Paleogene Ficus leaves from India and their implications for fig evolution and diversification.

PREMISE: Ficus is a scientifically and economically important genus with abundant fossil records from the Paleocene to Pleistocene, but with an intriguing early evolutionary history that remains unresolved. Here, the foliage of three well-preserved figs is described from the early Paleogene succession of the Gurha mine, Rajasthan, India. These fossils provide new morphological data that strengthens our understanding of the past occurrences of Ficus and, alongside all validly published records of fossil figs, helps to trace the evolutionary history of figs. METHODS: Fossils were identified and described by comparison with their closest modern analogs using the Nearest Living Relative (NLR) technique. Validated fig records are listed and categorized into six geological time frames. Modern precipitation data for the current distributions of NLRs were downloaded from the Climatic Research Unit Timeseries. RESULTS: Fossil leaves assigned to three new species Ficus paleodicranostyla, F. paleovariegata, and F. paleoauriculata closely resemble their modern analogs based on leaf morphology. Reliable fossil records were used to hypothesize historical fig distributions and paleodispersal pathways. Precipitation data suggest higher precipitations at the fossil locality during the early Paleogene than at present. CONCLUSIONS: The fossils described herein supplement fig fossil records known from other regions indicating that figs were widely diverse across low latitudes by the early Paleogene. These data support a Eurasian origin for figs, highlight a pivotal role for the Indian subcontinent during the early phase of fig diversification, and depict a perhumid-to-humid climate with high rainfall concordant with paleoclimate evidence from the Gurha mine.

Permutation/randomization-based inference for environmental data.

Quantitative inference from environmental contaminant data is almost exclusively from within the classic Neyman/Pearson (N/P) hypothesis-testing model, by which the mean serves as the fundamental quantitative measure, but which is constrained by random sampling and the assumption of normality in the data. Permutation/randomization-based inference originally forwarded by R. A. Fisher derives probability directly from the proportion of the occurrences of interest and is not dependent upon the distribution of data or random sampling. Foundationally, the underlying logic and the interpretation of the significance of the two models vary, but inference using either model can often be successfully applied. However, data examples from airborne environmental fungi (mold), asbestos in settled dust, and 1,2,3,4-tetrachlorobenzene (TeCB) in soil demonstrate potentially misleading inference using traditional N/P hypothesis testing based upon means/variance compared to permutation/randomization inference using differences in frequency of detection (Δf d). Bootstrapping and permutation testing, which are extensions of permutation/randomization, confirm calculated p values via Δf d and should be utilized to verify the appropriateness of a given data analysis by either model.

Uncertainty in predictions of the climate response to rising levels of greenhouse gases.

The range of possibilities for future climate evolution needs to be taken into account when planning climate change mitigation and adaptation strategies. This requires ensembles of multi-decadal simulations to assess both chaotic climate variability and model response uncertainty. Statistical estimates of model response uncertainty, based on observations of recent climate change, admit climate sensitivities--defined as the equilibrium response of global mean temperature to doubling levels of atmospheric carbon dioxide--substantially greater than 5 K. But such strong responses are not used in ranges for future climate change because they have not been seen in general circulation models. Here we present results from the 'climateprediction.net' experiment, the first multi-thousand-member grand ensemble of simulations using a general circulation model and thereby explicitly resolving regional details. We find model versions as realistic as other state-of-the-art climate models but with climate sensitivities ranging from less than 2 K to more than 11 K. Models with such extreme sensitivities are critical for the study of the full range of possible responses of the climate system to rising greenhouse gas levels, and for assessing the risks associated with specific targets for stabilizing these levels.

Infantile cardiomyopathy caused by a mutation in the overlapping region of mitochondrial ATPase 6 and 8 genes.

BACKGROUND: Infantile cardiomyopathy is a genetically heterogeneous disorder with significant morbidity and mortality. METHODS: This study aimed to identify the mutation present in four unrelated patients who presented as infants with isolated hypertrophic cardiomyopathy. RESULTS: In all four, a novel mitochondrial m.8528T-->C mutation was identified. This results in a change of the initiation codon in ATPase 6 to threonine and a concurrent change from a highly conserved hydrophobic amino acid, tryptophan, at position 55 of ATPase 8 to a highly basic arginine. To our knowledge, this is the first report of a mutation affecting both mitochondrial genome-encoded complex V subunit proteins. Testing of the relatives of one patient indicated that the mutation is heteroplasmic and correlated with disease. CONCLUSION: Mitochondrial genome sequencing should be considered in patients with infantile hypertrophic cardiomyopathy.

Assessing background particulate contamination in an historic building - surface lead loading and contamination.

Investigation of suspect surface contamination in a building may require comparative sampling across different zones to provide meaningful information with regard to contaminant sources, pathways and/or extent of dispersal. However, evaluation of the data using traditional null hypothesis significance testing (NHST) based upon the mean may result in misleading inference when encountering erratic distributions typical of environmental contaminant data. Sampling data (n = 90) for lead content in surface dust collected throughout a historic building with suspect contamination from uncontrolled disturbance to lead coatings were evaluated using traditional NHST and randomization/permutation inference; the latter metric was the maximum difference in frequency of detection (Δfd max), to directly calculate the probability of the observed differences. In the examples for lead in surface dust presented herein, areas with "lower" mean concentration and/or no significant difference via NHST actually represented "greater contamination," as Δfd max indicated a greater probability of encountering lead at higher concentrations. Resulting conclusions with regard to sources and pathways contradicted those generated from traditional NHST, and underscore the need to recognize differences in applicability of different inference approaches, depending upon the distribution of the data and the particular problem. This is particularly relevant for forensic purposes. IMPLICATIONS: The use of permutation/randomization inference to gain insight into sources and pathways of contamination may be more appropriate than the conventional Neyman/Pearson (N/P) logic in negative hypothesis significance testing (NHST). This suggests a broader understanding by environmental professionals of the assumptions and limitations of NHST and alternative inference such as through permutation/randomization is warranted.

Evidence of fungal decay in petrified legume wood from the Neogene of the Bengal Basin, India.

Silicified fossil legume woods of Cynometroxylon Chowdhury & Ghosh collected from the Neogene (late Miocene) sediments of the Bengal Basin, eastern India, exhibit fungal decay seldom found in the fossil record. The wood possesses numerous perforate areas on the surface that seem to be the result of extensive fungal activity. In transverse section, the decayed areas (pockets) appear irregular to ellipsoidal in outline; in longitudinal section these areas of disrupted tissue are somewhat spindle-shaped. Individual pockets are randomly scattered throughout the secondary xylem or are restricted to a narrow zone. The aforesaid patterns of decay in fossil wood show similarities with that of white rot decay commonly produced by higher fungi, specifically basidiomycetes and ascomycetes. The host fossil wood harbors abundant ramifying and septate fungal hyphae with knob like swellings similar to pseudoclamps in basidiomycetes, and three-celled conidia-like reproductive structures. This record expands our current knowledge of wood decaying fungi-host plant interaction in the Neogene tropical forests of Peninsular India.

Dinosaurs on the north slope, alaska: high latitude, latest cretaceous environments.

Abundant skeletal remains demonstrate that lambeosaurine hadrosaurid, tyrannosaurid, and troodontid dinosaurs lived on the Alaskan North Slope during late Campanian-early Maestrichtian time (about 66 to 76 million years ago) in a deltaic environment dominated by herbaceous vegetation. The high ground terrestrial plant community was a mild- to cold-temperate forest composed of coniferous and broad leaf trees. The high paleolatitude (about 70 degrees to 85 degrees North) implies extreme seasonal variation in solar insolation, temperature, and herbivore food supply. Great distances of migration to contemporaneous evergreen floras and the presence of both juvenile and adult hadrosaurs suggest that they remained at high latitudes year-round. This challenges the hypothesis that short-term periods of darkness and temperature decrease resulting from a bolide impact caused dinosaurian extinction.

No high Tibetan Plateau until the Neogene.

The Late Paleogene surface height and paleoenvironment for the core area of the Qinghai-Tibetan Plateau (QTP) remain critically unresolved. Here, we report the discovery of the youngest well-preserved fossil palm leaves from Tibet. They were recovered from the Late Paleogene (Chattian), ca. 25.5 ± 0.5 million years, paleolake sediments within the Lunpola Basin (32.033°N, 89.767°E), central QTP at a present elevation of 4655 m. The anatomy of palms renders them intrinsically susceptible to freezing, imposing upper bounds on their latitudinal and altitudinal distribution. Combined with model-determined paleoterrestrial lapse rates, this shows that a high plateau cannot have existed in the core of Tibet in the Paleogene. Instead, a deep paleovalley, whose floor was <2.3 km above mean sea level bounded by (>4 km) high mountain systems, formed a topographically highly varied landscape. This finding challenges prevailing views on tectonic processes, monsoon dynamics, and the evolution of Asian biodiversity.

Pediatric restrictive cardiomyopathy associated with a mutation in beta-myosin heavy chain.

Most children do not have a known cause of cardiomyopathy which limits the potential for disease-specific therapies. Of the different phenotypic presentations of cardiomyopathy, the restrictive form carries the poorest prognosis and has the lowest rate of identification of etiology. We present the first description of a beta-myosin heavy chain gene mutation in an infant with restrictive cardiomyopathy requiring cardiac transplantation. As demonstrated by three-dimensional protein structure modeling, the missense mutation is in a highly conserved amino acid at the critical binding region for the essential light chain. This case emphasizes that mutations in sarcomeric proteins, which are known to cause hypertrophic cardiomyopathy in adults, may be associated with the development of restrictive physiology in childhood. Identification of the genetic basis of pediatric cardiomyopathy has important implications for management and genetic counseling.

Verifying interpretive criteria for bioaerosol data using (bootstrap) Monte Carlo techniques.

A number of interpretive descriptors have been proposed for bioaerosol data due to the lack of health-based numerical standards, but very few have been verified as to their ability to describe a suspect indoor environment. Culturable and nonculturable (spore trap) sampling using the bootstrap version of Monte Carlo simulation (BMC) at several sites during 2003-2006 served as a source of indoor and outdoor data to test various criteria with regard to their variability in characterizing an indoor or outdoor environment. The purpose was to gain some insight for the reliability of some of the interpretive criteria in use as well as to demonstrate the utility of BMC methods as a generalized technique for validation of various interpretive criteria for bioaerosols. The ratio of nonphylloplane (NP) fungi (total of Aspergillus and Penicillium) to phylloplane (P) fungi (total of Cladosporium, Alternaria, and Epicoccum), or NP/P, is a descriptor that has been used to identify "dominance" of nonphylloplane fungi (NP/P > 1.0), assumed to be indicative of a problematic indoor environment. However, BMC analysis of spore trap and culturable bioaerosol data using the NP/P ratio identified frequent dominance by nonphylloplane fungi in outdoor air. Similarly, the NP/P descriptor indicated dominance of nonphylloplane fungi in buildings with visible mold growth and/or known water intrusion with a frequency often in the range of 0.5 Fixed numerical criteria for spore trap data of 900 and 1300 spores/m(3) for total spores and 750 Aspergillus/Penicillium spores/m(3) exhibited similar variability, as did ratios of nonphylloplane to total fungi, phylloplane to total fungi, and indoor/outdoor ratios for total fungal spores. Analysis of bioaerosol data by BMC indicates that numerical levels or descriptors based on dominance of certain fungi are unreliable as criteria for characterizing a given environment. The utility of BMC analysis lies in its generalized application to test mathematically the validity of any given descriptor or criterion for bioaerosols, which can be an important tool in quantifying the uncertainty in interpreting bioaerosol data.

Hereditary sacrococcygeal teratoma--not the same as its sporadic counterpart!

Sacrococcygeal teratoma (SCT) can be sporadic or familial and there appear to be different characteristics to these entities. It can be an isolated anomaly or occur as part of the Currarino triad, when it is associated with anorectal malformations and sacral anomalies. We present a case of familial sacrococcygeal teratoma and discuss its relationship to previously published reports, drawing conclusions regarding embryogenesis, diagnosis, screening and management.

Conservative treatment for girls with nonmetastatic rhabdomyosarcoma of the genital tract: A report from the Study Committee of the International Society of Pediatric Oncology.

PURPOSE: To report the results of a conservative multimodal approach in girls with nonmetastatic rhabdomyosarcoma (RMS) of the genital tract, treated in International Society of Pediatric Oncology (SIOP) Malignant Mesenchymal Tumors 84 and 89 protocols. PATIENTS AND METHODS: From 1984 to 1994, 38 girls with RMS of the genital tract (vulva, vagina, uterus) were treated in SIOP protocols. With the exception of patients with rare small tumors, which were resected at the start of the studies, all patients received initial chemotherapy (CHT) (ifosfamide, vincristine, and actinomycin D). Local treatment including surgery, brachytherapy (BT), and external-beam radiotherapy (ERT) was given only to girls who did not achieve complete remission (CR) with CHT or who subsequently relapsed. RESULTS: The primary tumor originated in the vulva or vagina in 27 girls and in the uterus in 11. The overall survival rate (+/- SE) was 91% +/- 6% at 5 years, and the event-free survival rate was 78% +/- 7%. At a median follow-up of 5 years, 30 girls were alive and in first CR and five were alive and in second CR. Four patients treated with complete resection of the tumor at diagnosis received less CHT. Thirteen patients were treated with CHT alone. In 17 patients, local treatment was necessary to achieve complete local control, for a residual mass after initial CHT (10 patients), for viable tumor on biopsy (three patients), or for local relapse (four patients). The local treatment used was radiotherapy (RT) (ERT in three patients, BT in seven), radical surgery with uterine ablation (three patients), RT and radical surgery (three patients), and conservative surgery with RT (one patient). CONCLUSION: Girls with nonmetastatic RMS of the genital tract have an excellent prognosis. We found no difference in outcome between uterine and vulvovaginal RMS. Local treatment does not seem necessary in patients who have a complete response to CHT. When a local treatment is needed, BT may be an alternative to radical surgery or ERT.

Percutaneous balloon angioplasty for native coarctation of the aorta.

Twenty-six children, aged 5 weeks to 14.7 years, underwent percutaneous balloon angioplasty for a discrete native coarctation of the aorta. The procedure reduced the systolic coarctation gradient acutely in all children. The mean systolic gradient decreased by 75%, from 48.6 +/- 2.4 before to 12.3 +/- 1.9 mm Hg after angioplasty (p less than 0.001). Long-term results were evaluated in 14 children by follow-up catheterization 12 to 26 months (mean 15.3) after angioplasty. At follow-up, the residual gradient averaged 11.7 +/- 3.7 mm Hg (range -5 to 36) and had not changed from that measured immediately after angioplasty (p = 0.64). Compared with preangioplasty values, the systolic pressure in the ascending aorta had improved substantially at follow-up (116.0 +/- 3.2 versus 143.9 +/- 3.1 mm Hg, p less than 0.001). On the basis of follow-up data, two groups of children were identified: Group 1 consisted of nine children with a good result, defined as a residual gradient less than 20 mm Hg and no aneurysm; Group 2 consisted of five children with a poor result, four with a residual gradient greater than 20 mm Hg (range 25 to 36) and one with an aneurysm at the dilation site. There was no statistical difference between the two groups in age at angioplasty, balloon size, ratio of balloon to isthmus diameters, follow-up duration, heart rate or cardiac output. However, of the four children with a residual gradient greater than 20 mm Hg, two were the youngest in the study, and in two the aorta was inadvertently dilated with a balloon 4 to 5 mm smaller than the isthmus diameter.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous closure of the small patent ductus arteriosus using occluding spring coils.

OBJECTIVES: This report summarizes our experience with the use of occluding spring coils to close the small patent ductus arteriosus. BACKGROUND: Several patent ductus arteriosus occluders (most notably the Rashkind device) have been developed and studied. Occluding spring coils have been used to close abnormal vessels and vascular connections. We previously reported the use of occluding spring coils to close the small patent ductus arteriosus in a small group of patients. This report describes our series of patients having patent ductus arteriosus closure with occluding spring coils. METHODS: Between June 1990 and June 1993, 30 patients underwent cardiac catheterization to have patent ductus arteriosus closure by occluding spring coils. Selection criteria were age > 6 months and narrowest patent ductus arteriosus internal dimension < or = 3.0 mm by color flow imaging. Definitive selection was based on review of aortograms performed at catheterization. A 5.2F coronary catheter was used to deliver one or two standard occluding spring coils. A loop was delivered in the main pulmonary artery, and the remainder of the coil was delivered across the patent ductus arteriosus and into the aortic diverticulum. Patent ductus arteriosus closure was confirmed by aortography or color flow imaging, or both. Follow-up after coil placement occurred at 6 weeks and 6 months and included two-view chest radiography, echocardiography and color flow imaging. RESULTS: Of the 30 patients, 29 had successful implantation by one (27 patients) or two (2 patients) occluding spring coils. Of these 29 patients, 19 had a clinically apparent and 10 had a silent patent ductus arteriosus. Average ductus minimal internal dimension was 1.7 mm (range 1.0 to 3.0). Complete closure of the ductus was confirmed in 27 patients by aortography or color flow imaging or both (in 24 within 4 h, in 2 after 6 weeks and in 1 after 6 months). Six weeks after implantation, two patients had a tiny residual patent ductus arteriosus noted on color flow imaging. One patient did not have successful implantation. This patient had a 3.2-mm ductus, and two coils migrated to the distal left pulmonary artery and could not be retrieved. There were no deaths or any significant complications noted during early or late follow-up in these patients. CONCLUSIONS: Occluding spring coils may have additional application in closing the small patent ductus arteriosus.

Quinidine syncope in children.

Quinidine syncope and factors associated with it are well known among adult patients treated for cardiac arrhythmias. To define factors that may influence the occurrence of syncope in children taking quinidine, the clinical, anatomic, electrocardiographic, roentgenographic and pharmacologic data were compared in six patients with syncope (Group A) and 22 patients without syncope (Group B). There was a significant (chi-square = 10.2, p = 0.001) relation between heart disease and quinidine syncope: all six Group A (syncopal) patients had heart disease whereas 15 of the 22 Group B (non-syncopal) patients had no structural heart disease. In contrast, no significant difference was noted between Group A and Group B patients in mean age (11.4 versus 11.4 years), mean quinidine serum concentration (2.9 versus 2.3 micrograms/ml), mean corrected QT interval before quinidine (0.43 versus 0.40 second) or mean corrected QT interval during quinidine therapy (0.46 versus 0.46 second) or between those taking digitalis and those not. Two of the six Group A (syncopal) patients died during therapy, one 6 days after initiating therapy and one suddenly at home 6 months after beginning quinidine. Another two of the six Group A patients exhibited hypokalemia (both 2.9 mEq/liter) at the time of syncope, 2 weeks and 6 months, respectively, after initiation of quinidine therapy; both survived. Syncope occurred within 8 days of initiation of quinidine therapy in three of the six patients. Sustained ventricular tachycardia was observed during quinidine associated arrhythmia in three of six patients with syncope; nonsustained ventricular tachycardia or complex ventricular ectopic activity while on this therapy was observed before syncope in the other three patients in Group A.(ABSTRACT TRUNCATED AT 250 WORDS)

Common pulmonary vein atresia: the role of extracorporeal membrane oxygenation.

Common pulmonary vein atresia is a rare form of cyanotic congenital heart disease in which the pulmonary veins join to form a blind confluence that does not communicate with the heart or the major systemic veins. Twenty-one cases have been reported since the lesion was first described in 1962; only two patients with this lesion have survived. Over a 4-year period, common pulmonary vein atresia was diagnosed in five newborns referred to the San Diego Regional Extracorporeal Membrane Oxygenation Program. All five improved dramatically as a result of venoarterial bypass. Congenital heart disease was diagnosed at autopsy in the initial case and by cardiac ultrasound and/or catheterization in the others. Surgical repair was attempted in three neonates; all three required continued extracorporeal membrane oxygenation support postoperatively because of pulmonary hypertension and severe pulmonary parenchymal disease. One infant died of respiratory insufficiency at 3 months of age. The other two survived and were discharged from the hospital. The diagnostic and therapeutic dilemmas posed by this lesion and the life-saving potential for extracorporeal membrane oxygenation in this rapidly fatal cardiac anomaly are the bases of this report.

Neurodevelopmental outcomes in children with Fontan repair of functional single ventricle.

OBJECTIVES: The purpose of this study was to assess the neurodevelopmental status of children after Fontan repair of functional single ventricle and to examine the relationship between cognitive function and selected patient characteristics. STUDY DESIGN: Neurodevelopmental tests including the Stanford-Binet Intelligence (IQ) scale and the Developmental Test of Visual Motor Integration (VMI) were administered to 32 children (26 months to 16 years of age) with complex single ventricle. The mean and distribution of IQ and VMI scores were compared with population norms. The relationship between test scores and patient characteristics was examined utilizing analysis of variance and correlational methods. RESULTS: The majority of children had intellectual function within the normal range (mean, 97.5 +/- 12.1). Below average VMI scores were found in 21.4% of children. There were no significant correlations between intellectual function or visual motor integration ability and preoperative oxygen saturation or age at Fontan. Children who had deep hypothermic circulatory arrest during a prior Norwood procedure tended to have a lower IQ score. CONCLUSIONS: Intellectual development in children with Fontan repair of complex heart defects is essentially within the normal range. Visual motor integration deficits may be more prevalent in these children. In our population, the duration and degree of preoperative hypoxemia had no apparent effect on cognitive function.

Atrial overdrive pacing for conversion of atrial flutter in children.

Twenty-three successive patients with 27 different episodes of sustained atrial flutter were treated with atrial pacing for conversion of the tachyarrhythmia; 15 patients with 16 episodes of atrial flutter underwent intracardiac right atrial pacing and eight patients with 11 episodes of atrial flutter were treated with transesophageal atrial pacing. Ten of sixteen episodes (63%) and eight of 11 episodes (73%) were successfully converted using intracardiac and transesophageal techniques, respectively. Mean flutter cycle length for all 27 episodes was 219 ms (mean heart rate 274 beats per minute); successful pacing conversion cycle length (n = 15) was 72% of the flutter cycle length. Hemodynamic, electrophysiologic, and roentgenographic data were not predictive of conversion by either technique. Induction of localized atrial fibrillation or failure to meet critical pacing criteria may explain pacing failures. Based on this experience, a trial of transesophageal atrial pacing for acute conversion of any episode of atrial flutter in children prior to direct current cardioversion is recommended.

Chronic verapamil therapy in pediatric and young adult patients with hypertrophic cardiomyopathy.

Oral verapamil, 5.2 +/- 1.1 mg/kg/day (range 2.8 to 7), was administered to 13 pediatric patients with hypertrophic cardiomyopathy for 13 +/- 6 months (range 2 to 20). The patients had significant symptomatic improvement on verapamil therapy. Murmur intensity diminished in 6 patients during therapy and left ventricular (LV) electromotive forces on the electrocardiogram diminished in 4, increased in 5 and did not change in 4. Exercise endurance increased from 8.4 +/- 3.9 to 10.9 +/- 2.8 minutes (p less than 0.01). Seven patients had ST-segment depression (0.38 +/- 0.28 mV) before verapamil therapy, which improved after verapamil therapy in 5 (0.24 +/- 0.17 mV, p less than 0.02). Of 4 patients with exercise-induced ventricular ectopic activity, 3 had diminution or abolishment of ectopy following verapamil. By echocardiography, the patients had an increase in LV end-diastolic dimension from 3.4 +/- 0.7 to 3.9 +/- 0.8 cm (p less than 0.01), with no significant change in shortening fraction (46.1 +/- 8.0% vs 44.6 +/- 8.0%). When adjusted for body size and age there was a significant decrease in LV septal thickness (from 106 +/- 70 to 45 +/- 52% of predicted normal values, p less than 0.05) and LV posterior wall thickness (from 40 +/- 45 to 5 +/- 26% of predicted normal values p = 0.05) after verapamil. Isovolumic relaxation time decreased from 69 +/- 26 to 42 +/- 19 ms after verapamil (p less than 0.01). Systolic anterior motion of the anterior mitral leaflet disappeared in 5 of 8 patients and midsystolic closure of the aortic valve was no longer present in 4 of 8.(ABSTRACT TRUNCATED AT 250 WORDS)

Measurement of left ventricular ejection fraction in pediatric patients using the nuclear stethoscope.

Left ventricular (LV) ejection fraction (EF) was measured in 25 patients, aged 2 weeks to 20 years (mean 8.6 years), using a portable nonimaging scintillation stethoscope. Technically satisfactory studies were obtained in 23 patients. LVEF was validated by cineangiography in 19 patients and by standard gated blood pool scintigraphy in 4. EF measured by the nuclear stethoscope correlated well with values obtained by cineangiography or scintigraphy (r = 0.869, p less than 0.001) over a wide range of EF values (18 to 79%). In children younger than 5 years (n = 11), the correlation (r = 0.728, p less than 0.02) was less satisfactory than in those older than 5 years (r = 0.926; p less than 0.001). Although modifications in the instrument and further clinical trials with the stethoscope are needed before the device becomes clinically useful to pediatric cardiologists, our data indicate that the nuclear stethoscope can provide reliable assessment of LVEF in pediatric patients.