Citation
Vena Cava Filter Retrieval Rates and Factors Associated With Retrieval in a Large US Cohort

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Title:
Vena Cava Filter Retrieval Rates and Factors Associated With Retrieval in a Large US Cohort
Series Title:
J Am Heart Assoc. 2017;6:e006708. DOI: 10.1161/JAHA.117.006708
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Brown, Joshua
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American Heart Association
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English
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Journal Article

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Abstract:
Background-—Retrieval of vena cava filters (VCFs) is important for safety as complications increase with longer dwell times. This study assessed VCF retrieval rates and factors associated with retrieval in a national cohort. Methods and Results-—VCFs were identified by procedural codes from an administrative claims database. Patients were identified who had a VCF placement during a hospitalization from a national commercial administrative claims database. Indications for VCF placement were identified as pulmonary embolism with or without deep vein thrombosis, deep vein thrombosis only, or prophylactic. Patient demographic and clinical characteristics were included in proportional hazard regression models to find associations with early (90-day) and 1-year VCF retrieval. Initiation of anticoagulation and the correlation between time-to-retrieval and time-to-initiation of anticoagulation were observed. Of 54 766 patients receiving a VCF, 36.9% had pulmonary embolism, 43.9% had deep vein thrombosis only, and 19.2% had no apparent venous thromboembolism present. Over the 1 year of follow-up, the cumulative incidence of VCF retrieval was 18.4%. Retrieval increased over time from a low of 14.0% in 2010 up to %24% in 2014. In adjusted time-to-event models, increasing age, differing regions, and some comorbidities were associated with poorer retrieval rates. Initiation of anticoagulation was poorly correlated with retrieval, with anticoagulation preceding retrieval by a median of 51 days while those without retrieval had a median of 278 days of exposure to anticoagulation. Conclusions-—VCF retrieval increased over the study period but remained suboptimal and was weakly correlated with anticoagulation initiation.
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Collected for University of Florida's Institutional Repository by the UFIR Self-Submittal tool. Submitted by Joshua Brown.

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University of Florida Institutional Repository
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University of Florida
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Copyright Creator/Rights holder. Permission granted to University of Florida to digitize and display this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.

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VenaCavaFilterRetrievalRatesandFactorsAssociatedWith RetrievalinaLargeUSCohortJoshuaD.Brown,PharmD,PhD;DrissRaissi,MD;QiongHan,MD,PhD;ValR.Adams,PharmD;JefferyC.Talbert,PhD Background— Retrievalofvenacava lters(VCFs)isimportantforsafetyascomplicationsincreasewithlongerdwelltimes.This studyassessedVCFretrievalratesandfactorsassociatedwithretrievalinanationalcohort. MethodsandResults— VCFswereidenti edbyproceduralcodesfromanadministrativeclaimsdatabase.Patientswereidenti ed whohadaVCFplacementduringahospitalizationfromanationalcommercialadministrativeclaimsdatabase.IndicationsforVCF placementwereidenti edaspulmonaryembolismwithorwithoutdeepveinthrombosis,deepveinthrombosisonly,or prophylactic.Patientdemographicandclinicalcharacteristicswereincludedinproportionalhazardregressionmodelsto nd associationswithearly(90-day)and1-yearVCFretrieval.Initiationofanticoagulationandthecorrelationbetweentime-to-retrieval andtime-to-initiationofanticoagulationwereobserved.Of54766patientsreceivingaVCF,36.9%hadpulmonaryembolism, 43.9%haddeepveinthrombosisonly,and19.2%hadnoapparentvenousthromboembolismpresent.Overthe1yearoffollow-up, thecumulativeincidenceofVCFretrievalwas18.4%.Retrievalincreasedovertimefromalowof14.0%in2010upto 24%in 2014.Inadjustedtime-to-eventmodels,increasingage,differingregions,andsomecomorbiditieswereassociatedwithpoorer retrievalrates.Initiationofanticoagulationwaspoorlycorrelatedwithretrieval,withanticoagulationprecedingretrievalbya medianof51dayswhilethosewithoutretrievalhadamedianof278daysofexposuretoanticoagulation. Conclusions— VCFretrievalincreasedoverthestudyperiodbutremainedsuboptimalandwasweaklycorrelatedwith anticoagulationinitiation. ( JAmHeartAssoc .2017;6:e006708.DOI:10.1161/JAHA.117.006708.) KeyWords: pulmonaryembolism  retrievaldevice  venacava  venacava lter  venousthromboembolism Venacava lters(VCFs)areusedtomechanicallyprevent thrombifrommigratingtothepulmonarycirculation. Generally,VCFsarereservedforpatientswhohaveabsolute orrelativecontraindicationstoanticoagulationandwhoareat ahighriskofrecurrentvenousthromboembolism(VTE).1 – 3WiththeadventofretrievableVCFs,therehasbeenamarked increaseinoveralluse.4 – 6RetrievableVCFsdifferinthatthey canberemovedoncecontraindicationshavesubsidedand patientscanbeinitiatedonanticoagulation. Inreal-worldsettings,retrievalratesofVCFshavebeen dismal,withreportsrangingfrom10%to50%andanestimated averagenear30%.7,8Poorretrievalratescorrespondtoan increaseinreportedadverseevents.7ComplicationsassociatedwithVCFsincludeincreasedriskofdeepveinthrombosis (DVT),inferiorvenacavathrombosis,inferiorvenacava penetration,VCFfracture,andVCFembolization.7,9 – 11Given thesetrends,theUSFoodandDrugAdministrationhasissueda safetycommunicationhighlightingtheneedtoremoveVCFs oncetheriskofpulmonaryembolism(PE)hassubsidedbased onmodelingstudiesshowingthatVCFsaremostclinically bene cialifretrievedwithin90daysafterimplantation.11,12GiventhecontinuedgrowthinVCFuseandthevariation thathasbeenobservedbetweeninstitutions,13 – 17assessmentofwhatfactorsdriveretrievalratesandtimingof anticoagulationonanationalscaleisneededtoevaluate clinicalpractice.18Thisstudysoughttoevaluatethetrendin retrievalratesandpatientfactorsassociatedwithretrievalas wellastheassociationbetweenretrievalandanticoagulation. Whileretrievalrateswereexpectedtoincreaseovertime,we hypothesizeddifferentialretrievalbasedonindicationand patientcharacteristics.Furthermore,wehypothesizedthere wouldbeaweakassociationbetweenretrievalandanticoagulation,althoughtreatmentwithanticoagulationgenerally indicatestherewouldnolongerbeacontinuedneedforan indwellingVCF. FromtheDepartmentofPharmacyPracticeandScience,UniversityofKentucky CollegeofPharmacy,Lexington,KY(J.D.B.,V.R.A.,J.C.T.);Departmentof PharmaceuticalOutcomesandPolicy,UniversityofFloridaCollegeof Pharmacy,Gainesville,FL(J.D.B.);DivisionofVascularandInterventional Radiology,DepartmentofRadiology,UniversityofKentuckyCollegeof Medicine,Lexington,KY(D.R.,Q.H.). Correspondenceto: JoshuaD.Brown,PharmD,PhD,1225CenterDr,HPNP Room3320,Gainesville,FL.E-mail:joshua.brown@u .edu ReceivedMay20,2017;acceptedAugust1,2017. 2017TheAuthors.PublishedonbehalfoftheAmericanHeartAssociation, Inc.,byWiley.ThisisanopenaccessarticleunderthetermsoftheCreative CommonsAttribution-NonCommercial-NoDerivsLicense,whichpermitsuse anddistributioninanymedium,providedtheoriginalworkisproperlycited, theuseisnon-commercialandnomodi cationsoradaptationsaremade. DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation1 ORIGINALRESEARCH

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MethodsDataSourceThisobservationalcohortstudyutilizedtheTruvenHealth AnalyticsMarketScandatabase,whichareadministrative healthcareclaimsdataincludingmedicaldiagnosticand proceduralinformationandpharmacy llrecordsbilledtoan individual ’ shealthinsurance.Thedataincludeinformationfor 40millionuniqueindividualsperyear.Theuniversity ’ s InstitutionalReviewBoardapproveduseofthedataand waivedtherequirementforinformedconsentofparticipants giventhatthedataarede-identi edandcollectedfor nonresearchpurposes.CohortIdenti cationAllpatientsduringtheyears2010to2014whohadaVCF placedwereidenti edusing CurrentProceduralTerminology (CPT:37191,37620,35940)and InternationalClassi cation ofDiseases,9threvision (ICD-9:38.7)proceduralcodes.The indicationforVCFwasidenti edbyICD-9diagnosiscodesas PE(415.1x)withorwithoutDVT,DVTonly(451.xxor453.xx), ornoapparentVTE(prophylactic).19,20Toincreasethevalidity oftheseindicationdiagnoses,onlytheprimarydiagnosis eld wasused.Forinclusion,patientswererequiredtobe18years oldorolderandhaveaminimumof6monthsofeligibilityin thedatabasebeforeVCFplacement.CohortCharacteristicsDemographicvariablesincludedage,sex,geographicregion, andresidencestatus.Agewasdividedinto18to34,35to44, 45to54,55to64,65to74,and75andoldercategories. GeographicregionincludedUScensusregions(Northeast, NorthCentral,South,West,andunknown)andresidence statuswasdividedintourbanorrural.Insurancestatuswas classi edascommercialorMedicare,fullyorpartially capitated,andassignmenttoaprimarycareprovider(PCP). ConditionsandprocedurespresentduringVCFimplantationwererecorded.Concurrentbleeding,unstablecondition, sepsisorsepticshock,infection,anemia,trauma,and pregnancywereallrecordedusingICD-9diagnosiscodes.13,20Patientsreceivingthrombolytictherapy,embolectomyprocedures,ormajorsurgerywereidenti edusingacombinationof proceduralcodes.21PatientswhodiedduringthehospitalizationduringwhichtheVCFwasplacedwerealsonoted. Comorbidconditionsobservedinthepre-indexperiod consistedofCharlsoncomorbiditiesalongwithaCharlson ComorbidityIndex,whichrepresentstheoverall “ comorbidity burden ” widelyusedforriskadjustment.22,23OutcomeEventsTheprimaryoutcomewasVCFretrievalidenti edbyCPT (37193,37203)andICD-9(38.7)procedurecodes.Given thattheICD-9procedurecodeforplacementandretrievalis thesame,retrievalsforthosepatientsonlyhavingtheICD-9 procedurecodepresenthadtobeonseparatedaystorecord retrieval.However,sinceCPTcodesandnotICD-9codesare usedforbillingpurposes,patientslackingtheCPTcodeswere theexception,with > 95%ofallpatientshavingCPTcodes recorded.PatientswerefollowedforwardfromtheVCF placementuntiltheVCFwasretrieved,theydied,theywere losttofollow-up,ortheendofthestudyperiod.The30-,60-, 90-,180-day,and1-yearcumulativeincidenceofVCFretrieval wasestimatedusingFineandGray ’ stime-to-event,survival analysismethodology,accountingfordeathasacompeting risk.24TimetoVCFretrievalwasalsoreported.TimetoAnticoagulationInitiationAnticoagulationinitiationwasassessedasthe rstoutpatient prescriptionforaninjectable(dalteparin,enoxaparin, ClinicalPerspectiveWhatIsNew? Thisisthe rstknownstudytoexamineretrievalratesfor venacava lters(VCFs)inanationalcohort.  Theresultsareconsistentwithpriormeta-analysesofsingle institutionretrievalratesshowingabouta25%to30% retrievalrateofallplaced.  DespitesafetywarningsforindwellingVCFs,mostremained inplaceandwerepoorlycorrelatedwithinitiationof anticoagulation.  Retrievalrateswerestronglydependentonage,witholder patientslesslikelytohaveretrieval,patientresidence, prophylacticindicationforVCFplacement(nothrombosis present),andhavingVCFplacementinmorerecentyears.WhatAretheClinicalImplications? TheUSFoodandDrugAdministrationhassuggestedthat VCFsberemovedonceclinicallyappropriatetoavoid complications.  ThesewarningswereinresponsetomanyreportsofVCF failuresincludingdevicefracturesandpenetrationofthe venacavathatwereassociatedwithindwelltime.  Inordertomaximizethenetclinicalbene tofVCFs, patientsshouldbeinitiatedonanticoagulationonce contraindicationshaveabatedandVCFsshouldberemoved.  UtilizationofVCFsandsubsequentretrievalratesvary widelybygeography,suggestingthatinstitutionsandclinics shouldevaluatetheirpracticestobetterensurepatient safety. DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation2 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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tinzaparin,fondaparinux)ororal(warfarin,dabigatran,rivaroxaban,apixaban)anticoagulant.Thosewithprophylacticindications( “ noVTE ” )wereexcludedastheymightnothave indicationsforanticoagulationondischarge.Furthermore, thosewhohadVCFretrievalbeforedischargewereexcluded. Timetoanticoagulationwascomparedwiththetimeto retrievalanddescribedforthosewhodidnothaveretrieval duringfollow-up.Timeforbotheventswascalculatedbased onthedateofdischargefromahospitalizationsincethe lled prescriptionsdatawouldnotbeavailableuntilhospital dischargeoccurred.Time-to-EventAnalysisToidentifyfactorsassociatedwithVCFretrieval,wedevelopedaCoxproportionalhazardsmodelincludingpatient characteristics.TheproportionalityassumptionforallvariableswasevaluatedforusingSchoenfeldresidualsaswellas usingtimeasaninteractiontermforeachvariable.Both methodsshowedthatthisassumptionheldtrue.Becauseof collinearitywithage,Medicareorcommercialinsurance statuswasexcludedinthemodel.Twomodelswere estimatedpredicting90-dayand1-yearretrieval.The90-day timepointwaschosentorepresent “ earlyretrievals ” andwas consistentwithapriormodelingstudyshowinghighernet clinicalbene tifremovedin < 90days.11Patientswhohad nothadretrievalorhadnotdiedattheendofthe90-dayor 365-dayperiodwerecensored.Hazardratiosandtheir95% con denceintervalswereestimated.Allanalyseswere conductedusingSASEnterpriseGuideversion7.1(Cary, NC)withsigni cancelevelof a = 0.05forallstatistical analyses.ResultsPatientCharacteristicsDuring2010to2014,54766patientsreceivedaVCFand mettheeligibilityrequirementstobeincludedinthestudy.Of these,36.9%presentedwithaPE,43.9%withDVTalone,and 19.2%hadnoapparentVTEpresent(Table1).Themean(SD) ageofthecohortwas65(16)yearsold,51%werefemale,and theyweregeographicallydiversewithnearly85%residingin urbanareas.Insurancedetailsincluded13.9%ofthecohort havingaprimarycareproviderand8.6%havinginsurancewith fullorpartialcapitatedpayments.Atotalof1628(3.0%)of thecohortdiedduringtheinitialhospitalizationandwerenot includedinsubsequentanalyses. Overall,14.3%(N = 7619)ofthecohortwhosurvivedthe indexhospitalizationhadtheVCFretrievedwithin1year and8%(N = 4228)died(Table2).Forthosewhohad retrieval,themean(SD)timetoretrievalwas93(78)days, withamedianof71daysandinterquartilerange(IQR)of 35to130days.ThosewithPEhadthehighestmeanand mediantimestoretrieval(101and81days)comparedwith thosewithDVTonly(91and68days)andcomparedwith thosewithnoVTE(83and61days, P < 0.001forall comparisons). Figure1showsthecumulativeincidenceofVCFretrieval bytheindexindicationandTable3showsthecumulative incidenceforselectedvariables.At1year,retrievalwas highestforthosewithnoVTEonindex,reachingnearly 25%(23.9 – 25.8%).Retrievalincreasedwitheachyearof study,goingfrom14.0%(13.3 – 14.7%)in2010upto38.2% (19.4 – 57.0%,skewedbylowfollow-uptime)in2014 ( P < 0.001fortrendexcluding2014data).Datafrom2014 allowedforsmallersamplesizefor1-yearoffollow-up. However,trendswereconsistentacrosssmallertime framesfor2014andshowedayear-over-yearincreasein retrievalatalltimepoints.Differencesinretrievalbetween agegroupsweresigni cant,withyoungeragegroups havinghigherretrieval.Forexample,thoseaged18to34 had1-yearretrievalof42.8%(40.4 – 45.2%)whileretrievalin those75yearsoldandolderwasjust5.4%(5.0 – 5.8%, P < 0.001).FactorsRelatedtoRetrievalInfullyadjustedanalyses(Table4),ageremainedsigni cantlyassociatedwithVCFretrievalatboth90daysand 365daysoffollow-up,althoughtheassociationwasmuch strongerforthe1-yearmodel.PatientswithnoVTEwere morelikelytohaveretrievalcomparedwiththosewithDVT only,andtherewasnodifferenceinretrievalbetween thosewithPEcomparedwiththosewithDVT.Geographic regionwasalsosigni cant,withthoseresidingintheNorth Central(90daysand1year)andWest(1yearonly)regions beingmorelikelytohaveretrievalcomparedwiththosein theNortheast. Yearof lterplacementwasmodeledbothasacovariate aswellasusedtostratifytheanalysis.Instrati edanalysis, nodifferenceswereobservedbetweenthecovariatesand theirassociationwithVCFretrievalcomparedwiththebase modelwithyearasacovariate.Asacovariate,eachyearof VCFplacementwasassociatedwithincreased90-dayand 1-yearretrievalcomparedwithyear2010.Forthe nalyear 2014,thiscorrespondedtonearlya2-folddifferencein retrievalratecomparedwith2010(hazardratio = 1.90,95% con denceinterval,1.76 – 2.06).TimetoAnticoagulationDuringfollow-up,thedatasethadfollow-upprescription informationfor37272personsinthecohortwithDVT/PE DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation3 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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Table1. DemographicandClinicalCharacteristicsofPatientsReceivingVCFsbyIndicationAllPulmonaryEmbolismDeepVeinThrombosisNoPE/DVT N%N%N%N%54766100.02020236.92406043.91050419.2 Agegroup(y) Mean,SD65(16)64(15)69(16)60(17) 18to3421964.07283.66102.58588.2 35to4435516.513476.711834.910219.7 45to54788814.4333716.5275711.5179417.1 55to641307623.9553027.4488120.3266525.4 65to74942217.2345217.1433418.0163615.6 75andolder1784632.6549227.21003841.7231622.0 Sexofpatient Male2683949.01021750.61154248.0508048.4 Female2792751.0998549.41251852.0542451.6 Region Northeast1152621.0415420.6519121.6218120.8 NorthCentral1567828.6575228.5714229.7278426.5 South1844833.7666633.0788232.8390037.1 West789114.4315815.6336114.0137213.1 Unknown12232.24722.34842.02672.5 Residence Rural849615.5311915.4338114.1199619.0 Urban4627084.51708384.62067985.9850881.0 Concurrentconditionsduringhospitalization Bleed50049.114187.0277911.68077.7 Unstablecondition8701.62431.24641.91631.6 Sepsis23514.36193.113605.73723.5 Infection920216.8310515.4468019.5141713.5 Anemia1019518.6319315.8543322.6156914.9 Trauma577710.516007.9302712.6115010.9 Thrombolytictherapy8411.54522.23161.3730.7 Embolectomyprocedure3670.71760.91490.6420.4 Majorsurgery1337124.4524926.0583624.3228621.8 Pregnant4410.81480.72210.9720.7 Diedduringhospitalization16283.07203.64611.94474.3 Comorbidconditions CCIscore,mean(SD)3.1(3.3)2.9(3.3)3.5(3.4)2.9(3.3) HistoryofVTE48648.915227.521498.9119311.4 Historyofbleeding848315.5258712.8457719.0131912.6 MI32545.911225.616236.75094.8 CHF846415.5262013.0451418.8133012.7 PVD745013.6214710.6403016.7127312.1 Dementia23664.36213.115186.32272.2Continued DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation4 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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indicationsandwhodidnothaveretrievalbeforedischarge. Amongthese,23510(63.1%)initiatedanticoagulation including61%whoneverhadretrieval,79.2%amongthose withretrieval,and47.8%amongthosewhodied,with mediantimetoinitiationof17(IQR6 – 50)days.Initiation ofanticoagulationdifferedsigni cantlyforthosewho eventuallyhadretrieval(N = 4729,median11,IQR5 – 31days)andthosewhodidnothaveretrieval(N = 17628, median17,IQR6 – 50days, P < 0.001).Overall,timeto anticoagulationandtimetoretrievalwerepoorlycorrelated, withanticoagulationprecedingretrievalbyamedianof51 (IQR13 – 110)daysand R2= 0.06(Figure2).Forthosewho neverhadretrieval,therewasamedianof278(IQR98 – 350)daysofanticoagulationtreatmentduringthe1-year follow-upperiod.DiscussionInPREPIC2(PreventionduRisqued ’ EmboliePulmonairepar InterruptionCave2),theonlyrandomizedtrialforretrievable VCFs,theretrievalratewas > 90%withadedicated3-month follow-upvisit.25However,inreal-worldpractice,estimatesof theretrievalratesrangemuchlower,withanaverageofabout onethirdofallVCFseventuallybeingretrieved.7Patientsare atriskforcomplicationsincludinginferiorvenacavathrombosis,devicefracture,devicemigration,andDVTsolongas Table1. ContinuedAllPulmonaryEmbolismDeepVeinThrombosisNoPE/DVT N%N%N%N% COPD1292523.6487224.1573523.8231822.1 Rheumatism22864.28014.010874.53983.8 PUD15932.95032.58293.42612.5 Mildliverdisease43447.915867.919588.18007.6 Severeliverdisease5491.01350.73151.3990.9 Diabetesmellitus1362324.9448322.2632226.3281826.8 Diabetesmellitusw/complications36636.710405.118537.77707.3 Paralysis22444.16723.312285.13443.3 Renaldisease668412.217138.5383615.9113510.8 Cancer1667230.4625130.9785632.7256524.4 Metastaticcancer753413.8301314.9343314.3108810.4 Stroke974417.8295714.6524021.8154714.7 Hypertension3091856.51071953.11454160.4565853.9 CHD1112520.3360417.8559723.3192418.3 Hyperlipidemia1819533.2667633.0804733.4347233.1 Insurancesource Commercial2635048.11082153.6928138.6624859.5 Medicare2841651.9938146.41477961.4425640.5 Insurancedetails Assignedcareprovider758613.9291014.4311613.0156014.9 Capitatedpayment47188.618219.019698.29288.8 YearVCFplaced 20101178421.5425021.0523921.8229521.8 20111275023.3456522.6567223.6251323.9 20121221022.3436921.6539322.4244823.3 2013939517.2359617.8406216.9173716.5 2014862715.8342216.9369415.4151114.4CCIindicatesCharlsonComorbidityIndex;CHD,coronaryheartdisease;CHF,congestiveheartfailure;COPD,chronicobstructivepulmonarydiseas e;DVT,deepveinthrombosis;IVC, inferiorvenacava;MI,myocardialinfarction;PE,pulmonaryembolism;PUD,pepticulcerdisease;PVD,peripheralvasculardisease;VCF,venacava lter;VTE,venousthromboembolism DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation5 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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theVCFremainsinplace.7,26Onestudyfoundthatthereisan optimalnetclinicalbene tifaVCFisretrievedwithin29to 54daysafterplacementinprophylacticindications,which remainedinfavorofVCFsupto180dayspostimplantation.11ThatarticlewasreferencedbyaUSFoodandDrug Administrationsafetycommunication,whichrespondedto multiplereportsofcomplicationswithVCFsandincreasing publicitythroughlitigationandmedia.12Thecurrentanalysisisconsistentwithotherreports regardingVCFretrieval.7,8Theretrievalrateincreasedover time,fromroughlyevery1-out-7VCFsbeingretrievedin2010 upto1-out-4retrievedin2014.Thiseffectmaybeexplained bytheincreasedattentionVCFsreceivedoverthistimeperiod includingUSFoodandDrugAdministrationsafetyalerts,as wellasguidelineupdates(AmericanCollegeofChest Physicians),1whichcalledformoreconservativeuseofVCFs Table2. OutcomesofPatientsReceivingVCFsAt1YearofFollow-UpOverallPEDVTNoVTEOutcome VCFretrieval7619(14.3%)2884(14.8%)2686(11.4%)2049(20.4%) Died4228(8.0%)1627(8.4%)1950(8.3%)651(6.5%) Censored41291(77.7%)14971(76.8%)18963(80.4%)7357(73.2%) Follow-uptime Mean,SD202(144)202(143)202(145)200(144) Median,IQR186(56 – 365)188(58 – 365)187(54 – 365)176(56 – 365) Timetoretrieval Mean,SD93(78)101(81)91(79)83(73) Median,IQR71(35 – 130)81(38 – 143)68(33 – 132)61(32 – 113) Timetodeath Mean,SD96(91)94(91)97(91)100(90) Median,IQR63(26 – 142)58(24 – 140)66(26 – 144)67(32 – 141)DVTindicatesdeepveinthrombosis;IQR,interquartilerange;PE,pulmonaryembolism;VCF,venacava lter;VTE,venousthromboembolism. Figure1.Cumulativeincidenceofvenacava lter(VCF)retrievalbyindicationover1-yoffollow-up accountingfordeathasacompetingrisk.VTEindicatesvenousthromboembolism. DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation6 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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comparedwithguidelinespresentedbyotherphysician societiesininterventionalradiologyandtrauma.27,28For thosewhodidhavetheirVCFretrievedinourstudy,timeto retrievalwaswithinmeanandmediantimesof93and71 dayspostimplantation.However,retrievalwaspoorlycorrelatedwithanticoagulationinitiation. Severalpatient-relatedfactorswerealsoassociatedwith retrieval,includingdemographicandclinicalcharacteristics. Increasingageofthepatientwasassociatedwithlower retrieval,whichlikelycontributedtoperceivedongoingriskof PEoradesiretonottreatolderindividualswithanticoagulation.Regionofresidencewasalsostronglyassociatedwith retrieval,whichmayindicateregionalpracticedifferencesas wellasdifferencesinpatientdemography.Patientslivinginan urbansettingweremorelikelytohavetheir lterretrievedas well,suggestingthatpatientsbeingreferredtoadistant medicalcenterforVCFplacementmayhavelimitedfollow-up forretrieval.Amongpatientcomorbidities,thoseconsidered prothrombotic(eg,cancer,stroke,hyperlipidemia,myocardial infarction)andrelatedtobleeding(eg,liverdisease)were associatedwithlowerretrieval. Otherstudiesinvestigatingfactorsassociatedwithretrieval rateshavefocusedonpoorpatientfollow-upastheprimary reasonVCFsarenotremoved.29 – 33Patientfollow-upis generallylefttothereferringorprimaryphysician,withsome studiesshowingimprovedretrievaliftheresponsibilityof follow-upisplacedontheimplantingphysicianinstead.32 – 34In institutionswheretheimplantingphysiciansaremaderesponsibleforpatientfollow-up,retrievalrateshaveincreasedfrom 24%to59%and29%to60%.32,33Whilethereisinherentconcernforpatientsafetyassociatedwiththeselowretrievalrates,clinicalpracticesarealso nanciallyincentivizedtoincreaseretrievalofVCFs.One studyshowedthatbecauseoftheincreasedcostbetween Table3. CumulativeIncidenceand95%Con denceIntervalofInferiorVCFRetrievalatTimeIntervalsbyKeyDemographicand ClinicalFactors30Days60Days90Days180Days365daysOverall,%3.3(3.1 – 3.5)6.9(6.7 – 7.2)9.8(9.5 – 10.1)14.9(14.6 – 15.2)18.4(18.0 – 18.8) Indication NoVTE,%5.2(4.7 – 5.6)11.0(10.4 – 11.7)15.0(14.3 – 15.8)21.3(20.4 – 22.2)24.8(23.9 – 25.8) DVT,%2.8(2.6 – 3.0)5.8(5.5 – 6.1)7.9(7.5 – 8.2)12.1(11.6 – 12.6)14.9(14.3 – 15.4) PE,%2.9(2.7 – 3.1)6.1(5.8 – 6.5)9.3(8.9 – 9.8)14.8(14.3 – 15.4)19.2(18.5 – 19.8) YearVCFplaced 2010,%3.1(2.8 – 3.5)6.0(5.6 – 6.5)8.0(7.5 – 8.6)11.3(10.7 – 11.9)14.0(13.3 – 14.7) 2011,%3.0(2.7 – 3.3)6.3(5.9 – 6.8)8.8(8.3 – 9.3)13.2(12.6 – 13.9)16.1(15.4 – 16.8) 2012,%3.4(3.1 – 3.8)7.5(7.0 – 8.0)9.9(9.4 – 10.5)15.6(14.9 – 16.3)19.2(18.4 – 20.0) 2013,%3.3(3.0 – 3.7)7.5(7.0 – 8.1)11.2(10.5 – 11.9)17.1(16.3 – 18.0)21.6(20.7 – 22.6) 2014,%3.7(3.3 – 4.2)7.7(7.1 – 8.3)12.4(11.6 – 13.3)20.5(19.4 – 21.6)38.2(19.4 – 57.0)*Agegroup(y) 18to34,%6.8(5.8 – 7.9)15.2(13.7 – 16.8)22.8(21.0 – 24.7)34.9(32.7 – 37.1)42.8(40.4 – 45.2) 35to44,%6.1(5.3 – 6.9)13.9(12.7 – 15.1)18.9(17.6 – 20.3)28.4(26.8 – 30.0)35.5(33.7 – 37.2) 45to54,%4.9(4.5 – 5.5)11.4(10.7 – 12.2)15.9(15.0 – 16.8)23.7(22.6 – 24.7)29.3(28.1 – 30.4) 55to64,%3.9(3.5 – 4.2)8.0(7.5 – 8.5)11.5(10.9 – 12.1)17.8(17.0 – 18.5)21.8(21.0 – 22.7) 65to74,%2.7(2.4 – 3.1)5.3(4.8 – 5.8)7.4(6.9 – 8.0)11.4(10.7 – 12.1)14.1(13.3 – 15.0) 75andolder,%1.4(1.2 – 1.6)2.4(2.1 – 2.6)3.1(2.8 – 3.3)4.5(4.1 – 4.8)5.4(5.0 – 5.8) Cancer Yes,%2.6(2.3 – 2.8)4.5(4.2 – 4.9)6.3(5.9 – 6.7)9.1(8.6 – 9.7)11.7(11.1 – 12.4) No,%3.6(3.4 – 3.8)7.9(7.6 – 8.2)11.1(10.8 – 11.5)17.0(16.6 – 17.5)20.8(20.4 – 21.3) Insurancesource Commercial,%4.8(4.5 – 5.0)10.5(10.1 – 10.9)14.9(14.5 – 15.4)22.6(22.1 – 23.2)28.0(27.4 –28.6) Medicare,%1.9(1.7 – 2.0)3.4(3.2 – 3.6)4.6(4.3 – 4.9)7.0(6.6 – 7.3)8.6(8.2 – 8.9)DVTindicatesdeepveinthrombosis;VCF,venacava lter;PE,pulmonaryembolism;VTE,venousthromboembolism. *Estimatesforlong-termfollow-upin2014areunstablebecauseofsmallersamplesizes.Extrapolationof20146-monthestimateswiththeoveralltr endinretrievalratesacross2010to 2014producearetrievalestimateof23%to25%. DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation7 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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Table4. RegressionResultsShowingPatientFactorsAssociatedWith90-D(Early)Retrievaland1-YearRetrieval90-DRetrieval1-YRetrieval HR95%CIHR95%CIAgegroup(y) 18to34Ref.Ref.Ref.Ref.Ref.Ref. 35to440.970.941.000.880.800.97 45to540.950.920.980.790.720.86 55to640.910.880.930.620.570.68 65to740.870.840.890.410.370.45 75andolder0.820.800.840.170.150.19 Sex MaleRef.Ref.Ref.Ref.Ref.Ref. Female1.011.011.021.040.991.09 Region NortheastRef.Ref.Ref.Ref.Ref.Ref. NorthCentral1.031.021.041.291.201.38 South0.990.981.000.890.830.95 West1.101.091.121.891.762.04 Unknown1.010.981.041.241.051.46 Residence RuralRef.Ref.Ref.Ref.Ref.Ref. Urban1.011.001.021.131.061.21 IndexVTE DVTonlyRef.Ref.Ref.Ref.Ref.Ref. NoVTE1.051.031.061.241.171.32 PE0.990.981.000.990.931.04 Concurrentconditionsduringhospitalization Bleed1.000.991.021.100.931.29 Unstablecondition0.980.961.000.800.601.06 Sepsis1.000.981.010.920.761.12 Infection0.980.970.990.840.760.91 Anemia0.990.980.990.910.840.98 Trauma0.990.981.001.000.921.09 Thrombolytictherapy1.061.021.091.291.111.49 Embolectomyprocedure1.000.961.040.890.681.17 Majorsurgery0.980.970.990.920.870.97 Pregnant1.050.991.111.361.151.60 Comorbidconditionsduringpre-indexlookback CCIscore(per1unit)1.000.991.010.970.901.05 HistoryofVTE1.031.021.041.171.081.26 Historyofbleeding0.980.970.990.770.670.87 Myocardialinfarction0.990.981.000.820.710.96 Heartfailure0.980.970.990.670.600.74 Peripheralvasculardisease0.990.981.000.850.770.94Continued DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation8 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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retrievableandpermanentdevices,retrievabledevicesare onlycost-effectiveininterventionalradiologyclinicsifatleast 40%areeventuallyretrieved,drivenbyseparatebillable procedurecodesforimplantationandretrieval.34Even withoutthecostdifferentialbetweenpermanentandretrievabledevices,itisinherentthatclinicrevenuewillbeincreased withimprovedpatientfollow-up,management,andretrieval. Atleast1studyatasingleinstitutionevaluatedthe nancial feasibilityofimplementingaqualityimprovementinitiative withintheirclinicalpractice.35Theycomparedbaseline retrievalrateswiththoseachievedbyissuinglettersto patientsandthenwiththoseachievedwithprospective follow-upofpatients.Overall,theirretrievalratesincreased from8%to40%withmailedletterstoretrospectivepatients, andincreasedfurtherupto52%withprospectivefollow-upof newpatients.AlthoughimprovingVCFretrievalrequiresa shiftinpatientmanagement,retrievalwillimprovepatient outcomesandprovides nancialincentivetotheclinic.LimitationsThisstudyhaslimitationsinherenttoallstudiesutilizing administrativeclaimsdata.36,37Mostnotably,detailedclinicaldataarenotavailable,whichmayhaveimpactedthe studyresults.ProceduralcodeswereutilizedtoidentifyVCF placement;however,thesecodesarenotspeci cto permanentorretrievabledevices.Asof2006,retrievable devicesmadeupabout85%oftheVCFmarketintheUnited States,whichlikelyincreasedto > 90%sincethen.38 – 41Therefore,theretrievalestimatespresentedhereareunderestimated.Assumingthat10%to20%ofallVCFsusedare permanentandthuscannotberetrieved,thiswouldmake Table4. Continued90-DRetrieval1-YRetrieval HR95%CIHR95%CI Dementia0.970.960.980.310.220.43 COPD0.990.981.000.880.830.94 Rheumatism1.000.981.010.960.841.08 Pepticulcerdisease1.021.001.041.160.951.41 Mildliverdisease1.000.981.011.000.911.11 Severeliverdisease0.990.981.000.860.810.92 Diabetesmellitus0.990.981.000.960.851.09 Diabetesmellitusw/complications0.980.971.000.760.650.89 Paralysis0.980.970.990.810.730.90 Renaldisease0.990.981.000.940.871.00 Cancer0.910.890.940.280.170.46 Metastaticcancer0.920.900.930.430.380.49 Stroke0.980.980.990.800.730.88 Hypertension1.000.991.000.950.900.99 Coronaryheartdisease1.000.991.000.870.800.94 Hyperlipidemia1.021.011.031.231.171.30 Insurancedetails Assignedcareprovider1.000.991.021.030.941.12 Capitatedpayment0.990.971.000.840.750.94 YearVCFplaced 2010Ref.Ref.Ref.Ref.Ref.Ref. 20111.011.001.021.191.111.28 20121.031.021.041.411.321.52 20131.041.031.051.631.511.75 20141.051.041.071.901.762.06C-indexformodels:90-dretrieval(0.695),1-yretrieval(0.720).CCIindicatesCharlsonComorbidityIndex;CI,con denceinterval;COPD,chronicobstructivepulmonarydisease;DVT,deep veinthrombosis;HR,hazardratio;PE,pulmonaryembolism;VTE,venousthromboembolism. DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation9 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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ourestimatedretrieval 26%to30%,makingthiscorrected estimatenearpreviousestimatesofnationalretrievalrates of 30%.6,7Weallowedenrollmentofpatientsin2014,butthose enrolledlaterin2014wouldhavelimitedfollow-up,which skewedtheestimatesofcumulativeretrievalat365days. However,theincreasingtrendinretrievalratesisstable acrossestimatesatearliertimepoints(30,60,90,and 180days)in2014.Extrapolatingthesestableestimatesfrom 180daysto365daysacrossallyearsshowsatrend increasingyear-to-yearof + 2%to4%.Therefore,wehave estimatedthatwithperfectfollow-upforthoseenrolledin 2014,theretrievalestimatewouldbenearer23%to25%. Itisunclearhowselectionofretrievableversuspermanent deviceswoulddifferbetween,forexample,olderversus youngerpatientsorincancerpatientswithpoorprognosis, addingsomeuncertaintytothecomparisonofretrieval betweencertainrelevantgroups.However,incontemporary patients,useofretrievableVCFs(alsoreferredtoas “ optional ” VCFsbecausetheycanbeleftpermanentlyor retrievedwhenclinicallyindicated)maybeamorepreferred therapeuticoptionallowingfor exibilityincareversus nonretrievablealternatives.Thus,whiletheremaybea differentialin uenceofthislimitation,theresultsarestill interpretabletoidentifypatientsubgroupsthatarelesslikely toreceive,aswellastonothaveretrievalof,retrievableVCFs. Therefore,thetrendshowinganincreaseinretrievalrates likelyindicatesbothatrendinuptakeofretrievableVCFsas wellasincreasedretrievalrates.Moreworkwillbeneeded withdetailedclinicaldatatodeterminedifferencesin selectionofpermanentversusretrievabletreatmentoptions. Lastly,routinemedicationsadministeredduringahospital stayareoftenomittedfrombillingrecordsbecauseof capitatedpaymentsystems.Thus,wedidnotattemptto observeuseofanticoagulationduringthehospitalstay becauseitwouldbeunreliablyreportedorunreported.ConclusionInthisnationalstudyofVCFretrieval,lessthan1ofevery4 lterswasretrievedwithin1year.Retrievalratesdifferbased onpatientcharacteristicsbutincreasedoverthestudytime period(2010 – 2014),whileretrievalandinitiationofanticoagulationwerepoorlycorrelated.Physiciansshouldconsider ongoingindicationsforindwellingVCFsandtimingofretrieval withanticoagulationinitiationthroughoutfollow-uptooptimizepatientcare.SourcesofFundingTheprojectdescribedwassupportedbytheNationalCenter forAdvancingTranslationalSciences,NationalInstitutesof Health,throughgrantnumberUL1TR000117.Thecontentis solelytheresponsibilityoftheauthorsanddoesnotnecessarilyrepresenttheof cialviewsoftheNIH.Drs.Brownand Figure2.Plotoftimestooutpatientanticoagulationandvenacava lterretrieval.Blacklinerepresents the tofthedata.Timeisbasedonfollow-upafterthedischargedatefromthehospitalizationwherethe VCFwasplaced.Thosewithprophylacticindicationsandthosewithretrievalbeforedischargeareexcluded. R2= 0.06.VCFindicatesvenacava lter. DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation10 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH

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Adamsweresupportedbyaresearchgrantfromthe Hematology/OncologyPharmacistsAssociation.DisclosuresNone.References1.KearonC,AklEA,OrnelasJ,BlaivasA,JimenezD,BounameauxH,HuismanM, KingCS,MorrisTA,SoodN.AntithromboticTherapyforVTEdisease. Chest 2016;149:315 – 352. 2.KaufmanJA,KinneyTB,StreiffMB,SingRF,ProctorMC,BeckerD,CipolleM, ComerotaAJ,MillwardSF,RogersFB.Guidelinesfortheuseofretrievableand convertiblevenacava lters:reportfromtheSocietyofInterventional Radiologymultidisciplinaryconsensusconference. JVascIntervRadiol 2006;17:449 – 459. 3.KaufmanJA,RundbackJH,KeeST,GeertsW,GillespieD,KahnSR,KearonC, RectenwaldJ,RogersFB,StavropoulosSW.Developmentofaresearchagenda forinferiorvenacava lters:proceedingsfromamultidisciplinaryresearch consensuspanel. JVascIntervRadiol .2009;20:697 – 707. 4.SteinPD,KayaliF,OlsonRE.Twenty-one-yeartrendsintheuseofinferiorvena cava lters. ArchInternMed .2004;164:1541 – 1545. 5.SteinPD,MattaF,HullRD.Increasinguseofvenacava ltersforpreventionof pulmonaryembolism. 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CardiovascIntervent Radiol .2013;36:1548 – 1561. 40.TaoMJ,MontbriandJM,EisenbergN,SnidermanKW,Roche-NagleG. Temporaryinferiorvenacava lterindications,retrievalrates,andfollow-up managementatamulticentertertiarycareinstitution. JVascSurg 2016;64:430 – 437. 41.WangSL,ChaHH,LinJR,FrancisB,ElizabethW,MartinP,RajanS.Impactof physicianeducationandadedicatedinferiorvenacava ltertrackingsystem oninferiorvenacava lteruseandretrievalratesacrossalargeUShealthcare region. JVascIntervRadiol .2016;27:740 – 748. DOI:10.1161/JAHA.117.006708 JournaloftheAmericanHeartAssociation11 VenaCavaFilterRetrieval BrownetalORIGINALRESEARCH