Heparin-induced thrombocytopenia and cardiac surgery.
Unfractionated heparin given during cardiopulmonary bypass is remarkably immunogenic, as 25% to 50% of postcardiac surgery patients develop heparin-dependent antibodies during the next 5 to 10 days. Sometimes, these antibodies strongly activate platelets and coagulation, thereby causing the prothrombotic disorder, heparin-induced thrombocytopenia. The risk of heparin-induced thrombocytopenia is 1% to 3% if unfractionated heparin is continued throughout the postoperative period. When cardiac surgery is urgently needed for a patient with acute or subacute heparin-induced thrombocytopenia, options include an alternative anticoagulant (bivalirudin, lepirudin, or danaparoid) or combining unfractionated heparin with a platelet antagonist (epoprostenol or tirofiban). As heparin-induced thrombocytopenia antibodies are transient, unfractionated heparin alone is appropriate in a patient with previous heparin-induced thrombocytopenia whose antibodies have disappeared.
Warkentin
Theodore E
TE
Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada. twarken@mcmaster.ca
Greinacher
Andreas
A
D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use*; D006348:Cardiac Surgical Procedures; D003937:Diagnosis, Differential; D005260:Female; D006493:Heparin / Q000009:adverse effects* / Q000627:therapeutic use; D024764:Hirudin Therapy; D006629:Hirudins / Q000008:administration & dosage / Q000031:analogs & derivatives*; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000008:administration & dosage; D011183:Postoperative Complications / Q000517:prevention & control*; D011994:Recombinant Proteins / Q000008:administration & dosage; D013921:Thrombocytopenia / Q000139:chemically induced* / Q000175:diagnosis / Q000276:immunology / Q000628:therapy; D013927:Thrombosis / Q000517:prevention & control*
D000925:Anticoagulants; D006629:Hirudins; D010446:Peptide Fragments; D011994:Recombinant Proteins; D006493:Heparin