APTT, or Activated Partial Thromboplastin Time measures the speed at which blood clots in the body are formed, through a route known as the intrinsic pathway.
What might a low result mean?
Decreased aPTT may be seen temporarily during the body's response to acute trauma or inflammation.
What might a high result mean?
Prolonged aPTT means that blood clots in the body take longer to form. Conditions with higher values for aPTT include clotting factor deficiencies, antiphospholipid syndrome and haemophilia.
Medications such as heparin can also increase aPTT.