Present studies reveal that endothelial dysfunction depends on balance of the factors of vessels homeostasis. The author shows that endothelin-1 is a marker of the endothelial dysfunction and of the heart failure: its level is low in the serum of newborn infants with congenital heart diseases both with increased and decreased pulmonary circulation. Significant increasing of endothelin-1 concentration in 2-month old infants with pulmonary hypertension is noted. On the other hand, patients of the same age with poor pulmonary circulation are characterized by low concentration of endothelin-1 in the serum.
