Plasma-modified ACT can be used to monitor bivalirudin (Angiomax) anticoagulation for on-pump cardiopulmonary bypass surgery in a patient with heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a problem of growing significance and concern, affecting an estimated 1-3% of patients among those receiving an estimated 10 million heparin exposures annually in the United States. The prevalence of heparin antibodies has been reported as at least 12.7% in the general cardiac surgery population before surgery and 42% following surgery.