Chronic thromboembolic pulmonary hypertension (CTEPH) can be defined as pulmonary hypertension with persistent pulmonary perfusion defects causes by unresolved thrombi. All symptomatic CTEPH patients with documented pulmonary vascular resistance > 300 dyn*sec*cm(-5) and proximal lesions should be considered for surgical treatment--pulmonary endarterectomy. The role of pharmacological treatment remains controversial and should be restricted to inoperable cases and persistent pulmonary hypertension after pulmonary endarterectomy. Every year about 30 procedures is performed in two specialised centers in Poland with 1 year mortality at 8-9%. Number of procedures done gives the frequency of pulmonary endarterectomy at 0.7/million of population/year. Current data from UK indicate the actual ratio of surgical treatment of CTPH at 2/million/year. The article discusses reasons for CTEPH is underdiagnosed and why rate of surgical therapy in Poland is too low.