The role of hemodynamics in arteriovenous fistula remodelling and failure. A CFD longitudinal study

The mechanism of vascular stenosis development in haemodialysis arteriovenous fistula is still mostly unknown. Almost all computational fluid dynamics (CFD) studies are performed at given time after surgery, but evolution of fistula remodelling and failure has not been studied so far. We then performed a longitudinal study on morphological and hemodynamic changes in an arteriovenous fistula that showed progressive stenosis and failure 1.5 years after surgery. The comparison of CFD and morphological changes showed that vascular wall remodelling acted as a protecting response, with progressive expansion of the stenosis in the venous outflow tract that induced regularization of velocity waveforms and decreased the disturbed flow metrics.