Controversies in the management of the haemodialysis-related arteriovenous fistula following kidney transplantation.

Arteriovenous fistula (AVF) is regarded as the best vascular access for chronic haemodialysis (HD). Still, AVF inherently causes significant haemodynamic changes. Although the necessity for vascular access despite its putative cardiovascular complications favours AVF creation in patients under chronic HD, one may question whether sustaining a functional AVF after successful kidney transplantation extends the haemodynamic threat. Small prospective series suggest that AVF ligation causes rapid and sustained reduction in left ventricular hypertrophy. Still, the benefits of such a cardiac remodelling in long-terms of cardiovascular morbi-mortality still need to be proven. Furthermore, the elevation of diastolic blood pressure and arterial stiffness caused by AVF ligation may blunt the expected cardio-protection. Finally, the closure of a functioning AVF may accelerate the decline of kidney graft function. As a whole, the current management of a functioning AVF in kidney transplant recipients remains controversial and does not rely on strong evidence-based data. The individual risk of graft dysfunction and a return to chronic HD also needs to be balanced. Careful pre-operative functional assessments, including cardio-pulmonary testing and estimated glomerular filtration rate slope estimation, may help better selection of who might benefit the most from AVF closure. Large-scale prospective, ideally multi-centric, trials are essentially needed.

The closure of arteriovenous fistula in kidney transplant recipients is associated with an acceleration of kidney function decline.

Background: The creation of arteriovenous fistula (AVF) may retard chronic kidney disease progression in the general population. Conversely, the impact of AVF closure on renal function in kidney transplant recipients (KTRs) remains unknown. Methods: From 2007 to 2013, we retrospectively categorized 285 KTRs into three groups: no AVF (Group 0, n = 90), closed AVF (Group 1, n = 114) and left-open AVF (Group 2, n = 81). AVF closure occurred at 653 ± 441 days after kidney transplantation (KTx), with a thrombosis:ligation ratio of 19:95. Estimated glomerular filtration rate (eGFR) was determined using the Modification of Diet in Renal Disease equation. Linear mixed models calculated the slope and intercept of eGFR decline versus time, starting at 3 months post-KTx, with a median follow-up of 1807 days (95% confidence interval 1665-2028). Results: The eGFR slope was less in Group 1 (-0.081 mL/min/month) compared with Group 0 (-0.183 mL/min/month; P = 0.03) or Group 2 (-0.164 mL/min/month; P = 0.09). Still, the eGFR slope significantly deteriorated after (-0.159 mL/min/month) versus before (0.038 mL/min/month) AVF closure (P = 0.03). Study periods before versus after AVF closure were balanced to a mean of 13.5 and 12.5 months, respectively, with at least 10 observations per patient ( n = 99). Conclusions: In conclusion, a significant acceleration of eGFR decline is observed over the 12 months following the closure of a functioning AVF in KTRs.