Children with chronic renal disease undergoing dialysis or conservative treatment--differences in structural and functional echocardiographic parameters

Left Ventricular Mass and Functions in Egyptian Children with Chronic Kidney Disease in Comparison to Normal Subjects

Left ventricular hypertrophy (LVH) and cardiac fibrosis are common accompaniments of chronic kidney disease (CKD). They can be rather easily assessed by conventional cardiac imaging modalities, most practically by M-mode or two-dimensional (2D) echocardiography, with adequate recognition of pitfalls. This study uncovers the impact of impaired renal function on left ventricular mass (LVM) and LVM index (LVMI) in children with CKD on regular hemodialysis (HD) attending the Zagazig University Hospital for Children. A total of 80 Egyptian children, out of which 40 subjects having a mean age of 11.2 ± 3.12 years were cases with CKD in stage 5 on regular HD and the other 40 healthy subjects as controls, with a mean age of 12.2 ± 2.54 years, were included in the study and assessed for LVH and LVMI by 2D echocardiography. HD children had a significantly higher mean LVMI (102.3 ± 19.1 vs. 49.6 ± 4.11 g/m², P <0.001) than controls. Relative wall thickness was significantly higher in the patients with CKD patients on HD compared with controls (P <0.001) with a mean value of 0.46 indicating concentric LVH in renal patients. Comparing mitral inflow velocities between both the groups revealed that the patient group had a significant decrease in mitral E-wave velocity (0.88 ± 0.2 vs. 1.1 ± 0.1 m/sec, P <0.001) and E/A velocity ratio (1.3 ± 0.3 vs. 1.7 ± 0.3, P <0.001) in comparison with the control group, but there was no statistically significant difference in A-wave velocity. This indicates early diastolic dysfunction in CKD patients. LV mass changes in CKD children were strongly related to hypocalcemia and Vitamin D deficiency. Children with CKD are prone to the development of cardiac diastolic dysfunction and LVH, so early and regular echocardiographic studies of all children with CKD are recommended to detect early cardiac changes and institute interventions.

High Fibroblast Growth Factor 23 as a Biomarker for Severe Cardiac Impairment in Children with Chronic Kidney Disease: A Single Tertiary Center Study

INTRODUCTION

Left ventricular hypertrophy (LVH) is the most common cardiac abnormality in chronic kidney disease (CKD). Changes in cardiac geometry and functions may occur in an early stage and worsen as CKD progresses. Recently, the role of fibroblast growth factor 23 (FGF23) is being highlighted and investigated in CKD-related cardiomyopathy. However, only a few studies have reviewed the utilization of FGF23 as a diagnostic biomarker in the pediatric CKD population.

PURPOSE

This study aimed to identify the role of FGF23 as a biomarker in assessing cardiac changes in children with CKD.

PATIENTS AND METHODS

We conducted a cross-sectional study that involved children aged 2 to 18 years old with CKD stages 2 to 5D in Dr. Sardjito General Hospital, Yogyakarta, Indonesia. The level of FGF23 was measured using an immunometric enzyme-linked immunosorbent assay. LVMI, RWT, and left ventricular ejection fraction (LVEF) were assessed with echocardiography. Receiver-operating characteristic (ROC) analyses were conducted to assess the diagnostic performance of FGF23 in detecting LVH with impaired contractility.

RESULTS

A total of 43 children with CKD stages 2 to 5D were included, among whom the prevalence of LVH diagnosis was 95.35%. The area under the curve (AUC) of FGF23 to assess LVH and systolic dysfunction was 0.82 (95% CI 0.62-1.0), and the optimal cutoff point was 1413 RU/mL (sensitivity 80%, specificity 78.95%). The median concentration of FGF23 increased with the decreasing eGFR and the increasing LVMI although the systolic and diastolic functions were preserved.

CONCLUSION

FGF23 might be used as an early biomarker to detect cardiac changes in pediatric CKD patients, particularly for LVH and impaired systolic function among children with CKD stage 2 and higher.

Cardiovascular risk factors in children on dialysis: an update

Cardiovascular disease (CVD) is a life-limiting comorbidity in patients with chronic kidney disease (CKD). In childhood, imaging studies have demonstrated early phenotypic characteristics including increases in left ventricular mass, carotid artery intima-media thickness, and pulse wave velocity, which occur even in young children with early stages of CKD. Vascular calcifications are the signature of an advanced phenotype and are mainly found in adolescents and young adults treated with dialysis. Association studies have provided valuable information regarding the significance of a multitude of risk factors in promoting CVD in children with CKD by using intermediate endpoints of measurements of surrogate parameters of CVD. Dialysis aggravates pre-existing risk factors and accelerates the progression of CVD with additional dialysis-related risk factors. Coronary artery calcifications in children and young adults with CKD accumulate in a time-dependent manner on dialysis. Identification of risk factors has led to improved understanding of principal mechanisms of CKD-induced damage to the cardiovascular system. Treatment strategies include assessment and monitoring of individual risk factor load, optimization of treatment of modifiable risk factors, and intensified hemodialysis if early transplantation is not possible.

Comparison of echocardiographic changes in children with primary hypertension and hypertension due to mild to moderate chronic kidney disease

BACKGROUND

Chronic systemic hypertension has a well-known association with increased cardiovascular morbidity and mortality. One of the most important target organs affected in systemic hypertension is the heart. In addition, chronic kidney disease (CKD) further increases the mortality from cardiovascular disease. The aim of this study was to evaluate the differences in the cardiovascular changes in pediatric patients with primary hypertension (pHTN) vs. those with secondary hypertension from chronic kidney disease (CKD-HTN).

METHODS

This was a retrospective chart review of patients with CKD-HTN and pHTN. The medical records were reviewed for anthropometric data, biochemical assessment of renal function, and for cardiovascular changes on echocardiogram.

RESULTS

Twenty-three patients with pHTN and 29 patients with CKD-HTN were included in the study. There were no differences in age, gender, weight, height, body mass index, and blood pressure between the 2 groups. There was a high prevalence of left ventricular diastolic dysfunction among both the groups (CKD-HTN 25 vs. pHTN 26%). Reduced mitral valve inflow Doppler E/A ratio, a marker of left ventricular diastolic dysfunction in echocardiogram, was more pronounced in CKD-HTN patents, in comparison to those with pHTN (p = 0.042). Also, diastolic function worsened with declining glomerular filtration rate in patients with CKD-HTN. Similarly, patients with CKD-HTN had a larger aortic root dimension when compared to patients with pHTN (p = 0.049).

CONCLUSIONS

The prevalence of left ventricular diastolic dysfunction is similar in patients with pHTN and CKD-HTN. Patients with CKD-HTN appear to have more severe diastolic dysfunction and larger aortic root dimensions.

Cardiovascular risk in children and adolescents with end stage renal disease

OBJECTIVES

To evaluate cardiovascular involvement in children and adolescents with End Stage Renal Disease (ESRD) and to characterize the main risk factors associated with this outcome.

METHODS

Cross-sectional study of 69 children and adolescents at renal transplantation and 33 healthy individuals matched by age and gender. The study outcomes were left ventricular mass z-score (LVMZ) and carotid artery intima-media thickness (CIMT). The potential risk factors considered were age, gender, CKD etiology, use of oral vitamin D and calcium-based phosphate binders, systolic and diastolic blood pressure, body mass index z-score, time since diagnosis, dialysis duration, serum levels of ionic calcium, phosphorus, parathyroid hormone, fibroblast growth factor (FGF 23), uric acid, homocysteine, cholesterol, triglycerides, C-reactive protein (CRP), vitamin D and hemoglobin.

RESULTS

In the multivariate analysis, the factors associated with LVMZ were dialysis duration, age, systolic blood pressure, serum hemoglobin and HDL cholesterol levels. Regarding CIMT, in the multivariate analysis, systolic blood pressure was the only factor associated with the outcome.

CONCLUSION

Children exhibited important cardiovascular involvement at the time of the renal transplantation. Both of the studied outcomes were independently associated with systolic blood pressure. For this reason, controlling blood pressure seems to be the main therapy to minimize cardiovascular involvement in children with ESRD.

Cardiac and Vascular Target Organ Damage in Pediatric Hypertension

Atherosclerosis begins in youth and is associated with the presence of numerous modifiable cardiovascular (CV) risk factors, including hypertension. Pediatric hypertension has increased in prevalence since the 1980s but has plateaued in recent years. Elevated blood pressure levels are associated with impairments to cardiac and vascular structure and both systolic and diastolic function. Blood pressure-related increases in left ventricular mass (LVM) and abnormalities in cardiac function are associated with hard CV events in adulthood. In addition to cardiac changes, key vascular changes occur in hypertensive youth and adults. These include thickening of the arteries, increased arterial stiffness, and decreased endothelial function. This review summarizes the epidemiologic burden of pediatric hypertension, its associations with target organ damage (TOD) of the cardiac and vascular systems, and the impact of these adverse CV changes on morbidity and mortality in adulthood.

Myocardial dysfunction occurs prior to changes in ventricular geometry in mice with chronic kidney disease (CKD)

Uremic cardiomyopathy is responsible for high morbidity and mortality rates among patients with chronic kidney disease (CKD), but the underlying mechanisms contributing to this complex phenotype are incompletely understood. Myocardial deformation analyses (ventricular strain) of patients with mild CKD have recently been reported to predict adverse clinical outcome. We aimed to determine if early myocardial dysfunction in a mouse model of CKD could be detected using ventricular strain analyses. CKD was induced in 5-week-old male 129X1/SvJ mice through partial nephrectomy (5/6Nx) with age-matched mice undergoing bilateral sham surgeries serving as controls. Serial transthoracic echocardiography was performed over 16 weeks following induction of CKD. Invasive hemodynamic measurements were performed at 8 weeks. Gene expression and histology was performed on hearts at 8 and 16 weeks. CKD mice developed decreased longitudinal strain (-25 ± 4.2% vs. -29 ± 2.3%; P = 0.01) and diastolic dysfunction (E/A ratio 1.2 ± 0.15 vs. 1.9 ± 0.18; P < 0.001) compared to controls as early as 2 weeks following 5/6Nx. In contrast, ventricular hypertrophy was not apparent until 4 weeks. Hearts from CKD mice developed progressive fibrosis at 8 and 16 weeks with gene signatures suggestive of evolving heart failure with elevated expression of natriuretic peptides. Uremic cardiomyopathy in this model is characterized by early myocardial dysfunction which preceded observable changes in ventricular geometry. The model ultimately resulted in myocardial fibrosis and increased expression of natriuretic peptides suggestive of progressive heart failure.