Late Effects of Renal Transplantation on Endothelial Functions and Cardiac Morphology

Left Ventricular Hypertrophy After Renal Transplantation: Systematic Review and Meta-analysis

Background

Left ventricular hypertrophy (LVH) in patients with end stage renal disease undergoing renal replacement is linked to an increased risk for cardiovascular diseases. Dialysis does not completely prevent or correct this abnormality, and the evidence for kidney transplantation (KT) varies. This analysis aims to explore the relationship between KT and LVH.

Methods

MEDLINE and Scopus were systematically searched in October 2023. All cross-sectional and longitudinal studies that fulfilled our inclusion criteria were included. Outcome was left ventricular mass index (LVMI) changes. We conducted a meta-analysis using a random effects model. Meta-regression was applied to examine the LVMI changes dependent on various covariates. Sensitivity analysis was used to handle outlying or influential studies and address publication bias.

Results

From 7416 records, 46 studies met the inclusion criteria with 4122 included participants in total. Longitudinal studies demonstrated an improvement of LVMI after KT -0.44 g/m2 (-0.60 to -0.28). Blood pressure was identified as a predictor of LVMI change. A younger age at the time of KT and well-controlled anemia were also associated with regression of LVH. In studies longitudinally comparing patients on dialysis and renal transplant recipients, no difference was detected -0.09 g/m2 (-0.33 to 0.16). Meta-regression using changes of systolic blood pressure as a covariate showed an association between higher blood pressure and an increase in LVMI, regardless of the modality of renal replacement treatment.

Conclusions

In conclusion, our results indicated a potential cardiovascular benefit, defined as the regression of LVH, after KT. This benefit was primarily attributed to improved blood pressure control rather than the transplantation itself.

Arterial vessel reactivity in patients in the long term after kidney transplantation - preliminary study

INTRODUCTION

The aim of this study was to evaluate the endothelial-dependent and -independent arterial vessels' reactivity in patients in the long term after kidney transplantation (KTx).

MATERIAL AND METHODS

The study included 36 (15 females; 21 males) patients after KTx with good, stable graft function and 94 healthy individuals (51 males, 43 females). The endothelial-dependent dilatory capacity of the brachial artery was estimated by an ischemic test (flow-mediated dilation - FMD), and independent by nitroglycerin-mediated vasodilation (NMD). The results were shown for age-related groups and compared with age-related healthy people.

RESULTS

KTx patients were mean 5.1 ±2.3 years after transplantation with the mean estimated glomerular filtration rate (eGFR) 50.3 ±17.1 ml/min/1.73 m². The mean vessel diameter before tests was significantly larger in healthy people than in KTx patients. The FMD test showed vasodilation becoming weaker along with age in both groups, but in KTx patients this relationship was clearly enhanced. The NMD was delayed in relation to age, and in KTx patients was preserved, being only slightly weaker than in healthy people.

CONCLUSIONS

Both endothelium-dependent and -independent arterial wall reactions decrease with age. The endothelial-dependent vascular response is more attenuated in KTx patients than the independent one. The endothelium-independent vasodilation in KTx patients is comparable with that in healthy people.

Changes in oxidative stress in renal graft patients receiving calcineurin inhibitors: cyclosporine versus tacrolimus

OBJECTIVES

The effects of calcineurin inhibitors on oxidative stress after renal transplant are obscure. This study sought to investigate the changes in plasma oxidative stress and lipid levels in patients receiving cyclosporine or tacrolimus before and after renal transplant for 6 months.

MATERIALS AND METHODS

Twenty-one patients and 15 healthy controls were involved in our study. Twelve of the patients were treated with cyclosporine and 9 were treated with tacrolimus. Plasma malondialdehyde, nitrite/nitrate, vitamin C, vitamin E, and plasma glutathione levels, as well as total cholesterol and triglyceride levels, were evaluated before and after transplant for 6 months.

RESULTS

Before the transplant, patients had higher malondialdehyde and plasma glutathione levels than did healthy controls (3.76 ± 0.79 nmol/mL vs 3.21 ± 0.57 nmol/mL; P < .05, and 66.6 ± 23.2 μmol/L vs 43.3 ± 26.9 μmol/L; P < .05). In the overall group of patients, a significant increase in malondialdehyde levels was detected 3 and 6 months after transplant (3.76 ± 0.79 nmol/mL vs 4.38 ± 0.87 nmol/mL in the third month; P = .02; and 3.76 ± 0.79 nmol/mL vs 4.28 ± 0.69 nmol/mL in the sixth month; P = .04). A significant reduction in plasma glutathione levels 1 month after transplant and nitrite/nitrate levels 6 months after transplant was found. No changes in vitamin C and vitamin E levels were detected before and after transplant. After 3 and 6 months of transplant, cyclosporine-treated patients had higher levels of total cholesterol and triglycerides when compared with tacrolimus-treated patients.

CONCLUSIONS

An enhancement in plasma malondialdehyde levels was found after transplant at 6-month follow-up. However, no significant change in vitamin C, vitamin E, nitrite/nitrate levels between patients and controls was recorded. Although both calcineurin inhibitors showed similar effects on oxidative stress, cyclosporine-treated patients had higher levels of total cholesterol and triglycerides.