Recombinant hirudin anticoagulation for aortic valve replacement in heparin-induced thrombocytopenia

Purpose: To report the case of a patient with HIT that received a prolonged infusion of r-hirudin (lepirudin; Refludan(R); Hoechst, France) before, du ring and after cardiopulmonary bypass (CPB) for aortic surgery. Although ad ministration of r-hirudin for CPB anticoagulation has previously been repor ted, many questions persist concerning the best therapeutic regimen for CPB anticoagulation as well as the time of onset and the doses for post-operat ive anticoagulation. Clinical Features: A 65-yr-old man was admitted for surgery of aortic steno sis after an episode of acute pulmonary edema complicated by deep venous th rombosis in the context of documented HIT. The patient received r-hirudin f or 13 dy before surgery at doses (0.4 mg.kg(-1) bolus followed by 0.15 mg.k g(-1).hr(-1) continuous infusion) that maintained activated partial thrombo plastin time (aPTT) ratios between 2 and 2.5. Anticoagulation for CPB was p erformed with r-hirudin given as 0.1 mg.kg(-1) iv bolus and 0.2 mg.kg(-1) i n the CPB priming volume. Anticoagulation during CPB was monitored with the whole blood activated coagulation time and ecarin clotting time (ECT) perf ormed in the operating room with values corresponding to r-hirudin concentr ations > 5 mu g.ml(-1) during CPB. Anticoagulation during CPB was uneventfu l. Two bleeding episodes, related to the r-hirudin regimen and necessitatin g allogeneic blood transfusion, occurred after surgery. Conclusion: This case report confirms previous experience of the use of r-h irudin for anticoagulation during CPB and provides additional information i n the context of prolonged r-hirudin infusion before and after CPB.