Charles I Berul

..We sought to determine the implications of implantable cardioverter-defibrillator (ICD) placement in children and patients with congenital heart disease (CHD)...

..This paper reviews current in vivo murine electrophysiology study techniques and genetic mouse models pertinent to human arrhythmia disorders...

..This excess lead may rarely prolapse into the pulmonary artery and potentially interfere with valve function. We sought to determine the response to lead repositioning on pulmonary valve insufficiency...

..This article will first review the indications for permanent pacing in children and will then describe the unique challenges associated with such use...

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..These findings suggest circadian variation in arrhythmia vulnerability that may differ from conventional occupational, physical, or emotional stressors. (J Cardiovasc Electrophysiol, Vol. 13, pp...

..Mechanistic studies indicate that CPVT is mediated by diastolic Ca(2+) overload and increased Ca(2+) leak through the RyR2 channel, implying that treatment targeting these defects might be efficacious in CPVT...

..Outcomes with these hybrid configurations are not well understood...

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..A genetic approach that utilizes a binary inducible transgenic system was used to investigate the disease mechanism and to assess preventability and reversibility of disease features in a mouse model of glycogen-storage cardiomyopathy...

..The literature in adults is inconclusive and no studies have investigated the association between pacing leads and TR in children or congenital heart disease patients...

..We sought to determine the functional assessment and clinical outcomes in pediatric and CHD CRT patients followed uniformly at one institution...

..A preliminary study reported interference in 50% of patients whose devices were interrogated near Apple iPods...

..Atrial pacing is indicated for sinus node dysfunction (SND) after Fontan surgery; preferred lead implantation technique is debated. We compare outcomes of transvenous (TV) and epicardial (Epi) atrial lead implants in this population...

..Data on the safety and efficacy of different lead extraction techniques in this specific patient population are limited...

..Several observations support a model in which Msx2 negatively regulates formation of the conduction system and inappropriate Msx2 up-regulation causes the conduction defects associated with Nkx2-5 mutation...

..Furthermore, patient age, body size, and lead characteristics at implant do not clearly predict venous occlusion...

..Effective pacing therapy may require site-specific placement of pacing leads and precise pacemaker programming...

..TTV leads offer a promising alternative to SEE systems in terms of performance for young patients without intracardiac shunting who do not require open-chest surgery for another indication...

..5 also causes conduction abnormalities, although the onset is after the neonatal stage. Bradycardia and AV conduction failure may contribute to the lethal heart failure and early mortality...

..In a large cohort of pediatric patients with and without SHD undergoing invasive electrophysiology study, we examined the prevalence of MultAP and the effect of both MultAP and SHD on ablation outcomes...

..The risk of AP recurrence appears higher after cryoablation, although safety benefits may provide suitable compensation for this deficiency. Methods for creating more effective cryoablation lesions need to be explored...

..Mice overexpressing a dominant-negative alpha2 subunit of AMPK (TGalpha2DN) provide a tool for selectively inhibiting alpha2, but not alpha1, subunit-associated AMPK activity...

..Our findings suggest that expanded utilization of transvenous systems in smaller patients seems justified when anatomy permits...

..The current standard of care for imaging during supraventricular tachycardia (SVT) ablation uses fluoroscopy, which exposes otherwise healthy children to the potential harmful effects of radiation...

..The aim of this study was to describe a large experience with primary cardiac tumors in pediatric patients, characterize associated arrhythmias, and expand knowledge of natural history and treatment options...

..Hypoplasia of the atrioventricular node, His bundle, and Purkinje system can explain in whole or in part specific conduction and electrophysiologic defects present in Nkx2-5 haploinsufficiency...

..We conclude that Tbx5 is required for Cx40-independent patterning of the cardiac conduction system, and suggest that the electrophysiologic defects in Holt-Oram syndrome reflect a developmental abnormality of the conduction system...

..We explored differences in circulating markers of extracellular matrix turnover between young HCM patients with versus without history of serious arrhythmia...

..Episodic 2:1 block occurs in 9% of adults with atrioventricular nodal reentry tachycardia (AVNRT), but developmental differences in conduction physiology among children could influence this phenomenon...

..Ablation of LKB1 leads to a decreased cardiac efficiency despite normal mitochondrial oxidative metabolism...

..Postnatal conduction defects in Nkx2-5 mutation may result at least in part from a defect in the genetic program that governs the recruitment or retention of embryonic cardiac myocytes in the conduction system...

..Aortic dilation has been anecdotally observed in some children with CCHB, but detailed reports are lacking...

..5 overexpression but not due to heart failure phenotype in vivo. These studies indicate that overexpression of Nkx2.5 in terminally differentiated cardiomyocytes dramatically alters cardiac cell structure and function...

..Supra-annular prosthesis implantation can facilitate mitral valve replacement with a larger prosthesis in children with a small annulus, but little is known about its effect on the outcomes of mitral valve replacement in young children...

..The central role of RyR2 dysfunction in CASQ2 deficiency unifies the pathophysiologic mechanism underlying CPVT due to RyR2 or CASQ2 mutations and suggests a therapeutic approach for these inherited cardiac arrhythmias...

..Inability to induce stable VT for precision mapping and certain high-risk VT locations can be significant obstacles to success...

..The incidence of appropriate and inappropriate discharges, indicators of system failure, and clinical implications of implantable cardioverter defibrillator (ICD) therapy in children and young adults with heart disease is poorly defined...

..Clinically indicated DFT testing, as expected, has a high yield of important information on device function in congenital heart disease and pediatric populations...

..Cardiomyopathy, conduction abnormalities, and ventricular arrhythmias are significant complications of this disease. The mdx ( 5cv ) mouse carries a dystrophin mutation and demonstrates a more severe phenotype than the classic mdx mouse...

..Atrial tachycardias in congenital heart disease are amenable to ATP algorithms in the AT500 pacemaker...

..We sought to determine the diagnostic utility of the Reveal ILR (Medtronic, Inc., Minneapolis, MN, USA) in pediatric patients...

..Clinical experience suggested that ectopic atrial rhythm (EAR) is more frequently observed on preablation ECGs of pediatric patients with AVNRT. This study aimed to determine whether EAR is predictive of AVNRT...

..We propose that consideration of the two alternative hypotheses, in addition to the traditional ICC-centric model, should lead to a richer understanding of cardiac conduction defects and arrhythmogenesis...

..The incidence and potential significance of sustained TWA in pediatric and congenital heart disease (CHD) populations has not been well defined...

..This study aimed to determine the incidence of death and VT in TOF after PVR and to test the hypothesis that PVR leads to improvement in these outcomes...

..We found that inactivation of AMPK did not result in abnormal ATP and glycogen consumption during exercise, cardiac function assessed by heart rhythm telemetry and stress echocardiography, or in maximal exercise capacity...

..This study was undertaken to determine implications of ICD manufacturers' advisories and recalls on children and CHD patients...

..Six5 loss may partly contribute to conduction abnormalities in myotonic dystrophy, particularly infraHisian conduction delay, one of the initial phenotypes of adult-onset cardiac conduction abnormalities in DM patients...

..We suggest that a shared pathway triggered by sarcomere gene mutations links cardiac hypertrophy and arrhythmias in HCM...

..Future research will determine the etiology of the remaining cases, further risk-stratify the known genetic defects, improve current treatment options for these syndromes, and uncover novel therapies...

..The risks of AV block and accessory pathway recurrence are most relevant to anteroseptal and midseptal pathways. These data may be factored into patient selection and the decision whether to ablate...

..Both adult and pediatric algorithms are particularly misleading in non-Ebstein's CHD patients and should be interpreted with caution...

..We describe the first prospective evaluation of defibrillation threshold (DFT) and postshock rhythm in this population...

..Recent discoveries of genetic etiologies have shed new light on the mechanisms underlying arrhythmogenesis and molecular genetics of cardiac electrophysiology...

..These factors should be carefully considered when analyzing PES and burst pacing data in murine models to minimize false positives and optimize accuracy...

..Retrospective studies suggest these rates might be increased by the use of irrigated radiofrequency (RF) ablation...

..The evolution of pediatric electrophysiology from a diagnostic specialty into a therapeutic and interventional subspecialty has advanced the treatment options for children with cardiac arrhythmias and conduction disorders...

..The degree of wall thickening observed in the Fontan atria was not so excessive as to preclude transmural lesions during catheter or surgical ablation of reentrant arrhythmias...

..Epicardial patches require a thoracotomy, and may lead to a restrictive pericardial process. Because of these issues, we have explored novel ICD configurations...

..We hypothesised that endocardial fibroelastosis removal may significantly affect ventricular conduction and myocardial electrical characteristics...

..We analyzed post-transplant outcomes in infants who received a heart from a donor where SIDS was the primary cause of brain death...

..These conduction abnormalities may contribute to the lethal heart failure and early mortality evident in DNA nonbinding mutant Nkx2.5 mice...

..The goal of this study was to identify factors associated with radiofrequency catheter ablation (RFCA) outcomes of intra-atrial re-entrant tachycardia (IART)...

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..It may be advisable to avoid dual-coil leads in patients with the potential for future growth...

..Their quality of life was more strongly correlated with their feelings of anxiety and depression as well as their family functioning than to the severity of their cardiac illness...

..Our data demonstrate in vivo that Gbetagamma plays a crucial role for parasympathetic heart rate control, sinus node automaticity, and atrial arrhythmia vulnerability...

..Delineate prenatal features of Costello syndrome (caused by HRAS mutations), which consists of mental retardation, facial, cardiovascular, skin, and musculoskeletal anomalies, and tumor predisposition...

..Understanding of the molecular and ionic mechanisms underlying cardiac conduction is essential for the appreciation of the pathogenesis of conduction abnormalities in structurally normal and altered hearts...

..These therapies and the available supporting data relevant to pediatrics will be the focus of this review...

..This includes procainamide-sensitive, adenosine-resistant accessory pathways induced in postnatal life that may rarely disappear later in life...

..Spontaneous downregulation of the ACE2 transgene in surviving older animals correlated with restoration of nearly normal conduction, rhythm, and connexin expression...

..Nonautomatic focal atrial tachycardia (NAFAT) has been characterized in adults with structurally normal hearts. This article characterizes NAFAT in a population of patients with complex congenital heart disease...

..This review will address issues of rhythm management and resynchronization therapy in pediatric and congenital heart disease patients with heart failure...

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..Prospective electrophysiologic evaluations may be warranted to establish guidelines for long term pacemaker dependency and criteria for pacing...

..Short-term results showed a low incidence of intra-atrial reentrant tachycardia in all patients. Longer follow-up is necessary to assess clinical efficacy...

..Association with cardiac rejection, clinical course, and mortality varied depending on the tachyarrhythmia mechanism...

..There is a high incidence of appropriate ICD therapy for malignant ventricular arrhythmias in this highly selected group of patients...