A case of 68 years old women suffering from chronic anemia, myelodysplastic syndrome and treated with progestogen due to endometrial hypertrophy is presented. Initially she was admitted to a regional hospital because of progressive weakness and exertional dyspnea. Three months earlier she reported an episode of acute dyspnea and chest pain. On the basis of clinical symptoms and perfusion lung scintigraphy pulmonary embolism (PE) was diagnosed. Patient received i.v. heparin which was changed to s.c. nadroparine subcutaneously. Platelet count dropped to 55,000'/ml on fifth day of treatment from initial level of about 200,000'/ml. Heparin induced thrombocytopenia was diagnosed, heparin was stopped and ticlopidine was recommended. After 3 weeks symptoms suggesting recurrent PE were observed. The patient was transferred to National Tuberculosis and Lung Diseases Research Institute. Recombinant hirudine (Refludan) was administrated (bolus 0.4 mg/kg and initial dose of infusion 0.1 mg/kg/h) overlapping with acenocoumarol from second day. Dose of r-hirudine was adjusted to achieve APTT prolongation 1.5 to 2.5 times of mid-normal range. During treatment with r-hirudine no bleeding and new thromboembolic complications occurred. Platelets count remained within normal range. After 14 days clinical improvement was observed, though symptoms of right ventricular overload and hypoxemia were still present after 6 months of treatment with oral anticoagulants suggesting chronic thromboembolic pulmonary hypertension.