The clinicopathological determinants of native arteriovenous fistula failure in patients on maintenance hemodialysis.

BACKGROUND Progressive narrowing of the venous part of dialysis fistulae is caused by hemodynamic and inflammatory factors. OBJECTIVES The pathogenic and clinical determinants of deterioration of the functioning of arteriovenous fistulae in chronically hemodialyzed patients were evaluated. MATERIAL AND METHODS The hemodynamic parameters and the activity of inflammatory growth factors in the vessel wall of newly implanted fistulae were assessed and correlated with the clinical course of 34 hemodialyzed patients. Measurements taken at the time of implanting the fistulae included blood flow in the venous part of the anastomosis and its widest diameter by ultrasound Power Doppler, a histopathologic examination of fistula wall samples and measurements of mRNA expression for growth factors PDGFβ1 and TGFβ in the fistula wall. The results were correlated with clinical data from 36 months' observation: duration of fistula maturation, adequacy of dialysis treatment (eKt/V), the patient's survival, morbidity linked with vascular access problems and general cardiovascular morbidity. RESULTS The mean duration of fistula maturation was 44.9 days (N = 43, SD = 38.6), whereas the average duration of fistula usage as dialysis access was 795.9 ± 480.6 days. Fistula blood flow at the time of implantation, averaged 1782.2 ± 1735.3 ml/min. The mean number of hospitalization days due to vascular access morbidity was 9.9 ± 15.6 days and it correlated positively with the fistula blood flow (R = 0.596, P = 0.004). There was a negative correlation between the expression of PDGFβ1 mRNA and fistula blood flow (R = -0.673, P = 0.011), as well as between TGFβ expression and patient survival (R = -0.722, P = 0.002). CONCLUSIONS Inflammatory activity of the vessel wall growth factors PDGFβ1 and TGFβ implies impairment of fistula function and the patient's cardiovascular morbidity.