Cardiac surgery in acute heparin-induced thrombocytopenia managed with therapeutic plasma exchange and intravenous immunoglobulin

Background: Urgent surgery requiring heparin exposure during cardiopulmonary bypass can be challenging in patients with acute heparin-induced thrombocytopenia (HIT). The use of treatments such as therapeutic plasma exchange (TPE) to remove HIT antibodies and intravenous immunoglobulin (IVIg) to antagonize HIT antibodymediated platelet activation are increasingly reported in patients who undergo cardiac surgery. The optimal treatment approach to mitigate the risks of heparin administration in this situation is not known. Key Clinical Question: Can TPE coupled to IVIg allow for safe heparin exposure in patients with HIT? Clinical Approach: TPE and IVIg were used to enable heparin exposure for surgical placement of a left ventricular assist device in a patient with HIT. Serial patient samples were tested in antigen-based and functional HIT assays. Conclusion: Dissociation between antigen-based (enzyme-linked immunosorbent assay) and functional (serotonin release assay) testing was noted, and TPE coupled to IVIg was associated with an excellent clinical response.