Multi-Center Single Arm Trial to Determine The Effectiveness of Warfarin Therapy Duration For Heparin-Induced Thrombocytopenia (HIT)

Inclusion criteria:

- Patient must be able to provide an informed consent

- Patient older than 18 years' old

- Patient with suspected diagnosis of HIT, need 2 of the following:

have a fall in platelet count of > 30% from a baseline prior to heparin/LMWH Platelet
factor 4 (PF4) ELISA positive Develop skin lesions secondary to subcutaneous heparin With T
score more than 4 For those less than 4 we will use serotonin release assay-SRA

- Patient received the bridging therapy of non-heparin anticoagulant

- Patient is receiving the standard of care treatment for HIT

- Patient is willing to be followed up for by one of the physicians listed in the
delegation log

- The Primary physician responsible for the patient is agreeing for the patient to
participate

- Patients are not involved in a clinical trial for HIT management

Exclusion Criteria:

- Patient is unable to sign an informed consent

- Patient doesn't have a confirmed diagnosis of HIT

- Patient Does not have Pulmonary embolus

- Patient does is not on Warfarin for other indications

- Patient is a known case of hypercoagulable disorder

- Patient is not willing to come back for follow up

- Patient is critically ill or has a life expectancy of less than 3 months

- Pregnancy that is in First trimester.

- Multi-system organ failure or estimated survival of less than 30 days

- Uncontrolled hypertension defined as a blood pressure >180/110 mm Hg