RESUMO
The study included 30 newborn infants born to diabetic mothers in the Obstetrics Department and admitted to the Neonatal Care Unit in Tanta University Hospital. Their gestational age ranged from 31-40 weeks [mean 37.7 +/- 2.13] and birth weight 2.5-5.7 kg [mean 3.61 +/- 0.7 kg]. Ten healthy newborn infants of matched gestational age and sex, born to non-diabetic mothers were included as controls. The aims of the present study were: 1] to define cardiac morphology particularly septal hypertrophy with conventional echocardiography, 2] to use Doppler Tissue Imaging [TDI] echocardiography to detect early cardiomyopathic changes in infants of diabetic mothers, 3] to correlate these data to the parameters of glycemic control of maternal diabetes and 4] to follow up cases with affected myocardium so that their prognosis is determined. Full history and thorough clinical evaluation were done. Laboratory investigations included: cord blood glucose, cord blood insulin, cord blood C-peptide and fetal glycosylated hemoglobin [Hb F1c] as well as maternal glycosylated hemoglobin [Hb A1c]. Cardiac evaluation was done using conventional M-mode, 2-D, and Doppler transmitral flow velocities as well as by TDI to assess cardiac diastolic function. Septal myocardial hypertrophy was detected in 46.66% of the studied cases. Diastolic dysfunction was found in 33.3% by conventional transmitral Doppler flow studies and in 66.6% by TDI. None of the detected myocardial abnormalities were significantly correlated to parameters of maternal diabetes control such as maternal Hb A1c, cord blood insulin, cord blood C-peptide or cord blood Hb F1c. In cases of myocardial hypertrophy or diastolic dysfunction echo-Doppler and DTI studies were repeated till disappearance of myocardial abnormalities. Macrosomia was detected in 20% of the studied cases and did not correlate significantly to maternal diabetes control parameters nor to the myocardial abnormalities. There was no sign of outflow tract obstruction or myocardial systolic dysfunction in any of our studied cases, and myocardial hypertrophy or diastolic dysfunction resolved within 6 months of follow up. We conclude that macrosomia and non-obstructive cardiomyopathy are transient phenomena that still occur in IDM irrespective to the metabolic control of maternal glycemia and it is possible that other factors contribute to such manifestations. The new technique TDI could detect more cases of myocardial diastolic dysfunction in IDM than conventional echo Doppler method and it could be used for early detection and follow up of myocardial abnormalities in IDM