Prospective Study of Changes in Arterial Stiffness among Kidney-Transplanted Patients

Rate of Ipsilateral Chronic Limb-Threatening Ischemia (CLTI) After Kidney Transplantation: A Retrospective Single-Center Study

Objective: To analyze whether the rate of lower extremity (LE) ischemia is higher on the ipsilateral side after kidney transplantation.

Methods: Our institutional transplant database was retrospectively queried for all patients who received a kidney transplant and underwent subsequent LE revascularization or major limb amputations between January 2004 and July 2020. The one-sample binomial test was used to test whether the LE ipsilateral to the transplanted kidney was at higher risk of peripheral arterial disease (PAD) complications necessitating intervention (major amputation or revascularization).

Results: There were 1,964 patients who received a kidney transplant during the study period. Of these, 51 patients (3%) had subsequent LE arterial revascularizations or major amputations. The mean age was 58 ± 10 years, and 37 patients (73%) were male. A total of 33 patients had ipsilateral LE vascular interventions (26 major amputations and seven revascularizations) while 18 patients had contralateral vascular interventions (14 major amputations and four revascularizations) (P = 0.049). The average interval between transplantation and subsequent vascular intervention was 52 months for the ipsilateral intervention group and 41 months for the contralateral intervention group (P = 0.33).

Conclusions: In patients who received kidney transplantation and required subsequent LE surgical intervention, we observed an association between the side of transplantation and the risk of future ipsilateral LE arterial insufficiency. Further studies are needed to determine the etiology of this association.

Kidney transplantation improves arterial stiffness in patients with end-stage renal disease

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of mortality among the patients with end-stage renal disease (ESRD). Arterial stiffness is a well-accepted predictor of cardiovascular mortality in general population and ESRD patients. The aim of this study was to compare the change of arterial stiffness in kidney transplant recipients (KTRs) and ESRD patients, and further investigate the impact of kidney transplantation (KT) on arterial stiffness.

METHODS

A total of 138 maintenance hemodialysis patients, 198 KTRs and 75 healthy volunteers were enrolled in this study. The carotid-femoral pulse wave velocity (CF-PWV) and carotid-radial PWV (CR-PWV) were determined, and the correlations of PWV with biochemical parameters were analyzed.

RESULTS

CF-PWV was highest in the maintenance hemodialysis patients, but similar between KTRs and healthy volunteers. Bivariate correlation analysis among KTRs demonstrated that CF-PWV was positively correlated with high level of peripheral diastolic blood pressure, pulse pressure, mean artery pressure, BUN and HDL, but negatively correlated with albumin. Univariate polytomous logistic regression analysis showed that age, BMI, systolic blood pressure, pulse pressure, length of KT and BUN were associated with the increase of CF-PWV value.

CONCLUSIONS

Aortic stiffness could be improved after KT. Meanwhile, age, BMI, systolic blood pressure, pulse pressure, length of KT and BUN were independent predictors of the increase of CF-PWV in KTRs.

Arterial stiffness in end-stage renal disease-pathogenesis, clinical epidemiology, and therapeutic potentials

Arterial stiffness is an important risk factor for cardiovascular morbidity and mortality in patients with end-stage renal disease (ESRD). Arterial stiffness aggravates cardiovascular risk via multiple pathways, such as augmentation of aortic systolic pressure, subendocardial hypoperfusion, and excess pulsatile energy transmission from macro- to microcirculation. Pathogenesis of the arteriosclerotic process in ESRD is complex and not yet fully understood. Several factors unique to ESRD, such as mineral metabolism disturbances, vascular calcifications, formation of advanced glycation end-products, and acute and chronic volume overload, are proposed to play a particular role in the progression of arteriosclerosis in ESRD. As these and other mechanistic pathways of arterial stiffening in ESRD are elucidated, there is hope that this knowledge will be translated into novel therapeutic interventions targeting arterial stiffness. In the meantime, blood pressure (BP) lowering via strict volume control and appropriate use of antihypertensive drugs is a fundamental step in reversing accelerated arterial stiffening and modifying the cardiovascular risk profile of ESRD patients. In this article, we review the pathogenesis, clinical epidemiology, and therapies targeting arterial stiffness in ESRD, discussing recent advances and high-priority goals of future research in these important areas.

Noninvasive perioperative monitoring of arterial function in patients with kidney transplantation

Development of atherosclerosis is accelerated in kidney transplant recipients. Impaired metabolic pathways have a complex effect on the arterial wall, which can be measured by noninvasive techniques. Few data are available on the change of stiffness parameters in the postoperative course, so in this study we analyzed the stiffness parameters of kidney transplant recipients during the perioperative period. Seventeen successful primary kidney transplant patients with uneventful postoperative period (7 woman, 10 men; 46.16 ± 12.19 years) were involved in our short-term prospective longitudinal study. We analyzed the correlation between noninvasively assessed stiffness parameters (pulse wave velocity [PWV], augmentation index [AIx], pulse pressure [PP], systolic area index, diastolic area index, diastolic reflection area), ankle-brachial index (ABI), and laboratory parameters (creatinine, glomerular filtration rate, urea, haemoglobin, C-reactive protein). Stiffness parameters were measured with a Tensiomed Arteriograph. These parameters were assessed before the transplantation, and 24 hours, and 1 and 2 weeks after surgery under standard conditions. We found that creatinine (P = .0008) and C-reactive protein (P = .006) serum levels decreased, and glomerular filtration rate increased significantly (P = .0005). We revealed that PWV (P = .0075) and AIx (P = .013) improved significantly. There was no significant change in ABI, PP, and the other monitored parameters. Along with the available data in the literature, our findings suggest that kidney transplantation has a positive effect on the arterial function.