Evaluation of the Cardiovascular System in Children and Adolescents with Nephrotic Syndrome

Background: Patients with nephrotic syndrome (NS) are assumed to be at increased risk for atherosclerosis and coronary heart disease (CHD), probably because of NS associated hyperlipidemia.
Objectives: This study was aimed at evaluation of the cardiovascular system in children and adolescents with nephrotic syndrome.
Methods: Forty-two children and adolescents attending the pediatric Nephrology Unit of Ain Shams University Children′s Hospital were enrolled in this study. They were 24 males and 18 females. Their ages ranged between 3 and 18 years with a mean of 10.47 ± 4.62 years. They were subdivided into 2 subgroups; one included 21 patients (50%) having proteinuria and other included 21 patients (50%) in remission. Ten healthy age and sex matched children served as a control group. All patients were subjected to thorough history taking and clinical examination. All subjects in the study underwent laboratory investigations including hemoglobin level, serum creatinine, albumin, triglycerides (TGs), cholesterol, low and high density lipoprotein (LDL and HDL), electrocardiogram (ECG) as well as echocardiography.
Results: Serum TGs, LDL and cholesterol were significantly higher in nephrotic patients than controls (p<0.01), whereas HDL levels were comparable. Serum albumin was inversely correlated to serum TGs, LDL and cholesterol (p < 0.05 for each). ECG did not reveal any ischemic changes in nephrotic patients. Echocardiography showed normal systolic function in all patients.  Diastolic dysfunction including abnormal relaxation or restrictive filling was detected in 30 patients (71%). Diastolic dysfunction was evidenced by abnormal isovolumic relaxation time (IVRT), deceleration time of the peak early filling velocity (DT) and/or decreased E/A ratio which is the ratio between peak early filling (peak E) velocity and peak late (peak A) velocity. Left ventricular mass (LVM) was increased and was positively correlated to disease duration and number of relapses (p < 0.05).
Conclusions: Nephrotic patients did not have ischemic changes in the resting ECG, whereas their echocardiography revealed diastolic dysfunction and increased left ventricular mass. The duration of hypertension and hyperlipidemia make nephrotic patients more susceptible to myocardial ischemia, so they must be properly controlled. More sensitive diagnostic techniques and follow up of the nephrotic children for possible development of CHD in young adulthood is                 recommended.