Central aortic pressure augmentation in stable renal transplant recipients

Premature cardiovascular disease is the leading cause of death in renal transplant recipients and classical risk factors significantly underestimate the risk. The increased effect of arterial wave reflections on central arteries has recently been shown to be an important independent predictor of cardiovascular mortality in chronic hemodialysis patients. The aim of this study was to assess the contribution of several classical and potential non-classical cardiovascular risk factors on aortic pressure augmentation by the reflected arterial wave in stable renal transplant recipients.

Using the non-invasive technique of pulse wave analysis aortic augmentation was investigated in 250 stable renal transplant recipients. Peripheral pulse waveforms were recorded from the radial artery. Central aortic waveforms were then generated and the aortic augmentation index calculated.

In multivariate analysis, female sex (regression coefficient 7.5 +/- 1.7%; P < 0.001), heart rate (-4.8 +/- 0.5% per 10 beats/min; P < 0.001), mean arterial pressure (4.2 +/- 0.6% per 10 mm Hg; P < 0.001), the persistence of an arteriovenous fistula (4.1 +/- 1.3%; P < 0.005), total time on renal replacement therapy (3.8 +/- 0.9% per 10 years; P < 0.001), height (-3.1 +/- 0.8% per 10 cm; P < 0.001), immunosuppression with cyclosporine (2.8 +/- 1.3%; P < 0.005) and age (2.5 +/- 0.5% per 10 years; P < 0.001) were all important correlates of aortic augmentation index.

Our findings suggest, to our knowledge for the first time, that both the presence of a functioning arteriovenous fistula and immunosuppressive treatment with cyclosporine are associated with an increased aortic augmentation index in renal transplant recipients and could, therefore, be potential reversible contributors to the high cardiovascular risk profile in these patients.