Haemostasis pp 111-120 | Cite as

Activated Partial Thromboplastin Time

  • Vera Ignjatovic
Part of the Methods in Molecular Biology book series (MIMB, volume 992)


Activated partial thromboplastin time (APTT) is a commonly used coagulation assay that is easy to perform, is affordable, and is therefore performed in most coagulation laboratories, both clinical and research, worldwide. The APTT is based on the principle that in citrated plasma, the addition of a platelet substitute, factor XII activator, and CaCl2 allows for formation of a stable clot. The time required for the formation of a stable clot is recorded in seconds and represents the actual APTT result.

Key words

APTT aPTT PTT Clotting test Heparin monitoring 


  1. 1.
    Langdell RD, Wagner RH, Brinkhous KM (1953) Effect of anti-hemophilic factor on one-stage clotting tests: a presumptive test for hemophilia and a simple one-stage anti-hemophilic factor assay procedure. J Lab Clin Med 41:637–647PubMedGoogle Scholar
  2. 2.
    Proctor RR, Rapaport SI (1961) The partial thromboplastin time with kaolin. A simple screening test for first stage plasma clotting factor deficiencies. Am J Clin Pathol 36:212–219PubMedGoogle Scholar
  3. 3.
    Cohen AJ, Kessler CM (2002) Haemophilia A and B. In: Kitchens CS, Alving BM, Kessler CM (eds) Consultative haemostasis and thrombosis. WB Saunders, Philadelphia, pp 43–56Google Scholar
  4. 4.
    Roberts HR, Escobar MA (2002) Less common congenital disorders of haemostasis. In: Kitchen S, Alving BM, Kessler CM (eds) Consultative haemostasis and thrombosis. WB Saunders, Philadelphia, pp 57–71Google Scholar
  5. 5.
    Triplett DA (2002) Coagulation abnormalities. In: McClatchey KD (ed) Clinical laboratory medicine, 2nd edn. Lippincott Williams and Wilkins, Philadelphia, pp 1033–1049Google Scholar
  6. 6.
    Arnout J (2001) Antiphospholipid syndrome: diagnostic aspects of lupus anticoagulants. Thromb Haemost 86:83–91PubMedGoogle Scholar
  7. 7.
    Tripodi A, Chantarangkul V, Martinelli I, Buciarelli P, Manucci PM (2004) A shortened activated partial thromboplastin time is associated with the risk of venous thromboembolism. Blood 104:3631–3634PubMedCrossRefGoogle Scholar
  8. 8.
    Hron G, Eichinger S, Weltermann A, Quehenberger P, Halbmayer WM, Kyrle PA (2006) Prediction of recurrent venous thromboembolism by the activated partial thromboplastin time. J Thromb Haemost 4:752–756PubMedCrossRefGoogle Scholar
  9. 9.
    Barrowcliffe TW, Gray E (1981) Studies of phospholipid reagents used in coagulation II: factors influencing their sensitivity to heparin. Thromb Haemost 46:634–637PubMedGoogle Scholar
  10. 10.
    Thomson JM, Poller L (1985) The activated partial thromboplastin time. In: Thomson JM (ed) Blood coagulation and haemostasis: a practical guide. Churchill Livingstone, Edinburgh, pp 301–309Google Scholar
  11. 11.
    Olson JD, Arkin CF, Brandt JT (1998) College of American Pathologists Conference XXXI on Laboratory Monitoring on Anticoagulant Therapy: laboratory monitoring of unfractionated heparin therapy. Arch Pathol Lab Med 122:782–798PubMedGoogle Scholar
  12. 12.
    Okuda M, Yamamoto Y (2004) Usefulness of synthetic phospholipid in measurement of activated partial thromboplastin time: a new preparation procedure to reduce batch difference. Clin Lab Haem 26:215–233CrossRefGoogle Scholar
  13. 13.
    Kitchen S, Preston FE (1996) The therapeutic range for heparin therapy: relationship between six activated partial thromboplastin time reagents and two heparin assays. N Engl J Med 75:734–739Google Scholar
  14. 14.
    Manzato F, Mengoni A, Grilenzoni A, Lippi G (1998) Evaluation of the activated partial thromboplastin time (APTT) sensitivity to heparin using 5 commercial reagents: implications for therapeutic monitoring. Clin Chem Lab Med 36:975–980PubMedCrossRefGoogle Scholar
  15. 15.
    Van Cott EM, Laposata M (2001) Coagulation. In: Jacobs DS, DeMott WR, Oxley DK (eds) Laboratory test handbook with key words index. Lexi-Comp, Hudson, pp 327–358Google Scholar
  16. 16.
    Hirsch J, Raschke R (2004) Heparin and low-molecular-weight heparin: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 126:188S–203SCrossRefGoogle Scholar
  17. 17.
    Baker BA, Adelman MD, Smith PA (1997) Inability of the activated partial thromboplastin time to predict heparin levels. Ann Intern Med 157:2475–2479CrossRefGoogle Scholar
  18. 18.
    Brill-Edwards P, Ginsberg JS, Johnston M (1993) Establishing a therapeutic range for heparin therapy. Ann Intern Med 119:104–109PubMedGoogle Scholar
  19. 19.
    Despotis GJ, Summerfield AL, Joist JH, Goodnough LT, Santoro SA, Spitznagel E, Cox JL, Lappas DG (1994) Comparison of activated coagulation time and whole blood heparin measurements with laboratory plasma anti-Xa heparin concentration in patients having cardiac operations. J Thorac Cardiovasc Surg 108:1076–1082PubMedGoogle Scholar
  20. 20.
    Ignjatovic V, Furmedge J, Newall F, Chan A, Berry L, Fong C, Cheng K, Monagle P (2006) Age-related differences in heparin response. Thromb Res 118:741–745PubMedCrossRefGoogle Scholar
  21. 21.
    Ignjatovic V, Summerhayes R, Gan A, Than J, Chan A, Cochrane A, Bennett M, Horton S, Shann F, Lane G, Ross-Smith M, Monagle P (2007) Monitoring unfractionated heparin (UFH) therapy: which anti factor Xa is appropriate? Thromb Res 120:347–351PubMedCrossRefGoogle Scholar
  22. 22.
    Kuhle S, Eulmesekian P, Kavanagh B (2007) Lack of correlation between heparin dose and standard clinical monitoring tests in treatment with unfractionated heparin in critically ill children. Haematologica 92:554–557PubMedCrossRefGoogle Scholar
  23. 23.
    Chan A, Black L, Ing C, Brandao LR, Williams S (2007) Utility of aPTT in monitoring unfractionated heparin in children, Thrombosis Res. 2008;122(1):135–136 Google Scholar
  24. 24.
    Monagle P, Barnes C, Ignjatovic V, Furmedge J, Newall F, Chan A, De Rosa L, Hamilton S, Ragg P, Robinson S, Auldist A, Crock C, Roy N, Rowlands S (2006) Developmental haemostasis: impact for clinical haemostasis laboratories. Thromb Haemost 95:362–372PubMedGoogle Scholar
  25. 25.
    Andrew M, Vegh P, Johnston M, Bowker J, Ofosu F, Mitchell L (1992) Maturation of the hemostatic system during childhood. Blood 80:1998–2005PubMedGoogle Scholar
  26. 26.
    Andrew M, Paes B, Milner R, Jonston M, Mitchell L, Tollefsen D, Powers P (1988) Development of the human coagulation system in the healthy premature infant. Blood 72:1651–1657PubMedGoogle Scholar
  27. 27.
    Andrew M, Paes B, Milner R, Johnston M, Mitchell L, Tollefsen DM, Powers P (1987) Development of the human coagulation system in the full-term infant. Blood 70:165–172PubMedGoogle Scholar
  28. 28.
    Gallisti S, Muntean W, Leschnik B, Myers W (1997) Longer APTT values in healthy children than adults: no single cause. Thromb Res 88:355–359CrossRefGoogle Scholar
  29. 29.
    Legnani C, Mattarozzi S, Cini M, Cosmi B, Favaretto E, Palareti G (2006) Abnormally short activated partial thromboplastin time values are associated with increased risk of recurrence of venous thromboembolism after oral anticoagulation withdrawal. B J Haematol 134:227–232CrossRefGoogle Scholar
  30. 30.
    Despotis GJ, Alsoufiev A, Goodnough LT, Lappas DG (1995) Aprotinin prolongs whole blood activated partial thromboplastin time but not whole blood prothrombin time in patients undergoing cardiac surgery. Anesthesia and Analgesia 81:919–924PubMedGoogle Scholar
  31. 31.
    NCCLS (1998) Collection, transport and processing of blood specimens for coagulation testing and general performance of coagulation assays. In: Standards NCCL (ed) 3rd ed NCCLS, 940 West Valley Road, Wayne, Pennsylvania 19087, USA.Google Scholar
  32. 32.
    Reneke J, Etzell J, Leslie S (1998) Prolonged prothrombin time and activated partial thromboplastin time due to underfilled specimen tubes with 109 mmol/L (3.2%) citrate anticoagulant. Am J Clin Pathol 109:754–757PubMedGoogle Scholar
  33. 33.
    Rose VL, Dermott SC, Murray BF, McIver MM, High KA (1993) Decentralized testing for PT and activated PTT using a dry chemistry portable analyzer. Arch Pathol Lab Med 117:611–617PubMedGoogle Scholar
  34. 34.
    Rondina MT, Markewitz B, Kling S, Nohavec R, Rodgers GM (2007) The accuracy of activated partial thromboplastin times when drawn through a peripherally inserted central catheter. Am J Haematol 82:738–739CrossRefGoogle Scholar

Copyright information

© Humana Press 2013

Authors and Affiliations

  • Vera Ignjatovic
    • 1
    • 2
  1. 1.Haematology Research LaboratoryMurdoch Childrens Research InstituteMelbourneAustralia
  2. 2.Department of PaediatricsThe University of MelbourneMelbourneAustralia

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