T. Gregory Walker

Consensus guidelines for periprocedural management of coagulation status and hemostasis risk in percutaneous image-guided interventions.

From the Division of Vascular and Interventional Radiology, Jefferson Radiology, Hartford Hospital, 85 Seymour St, Ste 200, Hartford, CT 06106 (P.C.M.); Department of Radiology, Boston Healthcare System, VAMC Boston, Massachusetts (C.J.G.); Department of Medical Imaging, Scarborough General Hospital, Richmond Hill, Ontario, Canada (S.K.); Department of Radiology, GI/GU Division, Massachusetts General Hospital, Boston, Massachusetts (D.A.G.); Department of Radiology and Radiologic Sciences, Uniformed Services University of the Health Sciences and Department of Radiology, National Naval Medical Center, Bethesda, Maryland (D.L.M.); RADIA, Everett, Washington (R.B.O.); Department of Radiology, University of Florida, Gainesville, Florida (D.W.P.); Department of Medical Imaging, Division of Vascular and Interventional Radiology, University of Toronto, University Health Network, Toronto, Ontario, Canada (D.K.R.); Department of Interventional Radiology, The Reading Hospital and Medical Center, West Reading, Pennsylvania (D.S.); Radiology Associates of Central Florida, Mt Dora, Florida (M.S.S.); Mallinckrodt Institute of Radiology, St Louis, Missouri (D.A.Z.); and Geisinger System Radiology, Geisinger Health System, Danville, Pennsylvania (J.F.C.). Received November 18, 2008; accepted November 24, 2008. Address correspondence to P.C.M.; E-mail: pmalloy@ jeffersonradiology.com

Quality improvement guidelines for the treatment of lower-extremity deep vein thrombosis with use of endovascular thrombus removal.

Suresh Vedantham, MD, Patricia E. Thorpe, MD, John F. Cardella, MD, Chair, Clement J. Grassi, MD, Nilesh H. Patel, MD, Hector Ferral, MD, Lawrence V. Hofmann, MD, Bertrand M. Janne d’Othée, MD, Vittorio P. Antonaci, MD, Elias N. Brountzos, MD, Daniel B. Brown, MD, Louis G. Martin, MD, Alan H. Matsumoto, MD, Steven G. Meranze, MD, Donald L. Miller, MD, Steven F. Millward, MD, Robert J. Min, MD, Calvin D. Neithamer Jr., MD, Dheeraj K. Rajan, MD, Kenneth S. Rholl, MD, Marc S. Schwartzberg, MD, Timothy L. Swan, MD, Richard B. Towbin, MD, Bret N. Wiechmann, MD, and David Sacks, MD, for the CIRSE and SIR Standards of Practice Committees

Quality Improvement Guidelines for Diagnostic Arteriography

PREAMBLE The membership of the Society of Interventional Radiology (SIR) Standards of Practice Committee represents experts in a broad spectrum of interventional procedures from the private and academic sectors of medicine. Generally, Standards of Practice Committee member dedicate the vast majority of their professional time to performing interventional procedures; as such, they represent a valid, broad expert constituency of the subject matter under consideration for standards production.

Clinical Practice Guidelines for Endovascular Abdominal Aortic Aneurysm Repair: Written by the Standards of Practice Committee for the Society of Interventional Radiology and Endorsed by the Cardiovascular and Interventional Radiological Society of Europe and the Canadian Interventional Radiology Association

From the Department of Radiology, Division of Vascular Imaging and Intervention (T.G.W., S.P.K., K.Y., S.W.), Massachusetts General Hospital, Boston, Massachusetts; Department of Medical Imaging (S.K.), Scarborough General Hospital, Toronto, Ontario, Canada; Department of Interventional Radiology (P.D.), West Allis Memorial Hospital, Milwaukee, Wisconsin; Department of Radiology, Division of Interventional Radiology (B.J.D.), University of Maryland Medical Center, Baltimore, Maryland; Department of Radiology (S.C.R.), University of California San Diego Medical Center, San Diego, California; and Department of Radiology (J.F.C.), Geisinger Health System, Danville, Pennsylvania. Received May 4, 2010; final revision received May 24, 2010; accepted July 11, 2010. Address corre-

Natural History and CT Appearances of Aortic Intramural Hematoma

Rupture of the vasa vasorum into the media of the aortic wall results in an aortic intramural hematoma. Characteristic findings of an aortic intramural hematoma include a crescentic hyperattenuating fluid collection at unenhanced computed tomography (CT) and a smooth, nonenhancing, thickened aortic wall at contrast material-enhanced CT. The CT appearance of untreated intramural hematomas evolves over time, and decreased attenuation is a clue to the chronicity of a hematoma. CT is particularly useful for evaluating aortic intramural hematomas because it allows their differentiation from aortic dissections, which have similar clinical manifestations, and permits an exact determination of their location-crucial information for surgical planning. On the basis of CT findings, some hematomas may be expected to resolve spontaneously, whereas others may be identified as posing a high risk for serious complications such as aortic dissection, aneurysm, and rupture. Appropriate clinical management is aided by accurate recognition of diagnostically specific CT features and awareness of their significance.

Angiographic evaluation and management of acute gastrointestinal hemorrhage

Although most cases of acute nonvariceal gastrointestinal hemorrhage either spontaneously resolve or respond to medical management or endoscopic treatment, there are still a significant number of patients who require emergency angiography and transcatheter treatment. Evaluation with noninvasive imaging such as nuclear scintigraphy or computed tomography may localize the bleeding source and/or confirm active hemorrhage prior to angiography. Any angiographic evaluation should begin with selective catheterization of the artery supplying the most likely site of bleeding, as determined by the available clinical, endoscopic and imaging data. If a hemorrhage source is identified, superselective catheterization followed by transcatheter microcoil embolization is usually the most effective means of successfully controlling hemorrhage while minimizing potential complications. This is now well-recognized as a viable and safe alternative to emergency surgery. In selected situations transcatheter intra-arterial infusion of vasopressin may also be useful in controlling acute gastrointestinal bleeding. One must be aware of the various side effects and potential complications associated with this treatment, however, and recognize the high re-bleeding rate. In this article we review the current role of angiography, transcatheter arterial embolization and infusion therapy in the evaluation and management of nonvariceal gastrointestinal hemorrhage.

Addendum of Newer Anticoagulants to the SIR Consensus Guideline

Appropriate periprocedural management of the hematologic parameters in a patient undergoing percutaneous image-guided intervention is highly complex, considering the wide range of procedures and patient demographics. This is further complicated by both the use of short-term and long-term anticoagulants and the increasing use of antiplatelet agents and other medications. Unfortunately, there is currently a general paucity of objective medical data regarding the periprocedural management of patients with abnormal coagulation parameters. In the absence of strong evidence regarding periprocedural management of this patient category, members of the Standards of Practice Committee of the Society of Interventional Radiology (SIR) have proposed general recommendations that may be useful to the practicing interventionalist. The various classes of medications that affect patient coagulation parameters were critically reviewed. When the evidence of literature was weak, conflicting, or contradictory, consensus for the parameter was reached by a minimum of 12 Standards of Practice Committee members by using a modified Delphi consensus method (1). For the purposes of these documents, consensus is defined as 80% Delphi participant agreement on a value or parameter. A time lapse of 5 half-lives of a particular agent (equivalent to about 3% of residual drug activity from the initial dose) is frequently used as a means of normalizing a patient’s bleeding risk (2,3). However, the use of laboratory coagulation thresholds is preferable, as half-lives may vary considerably in individual patients due to factors such as the potential presence of drug-drug interactions, idiosyncratic factors, differences in drug metabolism, or genetic influences. Additionally, the exact time point of drug discontinuation may be uncertain or unreliable. Nevertheless, when appropriate laboratory coagulation parameters are unavailable, disproportionally costly, or logistically cumbersome, the use of 5 halflives to normalize bleeding risk can be adequate. In this table formatted document, we summarize some of the current medications and available literature regarding periprocedural coagulation parameter surveillance and medical management of patients undergoing percutaneous image-guided procedures (Tables 1 and 2). Because of the lack of randomized controlled studies or other high-level evidence on this topic, a Delphi panel of experts constructed

Transcatheter Endovascular Techniques for Management of Obstetrical and Gynecologic Emergencies

Since the initial description of selective uterine artery embolization for the treatment of postpartum hemorrhage in 1979, transcatheter embolization and other endovascular techniques have become the second-line therapeutic option for the management of intractable obstetrical and gynecologic bleeding. Advances in catheter-based techniques, as well as recognition of the effectiveness of minimally invasive treatment options, have expanded the role of interventional radiology in the management of hemorrhage for a variety of indications, such as postpartum hemorrhage, menorrhagia, and postmenopausal bleeding. Transcatheter interventions include the following: (1) prophylactic selective catheterization of the internal iliac arteries, with either temporary balloon occlusion or embolotherapy; (2) selective embolization of collateral pelvic vessels in the setting of surgical ligation of the internal iliac arteries and/or delivery-related injuries to the genital tract; (3) transarterial embolization for the management of abnormal placentation; and (4) massive bleeding secondary to uterine leiomyomas (fibroids) and/or arteriovenous malformations. Transcatheter embolization is a fast, safe, and effective minimally invasive alternative to hysterectomy, when medical treatment fails to control uterine bleeding. Moreover, it preserves the uterus with little or no significant impact on future pregnancies and fertility. This article reviews the transcatheter endovascular techniques that are used in a variety of clinical scenarios for the management of obstetrical and gynecologic emergencies.

Acute Limb Ischemia

Acute limb ischemia occurs when there is an abrupt interruption of blood flow to an extremity usually because of either embolic or thrombotic vascular occlusion. When profound ischemia ensues, this represents an emergency in which restoration of perfusion through early intervention can lead to limb salvage, whereas delay may result in significant morbidity, including limb loss and, potentially, death. Patients in whom urgent or semi-urgent surgical or endovascular revascularization is indicated may undergo catheter angiography unless there is a contraindication, such as profound critical limb ischemia, renal dysfunction, or contrast allergy. Alternative imaging modalities include ultrasound, contrast-enhanced computed tomographic angiography, and magnetic resonance angiography. The clinical degree of the ischemic insult will determine the most appropriate course of management, as severely ischemic limbs may require immediate surgical revascularization, while endovascular interventions, such as catheter-directed thrombolysis, may be appropriate in patients with moderate ischemia. Additionally, many percutaneous mechanical thrombectomy devices are being used or undergoing clinical evaluation, either alone or in combination with pharmacologic thrombolysis, for the treatment of acute limb-threatening ischemia. In this article, we present our approach to an acutely ischemic limb, with a focus on the pertinent aspects of endovascular intervention.

Safety and effectiveness of the celect inferior vena cava filter: preliminary results.

PURPOSE To evaluate the safety and effectiveness of the Celect inferior vena cava (IVC) filter during implantation, retrieval, and short-term follow-up. MATERIALS AND METHODS The clinical data of 73 patients (46 men; age range, 22-89 years) who had a Celect IVC filter implanted between August 2007 and June 2008 were reviewed. Twenty-one (28.8%) presented with pulmonary embolism (PE), 15 (20.54%) with deep vein thrombosis (DVT), 12 (16.4%) with both, and the rest (34.26%) with other symptoms. Indications for filter placement were contraindication to anticoagulation (n = 38; 52%), prophylaxis/added protection (n = 22; 30%), failure of anticoagulation (n = 11; 15%), and complications of anticoagulation (n = 2; 3%). Filters were placed in the infrarenal (n = 71) or suprarenal (n = 2) IVC. Follow-up data were reviewed for filter-related complications and recurrent PE. RESULTS All filters were successfully deployed. Immediately after fluoroscopy-guided filter deployment in 61 patients, four filters (6.5%) showed significant tilt. During follow-up (mean, 68 days +/- 73), three patients developed symptoms of PE after filter placement; however, computed tomographic (CT) pulmonary angiography demonstrated new PE in only two. Imaging follow-up with radiography (n = 32), CT (n = 11), and/or angiography (n = 4) in 47 patients (at a mean of 62 days +/- 75) showed no filter migration. Follow-up abdominal CT (at a mean of 69 days +/- 58) was available in 18 patients and demonstrated filter-related problems in seven (39%). These included penetration of filter legs in four and fracture/migration of filter components in one. Fourteen filters were successfully retrieved after a median period of 84 days. CONCLUSIONS The Celect IVC filter can be safely placed but is related to a high incidence of caval filter leg penetration. Symptomatic PE after filter placement confirmed by CT occurred in 2.8% of patients.