Persistent pulmonary hypertension of the newborn presenting as the primary manifestation of intracranial arteriovenous malformation of the Vein of Galen.

Arteriovenous malformations of the Vein of Galen continue to present diagnostic and therapeutic challenges in the neonatal period. Approximately 40-50% of all malformations of the Vein of Galen present in the neonatal period, usually with congestive heart failure. These neonates represent the most severe cases and are also the most difficult to manage. We report a case of a neonate with a Vein of Galen Malformation who presented with cyanosis, a cardiac murmur, and severe persistent pulmonary hypertension of the newborn. Cardiac failure developed later in the patient's course. The degree of pulmonary hypertension on echocardiography was used to time endovascular embolization of the Vein of Galen Malformation. Following embolization, his pulmonary hypertension subsided dramatically. We speculate that pulmonary hypertension associated with Vein of Galen Malformations has been underestimated in the morbidity and demise of these neonates, and should be more aggressively monitored and treated.

Flexible bronchoscopy in the management of congenital lobar emphysema in the neonate.

This paper describes the case of a 3 kg neonate who had congenital lobar emphysema of the left upper lobe (LUL). He was in severe respiratory distress with a fraction of inspired oxygen of 0.8. Chest x-ray showed hyperlucent expanded left hemithorax and marked mediastinal shift. Following flexible bronchoscopy and introduction of ultrathin bronchoscope into the LUL bronchus, symptoms and chest x-ray improved markedly. Flexible bronchoscopy resulted in emergency relief of his initial respiratory distress, and left upper lobe lobectomy was performed electively three days later.

Serial assessment of ductus arteriosus hemodynamics in hyaline membrane disease.

OBJECTIVES: To assess the efficacy of Doppler echocardiography (DE) in the quantification of patent ductus arteriosus (PDA) shunt volume and to correlate PDA shunt volume with clinical outcome in infants with hyaline membrane disease. METHODS: Ninety-eight DE studies were performed in 30 preterm ventilated infants with hyaline membrane disease within the first 24 hours of age and then at 48-hour intervals to a maximum of three studies while ventilated with a final study after extubation. Right and left ventricular outputs (QRV and QLV, respectively) and PDA flow were calculated using cross-sectional area and flow velocity integrals. Left atrial-to-aortic root diameter measurements were also taken. Clinical outcomes were correlated with the shunt fraction (QLV/QRV). RESULTS: QLV/QRV demonstrated a linear relationship with the left atrial-to-aortic root diameter ratio (n = 92; r = .79). In the absence of a PDA (n = 33 studies), QRV versus QLV demonstrated a linear relationship (r = .88). In the presence of a PDA (n = 64 studies) the mean QLV (334 +/- 133 ml/kg per minute) was significantly greater than the mean QRV (237 +/- 84 ml/kg per minute). There was a linear relationship between QLV-QRV (PDA shunt volume) and PDA flow (n = 60; r = .84). In studies with exclusive left-to-right shunting at the PDA (n = 48), the mean QLV-QRV (112 +/- 83 ml/kg per minute) was significantly higher than in those with bidirectional shunting (n = 16; mean QLV-QRV = 50 +/- 27 ml/kg per minute). Two infants with severe intraventricular hemorrhage (IVH grade 3) and two infants with periventricular leukomalacia (PVL) had significantly higher QLV/QRV (2.09 +/- 0.36 and 1.67 +/- 0.02 respectively) than those with no IVH (n = 6; QLV/QRV = 1.31 +/- 0.18) or those with IVH grades 1 and 2 (n = 8; QLV/QRV = 1.48 +/- 0.27). There was no difference in QLV/QRV in infants with or without bronchopulmonary dysplasia and retinopathy of prematurity. Necrotizing enterocolitis did not develop in any of the 30 infants. CONCLUSION: PDA shunt volume can be quantified by DE. Larger studies are needed to correlate clinical outcome with QLV/QRV.

Pulmonary vascular resistance during lipid infusion in neonates.

Using two-dimensional echocardiography, pulmonary vascular resistance was estimated from right ventricular pre-ejection period to ejection time (RVPEP/ET) in 11 preterm infants with respiratory distress, to test the effect of different doses of continuous lipid infusion. Echocardiography was performed at baseline with no lipid infusing 2 and 24 hours after 1.5 and 3 g/kg/day of intravenous lipid, 24 hours after discontinuing intravenous lipid emulsion, and 2 hours after restarting intravenous lipid. After 24 hours of intravenous lipid at 1.5 g/kg/day the RVPEP/ET rose to mean (SD) 0.287 (0.03) from a baseline value of 0.225 (0.02) and to 0.326 (0.05) after 24 hours of intravenous lipid at 3 g/kg/day. Pulmonary arterial pressure returned to baseline 24 hours after the intravenous lipid had been discontinued. Continuous 24 hour infusion of lipid caused significant dose and time-dependent increases in pulmonary vascular resistance. Intravenous lipid may aggravate pulmonary hypertension.

The echocardiographic assessment of the human fetal foramen ovale.

The foramen ovale size and interatrial flow patterns were studied by combined real-time and Doppler echocardiography in 100 normal human fetuses between 20 and 38 weeks gestation. The foramen ovale, atrioventricular, and semilunar valve diameters increased linearly with gestational age. The foramen flap motion and interatrial flow patterns showed biphasic flow patterns with interatrial flow reversal with atrial systole. Color flow mapping of the diameter of the interatrial flow profile showed good correlation with the foramen ovale size as measured by two-dimensional echocardiography. These data represent the first large study of the normal human foramen ovale correlated with gestational age, thus expanding the reference base for ultrasound assessment of fetal heart.

Prenatal detection of foramen ovale obstruction without hydrops fetalis.

A case of prenatal echocardiographic diagnosis of obstruction of the foramen ovale is described. Presentation was the ultrasound detection of unexplained marked right atrial and right ventricular dilation without fetal hydrops. It is speculated that fetal outcome depends on the severity and time of onset of foramen ovale obstruction in utero.