The Clinical Rationale for the Sentry Bioconvertible Inferior Vena Cava Filter for the Prevention of Pulmonary Embolism.

The Sentry inferior vena cava (IVC) filter is designed to provide temporary protection against pulmonary embolism (PE) during transient high-risk periods and then to bioconvert after 60 days after implantation. At the time of bioconversion, the device's nitinol arms retract from the filtering position into the caval wall. Subsequently, the stable stent-like nitinol frame is endothelialized.

Deformation of the Femoropopliteal Segment: Effect of Stent Length, Location, Flexibility, and Curvature.

Purpose: To quantify the deformation behavior of the diseased femoropopliteal segment and assess the change to deformation behavior due to various stent placements.

Methods: The length and curvature changes of 6 femoropopliteal segments (the right and left superficial femoral and popliteal arteries) from 3 cadavers were measured in 3-dimensional space based on rotational angiography image data in straight leg and flexed hip/knee (50°/90°) positions before and after placement of nitinol stents of varying type (EverFlex, Misago, and BioMimics 3D) and length (60, 100, and 200 mm) in different locations along the arteries. Three-dimensional centerline data were extracted for the measurements.

Durable Clinical Effectiveness With Paclitaxel-Eluting Stents in the Femoropopliteal Artery: 5-Year Results of the Zilver PTX Randomized Trial.

Background: This randomized controlled trial evaluated clinical durability of Zilver PTX, a paclitaxel-coated drug-eluting stent (DES), for femoropopliteal artery lesions. Outcomes compare primary DES versus percutaneous transluminal angioplasty (PTA), overall DES (primary and provisional) versus standard care (PTA and provisional Zilver bare metal stent [BMS]), and provisional DES versus provisional BMS.

Methods And Results: Patients with symptomatic femoropopliteal artery disease were randomly assigned to DES (n=236) or PTA (n=238).

The RETRIEVE trial: safety and effectiveness of the retrievable crux vena cava filter.

Purpose: To evaluate the safety and effectiveness of the Crux vena cava filter in patients at risk for pulmonary embolism (PE).

Materials And Methods: The Crux Biomedical Evaluation of the Crux Inferior Vena Cava Filter System trial was an international prospective, multicenter, single-arm clinical trial in 125 patients implanted with the Crux filter between June 2010 and June 2011. Follow-up was 180 days after filter placement and 30 days after filter retrieval.

Sustained safety and effectiveness of paclitaxel-eluting stents for femoropopliteal lesions: 2-year follow-up from the Zilver PTX randomized and single-arm clinical studies.

Objectives: A prospective, multinational randomized controlled trial (RCT) and a complementary single-arm study evaluated the 2-year safety and effectiveness of a paclitaxel-coated drug-eluting stent (DES) in patients with superficial femoral artery lesions. The RCT compared the DES with percutaneous transluminal angioplasty (PTA) and provisional bare-metal stent (BMS) placement.

Background: Local drug delivery for superficial femoral artery lesions has been investigated with the intent of limiting restenosis similarly to DES for the coronary arteries.

Nine-month results of the REFORM study: a prospective, single-arm, multicenter clinical study of the safety and effectiveness of the Formula™ balloon-expandable stent for treatment of renal artery stenosis.

Objectives: To evaluate the 9-month safety and effectiveness outcomes of the Formula™ balloon-expandable renal stent (Cook Medical, Bloomington, IN) for the treatment of atherosclerotic renal artery stenosis (RAS) following suboptimal angioplasty.

Background: Atherosclerotic RAS can cause hypertension and ischemic nephropathy. When clinically indicated, an interventional approach with renal angioplasty and stent implantation is the preferred method for revascularization of atherosclerotic renal artery stenoses.

Paclitaxel-eluting stents show superiority to balloon angioplasty and bare metal stents in femoropopliteal disease: twelve-month Zilver PTX randomized study results.

Background: Sustained benefits of drug-eluting stents in femoropopliteal arteries have not been demonstrated. This prospective, multinational, randomized study was designed to compare the 12-month safety and effectiveness of a polymer-free, paclitaxel-coated nitinol drug-eluting stent (DES) with percutaneous transluminal angioplasty (PTA) and provisional bare metal stent (BMS) placement in patients with femoropopliteal peripheral artery disease.

Methods And Results: Patients were randomly assigned to primary DES implantation (n=236) or PTA (n=238).

TASC II and the endovascular management of infrainguinal disease.

The stratifications of aortoiliac, femoropopliteal, and infrapopliteal lesions included in the original comprehensive report of the TransAtlantic Inter-Society Consensus (TASC I) have been commonly used to formally characterize clinical trial populations and to channel investigative discussion among clinicians, while the associated treatment recommendations have become outdated as compared to current clinical practice. The TASC II report is an abbreviated update focusing on key areas of diagnosis and management of peripheral artery disease, with revised stratifications of aortoiliac and femoropopliteal lesions but not infrapopliteal disease. The consensus document keeps new lesion stratifications linked to the same structure of recommendations for initial treatment: endovascular for type A, endovascular (with qualifications) for type B, open surgical (with qualifications) for type C, and open surgical for type D.

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).

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.

Fracture of self-expanding nitinol stents stressed in vitro under simulated intravascular conditions.

Objective: The use of intravascular stents in the superficial femoral artery (SFA) continues to be controversial due to the potential for compression and fracture in the tortuous physical environment of the adductor canal. The purpose of this study was to (1) characterize the types and ranges of stent distortion theoretically produced by extremity movement and (2) use these ranges as parameters for in vitro long-term fatigue testing of commercially available self-expanding nitinol stents.

Methods: Nitinol self-expanding stents were placed in the SFAs of cadavers and lateral view radiographs were obtained with the limb in various degrees of hip and knee flexion.

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.

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).

Paperwork for the busy interventionalist: the basic six.

Communication and patient care go hand in hand. Unfortunately, due to time constraints direct verbal communication with health care providers in every instance is not practical; it is also inefficient. Documentation is mandated by the Joint Commission on Accreditation of Healthcare Organizations and hospital bylaws.

Lessons learned on how to protect an interventional radiologist against malpractice claims.

Unfortunately, the risk of lawsuit is high for the interventional radiologist, especially for the one who assumes a more active clinical role in the care of patients. The importance of assuming this guardianship role in patient care is paramount to building an active referral base for reasons given in several accompanying articles in this issue. Because of added malpractice risks, it is important to fully understand the risks of this clinical role and how to protect yourself from potential lawsuits.

The Basics of Interventional Radiology Management in a Large Radiology Group: A Bird's-Eye View.

Through nearly 6 decades of growth we have enjoyed and suffered under many different types of management structures. From these experiences we have become believers in a central committee structure that advances our agenda with hospital administrators and third-party payers. The best way to illustrate what we think is a winning solution is by describing our present management system.

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.

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.

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.

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.

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.