IVC Filters: A new era of responsibility

IVC Filters: A new era of responsibility Stephen L. Wang, MD Lead Physician, KP National IVC Filter Registry Director, IVC Filter Clinic KP Santa Clara Vascular/Interventional Radiology

Disclosure of Relevant Financial Relationships Under the ACCME Standards for Commercial Support, everyone who is in a position to control the content of an education activity must disclose all relevant financial relationships with any commercial interest. The participant(s) have disclosed that they have no relevant relationships with commercial or industry organizations. The CME Department has reviewed the disclosure information for this program and has determined that they do not have relationships that present a relevant conflict of interest.

Disclosures I am actively involved in basic science and clinical research on IVC filters. My research is not funded by industry. Suprarenal filter placement is off-label use. No other off- label use is discussed in this presentation.

Objectives 1. Review and understand the current evidence surrounding IVC filters and the FDA advisory on IVC filters. 2. Understand the latest ACCP guidelines for IVC filters and implement them in your practice. 3. Understand the retrieval window for retrievable filters. 4. Describe the importance of IVC filter follow-up and the impact of a dedicated IVC filter clinic.

I. Introduction Overview II. Quick Discussion of PREPIC & population studies III. Trends in Filter Use IV. The FDA Advisory V. Indications Guidelines 2012 VI. Our IVC Filter Clinic Model VII. Filter Tracking Tool VIII. Take Home Points

The Basics/Anatomy SUPRARENAL IVC Rt renal vein Lt renal vein INFRARENAL IVC Rt common Iliac Vein Lt common iliac vein

Filter Location SUPRARENAL IVC FILTER: NOT IDEAL but sometimes necessary Rt renal vein Lt renal vein INFRARENAL IVC FILTER: IDEAL Rt common Iliac Vein Lt common iliac vein

Permanent vs. Retrievable? Permanent IVC filters First Endolumenal device in 1967 Greenfield design in early 1970s Designed for permanent placement Retrievable IVC filters Cook Gunther Tulip available in Europe since 1992 First FDA retrievable indication in 2003 All FDA approved retrievables have permanent indication. Retrieve or remain permanently

Revisiting PREPIC 1. 2 papers, by Decousus et al. France. Benchmark paper. 2. Randomized prospective study 400 pts., n=200 filter + anticoagulation, n= 200 anticoagulation alone. All patients with acute proximal DVT +/- PE. 3. 1 st article: NEJM 1998: 12 day, 3 month, 1 yr, and 2 yr followup 4. 2 nd article: Circulation 2005: 8 yr follow up data

PREPIC Results 1. Rate of PE (Sx & Asx) at 12d: 1.1% filter, 4.8% without filter (p=0.03). Rate at 8yrs: 6.2% filter, 15.1% without. 2. No mortality/survival benefit with filter at 2 yrs or 8 yrs 3. 42% of PE occurred in first year of no filter group 4. 1.5 fold increased risk of DVT with filter (20.8%) vs. no filter (11.6%) at 2 years, p= 0.02. 5. Post thrombotic syndrome rates same (70%)

PREPIC Summary 1. Decrease in PE, BUT 2. No mortality/ survival benefit 3. Increased risk of DVT in long-term with filter 4. But similar rates of post thrombotic syndrome 5. Findings have led to push for retrievable filters to protect acute phase, but remove for thrombotic risk.

Population Studies 1. California discharge data from 1991-1995: 3,600 filter patients, 64,300 control patients, primary Dx VTE 2. Risk adjusted analysis shows no difference in relative hazard (RH) for re-hospitalization for PE among filter and non-filter patients. 3. Filter associated with higher re-hospitalization for venous thrombosis in patients initially hospitalized for PE (RH 2.62, 95% confidence interval 0.92-1.43)

What other resources have concluded on IVC filters: 2010 Cochrane Collaborative 1 : Lack of data and clinical evidence to draw any conclusions or recommendations. 2011 California Technology Assessment Forum (CTAF) 2 A public service forum Review of evidence did not meet criteria for improved health outcomes. Do not recommend IVCF use at all. 1 Young T, Tang H, Hughes R. Vena caval filters for the prevention of pulmonary embolism. Cochrane Database Syst Rev. 2010(2):CD006212. 2 Walsh j. Safety and Effectiveness of Inferior Vena Cava Filters Used to Protect Against Pulmonary Embolus. [PDF] San Francisco: California Technology Assessment Forum; 2011 [cited 2012 April 21];

Trends in IVC filter use 1. Moore, et al. J Vasc Surg 2010 2. 80% increase in filter use 1998-2005 3. 47% increase in patients with known DVT/PE 4. 157% increase in patients without PE/DVT = prophylactic indication Especially with bariatric surgery and head injury. ** OVER 50% of all filter placements nationally placed for prophylactic indications. 5. BUT the VAST majority of filters are never retrieved or followed up. ** Kaufman JA, Rundback JH, Kee ST, Geerts W, Gillespie D, Kahn SR, et al. Development of a research agenda for inferior vena cava filters: proceedings from a multidisciplinary research consensus panel. J Vasc Interv Radiol. 2009 Jun;20(6):697-707.

Inpatient IVC Filter Utilization 140,000 120,000 Inpatient IVC Volume 100,000 80,000 60,000 40,000 2008:>120,000 20,000-2001:60,000 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Year Slide used with permission from Jeremy Friese, MD Leake, CB, Friese, JL, et al. Inpatient Inferior Vena Cava Filter Utilization, Costs, and Outcomes: RSNA 2011.

Geographic Utilization Disparity* IVC filters per normalized discharge date Using data from National Inpatient Sample (2001-2008, n= 8million hospital stays) 0.250% 0.175% 0.335% 0.259% P<0.001* Slide used with permission from Jeremy Friese, MD. Leake, CB, Friese, JL, et al. Inpatient Inferior Vena Cava Filter Utilization, Costs, and Outcomes: RSNA 2011.

Global Utilization Disparity USA population is same as Europe s Big 5 But USA uses 25x as many filters, BUT similar rates of VTE related death annually. European Markets for Clot Management Devices 2012, Millennium Research Group Millennium Research Group, Inc. All rights reserved. Reproduction, distribution, transmission or publication is prohibited. Reprinted with Permission.

FDA Advisory 1. Issued 8/9/2010 2. FDA recommends that implanting physicians and clinicians responsible for the ongoing care of patients with retrievable IVC filters consider removing the filter as soon as protection from PE is no longer needed.

Fractures in Bard G2 and Recovery 1. Followed up 80 pts with Bard Recovery and G2 filters with average dwell time of 50 months for Recovery and 24 months for G2. 2. 25% fracture or fx+ embolization rate based on fluoro +/- CT. 13 patients had Fx, 7 with fx + embo. 3. 5/7 embo cases went to heart: 3 with life threatening V tach or cardiac tamponade, one death. 4. 65,000 Bard G2s placed since 2005 5. FDA advisory issued next day. 6. A recent study corroborates these findings with projected fracture rate up to 40% at 5.5 years with Bard Recovery. (MD Tam et al JVIR 2012) Nicholson et al. Arch Int Med 2010; 170: 1827-1831 Tam et al. J Vasc Interv Radiol 2012; 23: 199-205.

Fractured Bard G2

Fracture/ Embolization Bard G2 Images courtesy G. Vatakencherry, MD

Usoh et al. 2010 J. Vasc Surg 1. Prospective randomized study Greenfield filter vs TrapEase filter. Non industry sponsored. 2. Initial plan to recruit 360 patients, stopped early due to interim findings. N= 156 3. 7% rate of symptomatic IVC/iliac thrombosis in the TrapEase group vs 0% in the Greenfield group (p=0.019). Mean 12 month followup.

IVC Filter Perforation of IVC 1. Filter strut outside the lumen of the IVC into retroperitoneum. 2. Using CT criteria, incidence reported as high as 64 86%.* 3. Vast majority asymptomatic, but not always so. 4. Reports of pancreatitis, bowel perforation, liver injury, aortic injury, and back pain. 5. Degree of perforation appears to progress with dwell time.** *Oh JC et al. Removal of retrievable inferior vena cava filters with CT findings indicating tenting or penetration of the IVC wall. J Vasc Interv Radiol 2011; 22:70-74. **Durack JC et al. Perforation of the IVC: Rule rather than exception after longer indwelling times for the Gunther Tulip and Celect retrievable filters. Cardiovasc Interv Radiol 2012; 35: 299-308.

J Vasc Interv Radiol 2012; 23:1557 1563 Recent Study 2012: n = 620, 120 with follow-up, 38 with CT f/u 86.1% rate of limb penetration For patients with CT follow-up: **24% asx limb penetration to: duodenum, aortic wall or kidney

IVC Filter Perforation Symptomatic Duodenal perforation Incorporated into vertebral body Aortic penetration with pseudoaneurysm* *Image courtesy of Dr. Daniel Putterman, Northshore Hospital

Our IVC Filter Clinic Goals: 1. Educate ordering clinicians on evidence-based ACCP guidelines. Increase rates of filter follow-up. 2. Increase rates of retrieval attempt within 12 weeks window, ideally within 8 weeks.

ACCP Guidelines Important Updates 1. Most commonly cited guidelines from American College of Chest Physicians (ACCP) published in Chest, now in 9 th edition (2012): Grade 1= strong recommendation Grade 2 = weak recommendation Quality of Evidence: A= high, B= moderate, C= low. Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis, 9 th ed.: American College of Chest Physicians Evidence-based clinical practice guidelines. Chest 2012: 141; 7S-47S

ACCP Guidelines: General Indications ACCP Recommends FOR IVC filter use if acute proximal DVT and/or PE AND contraindication to anticoagulation = GRADE 1B Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis, 9 th ed.: American College of Chest Physicians Evidence-based clinical practice guidelines. Chest 2012: 141; 7s-47S

ACCP Guidelines: Anticoagulation in IVC filter patients ACCP Recommends ANTICOAGULATION if patient required IVC filter as an alternative to anticoagulation and bleeding risk has now resolved = GRADE 2B Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis, 9 th ed.: American College of Chest Physicians Evidence-based clinical practice guidelines. Chest 2012: 141; 7s-47S

ACCP Guidelines: Anticoagulation + IVC filter in DVT/PE patients ACCP Recommends AGAINST use of an IVC filter in addition to anticoagulation for patient with acute DVT or PE = GRADE 1B Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis, 9 th ed.: American College of Chest Physicians Evidence-based clinical practice guidelines. Chest 2012: 141; 7s-47S

ACCP Guidelines: Prophylactic pre-op Filters ACCP Recommends AGAINST use of an IVC filter for primary VTE prevention for general and abdominal-pelvic surgery patients = GRADE 2C Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis, 9 th ed.: American College of Chest Physicians Evidence-based clinical practice guidelines. Chest 2012: 141; 7s-47S

Prophylactic IVCF use in Bariatric surgery 1. Nationwide approximately 9% of patients undergoing bariatric surgery received prophylactic IVCFs preoperatively. 2. Many retrospective studies report mixed outcomes 3. Large prospective registry (n= 6,376 with 542 IVCFs) concluded IVCFs do not reduce PE and may lead to additional complications.* We have identified no benefits and significant risks with the use of prophylactic IVCFs in bariatric surgery patients. 4. Systematic review concluded that pending controlled studies, prophylactic IVCF use in bariatric surgery could not be recommended.** *Birkmeyer NJ, Share D, Baser O, Carlin AM, Finks JF, Pesta CM, et al. Preoperative placement of inferior vena cava filters and outcomes after gastric bypass surgery. Ann Surg. 2010 Aug;252(2):313-8. **Rajasekhar A, Crowther M. Inferior vena caval filter insertion prior to bariatric surgery: a systematic review of the literature. J Thromb Haemost. 2010 Jun;8(6):1266-70.

ACCP Guidelines: Prophylactic filters for trauma and SCI patients ACCP Recommends AGAINST use of an IVC filter for primary VTE prevention for major trauma patients (including traumatic brain injury, acute spinal injury, and traumatic spine injury) = GRADE 2C Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis, 9 th ed.: American College of Chest Physicians Evidence-based clinical practice guidelines. Chest 2012: 141; 7s-47S

ACCP Guidelines: Prophylactic filters for orthopedic surgery patients ACCP Recommends AGAINST use of an IVC filter for primary VTE prevention over no thromboprophylaxis for patients undergoing major orthopedic surgery with increased bleeding risk. = GRADE 2C Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis, 9 th ed.: American College of Chest Physicians Evidence-based clinical practice guidelines. Chest 2012: 141; 7s-47S

IVC Filter Clinic Basics EDUCATION is KEY Lectures about filters and evidence-based guidelines given at medicine grand rounds, and to all hospitalists, critical care, and residents. IR has taken ownership of all filters placed at our hospital. All patients have full discussion of risks and benefits of filter placement prior to placement. All patients that have filters placed are entered into our database. Patients return for office consult at 4 weeks to see if they are candidates for retrieval

Pre-IVC Filter Clinic Flow Inpatient/ ICU IVC filter ordered Patients are lost in handoff from inpatient to outpatient medicine and never return to IR IR (IVC FILTER PLACED) ICU/ Stepdown Rehab Facility Home Primary Care MD TIME: 0 weeks 4-6 weeks 6-8 weeks 8-9 weeks 9-12 weeks

Post IVC Filter Clinic Flow Inpatient/ ICU IVC filter ordered Patient is added to IR IVC filter tracking tool after filter is placed. Within 8-9 weeks (12 weeks maximum) candidates for retrieval have retrieval attempt by IR Master list of filter patients generated monthly by controllers office using CPT codes and reviewed by IR. At 4 weeks, patient is assessed for candidacy for retrieval by IVC filter clinic & anticoagulation clinic. ICU/ Stepdown Rehab Facility Home Primary Care MD TIME 0 weeks 4-6 weeks 6-8 weeks 8-9 weeks 9-12 weeks

IVC Filter Clinic Patient Handout

The Tracking Tool

Keys to Retrieval 1. Time is of the essence: For many retrievable filters: best window is <9 weeks**, ideally within 12 weeks.* 2. Most filters are lost in handoff from inpatient to outpatient. (1.2-5.1% retrieval rate in Medicare pop., 2.4% community hospital, and 22% in trauma population)*** *Smouse R, et al. J Vasc Interv Radiol 2009; 20:871-877. **British Society of Interventional Radiology, First UK Inferior Vena Cava Filter Registry Report 2011. *** Duszak R, et al. J Am Coll Radiol 2011; 8: 483-489. Yunus TE et al. J Vasc Surg 2008; 47: 157-165. Karmy-Jones R et al. J Trauma 2007; 62: 17-24.

The Future Critical Questions to be answered: 1. Do IVCFs improve survival in patients who cannot be anticoagulated? 2. Is there a subset of patients for which IVCFs improve survival? Critically ill? Right heart strain? Massive PE? 3. Are retrievable filters safer than permanent filters? 4. Which devices are the safest and most effective?

Take Home Points 1. Educate yourselves on the latest 2012 ACCP guidelines. 2. In our system, implanting IR MDs have taken the lead and responsibility of filter follow-up. 3. Know the data on retrievability of your local filters: <9 weeks ideal, < 12 weeks best chance for most. 4. Have a full discussion with patient prior to placement. Detail risks and possibility of filter remaining permanent.

Acknowledgements Division of Vascular and Interventional Radiology, SCH Francis Bolanos, BSIE: Expertise in programming for our smart sheet tracking tool. Martin Porras, PA-C and Liz Wakley, RN: IR team members who help run our IVC filter clinic and input data. Anticoagulation Clinic: Lawrence Troxell, PharmD; Thuy Cung, PharmD; and Nela Chang, PharmD Controller s Office: Tim Weber and Long Thai Paul Radosevich, MD: Regional IR Chair of Chiefs for regional support. Brian Baker, MD; Mark DuLong, MD; Susan Smarr, MD; Jim Chang, MD for support of our filter clinic model.

END Questions? Feel free to contact me with any questions or comments: Stephen L. Wang, MD email: stephen.l.wang@kp.org