Partial Thromboplastin Time, Activated
This test is used in the evaluation of people who have unexplained bleeding or inappropriate clot formation, as well as to monitor the levels of blood thinner medication.
The partial thromboplastin time is a test that is done on a persons blood to determine the adequacy with which they are able to clot their blood. This test, along with the prothrombin time test, provides an evaluation of the ability to clot blood in people who are on blood-thinning medication such as warfarin. This test is used in the evaluation of people who have unexplained bleeding or inappropriate clot formation, as well as to monitor the levels of warfarin in order to determine warfarin toxicity. This test can also be used to help in the diagnosis of antiphospholipid syndrome.
This test is performed in following conditions such as:
• Unexplained bleeding or easy bruising
• Bleeding gums
• A blood clot in a vein or artery
• An acute condition such as disseminated intravascular coagulation (DIC)
• A chronic condition such as severe liver disease that may affect hemostasis
• People on warfarin or other anticoagulation medication
Also Known As: PTT, aPTT
If Heparin is being administered by intermittent injection, specimen should be drawn 1 hour prior to next dosage. This test is not appropriate for monitoring Unfractionated Heparin therapy. If you are taking Heparin, please consult your doctor to determine if this test is appropriate.
Estimated Time Taken
Turnaround time for the PTT test is typically 1 business day.