Bivalirudin for patients with heparin-induced thrombocytopenia undergoing cardiovascular surgery

OBJECTIVE: To evaluate the use of bivalirudin in patients with heparin-induced thrombocytopenia (HIT) undergoing cardiovascular surgery. DATA SOURCES: Relevant information was identified through a search of MEDLINE (1966-April 2008), International Pharmaceutical Abstracts (1960-April 2008), and Cochrane Databases (publications archived until April 2008) using the terms bivalirudin, heparin-induced thrombocytopenia, and cardiovascular surgery. STUDY SELECTION AND DATA EXTRACTION: Prospective and retrospective studies, case reports, and case series in adults were eligible for inclusion if bivalirudin had been used in a patient with known HIT undergoing any cardiovascular surgical procedure other than percutaneous coronary intervention. DATA SYNTHESIS: Two small, open-label, multicenter clinical trials were identified that evaluated treatment with bivalirudin in patients with HIT undergoing coronary artery bypass graft surgery. One looked at on-pump cardiopulmonary bypass (CPB), while the other looked at off-pump CPB. Procedural success was achieved at day 7 in 94% (n = 46) of patients in the on-pump CPB study and in 92% (n = 47) of patients in the off-pump CPB study. Dosing strategies varied between the 2 trials, with the on-pump study using a 1-mg/kg bivalirudin bolus followed by a 2.5-mg/kg/h infusion; the off-pump study used a 0.75-mg/kg bolus followed by a 1.75-mg/kg/h infusion. In addition, 10 case reports met the criteria to be included in the review and are summarized. In these cases, procedural success was reported using various bivalirudin doses in valve repair and replacement, right ventricular assist device implantation, and heart transplantation. CONCLUSIONS: Growing data demonstrate procedural success with bivalirudin in patients with HIT undergoing cardiovascular surgery. However, bivalirudin dosing and goal-activated clotting times varied between the studies and case reports. Bivalirudin represents a viable alternative to heparin in patients with HIT undergoing cardiovascular surgery; however, further trials are warranted to identify optimal dosing and monitoring parameters.