1.3 Impact of Renal Transplantation on Arterial Stiffness

Abstract

Introduction

Risk of a cardiovascular event is known to increase in the period immediately post-transplantation before returning to baseline or lower. We hypothesised that this might be due to changes in arterial stiffness and/or endothelial function.

Methods:

We measured aortic pulse wave velocity (aPWV), wave reflections (AIx), and endothelial function in 40 patients undergoing living donor renal transplantation, immediately pre-transplant and at 1 week, 3 and 12 months post-transplant.

Results:

35 patients completed the 12 months follow-up. Mean eGFR increased from 8±3 mL/min pre-transplant to 51 ±13 mL/min at 1 week post-transplant (P < 0.001) and remained at this level throughout follow-up. aPWV increased from 7.4±1.4m/s at baseline to 8.1 ±1.3m/s at 1 week post-transplant (P<0.05), but returned to baseline levels after 12 months. A similar trend in mean pressure was observed. AIx was unchanged over the 12 months. Brachial flow mediated dilatation (FMD) was unchanged at 1 week post-transplant but had improved slightly, though significantly at 1 year (4.73 ±3.76%vs.6.72 ±3.22%,P< 0.05).The response to GTN was not altered. In a subset of patients who had plasmapharesis pre and post-transplant, AIx was significantly increased from baseline after 1 year (8.4±11.4%vs.26.3 ±11.4%, P<0.03). Brachial response to GTN was also significantly improved (2.0±1.8%vs.9.2±4.1%, P = 0.009), although FMD was unchanged.

Conclusion:

Arterial stiffness is increased at 1 week post-transplant and returns to baseline by one year reflecting the known changes in cardiovascular risk. Endothelial function appears to improve in the longer term. Therapeutic strategies targeted at minimising arterial dysfunction around the time of transplantation may improve outcomes.