Early Changes in Macrocirculation Precede Microcirculatory Adaptation After Kidney Transplantation

Background: Renal transplantation is the treatment of choice for patients with end-stage kidney disease, as it is associated with reduced cardiovascular morbidity and mortality compared to chronic dialysis. The aim of our study was to analyze short-term changes in various parameters of large artery compliance and microcirculation following renal transplantation. Methods: All patients underwent vascular examination both before and 8 weeks after renal transplantation. Vascular function and structure in the macrocirculation were assessed using parameters such as central pulse pressure, augmentation index, and pulse wave velocity, measured with the SphygmoCor XCEL System. Retinal capillary flow, wall-to-lumen ratio, vessel and lumen diameter, wall thickness of retinal arterioles—reflecting microcirculatory parameters—were evaluated using Scanning Laser Doppler Flowmetry (SLDF). Results: Forty-two patients with end-stage kidney disease (mean age 44.5 ± 14.8 years) were followed for 2 months after renal transplantation. Estimated GFR at 2 months post-transplant was 49.3 ± 15.2 ml/min/1.73 m2. Pulse wave velocity, central pulse pressure, and central systolic pressure decreased significantly following transplantation, in parallel with reductions in office systolic (p<0.001) and diastolic blood pressure (p=0.003). No significant changes were observed in microcirculatory parameters (table 1). Conclusion: Our data indicate that large artery compliance (Windkessel function) improves after renal transplantation potentially explaining, at least in part, the reduced cardiovascular morbidity observed after renal transplantation compared to remaining on chronic dialysis.