Reversal of arterial stiffness and maladaptative arterial remodeling after kidney transplantation

Background--Chronic kidney disease is characterized by stiffening, thinning, dilatation, and increased circumferential wall stress of large arteries, associated with increased cardiovascular risk. Kidney transplantation (KT) reverses many pathological features of chronic kidney disease and improves life expectancy; however, longitudinal studies exploring the impact of KT on recipient large arteries are scarce. Methods and Results--This study was designed to appraise arterial changes following KT. Carotid-femoral pulse wave velocity, carotid remodeling (circumferential wall stress and carotid internal diameter), and stiffness were measured in 161 consecutive recipients receiving either a living (n = 49) or a deceased (n = 112) donor allograft, at 3 and 12 months after transplantation. Mean pulse wave velocity decreased from 10.8 m/s (95% confidence interval, 10.5-11.2 m/s) (at month 3) to 10.1 m/s (95% confidence interval, 9.8-10.5 m/s) (at month 12) (P < 0.001). After multivariate adjustment, pulse wave velocity reduction from month 3 to month 12 was significantly larger in the living donor allograft KT (P < 0.001). Circumferential wall stress decreased, 70 kPa (95% confidence interval, 68-72 kPa) to 64 kPa (95% confidence interval, 62-67 kPa), as well as carotid internal diameter and carotid stiffness (P < 0.001 for all). Reductions in circumferential wall stress, diameter, and stiffness were significantly larger in the living donor allograft KT (P < 0.001). When deceased donor allograft patients were classified into standard and expanded criteria donors, changes in both pulse wave velocity and circumferential wall stress were blunted in expanded criteria donors. Changes were independent of graft function and blood pressure changes. Conclusions--Large-artery stiffness and maladaptive carotid artery remodeling of chronic kidney disease is partially reversed within 12 months of KT and appears unrelated to renal function. Improvements were independently associated with live organ donation. Our data suggest that expanded criteria donors may hamper vascular recovery.