Plasma nitric oxide level in myocardial disorders with left ventricular diastolic dysfunction

Nitric oxide is a free radical that is elevated in the plasma of patients with heart failure due to contractile dysfunction. This study examine the relation between plasma NO level and Left Ventricular [LV] diastolic function and its aetiology in heart failure patients in the pediatric age group. We performed echocardiographic Doppler studies in 47 patients [mean age of 6.16 +/- 2.8 years, 31 males and 16 females] with congestive heart failure. Left ventricular diastolic dysfunction was classified as either a restrictive [RFP] or non restrictive filling pattern [non-RFP]. Same day venous total nitrite and nitrate levels were measured by colourimetric assay. Plasma NOx level was significantly higher in the studied patients than the control group [141 +/- 54 and 43 +/- 4 micromol/L, respectively, p<0.001]. ROC curve found that the cut off point for plasma NOx level was 60 micromol/L to differentiate between normal children and patients with heart failure. Patients with RFP showed insignificantly higher levels of plasma NOx than the non-RFP patients. Only in muscular dystrophy patients, there were negative correlation between plasma NOx level and LV ejection fraction [r = -0.61, p = 0.06] and LV fractional shortening [r = -0.64, p = 0.04]. On correlating the plasma NOx levels to the severity of heart failure by multiple linear regression analysis, the pulmonary artery systolic pressure was the only variable independently associated with an elevated plasma NOx level [p = 0.05]. Plasma NOx level is elevated in patients with isolated diastolic heart failure. In addition, in patients with LV systolic failure, the severity of LV diastolic dysfunction determines the amount of NO production

Cardiac structural and functional abnormalities in growth hormone deficient children before and after growth hormone replacement therapy

This study included 45 patients [30 males and 15 females] with GH deficiency with mean age of 11.5 +/- 4.6 years. All patients were subjected to thorough clinical examination with special emphasis on the resting heart rate and blood pressure, auxological evaluation including the height standard deviation [SD], height velocity SD, body mass index [BMI] and body surface area [BSA], laboratory investigations [CBC, s. sodium, potassium and kidney functions] as well as one and two dimensional echocardiography to determine the left ventricular diastolic dimension [EDD], end systolic dimension [ESD], posterior wall and interventricular septal thickness, left ventricular mass and mass index. Thirty patients received recombinant human GH [rhGH] therapy for six months [rhGH group], while the remaining fifteen patients [matching the rhGH group in both age and sex] were considered as an index group for comparative purposes. The same initial evaluations were repeated for both groups six months later. It was concluded that although children with GH deficiency had cardiac structure and function within the normal ranges for their age and sex, GH replacement therapy improved their cardiac performance and ventricular mass with subsequent favorable effect on their life and cost-benefit ratio. However, long term studies are needed to guard against and early detect cardiac hypertrophy that may accompany prolonged GH therapy