SP886A LONGITUDINAL STUDY OF CARDIOVASCULAR FUNCTION IN PEDIATRIC CHRONIC KIDNEY DISEASE AND POST-TRANSPLANT PATIENTS AS ASSESSED BY TISSUE AND PULSE WAVE DOPPLER ECHOCARDIOGRAPHY

Abstract

Introduction and Aims: It is well known that cardiovascular disease (CVD) is one of the most common causes of morbidity and mortality in adult and pediatric chronic kidney disease (CKD). While it is known that left ventricular diastolic dysfunction (LVDD) is an early marker of CVD, there are few longitudinal studies analyzing cardiac function in children. We conducted a prospective 4-years follow up study of cardiovascular function in a cohort of non-dialyzed pediatric chronic kidney disease (CKD) and renal transplanted patients. Specifically, the aims were to evaluate (1) the presence of LVDD in these patients and (2) assess changes in LVDD over time and correlations with possible risk factors. Methods: Thirty-one CKD and 43 transplanted patients as well as 11 children with a normal renal function serving as controls were included and followed prospectively. All patients underwent annual clinical examination, iohexol clearance assessment and diastolic dysfunction analyses using ultrasound Tissue Doppler Imaging (TDI) and pulse wave Doppler (PWD). These functional parameters measures myocardial tissue (É and Á) and blood flow velocities (E and A) representing early and late diastole. Results: The age was similar in the groups (controls 10.2 [4.4 - 17.7], CKD 9.8 [0.8 - 18.8] and transplanted 13.6 [3.3 - 17.7] years, while GFR was 101.5 (11.4), 38.4 (22.8) and 54.5 (20.2) ml/min/1.73m2 respectively. Hypertension was present in 23 % of CKD patients and in 21% of transplanted patients. GFR and blood pressure levels remained unchanged throughout the study. The overall diastolic function analyses using TDI Á and TDI É/Á were worse in CKD [4.0 (1.1) and 3.2 (1.2)] and transplanted patients [4.4 (1.2) and 2.9 (0.88)] compared to controls [3.2 (0.8) and 4.3 (1.2)], p=0.00 and p=0.00 respectively. PWD A and PWD E/A also differed between study groups, p=0.03 and p=0.03. TDI Á, TDI É/Á, PWD A and PWD E/A all correlated statistically significant with an elevated ambulatory systolic and diastolic blood pressure and PWD A with elevated calcium-phosphorus level (all p-values <0,05). There was no significant change over time in any of the diastolic function parameters. All numbers in parenthesis denoting SD-values. Conclusions: Children with CKD have a higher prevalence of LVDD compared to controls. While this was true for both patient groups throughout the study, no progression was seen over the study time period. An increased blood pressure and high calcium and phosphorus levels were found to be associated with LVDD which suggests opportunities for future clinical intervention.