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The mucopolysaccharidoses (MPSs) are inherited lysosomal storage disorders caused by the absence of functional enzymes that contribute to the degradation of glycosaminoglycans (GAGs). The progressive systemic deposition of GAGs results in multi-organ system dysfunction that varies with the particular GAG deposited and the specific enzyme mutation(s) present. Cardiac involvement has been reported in all MPS syndromes and is a common and early feature, particularly for those with MPS I, II, and VI. Cardiac valve thickening, dysfunction (more severe for left-sided than for right-sided valves), and hypertrophy are commonly present; conduction abnormalities, coronary artery and other vascular involvement may also occur. Cardiac disease emerges silently and contributes significantly to early mortality. The clinical examination of individuals with MPS is often difficult due to physical and, sometimes, intellectual patient limitations. The absence of precordial murmurs does not exclude the presence of cardiac disease. Echocardiography and electrocardiography are key diagnostic techniques for evaluation of valves, ventricular dimensions and function, which are recommended on a regular basis. The optimal technique for evaluation of coronary artery involvement remains unsettled. Standard medical and surgical techniques can be modified for MPS patients, and systemic therapies such as hematopoietic stem cell transplantation and enzyme replacement therapy (ERT) may alter overall disease progression with regression of ventricular hypertrophy and maintenance of ventricular function. Cardiac valve disease is usually unresponsive or, at best, stabilized, although ERT within the first few months of life may prevent valve involvement, a fact that emphasizes the importance of early diagnosis and treatment in MPS.

BACKGROUND: As part of an effort to validate the General Practice Research Database (GPRD) for future studies of medication use in pregnancy, this study examined whether the rates of all, and specific types of, congenital heart defects obtained from the GPRD are similar to those obtained from UK national systems. METHODS: The prevalence rates of heart defects for 2001–2003 were determined from the GPRD and compared with both the National Congenital Anomaly System (NCAS) and the European Concerted Action of Congenital Anomalies and Twins (EUROCAT). Rate ratios (RRs) and 95% CIs were calculated comparing the prevalence of all congenital heart defects as well as specific types of heart defects in the three data sources. In addition, the effect of the child's age on the frequency of heart defects in the GPRD was determined. RESULTS: The prevalence of heart defects in the GPRD was more than twice as high as in the NCAS and slightly higher than in the EUROCAT. All differences were statistically significant. The prevalence of specific heart defects varied across the GPRD, NCAS, and EUROCAT. The measured prevalence of congenital heart defects in the GPRD was higher if calculated including children up to age 6. CONCLUSIONS: The comparisons of the GPRD prevalence rates to national prevalence estimates demonstrate that the GPRD can serve as a more complete source of background prevalence for the most commonly occurring congenital heart defects, which is essential to properly assess possible associations between maternal exposures and congenital heart defects. Birth Defects Research (Part A) 2007. © 2007 Wiley-Liss, Inc.

Objective The purpose of this research was (1) to validate that ventricular septal defect (VSD), tetralogy of Fallot (TOF), and coarctation of the aorta (COA) can be studied in the UK General practice research database (GPRD) and (2) to understand which of the available GPRD components (computerized medical records, questionnaires, and maternal/infant free text) provide maximal information about these heart defects. Methods Using a practitioner questionnaire, the positive predictive value (PPV) of the computerized medical record for VSD, TOF, and COA were determined. Both infant and maternal free text was examined. Concordance between the infant free text information and questionnaires was calculated. The proportion of infant information captured in the maternal free text was determined. Results A 93% response rate was achieved. Based on questionnaire responses, an overall PPV of 93.5% was achieved (VSD = 95%, TOF = 90%, COA = 100%). Approximately half of the records contained infant free text information including information on the type and size of VSD, echocardiogram findings, and surgery. Concordance between the infant's free text and questionnaire information occurred in most of the cases (92–100%). The proportion of infant information in the maternal free text was low (4–19%). Conclusion The GPRD computerized medical records are sufficient to assess VSD, TOF, and COA. This study confirms that maternal free text provides a low yield of limited information pertaining to the infants' defect, while the infant free text may provide an additional information usually obtainable from practitioner questionnaires. The information provided by an infant free text may limit the need for practitioner questionnaire validation. Copyright © 2007 John Wiley & Sons, Ltd.

Background: Dietary copper overload in the rat is associated with morphological abnormalities and lipid peroxidation of hepatic mitochondria. This study was designed to determine if copper hepatotoxicity was associated with functional alterations in mitochondrial respiration in conjunction with lipid peroxidation. Methods: Weanling male rats were pair-fed for 8 weeks on diets containing normal or high levels of copper in combination with sufficient vitamin E. Serum and liver samples were obtained, and hepatic mitochondria were isolated by differential centrifugation. Results: Oxidant injury (decreased levels of hepatic glutathione and alpha tocopherol and increased levels of mitochondrial thiobarbituric acid-reacting substances) was present in the copper-overloaded rats. Serum aminotransferase levels correlated with concentrations of mitochondrial copper and thiobarbituric acid-reacting substances. Copper overload caused a decrease in state 3 respiration and the respiratory control ratio in hepatic mitochondria when several electron donors were used. Analysis of the oxidoreductase activities of the four mitochondrial electron transport protein complexes showed that complex IV (cytochrome C oxidase) activity was reduced by 60% in copper overload. Conclusions: Functional abnormalities of mitochondria accompany lipid peroxidation and the morphological alterations caused by copper overload, supporting the hypothesis that the mitochondrion is one of the major intracellular targets in copper hepatotoxicity.

To assess the prevalence of cardiovascular signs and symptoms in a large group of patients with Hunter syndrome, an X-linked metabolic disorder caused by a deficiency of the lysosomal enzyme iduronate-2-sulfatase.The Hunter Outcome Survey was established to characterize the natural history of Hunter syndrome and to assess the response to enzyme replacement therapy. Echocardiographic and electrocardiographic examination results were available for 102 patients who were enzyme replacement therapy-naïve in the Hunter Outcome Survey (median age at examination, approximately 8 years) as of Jan 23, 2009.The most common cardiovascular finding was valve disease, which was present in 63% of patients. Left ventricular hypertrophy (defined as left ventricular mass indexed to height(2.7) ≥50 g/m(2.7)) was found in 48% of patients18 years old. Elevated blood pressure (defined as a Z score ≥2 for systolic blood pressure or diastolic blood pressure) was present in 25% of patients18 years old. Other findings included abnormal heart frequency (7%), arrhythmia (5%), and congestive heart failure (6%).Treating physicians should be aware of the early emergence of cardiovascular manifestations in patients with Hunter syndrome so that appropriate treatment can be initiated.

Little data are available on the hemodynamic effects of premedications and anesthetic agents on infants and children. Ketamine is the most frequently used anesthetic agent for cardiac catheterization procedures in pediatric patients with congenital heart disease. Previous reports both suggest and deny ketamine's pulmonary vasoreactive effects. Since the advent of sophisticated noninvasive equipment, one of the few indications for cardiac catheterization is to obtain accurate pressure data. If ketamine alters pulmonary vascular resistance, it would negate the primary reason for the procedure. Because the patient population studied herein resides greater than or equal to 1,200 meters above sea level, concerns about pharmacologic effects on pulmonary vascular resistance are enhanced. Simultaneous pulmonary artery and aortic pressures, thermodilution cardiac outputs, and blood gases were measured in room air (16% oxygen) and with ketamine infusion in 14 patients at cardiac catheterization. Reaction to hypoxia identified 3 groups: normal, intermediate and hyperresponders. The normal responders had normal resistance ratios (0.11) in room air and had little resistance ratio response to hypoxia (+0.02), hyperoxia (-0.03) or ketamine (+0.01). The intermediate responders had a slightly higher but normal resistance ratio (0.20) in room air, and a moderate reaction to hypoxia (+0.13), hyperoxia (-0.08) and ketamine (+0.11). The hyperresponders had an elevated resistance ratio (0.42) in room air and a striking reaction to hypoxia (+0.65), hyperoxia (-0.17) and ketamine (+0.49). Hypoxia and ketamine have a greater effect on resistance ratio than hypoxia alone in patients with reactive pulmonary vascular beds. Ketamine should not be used in children undergoing procedures to establish operability based on pulmonary vascular resistance or pulmonary vascular reactivity.

Patient's with severe Ebstein's anomaly of the tricuspid valve presenting in the newborn period often have profound cyanosis and are at increased risk for sudden death. 1,2 Several strategies have been used to manage these complicated patients. A recent surgical technique described by Starnes et al 3 involved oversewing the tricuspid valve and creating a Blalock-Taussig shunt; this palliation leads to eventual Fontan repair. Further options include Blalock-Taussig shunt alone, cardiac transplantation, extracorporeal membrane oxygenation and tricuspid valve repair or replacement. 1,4,5 In this article, we report 3 consecutive newborns with severe Ebstein's anomaly and cyanosis who were treated with prolonged prostaglandin E 1 infusions. These cases suggest that prostaglandin E 1 may obviate the need for early surgical intervention in critically ill neonates with Ebstein's anomaly and allow survival until surgical management can be pursued at lower risk.

We have studied the intrinsic fluorescence of the 12 tryptophan residues of electron-transfer flavoprotein:ubiquinone oxidoreductase (ETF:QO). The fluorescence emission spectrum (lambda ex 295 nm) showed that the fluorescence is due to the tryptophan residues and that the contribution of the 22 tyrosine residues is minor. The emission maximum (lambda m 334 nm) and the bandwidth (delta lambda 1/2 56 nm) suggest that the tryptophans lie in hydrophobic environments in the oxidized protein. Further, these tryptophans are inaccessible to a range of ionic and nonionic collisional quenching agents, indicating that they are buried in the protein. Enzymatic or chemical reduction of ETF:QO results in a 5% increase in fluorescence with no change of lambda m or delta lambda 1/2. This change is reversible upon reoxidation and is likely to reflect a conformational change in the protein. The ubiquinone analogue Q0(CH2)10Br, a pseudosubstrate of ETF:QO (Km = 2.6 microM; kcat = 210 s-1), specifically quenches the fluorescence of one tryptophan residue (Kd = 1.6-3.2 microM) in equilibrium fluorescence titrations. The ubiquinone homologue UQ-2 (Km = 2 microM; kcat = 162 s-1) and the analogue Q0(CH2)10OH (Km = 2 microM; kcat = 132 s-1) do not quench tryptophan fluorescence; thus the brominated analogue acts as a static heavy atom quencher. We also describe a rapid purification for ETF:QO based on extraction of liver submitochondrial particles with Triton X-100 and three chromatographic steps, which results in yields 3 times higher than previously published methods.

We have examined 23 fibroblast lines from patients with neonatal and late onset glutaric acidemia type II and fibroblasts from four parents of these patients. Fifteen of these patients are previously unreported. Results of these investigations show deficiency of electron transfer flavoprotein or electron transfer flavoprotein-ubiquinone oxidoreductase activity in all of the patients' fibroblasts. Immunoblots indicate that the steady state levels of the antigens is very low or undetectable in most of the neonatal onset patients; however, cross-reacting antigen without electron transfer activity is observed in several glutaric acidemia type II fibroblast lines. Assay of parental lines confirm the autosomal transmission of deficiencies of proteins. Of particular interest is the clinical heterogeneity among these patients. Patients may present with an extrapyramidal movement disorder as observed in glutaric aciduria type I, without the typical organic aciduria typical of glutaric acidemia type II even in the presence of severe enzyme deficiency, or with renal cystic dysplasia accompanying electron transfer flavoprotein deficiency. Renal cystic dysplasia had previously been reported only in patients with electron transfer flavoprotein-ubiquinone oxidoreductase deficiency.

Glutaric acidemia, which is due to inherited deficiency of glutaryl-CoA dehydrogenase, is characterized clinically by progressive dystonia and dyskinesia in childhood, and pathologically by degeneration of the caudate and putamen. Results using newer imaging techniques (computer tomography and magnetic resonance image scanning) suggest that neurological involvement in this condition begins before birth, and that gliosis of the basal ganglia is a relatively late event. Glutaric acidemia type II is usually due to inherited deficiency of electron transfer flavoprotein (ETF) or ETF:ubiquinone oxidoreductase, but some patients with typical disease may have another, to date undefined, abnormality. There may also be a clinical phenotype of glutaric acidemia type II which, like glutaryl-CoA dehydrogenase deficiency, is characterized by a movement disorder and by degeneration of the basal ganglia.

A male infant with glutaric aciduria II secondary to electron transfer flavoprotein: ubiquinone oxidoreductase deficiency is compared to previously reported cases of glutaric aciduria II. A common pattern of anomalies in patients with malformations (8/16) includes macrocephaly, large anterior fontanelle, high forehead, flat nasal bridge, telecanthus, and malformed ears. Abnormalities such as hypotonia, cerebral gliosis, heterotopias, hepatomegaly, hepatic periportal necrosis, polycystic kidneys, and genital defects in glutaric aciduria II are reminiscent of those in Zellweger syndrome, whereas elevations of glutaric, ethylmalonic, adipic, and isovaleric acids are quite distinctive. A unique ultrastructural alteration of the glomerular basement membrane was observed in the proposita. This manifestation may represent an early stage in renal cyst formation and provide a diagnostic criterion for glutaric aciduria II when enzyme studies are unavailable.

Forty patients with fragile X [fra(X)] or Martin-Bell syndrome, confirmed by chromosome analysis, underwent full cardiac evaluation including physical examination, chest film, electrocardiography (ECG), and M-mode and 2-dimensional echocardiography. Thirty-four males and six females were studied. Although all patients were asymptomatic, seven males were found to have mild aortic root dilatation. All seven also had evidence of mitral valve prolapse. Twenty-two (55%) of the study patients had mitral valve prolapse with either a click or murmur heard on physical examination and confirmation by M-mode echocardiography. The frequency of mitral valve prolapse was the same in males and females, but 80% of males older than 18 years had mitral valve prolapse. These findings support the hypothesis of a connective tissue dysplasia in the fra(X) syndrome.

GA2 may be due to inherited deficiency of electron transfer flavoprotein (ETF) or ETF-ubiquinone oxidoreductase (ETF-QO), proteins that transfer electrons from soluble mitochondrial flavoprotein dehydrogenases to the main respiratory chain. Cell lines from 11 severely affected GA2 infants were assayed for ETF by acy1 CoA:Q1 activity (using purified general acyl CoA dehydrogenase and ETF-QO as electron donor and acceptor), and for ETF-QO by comproportionation of ETF and by NADH:ETF reductase activity. All but one were deficient in ETF (5 patients; none with anomalies) or ETF-QO (5 patients; all with anomalies). The one that was not was from a girl with nonketotic hypoglycemia, a typical Zellweger facies, normal serum very long chain fatty acids, and glutaric, ethylmalonic, 3-hydroxyisovaleric and isovalerylglycine in urine who died at 6 months of age. Autopsy showed hypertrophic cardiomyopathy, moderate lipid deposition and canalicular stasis in liver, focal glomerular immaturity and cortical cysts in the kidney, and cysts in the cerebral cortex and basal ganglia. Glutaryl CoA dehydrogenase activity in fibroblasts was normal. This GA2 patient may have a defect in electron transfer between ETF-QO and complex III, and her phenotype may indicate interaction between peroxisomal and mitochondrial compartments.

Five patients (4-9 yrs.) presented in five years with primary pulmonary hypertension (PPH). Each was initially evaluated for seizures or syncope. Two sisters (#1s2) were Hispanic and resided at 5,200′. Two brothers (#3&4) were black and resided at 5,200′. An only child (#5) resided at 9,000′. Cardiac catheterization with hyperoxia was performed in all and one received additional prostaglandin 12 (PGI2). Structural heart disease was ruled out in all. Resistance ratios (R.R.) were calculated in room air and 100% O2. Three of the five patients died 9.2 months after diagnosis. Two of the deaths (#1&2) occurred after steady clinical deterioration at 5,200′. The third child (#5) dramatically improved after moving to sea level but died five days after returning to altitude. One of the black males has significantly improved since moving to sea level (#4) and his brother with milder disease has spontaneously improved while remaining at altitude (#3). PPH is a rare and rapidly fatal disease in childhood. In patients presenting at altitude, the clinical course may be altered or reversed by moving to sea level.