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PTT

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Also known as: Activated Partial Thromboplastin Time; aPTT; APTT
Formal name: Partial Thromboplastin Time

At a Glance

Why Get Tested?

As part of an investigation of a possible bleeding disorder or blood clot (thrombotic episode); to monitor unfractionated (standard) heparin anticoagulant therapy; as part of screening before surgery or other invasive procedure

When to Get Tested?

When you have unexplained bleeding, inappropriate blood cloting, or recurrent miscarriages; when you are on standard heparin anticoagulant therapy; sometimes as part of a pre-surgical screen

Sample Required?

A blood sample drawn by needle from a vein in your arm

Test Preparation Needed?

None