositioning in the inferior vena cava (IVC) to extend implantation time. All patients were followed up for 24 hours after retrieval, with additional follow-up at the physician's discretion. Forty patients had successful filter insertion. Two patients who underwent intravascular ultrasound guidance for filter deployment required filter repositioning within 24 hours owing to inadvertent placement in the right common iliac vein. All 40 patients underwent successful filter retrieval with no adverse events. In those patients who did not undergo IVCF repositioning, the time to retrieval ranged from 3 to 48 days (mean +/- SD 16.38 +/- 7.20 days). One patient had a successful retrieval at 48 days, but all other retrieval experiences were performed within 23 days. The second strategy involved implantation, with repositioning at least once before final retrieval. This latter strategy occurred in 11 patients, and the time to first capture ranged from 4 to 30 days (mean +/- SD 13.82 +/- 6.13 days). No symptomatic PE, IVC injury or stenosis, significant bleeding, filter fracture, or filter migration was observed. In this feasibility study, the OptEase IVCF prevented symptomatic PE, was safely retrieved or repositioned up to 48 days after implantation, and served as an effective bridge to anticoagulation. In patients who require extended IVCF placement, the OptEase IVCF can be successfully repositioned within the IVC, thereby extending the overall implantation time of this retrievable IVCF.

Transaxillary carotid stenting: technical case report.

OBJECTIVE AND IMPORTANCE: As endovascular neurointerventions continue to evolve rapidly, angioplasty and stenting of both the extracranial and intracranial vessels have become more routine procedures. When the transfemoral approach is contraindicated or technically difficult, familiarity with alternative access techniques becomes essential. We report a successful transaxillary carotid stenting in a patient with an axillary bifemoral bypass graft. CLINICAL PRESENTATION: A 77-year-old man presented with a symptomatic high-grade stenosis (80%) of the left internal carotid artery. Because of the increased risk of general anesthesia related to his advanced age and severe comorbidities, stenting of the left internal carotid artery was considered. A left transaxillary approach was chosen because of the presence of an axillary bifemoral bypass graft. TECHNIQUE: Under ultrasound guidance, the left axillary artery was successfully punctured and cannulated. After a 0.038 Magic Torque wire (Boston Scientific/Medi-Tech, Watertown, MA) was anchored with the tip of the wire in the distal left occipital artery, a 7-French (outer diameter) Vista Bright guiding sheath (Cordis, Miami, FL) was successfully positioned in the mid left common carotid artery, with an MPA catheter (Cordis) used as guiding support. Subsequently, two Precise stents (Cordis) were successfully deployed across the stenosis, yielding a satisfactory angiographic result. CONCLUSION: With proper patient selection and the use of ultrasound guidance during the initial puncture, the transaxillary approach is a safe and technically feasible alternative to the transfemoral approach when performing carotid stenting.

Gelatin sponge closure device versus manual compression after peripheral arterial catheterization procedures.

PURPOSE: To evaluate the safety and efficacy of the QuickSeal system, which delivers an over-the-wire extravascular porcine gelatin sponge (nonbovine and noncollagen), compared with manual compression in a single interventional radiology practice. MATERIALS AND METHODS: This single-institution report involves 141 patients undergoing peripheral diagnostic and interventional procedures in a teaching and private-practice setting. A 3:2 device-to-control ratio was used with randomization stratified by type of procedure, interventional or diagnostic. Primary endpoints included time to hemostasis (TTH), time to ambulation (TTA), and rate of major complications. Sheaths were removed in the device group when activated clotting times (ACTs) were < or =300 seconds for patients without glycoprotein (GP) IIb/IIIa platelet inhibitors and < or =250 seconds for patients with GP IIb/IIIa platelet inhibitors. Sheaths were removed in the control group when ACTs were < or =180 seconds. RESULTS: The mean TTH was significantly shorter (P <.001) in the device group (8.2 minutes) than in the control group (14.12 minutes). Mean TTA was shorter in the device group (2.7 hours) than in the control group (7.1 hours), and the time to discharge was shorter in the device group (23.8 hours) than in the control group (43.6 hours). There were no major complications in either group, and the incidences of minor complications were not significantly different. CONCLUSION: The tested device reduced TTH, TTA, and eligibility for hospital discharge while maintaining a safety profile equivalent to that of manual compression in diagnostic and interventional procedures.

Catheter-directed thrombolysis in deep venous thrombosis with use of reteplase: immediate results and complications from a pilot study.

PURPOSE: To prospectively determine the thrombolytic success and complication rates of catheter-directed thrombolytic infusions in deep vein thrombosis (DVT) with use of reteplase. MATERIALS AND METHODS: After approval by the institutional review board, prospective, detailed data were obtained for 25 consecutive patients with acute and chronic DVT of the upper or lower extremity (seven upper extremity; 14 lower extremity; four vena cava). Infusion rates were 1.0 U/h in five patients and 0.5 U/h in the remaining 20. Subtherapeutic heparin doses of 300-400 U/h were administered. Thrombolytic success was defined as 95% thrombolysis with return of antegrade flow. Data, including complications such as bleeding, need for transfusions, and laboratory values (fibrinogen, platelets, hematocrit, hemoglobin, and prothrombin time) were obtained throughout the infusions. RESULTS: The total dose of reteplase administered ranged from 2.5 to 42 U (median, 16.5 U). The total infusion time ranged from 0.3 to 84 hours (median, 29 h). Thrombolytic success was achieved in 92% of patients. Endovascular stent placement and/or percutaneous transluminal angioplasty were required in 52% of patients to ensure maintenance of patency. Pre- and postprocedural average fibrinogen levels were 340 mg/dL and 315.3 mg/dL, respectively. The lowest mean fibrinogen levels for the two dose groups were 265.86 mg/dL for the 0.5 U/h group and 314.18 mg/dL for the 1.0 U/h group. The lowest fibrinogen level during the procedure was 252.3 mg/dL (range, 35 to >700). There were only two instances of fibrinogen levels that decreased to below 90 mg/dL: 35 mg/dL and 43 mg/dL. Thrombolytic failures occurred in two patients: one with acquired immune deficiency syndrome in a hypercoagulable state and one with a major bleeding complication. This was the only patient with a bleeding complication (4%). Hemorrhage occurred from the site of a previous mediastinal biopsy-which should have rendered her ineligible for the study-performed 18 hours before the thrombolysis. If thrombolysis had not been attempted in this patient, the complication rate would have been 0%. CONCLUSION: Although there are reports of thrombolytic therapy in peripheral vascular occlusive disease, this study is one of the first to evaluate thrombolytic drugs in the deep venous system exclusively. Reteplase was found to be effective in the thrombolytic treatment of acute and chronic DVT.

Declining-dose study of reteplase treatment for lower extremity arterial occlusions.

PURPOSE: To prospectively determine the technical success and complication rates of three different reteplase dosing regimens during catheter-directed arterial thrombolysis. MATERIALS AND METHODS: Prospective data were obtained from three groups of patients who underwent lower extremity arterial thrombolysis with three different regimens of reteplase: 0.5 U/h, 0.25 U/h, and 0.125 U/h. A total of 101 thrombosed lower extremity arterial occlusions in 87 patients were treated. A subtherapeutic intravenous heparin dose of 400-500 U/h was administered. All limbs were viable at presentation. Thrombolytic success was defined as 95% thrombolysis of the occluded artery or graft with restored distal antegrade flow. Thirty-day mortality and amputation rates were calculated. Bleeding complications and need for transfusions were recorded. Laboratory values recorded included fibrinogen level, platelet count, hematocrit level, hemoglobin level, and prothrombin time. RESULTS: Thrombolytic success was achieved in 86.7% of patients in the 0.5-U/h dose group, 83.8% of patients in the 0.25-U/h dose group, and 85.3% of patients in the 0.125-U/h dose group. The major bleeding and transfusion rates were 13.3% in the 0.5-U/h dose group, 5.4% in the 0.25-U/h dose group, and 2.9% in the 0.125-U/h dose group. The 30-day amputation-free survival rates were 90% in the 0.5-U/h dose group, 97.3% in the 0.25-U/h dose group, and 94.1% in the 0.125-U/h dose group. Pre- and postprocedural fibrinogen levels and the fibrinogen nadir were not statistically different between the groups. No differences in total infusion times were found between the 0.5-U/h dose and 0.25-U/h dose groups. However, the infusion time in the 0.125-U/h dose group was significantly longer than in the other two groups (42 h vs 30 h; P <.05). CONCLUSION: All dosing regimens were equally effective in the treatment of acute lower extremity occlusions. The infusion times were longer with the 0.125-U/h dose. Significantly fewer major bleeding complications were encountered with the 0.25-U/h and 0.125-U/h dose regimens than with the 0.5-U/h dose regimen.

Treatment of pelvic arteriovenous malformations with ethylene vinyl alcohol copolymer (Onyx).

In this article, two successful embolizations of large pelvic arteriovenous malformations (AVMs) with use of ethylene vinyl alcohol, a radiopaque, nonadhesive liquid casting agent, are reported. Both patients presented with large symptomatic pelvic AVMs requiring therapy. Coaxial microcatheter techniques were used to achieve complete success in one case and partial success in the other. Clinical success has been maintained in both patients at 2-year follow-up.

Clinical practice of interventional and cardiovascular radiology: current status, guidelines for resource allocation, future directions.

The practices of interventional radiology and interventional neuroradiology are centered on high-quality direct patient care. These subspecialties have long histories of innovative care that has often revolutionized the treatment of disease and illness. More recently, however, this success has brought about competition from former referring physicians as they have gained access to technology and training that will enable them to obtain credentials for procedures that were formerly in the exclusive domain of interventionalists. Unfortunately, many interventional radiologists find themselves ill-equipped to compete for referrals. This is primarily because many interventional radiology practices lack complete clinical practices, which are critically important in facilitating referrals from the nonspecialists. Accordingly, this document details the critical importance of a complete clinical practice and further outlines the steps required to achieve this goal.