Patterns of Electrocardiographic Abnormalities in Children with Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy (HCM), a common cardiomyopathy in children, is an important cause of morbidity and mortality. Early recognition and appropriate management are important. An electrocardiogram (ECG) is often used as a screening tool in children to detect heart disease.

Impact of Obesity on Left Ventricular Thickness in Children with Hypertrophic Cardiomyopathy.

Obesity is associated with additional left ventricular hypertrophy (LVH) in adults with hypertrophic cardiomyopathy (HCM). It is not known whether obesity can lead to further LVH in children with HCM. Echocardiographic LV dimensions were determined in 504 children with HCM.

Risk factors for lethal arrhythmic events in children and adolescents with hypertrophic cardiomyopathy and an implantable defibrillator: An international multicenter study.

Background: Predictors of risk of lethal arrhythmic events (LAE) is poorly understood and may differ from adults in children with hypertrophic cardiomyopathy (HCM).

Objective: The purpose of this study was to determine predictors of LAE in children with HCM.

Methods: A retrospective data collection was performed on 446 children and teenagers 20 years and younger (290 [65%] male; mean age 10.

Electrocardiograms in Healthy North American Children in the Digital Age.

Background: Interpretation of pediatric ECGs is limited by lack of accurate sex- and race-specific normal reference values obtained with modern technology for all ages. We sought to obtain contemporary digital ECG measurements in healthy children from North America, to evaluate the effects of sex and race, and to compare our results to commonly used published datasets.

Methods: Digital ECGs (12-lead) were retrospectively collected for children ≤18 years old with normal echocardiograms at 19 centers in the Pediatric Heart Network.

Anomalous left pulmonary artery origin from internal carotid artery: prospective echocardiographic diagnosis of a previously unknown variant.

We present a neonate with dextrocardia, tetralogy of Fallot, right arch, and aberrant left subclavian artery with left pulmonary artery origin from the left internal carotid artery, which is previously unreported.

Temporary atrial pacing for cardiac output after pediatric cardiac surgery.

Pediatric cardiothoracic surgery is often associated with low cardiac output in the postoperative period. This study sought to determine whether increasing heart rate via temporary atrial pacing is beneficial in augmenting cardiac output. Patients younger than 18 years who underwent cardiothoracic surgery and had no perioperative arrhythmias were eligible for the study.

Lessons learned from preparticipation cardiovascular screening in a state funded program.

In 2007, the Texas legislature appropriated money for a pilot study to evaluate cardiovascular screening of student athletes to identify those who might be at risk of sudden death using a questionnaire, physical examination, electrocardiography, and limited echocardiography. We sought to determine (1) the feasibility of a state-wide cardiovascular screening program, (2) the ability to reliably identify at-risk subjects, and (3) problems in implementing screening state wide. The data were analyzed using established pediatric electrocardiographic and echocardiographic criteria.

Relation of right ventricular pacing site to left ventricular mechanical synchrony.

Transvenous pacing leads are regularly placed in the right ventricular (RV) apex. Pediatric patients can develop myopathic changes after long-term RV apical pacing. Left ventricular (LV) mechanical dyssynchrony, estimated with echocardiography, may explain the acute decrease in LV function and long-term histopathologic changes.

Managed ventricular pacing in pediatric patients and patients with congenital heart disease.

Ventricular dyssynchrony induced by ventricular pacing (VP) may predispose patients to congestive heart failure. The detrimental effects of VP are directly related to the cumulative percentage of VP (Cum%VP). Managed VP (MVP) is a novel pacing algorithm developed to minimize unnecessary VP by uncoupling atrial pacing from VP.

Genetic factors are important determinants of neurodevelopmental outcome after repair of tetralogy of Fallot.

Objective: Adverse neurodevelopmental sequelae are common in children with congenital heart defects. Tetralogy of Fallot is part of the clinical phenotype of many genetic syndromes. We evaluated the determinants of neurodevelopmental outcome in patients with tetralogy of Fallot.

Substrate characterization of ventricular tachycardia in a porcine model of tetralogy of Fallot using noncontact mapping.

Background: Ventricular tachycardia (VT) in patients following tetralogy of Fallot (TOF) repair is challenging to map because of the presence of scar, patch material, and hemodynamic residua of surgery. This study investigates whether noncontact mapping can identify the arrhythmia substrate in a porcine model that involves a right ventricular outflow tract (RVOT) patch and either chronic volume or pressure load on the right ventricle.

Methods: Nine infant pigs (3-5 kg) underwent surgery involving an RVOT patch and creation of pulmonary insufficiency (PI, n = 4) or pulmonary stenosis (PS, n = 5).

The roles of chronic pressure and volume overload states in induction of arrhythmias: an animal model of physiologic sequelae after repair of tetralogy of Fallot.

Objective: Sudden death occurs in as many as 8% of patients after repair of tetralogy of Fallot and has been attributed to arrhythmias. The purpose of this study was to establish an animal model to evaluate the individual contribution of different physiologic sequelae after tetralogy of Fallot repair in the development of late-onset arrhythmias.

Methods: Forty-nine piglets were divided into 5 groups: (1) pulmonary artery band; (2) pulmonary valvotomy; (3) pulmonary artery band plus pulmonary valvotomy; (4) infundibular scar; and (5) age-matched control animals.

Impact of re-coarctation following the Norwood operation on survival in the balloon angioplasty era.

Objectives: The objective of this study was to determine the efficacy of balloon angioplasty (BA) by comparing the immediate and long-term outcomes of patients with and without re-coarctation after a Norwood procedure.

Background: Although BA has become the standard means for treating recurrent coarctation following a Norwood operation, it has been suggested that re-coarctation remains a significant cause of morbidity and mortality.

Methods: Patients who survived a Norwood operation from December 1986 through June 2001 were studied.

Postpericardiotomy syndrome after permanent pacemaker implantation in children and young adults.

Background: Postpericardiotomy syndrome (PPS) occurs in 10% to 50% of pediatric patients after cardiac surgery. The incidence and outcome of PPS after permanent pacemaker implantation in children is not described.

Methods: A retrospective analysis was performed of all pediatric patients who underwent isolated placement of a pacemaker between January 1984 and December 2002.

Midaortic syndrome in the fetus and premature newborn: a new etiology of nonimmune hydrops fetalis and reversible fetal cardiomyopathy.

Nonimmune hydrops fetalis is the final common pathway of many conditions that ultimately result in fetal anasarca. Even after extensive evaluation, the etiology of a small percentage of cases of hydrops remains unknown. We present a case of midaortic syndrome, also known as abdominal coarctation syndrome, in a fetus with hydrops and a severe cardiomyopathy.