Assessment of Ventricular Outflow Tract in Macrosomic Neonates

Abstract

Introduction: Fetal macrosomia is encountered in up to 10% of all deliveries. It occurs in 15-45% of diabetic pregnancies. Factors associated with fetal macrosomia include genetics; duration of gestation; presence of gestational diabetes; high pre-pregnancy body mass index (BMI); excessive gestational weight gain and diabetes mellitus. Macrosomia is reportedly associated with neonatal morbidity, neonatal injury, maternal injury, and cesarean delivery. Moreover, shoulder dystocia, brachial plexus injury, skeletal injuries, meconium aspiration, prenatal asphyxia, hypoglycemia, and fetal death. All types of maternal diabetes are risk factors for macrosomia and can affect the foetal cardiac development in the form of Hypertrophic cardiomyopathy and congenital cardiac malformation. Aim of work: To evaluate the cardiac changes and ventricular outflow tracts in macrosomic neonates clinically and by 2D transthoracic echocardiography. Patients and Methods: This prospective study was carried out in NICU of Sayed Galal University Hospital on fifty macrosomic neonates’ thorough detailed history, clinical examination, Chest X-ray, important laboratory investigation, two dimensional M-mode and Doppler echocardiographic examination. Results: The fifty macrosomic neonates consisted of 29 males (58%) and 21 females (42%) with mean age ± SD of 2.16±0.84 days (range, 1-5 days). Statistically, significant relation between inter ventricular septum diastole (IVSD) (mm) according to HbA1c level, increase IVSD with increase HbA1c level, and show statistically significant relation between inter ventricular septum diastole (mm) and LTVOTO. When IVSD increase the incidence of LVOTO increase While TABSE decrease with the increase in IVSD. It also showed significant negative correlation between IVSD and MPI and PAP. Conclusion: Elevated maternal HbA1c level can lead hypertrophic cardiomyopathy mainly septal hypertrophy, which increased incidence of ventricular outflow tract obstruction. These echocardiographic findings (TAPSE and MPI) seem to be a better index of the cardiac outcome of macrosomic neonates than other clinical, laboratory or radiological parameters. Recommendations: Early echocardiographic examination for early detection of myocardial dysfunction or cardiac defect is essential in all macrosomic neonates andIDM even those without audible murmur, especially so if not improving with proper intervention. Echocardiographic indices especially TAPSE and Tei index for all macrosomic neonates to detect early cardiac changes in particular left ventricular dysfunction.