anti-xaand aptt for ufh monitoring · no bleeding. baseline pt 20 sec (nl 11-13 sec), inr 2.1, ......
TRANSCRIPT
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James Zehnder, MDProfessor of Pathology and Medicine (Hematology)
Stanford University, Stanford, CA
May 6, 2017International Symposium on Technical Innovations in Laboratory Hematology
Honolulu, HI
Anti-Xa and APTT for UFH Monitoring
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Casepresentation:57yearoldmanwithend-stageliverdisease
� Hospitalizedforlivertransplantevaluation� Hxportalhypertension,esophagealvarices,nobleeding.
� BaselinePT20sec(nl11-13sec),INR2.1,aPTT46sec(nl21-34sec)Totalbilirubin4.6
� Whileinhospital,patientdevelopedLLEfemoralveinDVT
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• Thepatient’sINRof2.1atbaselineindicatesthatheisauto-anticoagulated– A:True– B:False
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Patterns of Prohemostatic and Antihemostatic Drivers in the Different Phases of Hemostasis in Patients with Chronic Liver Disease.
Tripodi A, Mannucci PM. N Engl J Med 2011;365:147-156
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Summary• Conventional wisdom is that chronic liver disease is an acquired
bleeding disorder.• However, the imbalance between procoagulant and
anticoagulant activities can also lead to thrombosis.• Studies are needed to assess the value of anticoagulants.
TripodiA,MannucciPM,NEJM2011
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Casepresentation:57yearoldmanwithend-stageliverdiseaseandDVT- questions
◦ Thecliniciansdecidethattheriskofthrombosisextension/PEisgreaterthantheriskofbleedingfromanticoagulation.Theyaskforyouradvicegivenissueswithmonitoring.Whatwouldyourecommend?◦ A:Heparin◦ B:Argatroban◦ C:DOAC◦ D:LMWH◦ E:Warfarin◦ F:I’mgoingwiththefilterinthisone
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Casepresentation:57yearoldmanwithend-stageliverdisease:Problemswithheparinmonitoring
• PatientstartedonUFHusingnomogramtargetingananti-Xaactivityrangeof0.3-0.7anti-Xa U/ml,andalsocheckingPTTforthefirst3determinations
• 24hourslater,anti-Xais0.7,butaPTTis>300sec• Thecliniciansareangryandsaythelabisgivingtheminaccurate
results• Whatdoyoudonow?
– A:Apologizeforthelaboratoryerror– B:Suggeststopmeasuringanti-Xa anddecreaseheparinuntilPTTin
therapeuticrange– C:Targetanti-Xa to0.3(lowerendofrangeratherthanupper)and
continuetomonitorPTT– D:ChangetoLMWHandstopmonitoring– E:ChangetoaDOACandstopmonitoring– F:Stopanticoagulationandputinafilter
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Mastcells:sourceofheparin,limitdknowledgere:biologicalfunction
ZehnderJL,GalliSJ:Nature 400,1999
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Heparinproductionfrompigintestines
Photo:NewYorkTimes,April2008
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Wound
Tissue FactorVIIa
Xa
Thrombin
Fibrin
XIa
Control of theClotting Cascade
IXa
Every component of the clotting cascade is regulated by its physiologic inhibitor
TFPI/Xa
AT/heparin
PC/PS/TM
Va
VIIIa
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Abriefhistoryofclinicaluseofheparin
• Priortoheparinuse:– Standardtreatmentofphlebitiswasbedrestandobservation
– Inoneseriesof29patientswithLEDVT• 24/29spreadtofemoralvein• 10/29developedcontralateralDVT• 11/29hadPE,2fatal.
Bauer G. The introduction of heparin therapy in cases of early thrombosis. Circulation 1959;19:108-109.
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Firstrandomizedcontrolledtrialofheparintherapy:BarrittandJordan,1960
• VTEdiagnosedonclinicalgrounds• Patientsrandomizedtoobservationortherapywithheparin
andnicoumalonefor2weeks– Heparin10,000UIVq6h,nomonitoring– NicoumalonedosedtoPT2-3Xcontrol
• Interimanalysisoffirst35patients:– Observationarm:5/16diedfromPE– Treatmentarm:0/16died– 38subsequentpatientsenrolledintreatmentarm,nofatalPE
• StronglyinfluencedclinicalpracticeinfavorofRxVTE
Barritt DW, Jordan SC. Anticoagulant drugs in the treatment of pulmonary embolism. A controlled trial. Lancet 1960;1:1309-1312
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Shouldheparinbemonitored?
InitialtrialsdosedonaweightbasiswithoutmonitoringConsideringrecenthx ofintroductionofLMWHs,DOACs- ifheparinwasbeingintroducedasanewanticoagulantin2017,wouldtherebeamonitoringrequirement?
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HeparinMonitoring• 1972:PTT1.5-2.5baselineassociatedwithdecreasedriskrecurrentVTE
• Correlatedwithrangeof0.2-0.4U/mLbyprotaminetitrationor0.35-0.67U/mLanti-Xa activity
• EffectofheparinonPTTwidelyvariableamongdifferentreagent/instrumentsystems
• BasisofCAPrequirementtocalibrateaPTTtherapeuticrangetoprotaminetitrationof0.2-0.4U/mLoranti-Xaactivityof0.3-0.7U/mL
Basu D, Gallus A, Hirsh J, et al. A prospective study of the value of monitoring heparin treatment with the activated partial thromboplastin time. N Engl J Med 1972; Chiu HM, Hirsh J, Yung WL, et al. Relationship between the anticoagulant and antithrombotic effects of heparin in experimental venous thrombosis. Blood 1977; Levine MN, Hirsh J, Gent M, et al. A randomized trial comparing activated thromboplastin time with heparin assay in patients with acute venous thromboembolism requiring large daily doses of heparin. Arch Intern Med 1994
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Clotting Pathways: Intrinsic, Common (measured by PTT)
Negativelychargedsurface
XIa
IXa
Xa
II IIa
Fibrinogen Fibrin
VIIIaa
Va
FactorXII
PartialThromboplastinTime(PTT):•Measuresclottingtimeaftercontactfactorsactivated.
•Usedtomonitorheparinanticoagulanttherapy
•InVitroassessmentofintegrityofintrinsicandcommonpathways
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PTTissues• Appealingasafunctional“physiologic”readout ofthe
degreeofanticoagulation• However,interpretationofPTTiscontext-dependent:
– PTT of70seccouldbedueto:• Therapeuticlevelsofheparin• FactorVIIIdeficiencywithbleedingrisk• LAwiththrombosisrisk• FactorXIIdeficiencywithnobleedingorthrombosisrisk
• PTTreagentswidelyvariableintheirsensitivitytoheparinandotherbiologicalinterferences
• NoINRequivalenttoharmonizedifferentreagent/instrumentsystems
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Shannon M. Bates, and Jeffrey I. Weitz Circulation. 2005;112:e53-e60
Copyright © American Heart Association, Inc. All rights reserved.
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Idealtestcharacteristicsforanticoagulantmonitoring– PTTandanti-Xa
• Theassayresultshouldhaveawell-definedandpreferablylinearrelationshipwithclinicaloutcome(recurrentthrombosisandbleeding)
• Assayshouldhavegoodprecisionandbewell-standardizedamonglaboratoriesandassayreagents– partialcredit
• Theassayshouldbereadilyavailableandinexpensive- yesPTT
Eikelboom andHirsch,Thromb Haemost 2006
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Backtothequestion:Shouldheparinbemonitored?
EvidencesupportingmonitoringisweakNationalPatientSafetygoalsmandateastandardmethodofmonitoringheparinWearestuckwithit.Stanfordprotocol(EMRheparinordersets):
CheckbaselinePT,PTT,plateletsPTTandanti-Xa testedfirst3determinationsFurthermanagementperanti-Xa-basednomogramsinEpicEMRAllpatientandlabdataisavailableforstudyinaclinicaldatarepository
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PTT vs anti –Xa results
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Decreased sensitivity of aPTTto heparin—heparin resistance
high VIII/Fibrinogen
Interference with APTT assessment of heparin effect
pregnancyrenal disease
inflammation
acquiredfactor deficiency
Increased sensitivity of aPTTto heparin
LupusAnticoagulant
congenitalfactor
deficiency(includes
mild FXII def.)
liver disease
warfarin
DICNone of these interfere with determination of heparin activity by anti-Xa assay
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a47Yfemalewithh/oMarfan syndromeanda5.3cmaorticrootaneurysms/prepairHematologyconsultedforetiologyofhighPTTaftersurgery.Patientwasnotonanyanticoagulant.
Caseexample:elevatedaPTTaftersurgery
STAGO(Stagoreagents) ACLTOP(ILreagents)
DrawtimeaPTT
(nL:23.8-35.7s)
anti-Xa(UFH)
INR(nl:0.9-1.2)
CRPaPTT-ss
(nl:23.3-37.2s)
aPTT-sp(nl:23.3-37.2
s)
anti-Xa(UFH)(nl:<0.04U/dl)
SCT DRVVT
11/23/2016 26.0 1.0
12/8/2016 90.5 1.2 29.9 50.1 0.00 Neg Neg
Cardiovascularsurgeryon12/5/2016*
8.4
Baseline
AfterSurgery
Note:StagoaPTTreagent:aPTTautomated5;Instrumentationlaboratory(IL)reagent:aPTT-ss:aPTTSynthASil,aPTT-sp:lupussensitiveaPTTreagent
DidmarkedlyelevatedCRPprolongPTT?
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C-reactiveproteinandphosphocholine binding
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Crystal structure of C-reactive protein complexed with phosphocholine from Thompson et al.
Steven Black et al. J. Biol. Chem. 2004;279:48487-48490
©2004 by American Society for Biochemistry and Molecular Biology
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Falseprolongationoftheactivatedpartialthromboplastintime(aPTT)ininflammatorypatients:interferenceofC-reactiveprotein
BritishJournalofHaematologyVolume157,Issue3,pages394-395,9JAN2012DOI:10.1111/j.1365-2141.2011.08990.xhttp://onlinelibrary.wiley.com/doi/10.1111/j.1365-2141.2011.08990.x/full#f1
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STAGO(STAGOreagent) ACLTOP(ILreagents)
DrawtimeaPTT
(nL:23.8-35.7s)
anti-Xa(UFH)
(nl:<0.04U/dl)
INR(nl:0.9-1.2)
CRP(nl:<0.9mg/dl)
aPTT-ss(nl:23.2-36.0s)
aPTT-sp(nl:23.3-37.2s)
anti-Xa
(UFH)(nl:<0.04U/dl)
ATIII(nl:83-128%)
TT(nl:11.8- 14.4s)
SCT dRVVT FXII FXI FIX FVIII FX FVII
VWACT(nl:44-165%)
9/21/161307 33.0 <0.10 1.1
9/22/160239 50.2 0.16
9/24/160705 97.2 0.42
9/27/162111 53.3 0.18
9/28/161125 72.9 0.27 1.0
9/29/2016 9/29/16underwentCABG,MVrepair,Procedurewentuneventfully.Discordance notedaftersurgery. coagulationworkupstarted:
9/30/161617 84.3 <0.10 17.1 29.9 41.7 0.00 13.6 128 227 75
9/30/161703 16.3 30.0 49.6 0.07 16.9 128 207 68
10/1/160330 120.8 <0.10 1.3 21.5 30.9 54.4 0.02 15.6 Neg Neg
10/1/160945 116.5 <0.10 19.6 31.3 53.0 0.02 15.1
10/1/161959 37.7 73.1 0.10 78 20.8 104 164 248 317
10/2/160010 146.4 <0.10 21.4 38.1 86.3 0.09 21.2 65.8
10/2/160351 1.3 45.0 90.9 0.13 27.6
10/4/161835 107.9 <0.1 1.5 32.0 0.03 14.0 62
AnotherpatientwithelevatedaPTT aftersurgery
Therapeuticrangefrom0.3- 0.7anti-Xa U/mLcorrespondstoaPTTof78– 121secondsintheStanfordcoagulationlaboratoryusingaStagoSTA-RautomatedinstrumentandPTT-automatereagent.
aPTTandanti-XA(UFH)correlateswellbeforesurgery
A69Yfemales/pmitralvalvereplacementwith1vCABG,whoisbeingevaluatedbyHematologyconsultteamforetiologyofhighPTT.
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Concordance of aPTT vs anti-Xa
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Initialstudy:500patientswithpairedPTT/anti- Xa data
Patient Characteristic
Only PTT > anti-XaN=85
Only PTT= anti-XaN=112
StatisticP Value
Median age (y) 63 63 NSNumber male (%) 53 (62) 61 (54) NSNumber (%) on warfarin
47 (55) 23 (21) <0.001
Number (%) with elevated baseline PT prior to starting UFH
67/80 (84) 48/98 (49) <0.001
Number (%) with elevated baseline PTT prior to starting UFH
53/77 (69) 9/93 (10) <0.001
Number (%) dead within 30 days of first data pair
18(21) 4 (4) <0.001
PriceEA1,JinJ,NguyenHM,KrishnanG,BowenR,ZehnderJL.DiscordantaPTT andanti-Xa valuesandoutcomesinhospitalizedpatientstreatedwithintravenousunfractionatedheparin.AnnPharmacother. 2013Feb;47(2):151-8
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Leverage extensive in-patient data from StanfordElectronic Health Record (EHR) and the StanfordCenter for Clinical Informatics databases (STRIDE)toward precisely characterizing the clinical andlaboratory factors associated with adverseoutcomes in this population.
Followup study 2009-2016, 7700 patients
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Follow-up study 2009-2016Patient Demographic Overview
Gender n, (%)
Male 4,522 (58.9)
Female 3,224 (41.1)
Race
Asian 804 (10.1)
Black 416 (7.2)
White 4,876 (60.5)
Other 1,650 (22.2)
Ethnicity
Non-Hispanic 6,472 (82.5)
Hispanic 928 (13.4)
Unknown 346 (4.1)
Death
Recorded 2,159 (27.9)
Within 30 days of testing
865 (11.1)
Within 3 days of testing
360 (4.6)
Total 7746
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DISTRIBUTION AND MORTALITY BY PAIRED aPTT/Anti-XA TEST RELATIONSHIP
High aPTT2,175
(461, 21%)
High Both1681
(229,14%)
High anti-Xa
1125 (108, 9%)
Normal38,647
(3567, 9%)
Paired Tests Per Quadrant, (mortality, n, % within 30 days)
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DISTRIBUTION AND MORTALITY BY PATIENT
High aPTT1023
(202, 19.7%)
High Both1135
(157,14%)
High anti-Xa
739 (71, 9.6%)
Normal7434
(800, 10.8%)
# of Patients Per Quadrant, (mortality, n, % within 30 days)
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Increased30dmortalityriskwithPTT>anti-Xa
Category Mortality p-value
Normal 800/7434(10.8)
ElevatedPTT
202/1023(19.7)
9.46x10-13*
ElevatedAnti-Xa
71/739(9.6)
0.416
ElevatedBoth
157/1135(13.8)
0.008
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CONCLUSIONSOur studies demonstrate the extent of discordance in aPTTand anti-Xa values among hospitalized patients in atertiary/quarternary level care setting on anticoagulation.
In this setting, patients with elevated aPTT and therapeuticrange anti-Xa levels have a significantly higher rate ofmortality.
This elevated mortality is significantly higher than patientswith both elevated aPTT and anti-Xa, suggesting potentiallyserious underlying disease and therefore, opportunity forrevaluation of the indication for anticoagulation andanticoagulation goals.
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FUTURE WORK
Sub-group analyses on high aPTT patients exploringadditional mortality factors.
Value-based assessment of relative-utility of the two tests inspecific subgroup of patients.
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Casepresentation:57yearoldmanwithend-stageliverdisease:problemswithheparintherapy
• PatientstartedonUFHusingnomogramtargetingananti-Xaactivityrangeof0.3-0.7anti-XaU/ml
• 24hourslater,anti-Xais0.7,butaPTTis>300sec• Thecliniciansareangryandsaythelabisgivingtheminaccurate
results• Whatdoyoudonow?
– A:Apologizeforthelaboratoryerror– B:Suggeststopmeasuringanti-Xa anddecreaseheparinuntilPTTin
therapeuticrange– C:Targetanti-Xa to0.3(lowerendofrangeratherthanupper)and
continuetomonitorPTT– D:ChangetoLMWHandstopmonitoring– E:ChangetoaDOACandstopmonitoring– F:Stopanticoagulationandputinafilter
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Casepresentation:57yearoldmanwithend-stageliverdisease:outcome
• UFHinfusionwasdecreasedtotargetof0.3anti-Xa U/mL– 6hourslater,anti-Xa 0.32,aPTT 120sec– Felttorepresentabalancebetweenadeqauteanticoagulationandbleedingrisk
– Patientdidwell,transitionedtowarfarin
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Summary:PTTvs.anti-Xa forUFHmonitoring
• PTTandXavaluesarefrequentlydiscordantininpatientsonUFH• BaselineprolongationofPToraPTTisafrequentcauseofPTT>Xa
onUFH• Inflammatorystatescanincrease(CRP)ordecrease(Fn)sensitivity
toaPTT• DifferentaPTT reagent/instrumentsystemshavewidelyvariable
sensitivitytoheparin;usingratioof1.5-2.5tendstounderdose• Neithertestisideal;thebasisformonitoringingeneralisweak• Intertiary/quarternary levelhospitalswherecomorbiditiesaffecting
aPTT sensitivitytohepariniscommon,usefultohaveanti-Xa option• MeasuringbothPTTandXamayhaveutilityinselectedpatients• BetterstandardizationofaPTT reagentswithrespecttoheparin
effectandknowninterferenceswouldbeideal
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Acknowledgements
SaurabhGombar MD,PhDAnandi KrishnanPhDJingJinMD,CLSDepartmentofPathology,StanfordUniversityClinicalLaboratories,StanfordHealthCare
stanford_edu.htm
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Thereagentdiffisrightthere!
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CRPPatient Drawtime aPTT anti-Xa(UFH) PT/INR TT Rept aPTT aPTT-sp HAL ATIII INR TT FXII FXI FVIII FIX FV FX FVII VWACTPatient4 11/3/20162122 113.4 27.9/2.8 55.3 43.3/3.69
11/4/160743 77.1 16.9/1.5 <13.0 9.5 39.7 48.7 0.00 14.3/1.28 13.0
10/25/161244 71.2 0.23 1.510/27/161636 116.6 2.710/29/160610 62.2 <0.10 1.510/29/161610 74.2 12.7 31.1 56.5 0.05 1.27 15.110/29/161723 12.3 29.4 47.2 0.00 1.24 13.9 Drvvt;Screen:36.6[nl:29-46sec]Confirm:34.0Normalizedratio:0.9510/30/160544 73.7 1.3 15.2 34.3 61.1 0.04 71 1.26 14.9
9/21/161307 33.0 <0.10 1.19/22/160239 50.2 0.169/24/160705 97.2 0.429/27/162111 53.3 0.189/28/161125 72.9 0.27 1.09/30/161617 84.3 <0.10 17.1 29.9 41.7 0.00 13.6 227 128 759/30/161703 16.3 30.0 49.6 0.07 16.9 207 128 68.410/1/160330 120.8 <0.10 15.9/1.3 21.5 30.9 54.4 0.02 15.610/1/160945 116.5 <0.10 19.6 31.3 53.0 0.02 15.1
10/1/161635 108.2 <0.10 dRVVTneg10/1/161959 37.7 73.1 0.10 78 20.8 104 248 164 31710/2/160010 146.4 <0.10 21.4 38.1 86.3 0.09 21.2 65.810/2/160351 15.9/1.3 45.0 90.9 0.13 27.610/4/161835 107.9 <0.1 17.1/1.5 32.0 0.03 14.0 6210/7/161419 4.211/3/20160416 >300.0 0.44 21.5/2.0 131.7 0.489/22/162016 29.3 1.1
9/25/161749 60.39/25/161813 27.79/26/171147 <13.0 12.99/26/161536 60.29/26/161750 26.8 28.7 50.3 0.00 86 14.0 73 68 179.2 1449/27/160317 79.6 <0.10 14.2/1.2 15.9 31.5 79.8 0.02 15.610/1/161556 81.6 <0.10 13.8/1.1 32.9 49.8 0.03 19.910/2/150515 45.6 26.9 41.4 0.00 16.510/2/160935 27.3 46.3 0.00 15.2 101 69
4/24/20171259 1.14/25/20172017 173.5 0.24 8.84/25/20172122 176.3 0.23 55.9 >400.0 0.27 92.5 DRVVTneg4/25/20172358 51.8 <0.10 29.5 43.4 0.00 15.94/26/20170353 90.4 <0.10 1.3 29.5 42.2 0.00 68 16.3
Patient5
Patient1
NegativeratiosfromLACpairedtestsSCTandDRVVT(couldneutrlaizeHepupto1.0u/ml)indicatingLACnegative.
STAGO ACLTOP(ILreagents)
Patient3
Patient2
PT:26.6/2.31
9/29/16underwentCABG,MVrepair,Procedurewentuneventfully.Discordanthappenedrightaftersurgery
UFH:300Units/hr:3mL/hrsince10/29/16
9/23/16:WenttoORforMVRandAVR.Receivedheparin25000unit(s)IVprndose.at9:30amthen5000unit(s)prndoseat9:30am.Wasonxareltobeforesurgery.
Dischargedafter10/10/16withtherapeuticalwarfarin.Thengotre-admittedon10/28/16forsubtherapeuticINR.Heparinwasstartedtobridgewarfarin
Aorticvalvestenosiss/pAVRon4/24
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Casepresentation:57yearoldmanwithend-stageliverdisease:problemswithheparintherapy
• PatientstartedonUFHusingnomogramtargetingananti-Xaactivityrangeof0.3-0.7anti-XaU/ml
• 24hourslater,anti-Xais0.7,butaPTTis>300sec• WhyaretheaPTTandanti-Xadiscordant?
– A:BecausebaselinePTandPTTprolonged– B:Anti-Xaisnotvalidinliverdisease– C:Laboratoryerror– D:Testinterferenceduetoincreasedbilibrubin
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SyntheticPentasaccharide
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*P=0.0316comparedtoOnlyaPTT=anti-Xa group#P=0.0202comparedtoOnlyaPTT=anti-Xa group§P=0.0008comparedtoOnlyaPTT=anti-Xa group
Outcome Two Consecutive aPTT>anti-Xa
(n=163)
Only aPTT=anti-Xa(n=112)
Only aPTT>anti-Xa(n=85)
Number (%) with major bleeding within 21 days following first data pair
15 (9)* 3(3) 5(6)
Number (%) with new thrombotic event within 21 days following first data pair
9 (6) 2 (2) 3 (4)
Number (%) dead within 30 days following first data pair
23 (14) # 6 (5) 18 (21) §
Majorbleeding,thrombosisanddeathinthethreepatientgroups
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Idealtestcharacteristicsforanticoagulantmonitoring
• Theassayresultshouldhaveawell-definedandpreferablylinearrelationshipwithclinicaloutcome(recurrentthrombosisandbleeding)
• Assayshouldhavegoodprecisionandbewell-standardizedamonglaboratoriesandassayreagents.
• Theassayshouldbereadilyavailableandinexpensive.
Eikelboom andHirsch,Thromb Haemost 2006
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AssociationofaPTT withclinicaloutcomes:Thrombosis
• RxofacuteVTE– AchievingtherapeuticaPTTwithin24hassociatedwithdecreasedrisk– Howeversubsequentmeta-analysesofVTERxtrials:Ifheparingivenasinitialbolusthenatleast30,000U/24hnosignificantassociationofoutcomewiththerapeuticaPTT infirst24h.
HullRD,Raskob GE,Rosenbloom D,etal.ArchInternMed1992;Anand S,GinsbergJS,Kearon C,etal.ArchInternMed1996; Anand SS,BatesS,GinsbergJS,etal.ArchInternMed1992.
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AssociationofaPTT withclinicaloutcomes:Bleeding
• Increaseinmajorbleedingseeninsomebutnotallstudies:– Hulletal(ArchInt Med1992):Noassociationwithsupratherapeutic aPTT andmajorbleeding
– Anand etal(ArchInt Med1992):SubgroupanalysisofOASIS-II– 7%increaseinbleedingrisk/10secaPTTprolongation
• Patientriskfactors:age,comorbidity,recentsurgery
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ComparedtotheOnlyaPTT=anti-XaPatientGroup(6outof112,5%),30-daymortalitywassignificantlyhigherintheOnlyaPTT >anti-Xapatientgroup18of85(21%)(p<0.001).Nineof17(53%)ofthedeceasedpatientsinOnlyaPTT >anti-XapatientgrouphadelevationsinbothPTandaPTT atbaseline.(Excludedonedeceasedpatientwhodidn’thavebaselinePTandaPTT.)
9of1753%
5of1729%
2of1712%
1of176%
0
1
2
3
4
5
6
7
8
9
10
BaselinePT,aPTTelevated
BaselinePTelevated,aPTTnormal
BaselineaPTTelevated,PTnormal
BaselinePT,aPTTwithin normallimits
BaselinePT,aPTT Status