The clinical picture, differential diagnosis and prognosis in chronic thromboembolic pulmonary hypertension (CTEPH) is being discussed on the basis of a dozen of the authors' cases. The clinical course of CTEPH in 2 patients fulfilling the main criterium for pulmonary thromboendarterectomy and undergoing one year anticoagulation is examined. As a result patient with one large pulmonary vessel occlusion (a. lobaris superior sinistra) improved his clinical status as well as hemodynamic and echocardiographic outcome. In patient with multivessel pulmonary occlusion gradual clinical aggravation and hemodynamic-echocardiographic progression of CTEPH was observed.