Track topics on Twitter Track topics that are important to you
Hypothesis 1 (H1): Epicardial biventricular pacing is a safe and feasible method of pacing in young patients.
Over the last two years, physicians at Children’s Healthcare of Atlanta have been implanting epicardial BiV pacing systems in children determined to have ventricular dyssynchrony caused by numerous cardiac diagnoses. The decision to use these pacing systems was based on the knowledge gained by adult studies. Since the use of these pacing systems in the pediatric population has not been formally studied, we propose a study to retrospectively review the safety and feasibility of epicardial BiV pacing in pediatric patients. This study will involve the review of the medical records of children who received epicardial BiV systems at Children’s Healthcare of Atlanta between January 2002 and May 2004.
Synchronous activation of the right and left ventricles requires a normally functioning sinoatrial (SA) node, atrioventricular (AV) node and ventricular conduction system. When AV conduction has been interrupted by congenital heart block or acquired damage to the AV node, impulses arising from the SA node do not reach the ventricular myocardium. Standard therapy involves the placement of a permanent pacing system. In young children, such a system consists of either placing a single epicardial pacing lead on the right ventricular (RV) surface or separate epicardial pacing leads placed on the right atrium (RA) and RV. The former is commonly referred to as single chamber pacing and the latter as dual chamber pacing [AV sequential, single-site (SS) ventricular pacing]. The decision regarding single versus dual chamber lead placement is heavily influenced by operator convenience in the setting of a limited sternotomy. The main functions of the pacing system are sensing spontaneous activity and delivering pacing stimuli when appropriate. The two major advantages of dual chamber pacing are maintenance of physiologic heart rates and restoration of AV synchrony. The disadvantage of this system, however, is that the intrinsic synchronous depolarization of the ventricles is interrupted by initial paced ventricular activation in the RV rather than via the specialized His-Purkinje system; thus desynchronizing ventricular electrical activation. In addition, recent studies have demonstrated that despite early institution of cardiac pacing, some infants and children with AV block (AVB) develop late-onset left ventricular (LV) dilated cardiomyopathy over a follow-up period of 10 years.(1) The underlying mechanisms for this cardiomyopathy are not clear. A novel method of pacing (biventricular pacing, BiV) has been used in adult patients with left bundle branch block (LBBB, which results in dysynchronous ventricular activation) and congestive heart failure (CHF). Biventricular pacing in adults involves transvenous endocardial pacing leads placed in the RA, RV apex and LV via the coronary sinus. This results in “resynchronization” of ventricular activation, presumably by restoring a “normal” ventricular activation sequence, and has been associated with decreased CHF symptoms and improved ventricular function.
Children with acquired or congenital AVB, on the other hand, typically have a narrow QRS; owing to a midline ventricular escape rhythm and synchronous ventricular activation. The typical modes of pacing (VVI or DDD, single-site ventricular) in these children result in interventricular dyssynchrony, as described above. Recent studies in adult populations (DAVID, AAIR vs. DDDR in SSS, and MOde Selection trials)(2-4) demonstrated the detrimental effects of standard single-site ventricular pacing. Unfortunately, children with acquired and/or congenital AVB do not have the option of pacing or no pacing, and are destined to potentially decades of being 100% ventricular paced. This further emphasizes the importance of optimizing pacing strategies in this young, vulnerable population.
Specific Aim 1 (SA1): To evaluate the safety and feasibility of biventricular epicardial pacing in children.
Observational Model: Defined Population, Observational Model: Natural History, Time Perspective: Longitudinal, Time Perspective: Retrospective
Children's Healthcare of Atlanta
Children's Healthcare of Atlanta
Published on BioPortfolio: 2014-08-27T03:47:05-0400
The goal of this study is to better characterize the metabolic alterations and sugar structure alterations (glycosylation abnormalities) in patients diagnosed with Congenital Disorders of ...
Children with congenital heart disease are at risk for neurodevelopmental disorders that will impact their quality of life and their integration into society. The aim of this study is to ...
This study aims to identify whether an all breast milk (BM) diet would improve outcomes in neonates with congenital gastrointestinal disorders (CGD) by facilitating an earlier transition o...
The objective of the study is to investigate congenital disorders of glycosylation in congenital heart diseases without a clear molecular or genetic basis.
CMV lesions were found in the olfactory system of children with congenital CMV infection but no study has hitherto examined the impact of congenital CMV infection on olfaction. So the inve...
Congenital cranial dysinnervation disorders are developmental abnormalities of cranial nerves that often include abnormal synkinesis. Among the most common ophthalmic congenital cranial dysinnervation...
In 20% of neurodevelopmental disorders (NDD) and congenital abnormalities (CA) the cause would be a genomic imbalance detectable only by chromosomal microarrays (CMA).
Congenital dyserythropoietic anemias are rare blood disorders characterized by congenital anemia and a wide range of morphological and functional abnormalities of erythroid precursors.
Congenital disorders of glycosylation (CDG) are a group of more than 130 inborn errors of metabolism affecting N-linked, O-linked protein and lipid-linked glycosylation. The phenotype in CDG patients ...
A heterogeneous group of disorders characterized by a congenital defect in neuromuscular transmission at the NEUROMUSCULAR JUNCTION. This includes presynaptic, synaptic, and postsynaptic disorders (that are not of autoimmune origin). The majority of these diseases are caused by mutations of various subunits of the nicotinic acetylcholine receptor (RECEPTORS, NICOTINIC) on the postsynaptic surface of the junction. (From Arch Neurol 1999 Feb;56(2):163-7)
Congenital disorders, usually autosomal recessive, characterized by severe generalized lack of ADIPOSE TISSUE, extreme INSULIN RESISTANCE, and HYPERTRIGLYCERIDEMIA.
A genetically heterogeneous group of heritable disorders resulting from defects in protein N-glycosylation.
Rare congenital metabolism disorders of the urea cycle. The disorders are due to mutations that result in complete (neonatal onset) or partial (childhood or adult onset) inactivity of an enzyme, involved in the urea cycle. Neonatal onset results in clinical features that include irritability, vomiting, lethargy, seizures, NEONATAL HYPOTONIA; RESPIRATORY ALKALOSIS; HYPERAMMONEMIA; coma, and death. Survivors of the neonatal onset and childhood/adult onset disorders share common risks for ENCEPHALOPATHIES, METABOLIC, INBORN; and RESPIRATORY ALKALOSIS due to HYPERAMMONEMIA.
A syndrome of congenital facial paralysis, frequently associated with abducens palsy and other congenital abnormalities including lingual palsy, clubfeet, brachial disorders, cognitive deficits, and pectoral muscle defects. Pathologic findings are variable and include brain stem nuclear aplasia, facial nerve aplasia, and facial muscle aplasia, consistent with a multifactorial etiology. (Adams et al., Principles of Neurology, 6th ed, p1020)
Pediatrics is the general medicine of childhood. Because of the developmental processes (psychological and physical) of childhood, the involvement of parents, and the social management of conditions at home and at school, pediatrics is a specialty. With ...
Health care (or healthcare) is the diagnosis, treatment, and prevention of disease, illness, injury, and other physical and mental impairments in humans. Health care is delivered by practitioners in medicine, chiropractic, dentistry, nursing, pharmacy, a...
Cardiovascular disease (CVD)
Acute Coronary Syndromes (ACS) Blood Cardiovascular Dialysis Hypertension Stent Stroke Vascular Cardiovascular disease (CVD) includes all the diseases of the heart and circulation including coronary heart disease (angina...