A Prospective Management Strategy for Heterotaxy Syndrome with Intestinal Rotation Abnormalities: Imaging Does Not Predict Need for Surgery.

Purpose: Heterotaxy syndrome (HS) affects right-left anatomical development in 3% of children with congenital heart disease. Commonly, these patients have intestinal rotation abnormalities (IRA) that differ from typical malrotation. In this prospective study, we examine the development of a management pathway, imaging findings, and clinical course of patients with HS and IRA.

Ablation of intra-atrial reentrant tachycardias in adults with congenital heart disease: islands, isthmuses, channels, and walls.

Purpose Of Review: The adult congenital heart patient population is rapidly growing due to increasing survival rates, and they often face chronic physiologic challenges as sequalae of both their defects and repairs. Among the most common sequalae are arrhythmias. Here we describe intra-atrial reentrant tachycardia (IART), one of the most commonly seen arrhythmias in the adult congenital heart population, and the approaches to successful ablation in adult congenital heart patients.

Atrial Fibrillation in Patients with Congenital Heart Disease.

Advances in surgical techniques have led to the survival of most patients with congenital heart disease (CHD) up to their adulthood. During their lifetime, many of them develop atrial tachyarrhythmias due to atrial dilatation and scarring from surgical procedures. More complex defects and palliative repairs are linked to a higher incidence and earlier occurrence of arrhythmias.

Management of pediatric tachyarrhythmias on mechanical support.

Background: Pediatric patients with persistent arrhythmias may require mechanical cardiopulmonary support. We sought to classify the population, spectrum, and success of current treatment strategies.

Methods And Results: A multicenter retrospective chart review was undertaken at 11 sites.

Unusually high association of hypertrophic cardiomyopathy and complex heart defects in children with fasciculoventricular pathways.

Introduction: Fasciculoventricular pathways (FVPs) are rare causes of preexcitation that do not mediate tachycardias. We report a two-center experience of pediatric patients with FVP and an unexpectedly high association of complex congenital heart defects (CHDs), chromosomal anomalies, and hypertrophic cardiomyopathy.

Methods: A retrospective review of the electrophysiology database at two institutions was performed to identify patients with FVP from January 2000 to January 2011.

Electrophysiologic substrate and intraventricular left ventricular dyssynchrony in nonischemic heart failure patients undergoing cardiac resynchronization therapy.

Background: Electrocardiographic imaging (ECGI) is a method for noninvasive epicardial electrophysiologic mapping. ECGI previously has been used to characterize the electrophysiologic substrate and electrical synchrony in a very heterogeneous group of patients with varying degrees of coronary disease and ischemic cardiomyopathy.

Objective: The purpose of this study was to characterize the left ventricular electrophysiologic substrate and electrical dyssynchrony using ECGI in a homogeneous group of nonischemic cardiomyopathy patients who were previously implanted with a cardiac resynchronization therapy (CRT) device.

Use of a wearable automated defibrillator in children compared to young adults.

Background: A wearable automated external defibrillator has been shown to be efficacious in the prevention of sudden death in adults who had a history of cardiac arrest but who did not have a permanent internal cardioverter/defibrillator (ICD) placed. The use of a wearable defibrillator has not been established in the pediatric population.

Methods: We retrospectively reviewed the clinical database for the wearable external defibrillator from ZOLL Lifecor Corporation (Pittsburgh, PA, USA).

Cryoablation with an 8-mm tip catheter for pediatric atrioventricular nodal reentrant tachycardia is safe and efficacious with a low incidence of recurrence.

Background: Cryoablation with 4- and 6-mm tip ablation catheters has been demonstrated to be safe and effective in the treatment of atrioventricular nodal reentrant tachycardia (AVNRT) in pediatric patients, albeit with a higher rate of clinical recurrence. Limited information is available regarding efficacy, mid-term outcomes, and complications related to the use of the 8-mm Freezor Max Cryoablation catheter (Medtronic, Minneapolis, MN, USA) in pediatric patients.

Methods: We performed a retrospective review of all pediatric patients with normal cardiac anatomy who underwent an ablation procedure for treatment of AVNRT using the 8-mm tip Cryoablation catheter at three large pediatric academic arrhythmia centers.

Tachyarrhythmias after pediatric heart transplantation.

Background: Tachyarrhythmias in pediatric post-heart transplant patients are not well defined. In this study we sought to further characterize these arrhythmias in terms of presentation, course, and outcome.

Methods: This investigation was a retrospective review of heart transplant recipients at St.

Cardiac resynchronization therapy in pediatric congenital heart disease: insights from noninvasive electrocardiographic imaging.

Background: Electrocardiographic imaging (ECGI) is a novel electrophysiologic imaging modality that may help guide patient selection and lead placement for cardiac resynchronization therapy (CRT).

Objective: The purpose of this study was to apply noninvasive ECGI to pediatric heart failure patients with congenital heart disease (CHD) undergoing evaluation for CRT.

Methods: ECGI was applied in eight patients with CHD who were either being evaluated for CRT or undergoing CRT.

Therapeutic options in hypertrophic cardiomyopathy: a pediatric perspective.

Hypertrophic cardiomyopathy (HCM) is the most prevalent genetic cardiomyopathy in children and young adults. Despite advances in understanding the molecular etiology of this disorder, the clinical phenotypes vary widely from asymptomatic septal hypertrophy, to frank congestive heart failure due to left ventricular outflow tract obstruction (LVOTO), to unexpected sudden cardiac death. Thus, isolating a specific genetic defect in this disease does little to predict the clinical consequence.

Cardiac memory in patients with Wolff-Parkinson-White syndrome: noninvasive imaging of activation and repolarization before and after catheter ablation.

Background: Cardiac memory refers to a change in ventricular repolarization induced by and persisting for minutes to months after cessation of a period of altered ventricular activation (eg, resulting from pacing or preexcitation in patients with Wolff-Parkinson-White syndrome). ECG imaging (ECGI) is a novel imaging modality for noninvasive electroanatomic mapping of epicardial activation and repolarization.

Methods And Results: Fourteen pediatric patients with Wolff-Parkinson-White syndrome and no other congenital disease, were imaged with ECGI a day before and 45 minutes, 1 week, and 1 month after successful catheter ablation.

A fatal device-device interaction between a wearable automated defibrillator and a unipolar ventricular pacemaker.

We report a fatal device-device interaction between a wearable automated defibrillator (WAD; LifeVest - LifeCor, Inc., Pittsburgh, PA, USA) and a unipolar pacemaker that occurred in an 18-year-old patient listed for cardiac transplantation due to his failing Fontan. The patient developed ventricular tachycardia that was initially detected by the WAD.

Markers of coronary sinus accessory pathways in pediatrics.

Introduction: Coronary sinus accessory pathways (CSAPs), atrioventricular connections formed by the coronary sinus myocardial coat, have been described in adult patients, but not systematically described in pediatric patients.

Methods: Patients who underwent CSAP ablation were compared to patients with right posteroseptal (RPS) pathway ablation (control group) from November 2004 to June 2007. Retrospective reviews of preablation 12-lead electrocardiogram (EKG), fluoroscopic, and intracardiac electrogram data were then performed to identify electrophysiologic markers of CSAP.

Hypertrophic cardiomyopathy with preexcitation: insights from noninvasive electrocardiographic imaging (ECGI) and catheter mapping.

Unlabelled: Hypertrophic Cardiomyopathy and Preexcitation.

Introduction: Fasciculoventricular pathway has been described as an unusual variant of preexcitation. Electrocardiographic imaging (ECGI) is a novel imaging modality for noninvasive electroanatomic mapping of epicardial activation and repolarization.

Alternative delivery of a 4Fr lumenless pacing lead in children.

Background: The potential advantages of using a 4Fr lumenless pacing lead (3830 SelectSecure, Medtronic Inc, Minneapolis, MN, USA) in children are largely negated due to the large size of the delivery system. Here we describe an innovative, sheath guided, delivery technique using conventional 5F sheaths.

Methods: Transvenous access was obtained via the left cephalic or axillary vein.

Experience and results during transition from radiofrequency ablation to cryoablation for treatment of pediatric atrioventricular nodal reentrant tachycardia.

Background: Cryoablation has emerged as a new, theoretically safer, modality for treating atrioventricular nodal reentrant tachycardia (AVNRT). The purpose of this study is to compare procedural aspects and outcomes during the transition from radiofrequency (RF) ablation to cryoablation for pediatric AVNRT.

Methods: Data were obtained retrospectively from 80 consecutive pediatric patients who underwent AVNRT ablation from 10/2001- 4/2006 (RF n = 42, Cryo n = 38).

Electrocardiographic diagnosis of myocardial ischemia in children: is a diagnostic electrocardiogram always diagnostic?

Electrocardiographic criteria for the diagnosis of cardiac ischemia in adults are well defined; however, analogous criteria for the diagnosis of cardiac ischemia in infants and children remain ambiguous. The difficulty in defining electrocardiographic criteria in pediatrics relates to age-dependent differences in the pediatric electrocardiogram, the presence or absence of congenital heart disease, and multiple and diverse etiologies of myocardial injury that lead to an ischemic pattern on the electrocardiogram. In this report, we illustrate 3 pediatric cases in which the electrocardiogram met adult diagnostic criteria for acute transmural myocardial infarction, without coronary artery abnormalities in 2 cases and with a transient coronary abnormality in the third.

Cryoablation of accessory pathways in the coronary sinus in young patients: a multicenter study from the Pediatric and Congenital Electrophysiology Society's Working Group on Cryoablation.

Introduction: This is a multicenter retrospective study evaluating the immediate- and mid-term outcomes of cryoablation of accessory pathways in the coronary sinus in children or in patients with congenital heart disease.

Methods And Results: Twenty-one patients (median age 13.0 years, range 2-40) from six institutions were included.

Sudden death prior to pediatric heart transplantation: would implantable defibrillators improve outcome?

Objectives: The goal of this study is to determine the incidence of sudden cardiac death in children with cardiomyopathy prior to pediatric heart transplantation.

Background: Recent primary prevention trials of implantable cardiac defibrillator (ICD) therapy in adults with ischemic and non-ischemic cardiomyopathy have shown a survival benefit. The incidence of sudden death, and thus the likelihood of improved survival with ICD therapy, in children with cardiomyopathy is currently unknown.