Epidemiology of chronic thromboembolic pulmonary hypertension in Korea: Results from the Korean registry

Background/Aims: The diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) is difficult for numerous reasons and is related with a poor prognosis. In Korea, the incidence of CTEPH and its clinical features are unknown. Thus, in this study, we evaluated the clinical characteristics and outcomes of CTEPH in a Korean cohort. Methods: This study included South Korean patients diagnosed with CTEPH between September 2008 and October 2011. Baseline characteristics, treatments and outcomes were analyzed. Results: A total of 134 patients were included in this study with 76 females (56.7%). Their median age was 58.3 ± 15.9 years and dyspnea (112 patients, 83.5%) was the most common presenting symptom. Sixty-three patients (47%) had a history of acute pulmonary embolism or deep vein thrombosis, and six (4.5%) had pulmonary tuberculosis. In total, 28 patients (21%) underwent pulmonary thromboendarterectomy (PTE), and 99 patients had medical therapy. During the study period, 18 patients (13.4%) died. In a multivariate analysis, higher hemoglobin (relative risk [RR], 1.516; 95% confidence interval [CI], 1.053 to 2.184; p = 0.025) and lower total cholesterol levels (RR, 0.982; 95% CI, 0.965 to 0.999; p = 0.037) were associated with increased mortality. Conclusions: This was the first national cohort study of Korean patients with CTEPH. Accurate diagnosis, characterization and distributions of CTEPH are imperative for prompt treatment in patients, particularly those undergoing PTE.