Childhood Air Pollutant Exposure and Carotid Artery Intima-Media Thickness in Young Adults Outcomes of Restrictive Cardiomyopathy in Childhood and the Influence of Phenotype: A Report From the Pediatric Cardiomyopathy Registry Editors’ Picks

Summary— The atherogenic process has important determinants early in life. Childhood exposure to ozone may be a novel risk factor for carotid artery intima-media thickness in young adults. Exposure to ambient air pollutants increases risk for cardiovascular health outcomes in adults. Early life exposure to ozone has been associated with childhood lung function development. Systemic inflammation induced first in the lung may be propagated throughout the body to target other organ systems. Regulation of air pollutants and efforts that focus on limiting childhood exposures continue to be important public health goals to potentially reduce atherosclerotic burden and its consequences. Conclusions— Childhood exposure to O3 may be a novel risk factor for carotid artery intima-media thickness in a healthy population of college students. Regulation of air pollutants and efforts that focus on limiting childhood exposures continue to be important public health goals. 1 Summary— The origin of congenital or childhood nonimmune isolated atrioventricular (AV) block remains unknown. Because familial clustering of progressive cardiac conduction defects of unknown causes, including congenital AV block, has been reported, we hypothesized that idiopathic AV block in the young may be a heritable disease. This hypothesis was tested in a nationwide (France) retrospective cohort of 141 idiopathic pediatric AV blocks. Screening ECGs from 130 parents (mean age 42.0±6.8 years, 57 couples) were compared with 130 matched healthy control subjects. Although a family history of sudden death or progressive cardiac conduction defect, respectively, was found in only 1.4% and 11.1% of parents, conduction abnormalities were more frequent in parents than in control subjects, found in 50.8% versus 4.6%, respectively ( P <0.001), and estimated heritability for isolated conduction disturbances was 91% (standard error, 1.019; P =2.10−16). SCN5A mutation screening identified 2 mutations in 2 patients among 97 children. Thus, ECG screening in parents of children affected by idiopathic AV block revealed diffuse subclinical impairment of cardiac conduction, which provides strong evidence for a genetic origin in congenital and childhood nonimmune isolated AV block. Such an ECG screening may be helpful in clinical practice if other obvious causes have been ruled out. Heritability esti-mate confirmed a high contribution of genetic factors, which opens the field to further molecular studies. Conclusions— ECG screening in parents of children affected by idiopathic AV block revealed a high prevalence of conduction abnormalities. These results support the hypothesis of an inheritable trait in congenital and childhood nonimmune isolated AV block. 2 Summary— Restrictive cardiomyopathy is a rare form of cardiomyopathy in childhood with a few risk factors identified for death or transplantation. This analysis from the Pediatric Cardiomyopathy Registry identified 152 cases of restrictive cardiomyopathy among 3375 children with cardiomyopathy (4.5%), approximately one-third of whom had a mixed restrictive/hypertrophic phenotype. Survival did not differ between those with pure and mixed phenotypes, but transplant-free survival was inferior in the pure restrictive cardiomyopathy group. Overall outcomes were worse than for all other forms of cardiomyopathy in the Pediatric Cardiomyopathy Registry. Clinical and echocardiographic risk factors at presentation for worse outcome were identified and should aid the clinician in risk stratification. Conclusions— Transplant-free survival is poor for restrictive cardiomyopathy in childhood. Survival is independent of phenotype; how-ever, the restrictive cardiomyopathy/hypertrophic cardiomyopathy phenotype has significantly better transplant-free survival. 3 at presentation and at listing for heart transplantation in children with dilated cardiomyopathy on outcome, we analyzed data from 2 large pediatric registries: the Pediatric Cardiomyopathy Registry and the Pediatric Heart Transplant Study. In the merged data set, there were 261 children with dilated cardiomyopathy. Among the factors studied were age, duration of illness, sex, race, ventricular geometry, and the clinical or histological diagnosis of myocarditis at presentation. We found that death while waiting was associated with ventilator use and older age at listing. A shorter duration of illness was associated with a more urgent listing status (United Network for Organ Sharing status 1). Death after transplantation was associated black race and lower left ventricular end-diastolic dimension z score at presentation. We also found that death after transplantation was associated with the diagnosis of myocarditis at presentation ( P <0.009). Death while waiting was not associated with the diagnosis of myocarditis, and 97% of children with myocarditis survived to transplantation. Furthermore, the most common cause of death after transplantation in the myocarditis group was acute rejection (17%). This is the first study to show that children with dilated cardiomyopathy and myocarditis have significantly higher posttransplantation mortality compared with children without myocarditis. This finding suggests that preexisting viral infection or inflammation could adversely affect heart allograft survival and has implications for the management of these children before and after heart transplantation in the future. or intensive care units in the United Kingdom and Ireland to investigate the relationship between arterial partial oxygen pressure (Pa O 2 ) after resuscitation from cardiac arrest and mortality. We found exposure to supranormal oxygen tension was common, with 33% of patients having Pa O 2 >150 mm Hg on the first blood gas. We demonstrated a significant association between early postarrest hyperoxia and increased mortality after admission to the pediatric intensive care unit. A stronger association was also seen between the degree of hypoxia and mortality. Our data lend support for intervention studies to assess the safety and efficacy of using the lowest inspired oxygen concentration that maintains arterial oxyhe-moglobin saturation of 94% to 96% in the postresuscitation period. Conclusions— Both severe hypoxia and, to a lesser extent, hyperoxia are associated with an increased risk of death after pediatric intensive care unit admission after cardiac arrest. 5 However, our findings indicate that, even under the conditions that might be expected to favor screening used in our base case, estimates of the cost-effectiveness of screening for these diseases are relatively unfavorable, ranging from $91 000 (adolescent participating in sports) to $204 000 per life-year (child with attention-deficit/hyperactivity disorder). Conclusions— Results based on assumptions favoring sudden cardiac death screening indicated that its cost is high relative to its health benefits. 7 Summary— Hypoplastic left heart syndrome is a common form of functional single-ventricle congenital heart disease and is associated with significant morbidity/mortality. A National Heart, Lung, and Institute Pediatric Heart Network study, the Single Ventricle Reconstruction trial, randomized initial surgical Norwood palliation in 549 infants with hypoplastic left heart syndrome to either a right ventricle–pulmonary artery shunt or a modified Blalock-Taussig shunt to determine the optimal surgical approach. The primary result of the trial found better 1-year transplant-free survival in subjects who received a right ventricle–pulmonary artery shunt compared with those who had a modified Blalock-Taussig shunt. This study compared 2-dimen-sional echocardiographic indices to assess the effect of initial shunt type at 4 stages during the trial (at baseline preoperatively, early after the Norwood procedure, immediately before the second-stage surgical procedure, and at 14 months of age). We found that differences in neoaortic annular size and flow patterns between shunt types when the shunts are in place can likely be explained by the different physiologies created rather than by intrinsic differences in cardiac function. After the shunt was removed at the second-stage surgery, echocardiographic indices were similar between the 2 groups, including measures of right ventricular function, cardiac and vascular dimensions, neoaortic and tricuspid dimensions and valve function, and neoaortic flow patterns. This lack of shunt-related differences in echocardiographic indices of cardiac and vascular function in survivors of the Norwood procedure at 14 months suggests that the best initial surgical pathway for infants with hypoplastic left heart syndrome remains unclear and emphasizes the importance of longitudinal follow-up of this unique cohort. Conclusions— Indices of cardiac size and function after the Norwood procedure are similar for modified Blalock-Taussig shunt and right ventricle-pulmonary artery shunt by 14 months of age. Interstage differences between shunt types can likely be explained by the physiology created when the shunts are in place rather than by intrinsic differences in cardiac function. 8 disease (KD) is now recognized as the leading cause of acquired heart disease in children in the United States and developed world. The underlying cause of KD and the mechanisms leading to vessel inflammation, coronary artery lesions, and aneurysms, which are the hallmarks of KD, remain largely unknown. Standard therapy with intravenous immunoglobulin (IVIG) effec-tively reduces the incidence of coronary arterial lesions, but 10% to 20% of patients with KD fail to respond to IVIG and thus show a high prevalence of coronary lesions. There is no definitive treatment recommendation for patients who fail to respond to an initial course of IVIG treatment. Rescue treatment for IVIG resistance includes additional IVIG dose(s), steroids, anti–tumor necrosis factor monoclonal antibody, and cyclosporine A, but these approaches have