1. The hypercoagulability panel in stroke: Which tests should be done?
Michael Rippee, MD
Assistant Professor
Department of Neurology
University of Kansas Medical Center

2. A. Yes B. No Case #1: JS 38 y/o woman
Sudden onset dizzness, right sided HA, slurred speech, diplopia, left arm weakness, right sided facial droop
H/o headaches
MRI reveals right thalamic infarct
Hypercoagulable panel?
A. Yes B. No

3. Case #1: JS AT3 126 (H) (nl = 80-120) Cardiolipin
IgG 3.6
IgM 14.9 (H) (nl = <12.5)
Activated Protein C Activity nl
Protein C & S nl
DRVVT nl
Hex lupus anticoagulant not done
Factor 2 gene mutation neg
ANA neg
Beta2 glycoprotein neg
Homocysteine nl

4. Stroke Causes in Young Which is most common? A. Hypercoagulable State
B. Cardioembolism
C. Atherosclerotic factors
D. Other determined causes (e.g. dissection)

5. Risk factors: Young Adult
Most frequent risk factors:
Dyslipidemia 60%
Smoking 44%
Hypertension 39%
Most common etiologies:
Cardioembolism 20%
Cervicocephalic arterial dissection 15%
Proportions of small vessel disease (14%) and large artery atherosclerosis (8%) increased beginning at age 30 to 35
Frequency of undetermined etiology (33%) decreased with age

7. A. Yes B. No Case #2: TW 34 y/o man
Nausea, vision loss (quadrantanopia), HA
MRI revealed right occipito-temporal infarct
No fam hx
Otherwise healthy
LDL 163
Hypercoagulable panel?
A. Yes B. No

8. Case #2: TW AT3 nl Factor 8 nl Cardiolipin Abs nl
Activated Protein C nl
Protein C & S nl
DRVVT nl
Hex lupus anticoagulant not done
Factor 2 gene mutation neg
Homocysteine nl
ANA neg
MTHFR neg
Angiogram confirmed vertebral artery dissection

9. Hypercoagulabilty & Stroke
The role of hypercoagulable states in strokes is controversial
Blood disorders implicated 5-10%
In patients without other traditional risk factors and etiologies for stroke, hypercoagulable state should be considered
Abnormal findings on routine screening coagulation tests (aPTT) should also raise a red flag
Hypercoagulable state may be more important in the younger patient with stroke

10. Hypercoagulabilty & Stroke
Hypercoagulability should be suspected in patients with ischemic stroke who have the following characteristics:
Younger than 50 years with no obvious cause of stroke
History of multiple unexplained strokes
Previous history of venous thrombosis
Family history of thrombosis
Abnormalities on routine screening coagulation tests

11. Thrombosis
Virchow’s triad for venous thrombosis

12. Hypercoagulable State
Defined as a group of inherited or acquired conditions associated with a predisposition to:
Venous thrombosis including:
Upper and lower extremity deep venous thrombosis with or without pulmonary embolism
Cerebral venous thrombosis
Intra-abdominal venous thrombosis
Arterial thrombosis including:
Myocardial infarction
Stroke
Acute limb ischemia
Splanchnic ischemia
Venous thromboembolic disease is the most common
Most inherited conditions appear to increase only the risk of venous thrombosis
Some of the acquired conditions have been associated with both venous and arterial thrombosis
Age of onset for initial thrombotic event is typically before age 45

13. Hypercoagulable State
Recent data support the role of more than one prothrombotic mutation or additional acquired conditions to be necessary for clinically apparent clotting
Immobilization
Surgery
Cancer
Pregnancy
Use of hormone therapy or oral contraceptive medication
Clues to the diagnosis:
History of recurrent fetal loss
Thrombocytopenia
Livedo reticularis or Sneddon syndrome
Skin necrosis during initiation of oral anticoagulant therapy
Protein C and/or S deficiency

15. Hypercoagulable States
Inherited
Acquired
Factor V Leiden
Prothrombin gene mutation
Anti-thrombin deficiency
Protein C & S deficiencies
Elevated homocysteine
Dysfibrinogenemia
Elevated Factor VIII levels
Abnormal fibrinolytic system
Sickle Cell disease
Antiphospholipid antibody syndrome
Supplemental estrogen use
HIT
Cancer
Medications
Central venous catheter
Obesity
Pregnancy

16. Hypercoagulable workup
PT and PTT
Protein C
Protein S
Antithrombin III activity
Prothrombin gene mutations
Factor V Leiden gene mutation
Activated Protein C resistance
Anticardiolipin antibodies (IgG and IgM)
Beta2-glycoprotein I antibodies (IgG and IgM)
Lupus anticoagulant tests
dilute Russell viper venom time
dilute activated PTT
hexagonal phospholipid
Homocysteine
Factor VIII activity
D-dimer
Lipoprotein (a)
MTHFR

17. Hypercoagulable workup
How much does it cost?
A. $450
B. $900
C. $2200
D. $5000

18. Copyright © 2012 American Medical Association. All rights reserved.
From: Hypercoagulability Syndromes
Arch Intern Med. 2001;161(20): doi: /pubs.Arch Intern Med.-ISSN ira00051
Figure Legend: $
Costs of Hypercoagulable Workup at the University of Miami
Date of download: 9/25/2012
Copyright © 2012 American Medical Association. All rights reserved.

19. Hypercoagulable workup: Cost
A lot of facilities conduct these as send-out tests
Quest $1300-$2500 (avg $2000)
Pts bill $2200-$3000
Safe estimates are $2-4K
Generally the panel is repeated at least once!

20. So which test to order?

21. Case #3: TS 35 y/o woman Severe, unrelenting HA
Venous sinus thrombosis
On OCPs
No Fam Hx

22. What tests to order?
A. Routine stroke, but no hypercoagulable
B. Full hypercoagulable panel
C. Anti-cardiolipin, lupus anticoagulant panels only
D. Protein C & S, AT3, Factor V Leiden, Prothrombin mutation only
E. None

23. Case #3: TS Cardiolipin nl Protein C&S nl DRVVT nl
Hex lupus anticoagulant 11 (H) (nl <8)
Factor 2 mutation neg
ANA neg
RF neg
Beta2 glycoprotein nl
9 mos later
Hex lupus 6.1
DRVVT 47.6

24. Case #4: JR 45 y/o man Left hemiparesis & facial droop
MRI showed right pontine infarct
LDL 129, quit smoking 3 weeks prior to stroke
No Fam Hx

25. What tests to order?
A. Routine stroke, but no hypercoagulable
B. Full hypercoagulable panel
C. Anti-cardiolipin, lupus anticoagulant panels only
D. Protein C & S, AT3, Factor V Leiden, Prothrombin mutation only
E. None

26. Case #4: JR Antiphospholipid Ab Syndrome October Cardiolipin
IgG 6.8
IgM 13.0 (H) (nl = <12.5)
Protein C & S nL
November
AT3 nl
DRVVT nl
Homocysteine 18.6 (H) (nl <15)
Beta2 glycoprotein IgG 16 (H) (nl <15)
IgM nl
IgA nl
Alphagalactosidase (Fabry’s) ordered but not done due to cost
April
Cardiolipin tests normalized
Factor 8 nL
Activated Protein C nl
MTHFR neg
Hex Lupus Anticoagulant nl
Factor 2 mutation neg
Factor V Leiden ordered but not done
Antiphospholipid Ab Syndrome

27. Which tests to order?
Keep in mind whether the results will influence therapy and/or patient outcome
Not advocated to screen all stroke patients for a “hypercoagulable workup”
Typically, will have a prior history of one or more unexplained thromboembolic events
Yield for diagnosing a hypercoagulable state is typically greatest for:
Young stroke patients
Family history of thrombosis
No other explanations for their stroke (cryptogenic stroke)
Assaying for specific prothrombotic states has limitations based on the assay and the timing of the test
Levine SR. Hypercoagulable States & Stroke: A Selective Review. CNS Spectr. 2005;10(7):

28. Which tests to order?
Blood work to diagnose a hypercoagulable state does not preclude the routine work up of any stroke patient:
Neuroimaging (brain CT and MRI)
Carotid ultrasound
Echocardiogram
Basic blood tests including a CBC, prothrombin time (PT), partial thromboplastin time (aPTT), and a fasting lipid profile
Important points to be noted before ordering a work-up for hypercoagulable state:
Use of anticoagulation can affect results of aCL, LA, protein C, protein S, and antithrombin III
Results should be repeated in 4–8 weeks to exclude false positives that may be related to an acute phase reaction
Vaishnav, AG. (2008). “Hypercoagulable States and Stroke.” In D. Alway, J.W. Cole (Eds.). Stroke Essentials for Primary Care. Human Press.

29. Which disorders associated with stroke?
Prothrombotic states implicated in ischemic stroke:
Deficiencies of factors inhibiting coagulation
Antithrombin III, protein S, and protein C
Increased levels of factors promoting coagulation
Factors V and VII
Decreased activity in the fibrinolytic pathway
Plasminogen or plasminogen activator deficiencies

30. Association with stroke
Inherited thrombophilias (eg, protein C, protein S, or antithrombin III deficiency; factor V Leiden; prothrombin G20210A mutation), and MTHFR
Rarely contribute to adult stroke
May play a larger role in pediatric stroke
Studies in younger patients (<55 years of age) have shown an association between prothrombotic genetic variants and ischemic stroke
Remains controversial in an older population with vascular risk factors
Even in the young, results have been inconsistent
Small study of cryptogenic stroke patients <50 years of age
Increased risk associated with the PT G20210A mutation
No significant association with FVL
2 other studies of young (<50 years) patients
Found no association between ischemic stroke and the FVL, PT G20210A, or MTHFR
The association between APL antibodies and stroke is strongest for young adults (<50 years of age)
Furie KL, et al. Guidelines for the Prevention of Stroke in Patients with Stroke or Transient Ischemic Attack: A Guideline for Healthcare Professionals. Stroke. 2011;42:

31. Hereditary Hypercoagulable Disorders
Factor V Leiden mutation
Most common hereditary hypercoagulable disorder associated with cerebral venous thrombosis
Scant evidence of its association with arterial strokes
Caused by a mutation that makes Factor V resistant to inactivation by activated Protein C (APC resistance)
APC resistance can also be induced by pregnancy and estrogen
Homozygous forms are much more prone to thrombosis than a heterozygous mutation
Vaishnav, AG. (2008). “Hypercoagulable States and Stroke.” In D. Alway, J.W. Cole (Eds.). Stroke Essentials for Primary Care. Human Press.

32. Hereditary Hypercoagulable Disorders
Antithrombin III, Protein C, and Protein S deficiency:
These conditions are relatively rare
More potent cause of cerebral venous thrombosis than Factor V Leiden
No evidence of their association with arterial strokes
Prothrombin gene mutation (G20210A)
Occurs in approximately 2–5% of individuals and in itself is a weak procoagulant in its action

33. Hereditary Hypercoagulable Disorders
Protein C
Used to screen for a primary protein C deficiency or to diagnose protein C deficiency secondary to dysproteinemia
To confirm protein C deficiency, and to differentiate it from dysproteinemia, the protein C antigen is measured
Protein S
Activity is measured by a functional assay
Both the total Protein S and free Protein S functional assays are performed because the free assay is a more reliable marker for hypercoagulability
To confirm protein S deficiency, and to differentiate it from dysproteinemia, the protein S antigen is measured
Antithrombin III
It is recommended to repeat the level in 4–6 weeks if a deficiency was initially found in the setting of an acute thrombotic event, pregnancy, or warfarin use
Vaishnav, AG. (2008). “Hypercoagulable States and Stroke.” In D. Alway, J.W. Cole (Eds.). Stroke Essentials for Primary Care. Human Press.

34. Antiphospholipid Antibody (aPL) Syndrome
Antiphospholipids have been associated with both arterial and venous strokes
The two major types of clinically relevant aPLs:
Anticardiolipin antibodies (aCLs)
Require the presence of serum cofactor beta-2 glycoprotein for binding
Lupus anticoagulant (LA)
May not require the presence of beta-2 glycoprotein
About 70% of patients with aPS have both aCL and LA.
Antiphospholipid antibody syndrome (APS) is defined as both:
Thrombosis or recurrent, unexplained fetal loss AND
aCLs (IgG or IgM) of medium to high titres or LA on at least two occasions at least 8 weeks apart
Patients with primary APS do not have systemic lupus erythematosus (SLE) or any other underlying autoimmune disorders
Patients with aPLs suffer from both venous and arterial strokes
Vaishnav, AG. (2008). “Hypercoagulable States and Stroke.” In D. Alway, J.W. Cole (Eds.). Stroke Essentials for Primary Care. Human Press.

35. Antiphospholipid Antibody (aPL) Syndrome

36. Cerebral Venous Sinus Thrombosis
Routine blood studies:
CBC, chemistry panel, PT and aPTT should be performed
Screening for potential prothrombotic conditions that may predispose a person to CVT
Use of contraceptives, underlying inflammatory disease, infectious process
Testing for prothrombotic conditions
Testing for protein C, protein S, and antithrombin deficiency is generally indicated 2 to 4 weeks after completion of anticoagulation
There is a very limited value of testing in the acute setting or in patients taking warfarin
Saposnik G, et al. Diagnosis & Management of Cerebral Venous Thrombosis. Stroke. 2011;42:

37. Strategies for testing

38. Which tests to order?

39. Use of screening tests Screening Test Confirmatory Test
Activated Protein C Resistance
Factor V Leiden PCR
Antithrombin, Protein C & S activity (functional) levels
Antigenic assays
DRVVT
Lupus anticoagulant

40. Selecting tests
Use of pre-test probablity, appropriate selection of patients, and sensitivity/specifity yield higher post-test probabilities

41. Bushnell CB, Goldstein LB
Bushnell CB, Goldstein LB. Screening for Hypercoagulable Syndromes Following Stroke. Current Atherosclerosis Reports. 2003, 5:

42. Common mistakes Ordering too many tests Testing in the acute phase
Specifically ones with a low pre-test probability
Duplicate tests (APC and FVL)
Testing in the acute phase
Testing while on warfarin or heparin

43. Summary
Common causes of venous thrombosis are unlikely to cause stroke
Activated Protein C resistance/Factor V Leiden
Protein C, Protein S, Antithrombin
Prothrombin mutation
This “typical” hypercoagulable panel is low yeild in arterial stroke
These tests are more high yield in CVT
In young patients without known etiology/risk factors anticardiolipin and lupus anticoagulant are high yield
Should also order beta-2 glycoproteins
MTHFR and homocysteine are not helpful
Testing in the acute phase can be misleading
Testing should be done off of heparin or warfarin

44. Questions

45. JM 58 y/o man H/o RA and SLE HLD and tobacco
Driving back from vacation
Developed left sided weakness, facial droop
MRI revealed right hemisphere ischemic stroke
No Fam Hx

46. What tests to order?
A. Routine stroke, but no hypercoagulable
B. Full hypercoagulable panel
C. Anti-cardiolipin, lupus anticoagulant panels only
D. Protein C & S, AT3, Factor V Leiden, Prothrombin mutation only
E. None

47. Hex Lupus Anticoagulant 31 (H) (nl = <8) Cardiolipin
Prolonged aPTT
DRVVT 1.6 (H) (nl = <1.2)
Hex Lupus Anticoagulant 31 (H) (nl = <8)
Cardiolipin
IgG 9.616.2
IgM 20.615.2
Homocysteine 10.7
Anti-phospholipid Ab Syndrome

48. TP 44 y/o woman Admitted with prolonged, severe headache
Found to have extensive venous sinus thrombosis
On OCP, also on HCG diet (shown to increase potential for thrombus)
No Fam Hx

49. What tests to order?
A. Routine stroke, but no hypercoagulable
B. Full hypercoagulable panel
C. Anti-cardiolipin, lupus anticoagulant panels only
D. Protein C & S, AT3, Factor V Leiden, Prothrombin mutation only
E. None

50. Activated PC resistance nL Hex Lupus Anticoagulant nL DRVVT nL
Factor 8: 140 (nl )
Cardiolipin Ab
IgG 4.0
IgM 8.2
Activated PC resistance nL
Hex Lupus Anticoagulant nL
DRVVT nL
Protein C nL
Protein S nL
Factor 2 mutation neg
AT3 130 (H) (nl = )
Beta-2 glycoprotein neg

51. GM 62 y/o man Sudden onset homonymous hemianopia, dizziness/imbalance
MRI confirmed left PCA infarct
H/o hypertension & HLD

52. What tests to order?
A. Routine stroke, but no hypercoagulable
B. Full hypercoagulable panel
C. Anti-cardiolipin, lupus anticoagulant panels only
D. Protein C & S, AT3, Factor V Leiden, Prothrombin mutation only
E. None

53. AT3 nl
Prothrombin gene mutation neg
Homocysteine nl
Cardiolipin Abs nl
Activated protein C nl

54. LP 29 y/o woman Stroke in 2005, found to have PFOclosed
Had sudden vision loss on right side and difficulty forming words
MRI negative
Fam Hx of dysrhythmia but not stroke or blood clots