Background: The determination of clinical aspects and diagnosis value of echocardiography at patients with pulmonary hypertension (PH) secondary congenital systemic-to-pulmonary shunts and chronic heart failure (CHF). Material and methods: Considering echocardiography one of the most informative, non invasive method of diagnostics of a PH, given research has included 128 children (69 girls and 59 boys) pulmonary hypertension caused by congenital systemic- to- pulmonary shunts, with the age between 1 month and 17 years. The comparing group has been constituted of 38 children with diverse congenital heart diseases and CHF but without PH. Has been determined the diameter of pulmonary artery at its trunk and its right branch, right atrial (RA), the thickness of the free wall of right ventricle (RV), the diameter of the fibrous ring of the tricuspid valve, the pressure of pulmonary artery, PVR, TAPSE and Tei index of RV. Results: The clinical symptoms at patients with PH are: breathlessness (100%), fatigue (92,2%), weakness (75,78%), angina (37,5%), syncope (29,7%) and abdominal distension (56,25%). Pressure in a pulmonary artery and consequences of a PH on rebuild cardiovascular system were certain: dilation the right departments of heart (RA in 84,5%, RV in 92 %), hypertrophy RV (5-9,2 mm) and global dysfunction RV (TAPSE<20mm, high Tei index of RV). Results of research have allowed to define degrees of haemodynamic infringements at patients with a PH. Have been identified the echocardiography parameters with the bad prognosis at a pulmonary hypertension against congenital heart diseases. Conclusions: Echocardiography is one of the most informative, non invasive method of diagnostics, of a pulmonary hypertension caused by congenital systemic - to- pulmonary shunts. The results of research identified the echocardiography parameters with the bad prognosis at a pulmonary hypertension against congenital heart diseases: dilation RA and RV, TI degree, dilatation of PA trunk, high value of PAPm and sistolic squeeze IVS.