Premature closure of the foramen ovale and hypoplasia of the left heart.

Although premature closure of the foramen ovale has been proposed as a possible cause of hypoplastic left heart syndrome, very few such cases have been described. We have seen two examples of the combination and no associated malformations. In both the foramen was firmly closed on its left atrial aspect and the dimensions of the left sided structures were well below normal values.

Endocardial fibroelastosis with coronary artery thromboembolus and myocardial infarction.

We report a case of an 18-month-old male, born to a woman with third trimester febrile illness, who had a history of congestive heart failure and respiratory distress, cardiomegaly, and electrocardiographic (ECG) findings suggestive of cardiomyopathy and myocarditis. After gradual improvement in heart size and function with pharmacologic therapy, he developed a terminal episode of respiratory distress and cardiogenic shock, with ECG findings of an anterolateral infarct. At autopsy it was found that endocardial fibroelastosis with mural thrombi in the left ventricle had been complicated by thromboembolism to the left anterior descending coronary artery, resulting in transmural infarction of the anteroseptal region of the left ventricle. Myocardial infarction is a potential but unusual thromboembolic complication of endocardial fibroelastosis. A high index of suspicion for coronary artery thromboemboli should be maintained in pediatric patients with cardiomyopathy and suspected myocardial infarction.

Cerebral arteriovenous malformation presenting as persistent fetal circulation. Diagnosis by cross-sectional echo.

Two infants with cerebral arteriovenous malformation (CAVM), both initially seen with persistent fetal circulation, were studied with cross-sectional echo. The descending aorta, which is dilated in infants with CAVM, was identified in the subxiphoid four-chamber and short-axis views in both infants. In both infants the arteriovenous malformation was readily identified by cross-sectional echo as a lucency within the brain. Pulsation of the cranial lucency was noted in one infant, but only still frames from the head echo were preserved in the other infant, and pulsation was not commented on in that case.

Selective cyanosis of the right arm. Isolation of right subclavian artery from aorta with bilateral ductus arteriosus and pulmonary hypertension.

A sixteen-month-old child presented with cyanosis of the right arm. Investigation revealed bilateral persistent ductus arteriosus with isolation of the right subclavian artery from the aorta. Pulmonary vascular resistance and pulmonary arterial pressure were elevated so that the right subclavian artery received desaturated blood from the right pulmonary artery via the persistent right ductus arteriosus.

Gentamicin pharmacokinetics in neonates with patent ductus arteriosus.

OBJECTIVES: To determine the effect of patent ductus arteriosus on the pharmacokinetics of gentamicin in neonates and to examine whether any particular pharmacokinetic parameter is of value as a marker of patent ductus arteriosus. DESIGN: Cohort study of neonates treated with gentamicin, according to a standard dosing protocol. SETTING: A 24-bed, Level III, neonatal intensive care unit. PATIENTS: Neonates treated with gentamicin at the time of admission to the neonatal intensive care unit, using a standard protocol, and who were < 36 wks of gestational age. INTERVENTIONS: All patients received a gentamicin loading dose, and had gentamicin concentrations measured at 2 and 12 hrs after this dose, in order to determine pharmacokinetic parameters and calculate the optimum maintenance dose. Those neonates subsequently diagnosed to have patent ductus arteriosus, based on clinical suspicion and echocardiographic confirmation, were compared with those neonates without clinically suspected patent ductus arteriosus. Gentamicin pharmacokinetic parameters were calculated using a one-compartment model. MEASUREMENTS AND MAIN RESULTS: A total of 322 courses of gentamicin were administered (patent ductus arteriosus, n = 106; control, n = 216). Gentamicin clearance was decreased in the patent ductus arteriosus group vs. the control group (40.02 vs. 44.73 mL/kg/hr; p < .0108). Volume of distribution was greater for patent ductus arteriosus patients (0.61 L/kg) than for controls (0.54 L/kg) (p < .0002). Also, volume of distribution was a useful marker for presence of patent ductus arteriosus, with a 92% specificity for patent ductus arteriosus. CONCLUSIONS: Gentamicin dosing should be altered in neonates with patent ductus arteriosus to reflect the impact of higher volume of distribution and lower clearance. When the gentamicin volume of distribution exceeds 0.7 L/kg, it may be of predictive value for the presence of patent ductus arteriosus.