Determinants of native arteriovenous fistula blood flow

Determinants of native arteriovenous fistula (AVF) placement have been well studied. Little is known on whether these factors impact on subsequent blood flow (Qa) in the mature AVF.

Arteriovenous fistula Qa and cardiac index (CI) were determined by ultrasound dilution. Multiple linear regression was used to assess independent predictors of AVF Qa.

Of the 148 patients available for the analysis, 68% were male, with 61% using a radiocephalic AVF. Aetiology of renal disease was: 38% glomerulonephritis (GN), 22% diabetes mellitus (DM), 9% hypertension/ischaemic (HTN) and 31% other. Thirty per cent had coronary artery disease (CAD), 10% cerebrovascular disease and 11% peripheral vascular disease (PVD). Median (iqr) Qa was 1185 mL/min (790-1650) and CI was 3.15 L/min per 1.73 m(2) (2.60-3.93). On univariable analysis, log CI (0.98, P < 0.001), age (-0.1 per 10 years, P = 0.002), access position (upper vs lower 0.26, P = 0.003, PVD (-0.35, P = 0.015), CAD (-0.25, P = 0.008), and primary renal disease (DM vs GN, -0.35, P = 0.003, HTN vs GN, -0.34, P = 0.04) were associated with Qa. On multivariable analysis, CI (0.84, P < 0.001), access position (upper vs lower, 0.17, P = 0.018) and primary renal disease (DM vs GN, -0.26, P = 0.005, and HTN vs GN, -0.26, P = 0.038) remained significant predictors of AVF Qa.

Once established, CI, AVF position and primary renal disease (hypertension/ischaemic and diabetes) are the major determinants of AVF Qa while female gender, CAD, PVD and body mass index were not significant determinants of Qa in this cohort.