[A case of chronic thromboembolic pulmonary hypertension based on essential thrombocythemia].

We report a case of chronic thromboembolic pulmonary hypertension based on essential thrombocythemia. A 72-year-old woman was admitted to our hospital with dyspnea. The hematologic workup revealed a platelet count of 99.2 x 10(4)/microliter. Chest radiographic examination revealed cardiomegaly with bilateral pulmonary artery enlargement. A perfusion lung scan suggested and pulmonary angiography confirmed--multiple pulmonary embolism. Pulmonary artery pressure was 90/30 (51) mmHg. Thrombolytic therapy was performed successfully, and a diagnosis of essential thrombocythemia was made on the basis of the criteria proposed by the Polycythemia Vera Study Group. The therapy of essential thrombocythemia including ranimustine was effective, and one year later, the essential thrombocythemia and chronic respiratory failure had improved. To our knowledge, this case of chronic thromboembolic pulmonary hypertension based on essential thrombocythemia is a very rare one.