ATYPICAL HEPARIN-INDUCED THROMBOCYTOPENIA COMPLICATED BY INTRACARDIACTHROMBUS, EFFECTIVELY TREATED WITH ULTRA-LOW-DOSE RT-PA LYSIS AND RECOMBINANT HIRUDIN (LEPIRUDIN)

A serious retroperitoneal bleeding occurred in a 56-year-old male pati ent receiving unfractionated heparin due to multiple pulmonary embolis m. After reducing the heparin dose, the patient developed a new pulmon ary embolism and a large thrombus in the right atrium. Concomitantly, the platelet count dropped to a value of 29 g/l. Heparin-induced throm bocytopenia (HIT) was confirmed by a functional assay, the heparin-ind uced platelet activation (HIPA) assay, whereas the results of a platel et factor 4/heparin complex ELISA were repeatedly negative. This indic ated that the patient's HIT antibodies were directed towards an antige n other than platelet factor 4/heparin complexes. For treatment of the atrial thrombus, an ultra-low-dose lysis with rt-PA (2 mg/h, intraven ously) was administered for a period of 52 h, overlapping with systemi c treatment with recombinant hirudin (Lepirudin, Refludan(R), 0.06-0.1 4 mg/kg/h intravenously). The aim was to enhance lysis of the thrombus without increasing the haematoma, and at the same time keep the risk of fulminant pulmonary embolism due to thrombus fragmentation as low a s possible. The cardiac thrombus disappeared within 48 h, without nerv signs of pulmonary embolism. Platelet counts normalized within nine d ays. Blood Coag Fibrinol 9:273-277 (C) 1998 Lippincott-Raven Publisher s.