From the Guidelines
For patients admitted with stroke, the recommended hypercoagulable labs include complete blood count, prothrombin time/INR, activated partial thromboplastin time, as per the guidelines from the American Heart Association/American Stroke Association 1. These tests are essential for evaluating the patient's coagulation status and identifying potential underlying thrombophilias that may have contributed to the stroke. The rationale for this workup is to guide secondary prevention strategies and determine optimal anticoagulation duration, particularly in younger patients (<50 years), those with recurrent events, family history of thrombosis, or strokes without traditional risk factors. Additionally, tests for inherited or acquired hypercoagulable state may be considered as clinically indicated to identify contributors to or relevant risk factors for stroke, as suggested by the 2021 guideline for the prevention of stroke in patients with stroke and transient ischemic attack 1. It is also important to note that the 2023 systematic review and synthesis of global stroke guidelines recommends blood work, including complete blood count, prothrombin time, partial thromboplastin time, glucose, HbA1c, creatinine, and fasting or non-fasting lipid profile, in patients with ischemic stroke or TIA 1. However, the most recent and highest quality study, the 2023 systematic review, does not provide a comprehensive list of hypercoagulable labs, but it emphasizes the importance of blood work in the diagnostic evaluation of stroke patients. Therefore, the recommended hypercoagulable labs should be based on the most recent guidelines and should include, at a minimum, complete blood count, prothrombin time/INR, and activated partial thromboplastin time, as well as other tests as clinically indicated. Some key points to consider when ordering these labs include:
- Timing is important, as acute phase reactants can alter protein levels immediately after stroke
- For patients already on anticoagulation, specialized testing coordination with hematology may be necessary
- Results should be interpreted in clinical context, as transient abnormalities can occur during acute illness
- The choice of labs may vary depending on the individual patient's clinical presentation and risk factors.
From the Research
Hypercoagulable Labs for Stroke
The following hypercoagulable labs can be done on an inpatient basis for stroke:
- Protein C deficiency 2, 3, 4, 5
- Protein S deficiency 2, 3, 4, 5
- Antithrombin III deficiency 2, 3, 4, 5
- Activated protein C resistance (APCR)/factor V Leiden mutation (FVL) 2, 3, 5
- Anticardiolipin antibodies (ACL) 2
- Lupus anticoagulant (LA) 2
- Prothrombin mutation 2, 5
- Factor II 5
Rationale for Testing
These tests are recommended because they can help identify underlying hypercoagulable states that may have contributed to the stroke 2, 3, 4, 5. The results of these tests can inform treatment decisions and may help prevent future strokes 2, 5.
Patient Selection
The decision to order these tests should be based on the patient's clinical presentation and history 2, 3, 5. Patients with a history of recurrent strokes, family history of thrombophilia, or other risk factors for hypercoagulable states may be more likely to benefit from these tests 2, 3, 5.