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Activated Clotting Time

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Also known as: ACT; Activated Coagulation Time
Formal name: Activated Clotting Time

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At a Glance

Why Get Tested?

To monitor treatment with heparin or other blood-thinning medications (anticoagulants) when undergoing heart bypass surgery, coronary angioplasty, or dialysis

When to Get Tested?

When you are receiving high doses of heparin to prevent clotting during surgical procedures such as a heart bypass; when heparin levels are too high to allow monitoring with a PTT and/or when a rapid result is necessary to monitor treatment

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?