PURPOSE:To assess the dynamic of various health-related quality of life (HRQoL) parameters 3 years after pulmonary thromboendarterectomy (PTE), and to identify factors affecting HRQoL parameters in patients with chronic thromboembolic pulmonary hypertension (CTEPH) in the long-term follow-up after surgery. METHODS:This prospective cohort study included 128 patients with CTEPH before and after the PTE (3 year follow-up). The HRQoL was examined using the Short-Form 36 Health Survey Questionnaire (SF-36). RESULTS:In patients with CTEPH 3 years after PTE, a significant improvement in all the HRQoL parameters. The summary indicators of the physical and mental components of health remained at the same level as 1 year after the PTE and did not exceed 50 points. The residual pulmonary hypertension was a leading factor limiting parameters of physical and mental health 3 years after a PTE. In addition, the parameters of physical activity were adversely affected by age and the age-adjusted Charlson Comorbidity Index. CONCLUSIONS:In the study group of patients with CTEPH, PTE contributes to a significant improvement in all HRQoL parameters, which observed both 1 year and 3 years after surgery. The leading factor adversely affecting the physical and emotional components of health in the long-term period after PTE was residual pulmonary hypertension recorded in the early postoperative period. In addition, some physical HRQoL parameters are affected by age and age-adjusted Charlson Comorbidity Index.