Vascular access for hemodialysis is crucial for appropriate course of the treatment as well as for good prognosis for patients with chronic renal insufficiency. In this paper we present the case of chronically hemodialysed patient who developed high-output cardiac failure after several days before creation of the upper arm brachio-cephalic arteriovenous fistula. Ultrasonographic imaging of the fistula showed an over-functioning anastomosis with flow reaching 41/min. The surgical correction of the anastomosis length to 4 mm and reduction of the cephalic vein diameter to 5 mm, significantly improved general status of the patient, simultaneously maintaining an accurate function of the fistula, with the maximal flow up to 850 ml/min.