ABSTRACT
This study was carried out on 100 patients having congenital heart disease [CHO], 63 males and 37 females, their age ranged from 4 months to 12.5 years. In addition, 20 apparently healthy children were taken as a control group. This study was done at AI-Azhar University Hospital on patients attending the cardiology and pediatric cardiology outpatient clinic as well as children admitted to the inpatient department. The CHO patients were divided into groups according to: pulmonary artery systolic pressure [PASP] [normal PASP, mild, moderate or severe pulmonary hypertension], presence or absence of heart failure [HF]: [patients with or without heart failure], correction of the cardiac defect: [patients with or without surgical correction] and cyanosis [cyanotic or non-cyanotic CHO]. All patients were subjected to the following: full history taking, complete physical examination [general and cardiac], plain x-ray chest and heart, electrocardiography, echo cardiography and measurement of serum nitrate levels. Our results showed statistically significant differences in serum nitrate levels particulary between patients with severe pulmonary hypertension and those without and between patients with heart failure and those without. The levels were higher in the HF group compared to non-HF group and the control group. No statistically significant differences in serum nitrate levels were found between patients who previously underwent operations for correction of the cardiac defects and those who did not nor between cyanotic and non-cyanotic groups