A 10-year-old child has been folowed-up for the dilated cardiomyopathy. The child presents with dyspnea, cardialgia. There are dense, nonmobile edemata on the lower extremities and sacrum. Ps- 120/min. The cardiac borders are extended transversely. Heart sounds are muffled, there is blowing systolic murmur at the apex and over the xiphoid process. Liver is 3 cm enlarged, urine output is reduced. The blood total protein - 58.6 g/l. In urine: protein - 0,025 g/l, WBCs - 2-4 in the field of vision, RBCs - 2-3 in the field of vision. What is the main mechanism of edema syndrome development: