Background: At present, there is a growing body of evidence implicating growth hormone (GH) and/or insulin-like growth factor-I (IGF-I) in the intricate cascade of events connected with the regulation of heart development and hypertrophy. In addition, advanced clinical manifestations of abnormal GH levels almost always include impaired cardiac function which may reduce life expectancy of those patients. Cardiac affection is probably related to a primary impairment of heart structure and function and to metabolic changes such as hyperlipidemia, increased body fat and premature atherosclerosis. Aim: To evaluate the effect of growth hormone therapy on cardiovascular risk factors such as lipid profile, insulin resistance, and left ventricular systolic and diastolic function. Patients and methods: This prospective cohort study was carried out at Pediatric Cardiology and Endocrinology Units of Children’s Hospital and Clinical Pathology Laboratory, Faculty of Medicine, Zagazig University. Forty-one participants were included in the study. They were classified into growth hormone deficiency group: comprised 25 children and idiopathic short stature group comprised 16 children. Lipid profile and insulin resistance were assessed and Echocardiography was performed. Results: There were statistically significant differences between studied groups regarding initial mitral A wave velocity (higher in GH deficiency) and E/A wave velocity ratio (higher in idiopathic short stature) while 6 months after therapy, both groups did not show significant difference. Within group of GH deficiency, there were significant increases in E wave velocity, E/A velocity ratio, E`/A` velocity ratio following rh-GH treatment. We found a significant negative correlation between percent of final height to lowest target height and age, initial Z score of BMI and initial SDS of height. Conclusion: Using traditional Doppler, we found that LV early diastolic filling was better in GH deficient patients than in cases with idiopathic short stature and it was also better in terms of tissue Doppler derived E`/A` velocity ratio in both groups of patients following rh-GH replacement. Among patients with GH deficiency, LV early diastolic function showed significant improvement after rh-GH treatment. After therapy with rh-GH at a median dose of 0.04 mg/kg/day, height, weight and SDS of height showed significant enhancement. The percentage of current height to the lowest target height correlated negatively with both initial Z score of BMI and SDS of initial height. Insulin resistance was higher in patients with GH deficiency compared to those with idiopathic short stature.