Hypercoagulable Workup

When to Test for Hypercoagulability

Thrombosis at unusual sites, such as cerebral, portal, or mesenteric veins, is an indication for testing, as recommended by the American College of Cardiology 1
The American College of Cardiology suggests that testing for hypercoagulable states should be considered in patients with thrombosis at unusual sites, with a moderate level of evidence 2

A complete blood count with differential, including platelet count, should be obtained to screen for myeloproliferative disorders and heparin-induced thrombocytopenia, according to the International Journal of Stroke 3
Coagulation studies, such as PT/INR and aPTT, should be performed as baseline tests and for lupus anticoagulant screening, as recommended by the International Journal of Stroke and Chest 3, 4
Genetic testing for Factor V Leiden mutation and prothrombin G20210A mutation should be considered, with a moderate level of evidence, as suggested by Chest 4

The American College of Cardiology recommends that anticoagulation should not be delayed to obtain testing in acute thrombosis, with a high level of evidence 1
If heparin-induced thrombocytopenia is suspected, the 4T score should be calculated immediately, with a moderate level of evidence, as recommended by Blood advances 5, 6, 7

For antiphospholipid syndrome, moderate-intensity warfarin (INR 2.0-3.0) is recommended over high-intensity (INR 3.0-4.5) for both arterial and venous thromboembolism, with a moderate level of evidence, as suggested by Chest 4

The American College of Cardiology advises against delaying anticoagulation to obtain testing in acute thrombosis, with a high level of evidence 1
The American College of Cardiology recommends against interpreting protein C, protein S, or antithrombin levels while the patient is on warfarin or heparin, with a moderate level of evidence 1

Recurrent unprovoked venous thromboembolism (VTE) is an indication for testing, with a recommendation for indefinite anticoagulation in patients with a history of two or more episodes, as suggested by the American Society of Hematology 8

The American College of Chest Physicians recommends testing for lupus anticoagulant panel, anticardiolipin antibodies, and anti-beta-2-glycoprotein I antibodies before anticoagulation, with a strength of evidence grade of 1B 9
Genetic testing for factor V Leiden mutation and prothrombin G20210A mutation can be done at any time, as these tests are not affected by anticoagulation, according to the American College of Chest Physicians 9

The American Heart Association recommends calculating the 4T score immediately if platelet count drops >50% or thrombocytopenia develops 5-14 days after heparin exposure, with a recommendation to stop all heparin products and switch to a non-heparin anticoagulant if the score is ≥4 10

The American College of Chest Physicians recommends using moderate-intensity warfarin (INR 2.0-3.0) for both arterial and venous thromboembolism in patients with antiphospholipid syndrome, with a strength of evidence grade of 1B 9
The European Society of Cardiology recommends direct oral anticoagulants (DOACs) over warfarin for most VTE patients, unless contraindicated, with a class I recommendation 11

The American College of Cardiology recommends low molecular weight heparin (LMWH) over warfarin in pregnant patients, due to the teratogenic effects of warfarin, with a class I recommendation 10
The National Comprehensive Cancer Network recommends LMWH or DOACs over warfarin for cancer-associated thrombosis, with a category 1 recommendation 12