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

Abstract

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.

Graphical abstract

FIGURE 1.

Flow diagram of study selection process.

FIGURE 2.

Forest plot depicting the changes in LVMI in patients before and after KT. Estimated effect sizes for LVMI changes before and after KT are presented as standardized mean difference and 95% CI. Heterogeneity analysis using I² and Tau2 is illustrated. CI, confidence interval; KT, kidney transplantation; LVMI, left ventricular mass index; TE, total effect.

FIGURE 3.

Meta-regression analysis using changes in SBP as covariate. Meta-regression analysis suggests that the reduction of SBP is a significant predictor for the decline of LVMI. The x-axis represents change in systolic pressure (mm Hg), and the y-axis represents change in LVMI as standardized mean difference. △SBP, standardized mean difference in systolic blood pressure (mm Hg) between baseline and the second measurement; LVMI, left ventricular mass index.

FIGURE 4.

Forest plot depicting the changes in LVMI in renal recipients compared with patients remaining on dialysis. Estimated effect sizes for LVMI changes are presented as standardized mean difference and 95% CI. Heterogeneity analysis using I² and Tau2 is illustrated. CI, confidence interval; KT, kidney transplantation; LVMI, left ventricular mass index.

FIGURE 5.

Meta-regression analysis for kidney transplantation vs dialysis separated using changes in SBP as a covariate. To evaluate the impact of blood pressure control on LVMI, we separated the KT and control (dialysis) groups of longitudinal studies with kidney recipients and patients remaining on dialysis. The reduction in SBP could serve as a predictor for the regression of left ventricular hypertrophy in both KT group and dialysis groups. The x-axis represents change in systolic pressure (mm Hg), and the y-axis represents change in LVMI as standardized mean difference. △SBP, standardized mean difference in systolic blood pressure (mm Hg) between baseline and the second measurement; D, dialysis; KT, kidney transplantation; LVMI, left ventricular mass index.