Causes of sudden unexpected cardiac death in the first two decades of life

Sudden, unexpected cardiac death in the age group 1 to 21 years usually is due to myocarditis, hypertrophic cardiomyopathy, aortic valvar stenosis, and coronary arterial abnormalities. The hearts of 70 patients <21 years of age who died suddenly were reviewed. Twenty patients were <1 year of age and 50 were 1 to 21 years old. The cardiac findings were compared with those in 68 age-matched controls with known cardiac disease who did not die suddenly. Significant cardiac abnormalities were present in 13 (65%) of the 20 infants; 10 (50%) had anomalies of the aortic origin of the coronary arteries. Among the 50 older patients, cardiac abnormalities were found in 40 (80%), among whom coronary arterial anomalies existed in 12 (24%). Anomalies of aortic origin more frequently involved the left main than the right coronary artery in both groups.     

Atopic sensitization during the first year of life in relation to long chain polyunsaturated fatty acid levels in human milk

The influence of low (0.39-1.1%), medium (4.25%) and high (7.1-32.5%) fat levels in fish on radiation inactivation of four food-borne pathogens was investigated. Cells of Listeria monocytogenes 036, Yersinia enterocolitica F5692, Bacillus cereus and Salmonella typhimurium at logarithmic phase were inoculated in 10% fish homogenates and subjected to gamma irradiation at ice temperature (0-1 degree C) with doses ranging from 0.05 to 0.8 kGy. The radiation survival curves of L. monocytogenes and B. cereus were characterized by shoulders, while a tailing effect was depicted by cells of Y. enterocolitica and B. cereus. The D10 values in kGy calculated on the exponential part of the curve ranged from 0.2 to 0.3, 0.15 to 0.25, 0.1 to 0.15 and 0.09 to 0.1 for L. monocytogenes 036, B. cereus, Salm. typhimurium and Y. enterocolitica F5692, respectively. This order (D10) of radiation resistance of each organism was not affected by the fat content of the fish. Inoculated pack studies carried out separately with each pathogen in fatty (Indian sardine, 7.1%) and lean (Golden anchovy, 0.39%) fish showed no difference in their survival after exposure to 1 kGy and 3 kGy doses, which corroborated the above observation. The practical significance of these results in the application of the technology is discussed.     

Candida endocarditis in the first year of life

Candida is an increasing problem as a causal agent of nosocomial infection in neonates and infants. We report 15 cases of infective endocarditis caused by Candida spp treated at the Hospital Infantil de Mexico between 1980 and 1991. The diagnosis of endocarditis was established by the identification of Candida in at least two blood cultures and echocardiographic assessment. From 110 cases of systemic candidiasis during the eleven years period of study, fifteen patients presented endocarditis (13.6%), all had a central venous catheter. Three had antecedent of congenital heart disease. Candida isolation was obtained an average of 28 days after admission. The major clinical findings were: fever in 13 patients, respiratory distress and cardiac murmurs observed in nine respectively. Thrombocytopenia was present in eight children. The echocardiographic evaluation showed vegetations located in the superior vena cava in six, right atrium in five, tricuspid valve in two, inferior vena cava and right ventricle in one respectively. Three cases were subjected to surgical treatment. Nine patients died for a case fatality rate of 60%. The echocardiographic evaluation practiced in all patients with suspicion of systemic candidiasis is critical for the prognosis. The identification of endocardiac involvement coupled with the opportune administration of antifungal therapy and surgical treatment may improved the survival.     

Accommodative esotropia during the first year of life

Two infants developed accommodative esotropia during their first six months of life. One infant, whose age at onset was 4 1/2 months, had 4.50 diopters of hyperopia. The second infant, whose age at onset was 5 months, had 3.50 diopters of hyperopia. In both infants, the eyes completely aligned with hyperopic correction. Two points are stressed. First, when the amount of hyperopia exceeds +3.00, consideration should be given to an accommodative element as the cause of the esotropia, even if the child is only 4 to 6 months old. Second, even with small angles of esotropia, an accommodative element should be considered, if there is a substantial amount of hyperopia.     

Study on the organ weight of sudden death cases

The progressive B-cell destruction at the onset of type 1 diabetes and the relevance of residual B-cell function to metabolic control prompted us to try to prevent further B-cell destruction in new-onset type 1 diabetic patients. Having already shown positive effects of sulfonylreas in long-standing IDDM patients, we decided to try the association of gliclazide with insulin in newly diagnosed IDDM patients. Therefore, 22 patients were randomly assigned to either gliclazide, 160 mg/24 h, or placebo (in association with standard insulin treatment) from the third week since the onset of the disease. Patients were studied every 6 months for 18 months. The insulin need was similar in the two groups at time 0, but thereafter it steadily decreased in the GCZ group becoming at 6, 12 and 18 months, respectively 65%, 42% and 39% of that of the PL group. The metabolic control was very similar in the two groups throughout the study. The residual B-cell function (fasting and post-breakfast C peptide), which was similar in the two groups at time 0, remained unchanged or improved in the GCZ group, whereas it decreased in the PL group. In conclusion, the combined insulin-gliclazide treatment appeared to improve B-cell function during the first 18 months of type 1 diabetes, inducing a major reduction of the insulin need with respect to patients treated with insulin alone.     

High postmortem concentrations of hypoxanthine and urate in the vitreous humor of infants are not confined to cases of sudden infant death syndrome

OBJECTIVE: High concentrations of hypoxanthine and urate have been found in the blood of rats who died suddenly during induced respiratory alkalosis as well as in cases of sudden death in malignant hyperthermia-susceptible pigs challenged with halothane. The origin of these metabolites is the excessive hydrolysis of adenine nucleotides, which is associated with the production of free radicals. We wished to establish whether high levels of these compounds were also to be found in sudden infant death syndrome (SIDS) victims, compared with other causes of death. DESIGN: Vitreous humor samples were analysed for hypoxanthine and urate by high-performance liquid chromatography. SETTING: Forensic Laboratories, Salt River, Cape Town. PARTICIPANTS: Vitreous humor samples were collected from 91 infants presented for postmortem examination. MAIN OUTCOME AND RESULTS: From autopsy reports, cause of death was classified as: (i) SIDS (N = 50); (ii) acute sudden death (N = 5); and (iii) all other causes of death (N = 36). There were no differences in the hypoxanthine or urate levels of groups (i) and (iii) over the first 5 days of the postmortem period. Group (ii) levels were lower than those of both (i) and (iii). CONCLUSION: Adenine nucleotide hydrolysis is not only a feature of SIDS, and possibly results from antemortem hypoxia in most deaths. The lower concentrations found in cases of acute sudden death probably resulted only from postmortem hydrolysis of the nucleotides.     

Morphological and biochemical changes in the myocardium after sudden death from ischemic heart disease

The myocardium was examined in 44 persons who had suddenly died of ischemic heart disease, in 37 who had died of injury, and in 28 who had died of alcohol poisoning. Those with ischemic heart disease had foci of necrosis of the muscle fibers, severe disturbances in microcirculation, changes in the activity of certain myocardial enzymes and in the content of lipids in the myocardium. Biochemical changes similar to these in many respects were revealed in individuals who had died of alcohol poisoning, in view of which alcohol poisoning may be a factor conducive to sudden death in ischemic heart disease.     

Respiratory mechanics of the horse during the first year of life

This study investigated the developmental changes in the mechanical properties of the respiratory system in growing horses. Pulmonary mechanics and lung volumes were serially measured in anesthetized foals during the first year of life. Quasi-static pressure-volume curves were generated, and functional residual capacity (FRC) was measured using a closed nitrogen equilibration technique. At birth, chest wall compliance normalized to body weight was substantially less than that reported in other less precocious newborn species, while lung compliance normalized to body weight was similar to values reported for other species. Characteristics of the transition from the neonatal to adult respiratory system in the foal included a decrease in the ratios of chest wall to lung compliance (Cw/CL) and the unstressed volume of the chest wall to TLC, and a constant FRC/TLC throughout most of the study period. The somatic growth of the foal and its respiratory system were uneven processes, with increases in lung volume lagging increases in overall body size.     

Blood pressure levels of preterm infants in the first year of life

Systolic blood pressure was measured in 36 infants with median gestational age of 29 weeks (range 24-35 weeks) and birth weight of 1160 g (range 642-1500 g). Measurements were made at 1, 6 and 12 weeks, and subsequently at 12-weekly intervals during the first year of life. No infant developed chronic lung disease. Systolic blood pressure increased over the first 24 weeks (p < 0.001) to a mean value of 95 mmHg, but did not change significantly over the next 24 weeks. These data provide a reference range of blood pressure levels during the first year of life for infants born at an early gestational age.     

Changes in cerebrospinal fluid monoamine metabolites, tryptophan, and gamma-aminobutyric acid during the 1st year of life in normal infants. comparison with victims of sudden infant death syndrome

Cerebrospinal fluid (CSF) levels of 3-methoxy-4-hydroxyphenylglycol, 5-hydroxyindoleacetic acid, homovanillic acid, tryptophan, and gamma-aminobutyric acid were measured using high-performance liquid chromatography in 102 infants during the 1st year of life (preterm and term neonates included). CSF levels are expressed versus corrected age (postnatal days - preterm days) which reflects the stage of maturity of the central nervous system. These results are compared to those obtained in CSF of 53 victims of sudden infant death syndrome (SIDS). All components were significantly higher in SIDS than in the age-matched control group. This increase does not seem to be an artefact related to death. Indeed, under the same conditions concerning postmortem time interval before CSF sampling and analysis, the levels are not significantly higher in infants who died from a known pathology than in living infants. Moreover, in living infants as regards a pathology such as asphyxia or hypoventilation in comparison with SIDS, similar profiles are observed in some neurotransmitters or metabolites. Other studies are necessary to explore further neurotransmission systems in SIDS.     

Nasopharyngeal colonization in Costa Rican children during the first year of life

BACKGROUND: The establishment of the nasopharyngeal flora was followed in Costa Rican children from birth to 1 year of age. METHODS: Nasopharyngeal cultures were obtained at 1 (n = 413), 3 (n = 393), 6 (n = 376) and 12 months (n = 356) of age from children representative of the population in the Puriscal district. Weekly cultures were obtained from a subcohort of these children (n = 101). Mother-infant diads (n = 95) and preschool children (n = 208) attending day-care centers were also studied. RESULTS: The estimated proportion of colonized children in the population differed markedly depending on the frequency of culture. Quarterly cultures showed a slow increase in carrier rates from 3.9% for Haemophilus influenzae, 3.1% for Streptococcus pneumoniae and 6.5% for Moraxella catarrhalis at 1 month of age to 10.1% carrying H. influenzae and 19.4% carrying S. pneumoniae by the end of the first year. By quarterly culture the proportion of children colonized at least once was 36% for S. pneumoniae, 26% for H. influenzae and 28% for M. catarrhalis. In contrast weekly sampling showed that 95 to 100% of the children were colonized at least once during the first year of life with H. influenzae, S. pneumoniae or M. catarrhalis. Nasopharyngeal carriage of H. influenzae, S. pneumoniae and M. catarrhalis was low in the mothers, and very few mother-infant pairs carried identical bacteria at the same time. In contrast carrier rates were high in the siblings attending day care (H. influenzae 27.9%, S. pneumoniae 39.4%, both organisms 26.6%). Infants with siblings had significantly higher bacterial carriage at all ages than infants without siblings. CONCLUSIONS: Quarterly nasopharyngeal cultures showed that Costa Rican infants acquire their nasopharyngeal flora at a rate comparable with that for infants in developed countries and that siblings are an important source of the bacteria. Weekly samplings showed that virtually all children were colonized at least once during the first year of life.     

Patterns of eye–hand coordination in the first year of life.

The traditional reflex-to-voluntary behavior model of development is questioned, and an alternative hypothesis is proposed that reflex functions are distinct from the ontogenetic antecedents of voluntary behavior. An overview of patterns of eye–hand coordination in the 1st yr of life suggests that reflexes and cortically controlled instrumental activity share a parallel course of development, with the latter increasing in frequency and importance as development proceeds. Despite procedural problems in studying neonatal reaching there remains sufficient evidence that hand movements in infants under 8 wks of age are progressively coordinated with visual stimuli. Some new data are presented that show that up to at least 12 wks of age the left hand shows greater activity and orientation to visual stimuli than the right hand, which is contralateral to the dominance of neonatal reflexes. Experiments are reviewed that have studied the emergence of visually guided reaching and its development during the 2nd half of the 1st yr. The evidence is consistent with the hypothesis that this apparently new behavior, clearly distinct from reflexes, is in fact on a continuum with these earlier nonreflexive, instrumental behaviors. (French abstract) (79 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Morbidity during the first year of life in small for gestational age infants

OBJECTIVE: To study the effect of early postnatal dexamethasone (days 1-3) on the incidence and severity of chronic lung disease in preterm infants with respiratory distress syndrome. METHODS: A multicentre, randomised, placebo controlled, blinded study was carried out in 18 neonatal intensive care units in Israel. The primary outcome measure was survival to discharge without requirement for supplemental oxygen therapy beyond 28 days of life. The secondary outcome measures were requirement for mechanical ventilation at 3 and 7 days, duration of ventilation or oxygen therapy, need for subsequent steroids for established chronic lung disease and incidence of major morbidities. RESULTS: The study consisted of 248 infants (dexamethasone n = 132; placebo n = 116). No differences were found in the outcome variables except for a reduction in requirement for mechanical ventilation at age 3 days in treated infants (dexamethasone 44%, placebo 67%; P = 0.001). Gastrointestinal haemorrhage, hypertension, and hyperglycaemia were more common in treated infants, but no life threatening complications, such as gastrointestinal perforation, were encountered. CONCLUSIONS: These data do no support the routine use of early postnatal steroids, but may justify further study in a selected, high risk group of infants.     

Vitamin E and C levels in infants during the first year of life

The considerably lower vitamin E level found in cord blood and in newborns at birth than those found in the venous blood of mothers at delivery are not yet fully explained. In a group of 217 not selected newborns, we attempted to establish the relation between vitamin E and C levels at delivery and the changes during the first year of life. The mean serum vitamin E level rose from 0.37 mg/ml at 3 days to 0.80 mg/100 ml at 6 months and to 0.72 mg/100 ml at 12 months. On the other hand vitamin C mean levels lowered from 0.93 mg/100 ml in cord blood to 0.77 mg/100 ml at 6 months and to 0.73 mg/100 ml at 12 months. The rise of vitamin E values could be explained by the early use of infant solid foods with high vitamin and mineral content and by the increase of serum lipoproteins. Except at 3 days after delivery there were no individual values of serum vitamin E below the acceptable 0.35 mg/100 ml limit. However, serum vitamin C levels compatible with a moderate risk were very often observed, i.e., in 27.1% of infants at 6 months and in 30.5% at 1 year. Thus, vitamin E intake in infants was satisfactory with the usual diet but not vitamin C for which blood levels were not adequate. In view of these findings it appears necessary to evaluate periodically the vitamin E as well as vitamin C status in the infant population.     

Prevention of ischemia-induced cardiac sudden death by n-3 polyunsaturated fatty acids in dogs

The objective of this study was to obtain functional information associated with the prevention by n-3 polyunsaturated fatty acids (PUFA) of ischemia-induced fatal cardiac ventricular arrhythmias in the intact, conscious, exercising dog. Thirteen dogs susceptible to ischemia-induced ventricular fibrillation were prepared surgically by ligation of their anterior descending left coronary artery and placement of an inflatable cuff around their left circumflex artery. After 4 wk of recovery, exercise-plus-ischemia tests were performed without and then with an intravenous infusion of an emulsion of free n-3 PUFA just prior to occluding the left circumflex artery while the animals were running on a treadmill. One week later the exercise-plus-ischemia test was repeated but with a control infusion replacing the emulsion of n-3 PUFA. The infusion of the free n-3 PUFA in quantities of 1.0 to 10 g prevented ventricular fibrillation in 10 of the 13 dogs tested (P < 0.005), apparently without esterification of the PUFA into membrane phospholipids. The antiarrhythmic effect of the n-3 PUFA was associated with slowing of the heart rate, shortening of the QT-interval (electrical action potential duration), reduction of left ventricular systolic pressure, and prolongation of the electrocardiographic atrial-ventricular conduction time (P-R interval). These effects are comparable with those we have reported in studies with cultured neonatal rat cardiac myocytes.     

Psychophysiological correlates of emotional reactivity during the first year of life.

Emotional reactivity is an important dimension thought to underlie individual differences in infant temperament. In a series of studies, we have examined the relation between behaviors reflecting this dimension and measures of heart rate variability. In the current study, longitudinal behavioral data on two groups of infants selected for their pattern of heart period variability are presented: those with high vagal tone (high heart rate variability) and those with low vagal tone (low heart rate variability) at 14 months of age. The data suggest that infants with high vagal tone were more reactive to both positive and negative events at 5 months and more sociable and approachful at 14 months. Infant reactivity to mildly stressful events seems to be a stable dimension during the first year, and there is a strong association between differences in reactivity and the degree to which the autonomic nervous system is influenced by vagal tone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)