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Cardiac troponin T (TnT) is a regulatory contractile protein whose detection in the circulation has been shown to be a specific and sensitive marker for ischemic myocardial cell injury both in adult and pediatric populations. We measured serum cardiac TnT in 15 consecutive full-term neonates presenting with bradycardia and electrocardiographic features of transient myocardial ischemia. Their median TnT concentrations (0.5 µg/l, range 0.01–0.37) were statistically comparable to our laboratory reference values for healthy term newborns (median 0.17 µg/l, range 0.01–0.42) (p = NS), but significantly higher with respect to our reference limits for healthy adults (median 0.01 µg/l, range 0.01–0.1) (p < 0.05). Our data demonstrate high TnT levels in neonates during the first days of life with respect to adults and similar TnT concentrations in term infants with and without TMI.

Edwards, 1971;Gomes and McGoon, 1971;Mair et al., 1974;Bharati et al., 1974).In addition, the morphological study of a lesion such as truncus arteriosus communis, in which partial or complete absence of division of the conotruncus is present, may help to clarify which developmental structures take part in the septation of the outflow tracts of the normal heart. With this in mind, we have also examined cases presentina with aortopulmonary septal defect or conal ventricular septal defect which are developmentally related to truncus arteriosus. Definition of termsThe term conus, embryogenetically, refers to the middle third of the bulbus cordis; it is formed by free walls (parietal conus) and by septum (conal septum) derived from the fusion of the conus ridges. Anatomically, the conus corresponds to the outflow tracts of both ventricles and conventionally it refers to the muscular cardiac segments interposed between the semilunar and atrioventricular valves; the conal septum is that portion of the ventricular septum which separates the ventricular infundibula. In the early stages of cardiac development, the atrioventricular channel is separated from the semilunar valves by the parietal conus; a process of differential absorption leads to direct fibrous continuity between mitral and aortic valves, while

Arteriovenous fistula is a relatively rare cause of severe congestive heart failure in the newborn. An intracranial arteriovenous malformation associated with an aneurysm of the great vein of Galen is the most frequent of such malformations and, although well known, it remains a difficult diagnosis in the neonate because the clinical picture first presents with findings suggesting cardiac disease. The newborn with a vein of Galen aneurysm has volume and pressure overload on his myocardium; cyanosis is often present due to persistent fetal circulation; peripheral pulses are generally decreased in amplitude except in those arteries near the fistula where they are bounding, as an expression of a hyperdynamic status. A continuous murmur may be heard over the scalp, but this highly suggestive sign is often not present. The majority of newborns with intracranial arteriovenous fistula die very soon. Unfortunately, most of these infants are at first considered to have congenital heart disease and are, therefore, subjected to cardiac catheterization and angiography, with their well-known risks, before a correct diagnosis is made. Cross-sectional echocardiography, by demonstrating normal intracardiac anatomy, eliminates the need for an invasive investigation in a very sick neonate. Ultrasonography of the head will then provide a rapid and accurate demonstration of the aneurysm of vein of Galen. Cerebral angiography will complete the diagnosis in those cases in which a neurosurgical intervention is contemplated.

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