This present study explains chronic thromboemboli pulmonary hypertension in a patient with eisenmenger syndrome and large patent ductus arteries. Chronic thromboemboli pulmonary hypertension (CTEPH) is group 4 of pulmonary hypertension, related to a clot blocking in the pulmonary arteries in the lungs. 51 years old female admitted for dyspnea, cyanotic, a decrease of excirse capacity, cough, limb edema, and right chest pain for several days. The patient was treated with ARB, Diuretic, anticoagulant, CPAP Antibiotic. In this case, we can see some early criteria suggesting pulmonary artery obstruction in clinical like: dyspnea, cyanotic, suddenly abrupt spO2 to 50%, ECG with RBBB and RV hypertrophy criteria that make us concern and decide to do more non-invasive imaging procedure to diagnose. There are many congenital heart diseases patients cannot be detected soon after birth because of poor condition and the lack of equipment and good training cardiologists to diagnose but we are trying to do better for patients day by day in Gia Lai Viet Nam.