Cardiac troponin T in newborn infants with transient myocardial ischemia.

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 microg/l, range 0.01-0.37) were statistically comparable to our laboratory reference values for healthy term newborns (median 0.17 microg/l, range 0.01-0.42) (p = NS), but significantly higher with respect to our reference limits for healthy adults (median 0.01 micog/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.

The natural history of cardiac rhabdomyoma with and without tuberous sclerosis.

The aim of the present study is to contribute to the knowledge of the natural history of cardiac rhabdomyoma in children with and without tuberous sclerosis. In a retrospective study, 33 children with cardiac rhabdomyoma were collected from three pediatric cardiology centres. In 30/33 patients tuberous sclerosis was associated. High prevalence of cardiac rhabdomyoma was found in infancy, with 21/23 detected before the age of 1 year, and 11/33 before 1 month of age. Cardiac manifestations were present in 19 patients: cardiac rhythm disturbances were detected in 13; in 6/33 a Wolff-Parkinson-White syndrome was documented, of which 4 presented paroxysmal arrhythmias. Obstructive or regurgitative phenomena were present in 5; and in 2 patients surgical removal proved necessary. With the exception of one tumoural mass in the right atrium, all 77 tumours were located somewhere in the ventricles, including at atrio-ventricular valve level. Because of spontaneous regression of most of the tumoural masses, treatment should at first be symptomatic, while surgical removal is required only in life-threatening conditions, as documented in 2 of our 33 patients.

Magnetic resonance angiography in moyamoya disease.

Spontaneous occlusion of the circle of Willis, i.e., moyamoya disease (MMD), is a clinical disease entity angiographically characterized by progressive and bilateral stenosis of the carotid bifurcation, with a hazy collateral network at the base or convexity of the brain. Although the importance of computed tomography (CT) and conventional magnetic resonance (MR) imaging in diagnosing MMD has already been determined, conventional arteriography is still regarded as necessary for definitive diagnosis. Magnetic resonance angiography (MR-A) is a very recent vascular imaging technique which allows noninvasive and direct imaging of vessels without the use of contrast medium. We present four pediatric cases of MMD, evaluated by conventional angiography, CT, MR imaging, and MR-A. Our data demonstrate that MR-A is successful both in allowing detection of occlusive disease of the basal portion of the internal carotid artery and large branch basal cerebral vessels and demonstrating the collateral vessels at the base of the brain. As a noninvasive procedure, MR-A promises to become a valuable alternative to classical angiography in the diagnosis of MMD.

Verapamil and norverapamil plasma levels in infants and children during chronic oral treatment.

Verapamil and norverapamil trough plasma levels were measured in 22 children, aged from 15 days to 17 years, under chronic oral treatment with the drug (mean daily dose +/- SD: 4.9 +/- 1.4 mg/kg) for supraventricular tachyarrhythmias (n = 20) or hypertrophic cardiomyopathy (n = 2). Overall, 67 determinations were available (1 to 11 per patient) and the mean concentration values (+/- SD) were 43.3 +/- 36.4 ng/ml for verapamil and 41.7 +/- 28.9 ng/ml for norverapamil. Verapamil and norverapamil trough concentrations were correlated with the daily dose (p < 0.05) but a wide intersubject variability was present at any given dose and the regression line did not pass through the origin of axes (x-axis intercept: 1.2 mg/kg for verapamil, 0.9 mg/kg for norverapamil). To study the influence of age on drug kinetics, verapamil plasma concentrations corrected by daily dose/kg ([V]/D) and norverapamil to verapamil concentration ratios (N/V) (taken as an index of metabolic clearance) were divided according to age quartiles. The median [V]/D was higher in the first and in the fourth age quartile than in the other two age groups. On the contrary, median N/V ratio increased with age, suggesting that drug metabolism was improving during the first year of life. Four children developed typical adverse reactions to the drug (bradycardia, AV block, hypotension). In one case verapamil plasma levels were definitely high (294 ng/ml). In the other three cases, concomitant factors (such as very young age and heart disease) seem to have contributed to drug toxicity.

Respiratory mechanics in infants and young children before and after repair of left-to-right shunts.

In an attempt to investigate the relationship between respiratory mechanics and pulmonary hemodynamics, we evaluated pulmonary function in 31 infants with left-to-right shunts and subsequent high pulmonary blood flow, undergoing cardiac surgery. Measurements were performed 1 d before and repeated 10 d and 4-5 wk after correction. The age of the patients ranged from 4 d to 24 mo, body weight from 2.7 to 11.8 kg. Pulmonary artery pressure, assessed by Doppler echocardiography, was preoperatively elevated in 23 patients (group 1), whereas it was within normal values in eight infants (group 2). Respiratory mechanics were measured using the single-breath occlusion technique in sedated infants. To evaluate specific compliance, functional residual capacity was determined by using an open circuit nitrogen washout technique. A reduced preoperative compliance value (mean with 95% confidence interval) was found in group 1: 34.8 (26.5-43.1) mL.kPa-1. After hemodynamic correction, a progressive significant (p < 0.01) improvement was demonstrated at 10 d and 1 mo with values of 47.5 (39.2-55.8) mL.kPa-1 and 56.5 (45.6-67.4) mL.kPa-1, respectively. A similar trend was noted evaluating specific compliance with values of 0.27 (0.24-0.30) kPa-1 and 0.44 (0.42-0.46) kPa-1, respectively before and after surgery. Preoperative functional residual capacity value was 130 (100-160) mL. In group 2, normal preoperative compliance values were obtained, without significant changes after surgery. In both groups, resistance was within the normal range both before and after surgical correction, and functional residual capacity did not change either. No correlations were found between compliance and pulmonary artery pressure and pulmonary blood flow values.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler and 2D echocardiographic diagnosis of congenital coronary artery fistulae to the right cardiac chambers: report of 3 cases.

We present three cases of coronary artery fistulae to the right cardiac chambers. The first was a 2-day-old neonate in congestive heart failure: 2D and Doppler echocardiography revealed a dilated proximal left coronary artery and a fistulous connection to the right atrium. The other two patients, respectively 4 and 3 years old, were asymptomatic and presented with a continuous heart murmur: a left coronary artery fistula into the right ventricle was detected by ultrasound in one, and a dilated proximal right coronary artery in the other. The diagnosis was confirmed in all three patients. The first patient was operated upon at 18 months of age; the second patient is awaiting surgery, and in the third patient the fistula was ligated at the age of 3 years. The possibility of ultrasound diagnosis without invasive procedures is suggested.

Hyperthyroid-induced chorea in an adolescent girl.

Hyperthyroidism is invariably accompanied by nervous system dysfunctions. Irritability, emotional lability and hyperkinesia are the signs and symptoms most frequently observed. Chorea or choreoathetosis are only rarely associated with hyperthyroidism. It is the purpose of this work to describe the case of a young girl in whom chorea was the main manifestation of thyrotoxicosis. The chorea receded and disappeared as the patient became euthyroid. Hyperthyroidism, therefore, is to be considered an unusual cause of chorea and every patient with choreiform movements should be examined also for thyroid function.

Is lung biopsy useful for surgical decision making in congenital heart disease?

Sixty patients with congenital heart disease (CHD), age range 3 months-45 years (median 2 years), underwent lung biopsy to exclude pulmonary vascular disease (PVD): 25 had an atrioventricular (AV) septal defect, 14 a ventricular septal defect (VSD), 7 a complete transposition of the great arteries (TGA) + VSD, 3 an atrial septal defect, and 2 a patent ductus arteriosus; 9 had other malformations. Scoring of histological section (0-4) according to a modified Heath-Edwards classification disclosed that 30 patients had severe "irreversible" PVD (greater than or equal to grade 3) (11 AV septal defect, 8 VSD, 6 TGA + VSD and 5 others); 8 patients were younger than 1 year. Pulmonary vascular resistance (PVR) was calculated in 51 patients and exceeded 7 U/m2 in 1 of 2 patients with grade 0, in 9 of 18 with grade 1, in 1 of 4 with grade 2, in 11 of 18 with grade 3, and in 8 of 9 with grade 4. PVR was also calculated after 100% oxygen administration in 19 patients, 14 of whom had a resting PVR greater than or equal to 7 U/m2. PVR persisted greater than or equal to 7 U/m2 in 5 patients: 4 had PVD greater than or equal to grade 3 and died after surgery. PVR fell to under 7 U/m2 in 14 patients, 3 of whom had PVD greater than or equal to grade 3:1 patient with grade 4 was not operated upon and 2 with grade 3 were operated upon: all are alive. Follow-up in discharged living patients was 100%, with a mean of 50 months. Fifty-five patients underwent surgery with 10 early and 2 late deaths. Among the 12 subjects with a fatal outcome, 10 had irreversible lesions. The 5 non-operated patients all had irreversible lesions at biopsy, and are still alive.(ABSTRACT TRUNCATED AT 250 WORDS)

Steady-state serum concentrations of imipramine, its main metabolites and clinical response in primary enuresis.

Thirty-seven children (6-13 years old), receiving a flexible dosage of imipramine (IMI) for nocturnal enuresis, were evaluated. After a mean time of 8.5 +/- 7.0 weeks of therapy, 40.5% no longer wet the bed; 32.4% had a mean benefit of 80%; 27.01% had a negligible response. The best relationship observed was between clinical effect and drug serum concentrations rather than with drug daily dose, the most satisfactory being that with IMI seric values (P = 0.019). Responders (effect higher than 50%) had higher IMI serum concentrations (P less than 0.05) than poor responders. At 3 and 6 months after stopping the drug, over 90% of the responders maintained the maximum response reached during treatment. The side-effects observed were irritability, reduction of appetite, headache, a mild increase of blood pressure.

Radionuclide evaluation of lung perfusion after the Fontan procedure.

Lung perfusion was evaluated in 19 patients in whom a Fontan operation had been performed at a mean age of 3.7 years. First pass and equilibrium data were acquired during the lung particle perfusion scan 0.5 to 7.9 years (mean 3.7 years) following the Fontan procedure. Abnormalities of lung perfusion were documented in 8 patients. Minimal underperfusion of small areas of either right or left lung were noted in 4 patients, while the remaining 4 had evidence of major perfusion defects, involving both lungs. The perfusion defects were localized, in the majority of cases, on the side where a palliative procedure had been performed before the Fontan operation: it is of note that all our patients without palliative procedures did not show abnormalities in lung perfusion. Major abnormalities of lung perfusion seemed related to possible intimal thrombosis or emboli due to prolonged polycythemia or to pulmonary vessel distortion due to long-standing shunts.

Aspartate aminotransferase and alanine aminotransferase serum activities in neonatal transient myocardial ischemia.

The behavior of serum aspartate aminotransferase and alanine aminotransferase was evaluated during the first 30 postnatal days in 16 neonates with clinical, electrocardiographic and echocardiographic features of transient myocardial ischemia. These common laboratory tests, requested usually as an aid to diagnosis and surveillance of myocardial damage both in the adult and infant age groups, do not seem to have any value in the perinatal period compared to established reference values of healthy or asphyxiated controls.

Charcot-Marie-Tooth disease and cardiac arrhythmias.

A child with several episodes of supraventricular tachycardia was treated in our department from birth to the age of seven years. At this age a diagnosis of Charcot-Marie Tooth disease was made on the basis of the results of clinical and neurophysiological examinations, blood analysis and a neuromuscular biopsy. The association between sensorimotor neuropathies and cardiac involvement is controversial, especially at pediatric ages. We describe a case presenting this association.

Congestive heart failure secondary to cerebral arterio-venous fistula.

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.

Fatal paroxysmal supraventricular tachycardia in an infant.

A 37-day-old infant, without associated congenital anomalies, died following a 48-hour episode of supraventricular tachycardia. The histopathologic findings of nodoventricular and fasciculoventricular Mahaim's fibers in a setting of persistent fetal dispersion were consistent with an anatomic substrate for a reentry circuit at the specialized A-V junction.

Pulmonary atresia with intact ventricular septum: a quantitative cineventriculographic study of the right and left ventricular function.

Quantitative cineventriculographic measurements (ventricular volumes, ejection fraction, and myocardial mass) were obtained in 15 neonates with pulmonary atresia and intact ventricular septum. There was a wide dimensional range for the right ventricle, from a reduced through normal to enlarged. A restrictive tricuspid valve (less than 12 mm) was associated with a small or diminutive right ventricle. A normal function of the right ventricle was present only in those cases with normal-sized chambers. The left ventricular end-diastolic volume was always greater than normal. The ejection fraction was normal only if a normal myocardial mass was present. Additional abnormalities were frequent in the myocardium of both ventricles, such as extreme thinning of the wall of the right ventricle and hypoplasia or fibroelastosis of the left ventricle. All these factors can lead to a poor surgical prognosis despite good anatomical correction.

Abnormal pulmonary artery branching in tetralogy of Fallot with "absent" pulmonary valve.

Microangiographic postmortem study in a case of tetralogy of Fallot with so-called absent pulmonary valve disclosed an abnormal branching pattern of the intrapulmonary arteries, but failed to detect any compression of intrapulmonary bronchi as a consequence of the distorted segmental arteries. The case also featured the absence of the ductus arteriosus, which should be considered a basic associated anomaly in the development of this malformative complex.

[Syncope in childhood]. / Le sincopi in età pediatrica.

Syncope may be defined a sudden and transient loss of consciousness due to a reversible alteration of brain function. Three main groups of syncopes can be identified: cardiac, vascular and non-cardiovascular. All the patients (63) admitted to the emergency unit of Pediatric Clinic of the University of Padua from January 83 to July 84 and reporting one or more episodes of loss of consciousness were examined. Their age ranged from 1 month to 15 years. All the patients were investigated with the same study protocol: ECG, EEG, 24 hours ECG monitoring, routine blood examinations; other tests were done when needed. The cause of syncope was established in 53,8% of cases; for 6,3% of patients the cause was cardiac (arrhythmic), in 38% it was vascular (vasovagal syncope), in 6,3% it was non-cardiovascular (neurologic or metabolic). The cause of syncope was not identified in 46% of the patients, which is also in agreement with other studies. However, we were able, through the use of our protocol, to identify quickly and non invasively the etiology of the syncope in 25% of the patients.

Cytochrome b5 reductase activity in erythrocytes and leukocytes as related to sex and age.

We measured cytochrome b5 reductase (EC 1.6.2.2) activity in erythrocytes and leukocytes from subjects of both sexes ranging in age from neonate to adulthood, all either apparently healthy or without hematologic disorders. The activities were determined spectrophotometrically (J. Lab. Clin. Med. 72: 339-344, 1968). Within-run precision (CV) of the reductase determination was 6.4% and 3.7% for erythrocytes and leukocytes, respectively. Activity in either erythrocytes or leukocytes was unrelated to sex. Activity was lowest in erythrocytes of newborns (p less than 0.001) but reached adult values within the first postnatal year. Leukocyte activity was higher (p less than 0.05) in infants one to 24 months old than in other groups, possibly because of variations in leukocyte count in the first postnatal months.