Very low-dose Everolimus therapy diminishes cardiac tumours in tuberous sclerosis complex disease.

Tuberous sclerosis complex is syndrome that affects several organs. Cardiac manifestations include rhabdomyoma, which could lead to intracardiac obstruction of blood flow. In the present case, the so far lowest documented Everolimus blood level of 2-3 ng/ml led to tumour regression.

Isolated loss of vaccine immunity in the protein losings syndrome in a patient with a reverse one and a half ventricle palliation ("failing Fontan-like physiology").

Background: A subgroup of CHDs can only be treated palliatively through a Fontan circulation. In case of a failing Fontan situation, serum proteins are lost unspecifically and can also lead to a loss of vaccine antibodies. In a failing Fontan situation, heart transplantation may be the only feasible option.

Efficacy and Safety of Esmolol in Neonatal Cardiac Surgery with Cardiopulmonary Bypass (CPB) for d-Transposition of the Great Arteries (d-TGA).

Objective: D-Transposition of the great arteries (d-TGA) is the most common congenital heart disease requiring surgical correction within the neonatal period. Sinus tachycardia often persists postoperatively, potentially affecting cardiac function. This study aimed to investigate the efficacy and safety of the short-acting beta-1-selective beta-blocker esmolol in controlling heart rate in neonatal cardiac surgery with cardiopulmonary bypass (CPB).

An international multicenter cohort study on implantable cardioverter-defibrillators for the treatment of symptomatic children with catecholaminergic polymorphic ventricular tachycardia.

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) may cause sudden cardiac death (SCD) despite medical therapy. Therefore, implantable cardioverter-defibrillators (ICDs) are commonly advised. However, there is limited data on the outcomes of ICD use in children.

Differences in Androgen Receptor Expression in Human Heart Tissue in Various Types of Cardiomyopathy and in Aortic Valve Stenosis.

: Sex-specific differences in heart disease outcomes are influenced by the levels of the steroid hormones, estrogen and testosterone. While the roles of estrogen receptors in cardiac disease are well-studied in animals and humans, respective research on androgen receptors (AR) is limited. Here we investigate AR protein and mRNA expression in human myocardium of various cardiac diseases.

Leadless epicardial pacing at the left ventricular apex: an animal study.

Aims: State-of-the-art pacemaker implantation technique in infants and small children consists of pace/sense electrodes attached to the epicardium and a pulse generator in the abdominal wall with a significant rate of dysfunction during growth, mostly attributable to lead failure. In order to overcome lead-related problems, feasibility of epicardial implantation of a leadless pacemaker at the left ventricular apex in a growing animal model was studied.

Methods And Results: Ten lambs (median body weight 26.

Contact force guided radiofrequency current application at developing myocardium.

Introduction: Catheter contact is a key determinant for lesion size in radiofrequency catheter ablation (RFA). Monitoring of contact force (CF) during RFA has been shown to improve efficacy of RFA in experimental settings as well as in adult patients. Coronary artery narrowing after RFA has been described in experimental settings as well as in children and adults and may be dependent from catheter contact.

Repeat radiofrequency catheter ablation of atrial tachycardias in patients with congenital heart disease.

Introduction: Atrial tachycardias (AT) in patients with congenital heart disease (CHD) are significantly contributing to morbidity and mortality. Aim of this study was to evaluate the long-term course of CHD patients requiring repeat ablation procedures (RAP) of AT.

Patients And Methods: All 144 patients with CHD who had undergone ablation of AT at our center between January 2003 and October 2018 were enrolled.

Evaluation of age at symptom onset, proband status, and sex as predictors of disease severity in pediatric catecholaminergic polymorphic ventricular tachycardia.

Background: Children with catecholaminergic polymorphic ventricular tachycardia (CPVT) are at risk for sudden death, and a risk stratification tool does not exist.

Objective: The purpose of this study was to determine whether proband status, age at symptom onset, and/or sex are independent predictors of cardiac events.

Methods: A multicenter, ambispective, cohort of pediatric CPVT patients was categorized by sex, proband status, and age at symptom onset (D1: first decade of life [symptom onset <10 years] or D2: second decade of life [symptom onset 10-18 years, inclusive]).

Safety of Transseptal Puncture for Access to the Left Atrium in Infants and Children.

Transseptal puncture (TSP) is a standard procedure to obtain access to the left heart. However, data on TSP in infants and children particularly with congenital heart defects (CHD) is sparse. Safety and efficacy of TSP in infants and children < 18 years with normal cardiac anatomy and with CHD were assessed.

Lone Atrial Flutter in Children and Adolescents: Is It Really "Lone"?

Atrial flutter (AFL) in children and adolescents beyond the neonatal period in the absence of any underlying myocardial disease ("lone AFL") is rare and data is limited. Our study aims to present clinical and electrophysiological data of presumed "lone AFL" in pediatric patients and discuss the role of endomyocardial biopsy (EMB) and further follow-up. Since July 2005, eight consecutive patients at a median age of 12.

Epicardial implantation of a leadless pacemaker in a lamb model.

Background: Pacemaker used in small children typically consist of an abdominally placed generator and epicardially affixed leads, making such a system prone to lead dysfunction during growth. Aim of this study was to investigate the feasibility of epicardial pacing with a leadless pacemaker in a lamb model.

Animals And Methods: Seventeen lambs underwent epicardial implantation of a Micra transcatheter pacing system (TPS) (Medtronic, Minneapolis, MN, USA) via left-lateral thoracotomy to the left ventricle (LV) surface (n = 11/17) and to the left atrial appendage (n = 6).

Value of defibrillation threshold testing in children with nontransvenous implantable cardioverter defibrillators: Are routine DFT tests indicated?

Background: Nontransvenous implanted cardioverter defibrillators (NT-ICD) are used in infants and small children with life-threatening ventricular tachyarrhythmias. With growth, shock vector shift may result in increase of defibrillation threshold (DFT) and fatal ICD failure.

Objectives: To date, the only way to verify ICD function in children with NT-ICD is repetitive DFT testing, which is potentially harmful and may even be life threatening.

High density mapping and catheter ablation of atrial tachycardias in adults with congenital heart disease.

Aims: We used a new grid-style multi-electrode mapping catheter (Advisor™ HD Grid, Abbott) and investigated its use for high density mapping of atrial tachycardias in adult patients with congenital heart disease.

Patients And Methods: All patients with congenital heart disease who had mapping of atrial tachycardias using the new grid-style catheter between March 2018 and April 2019 were included.

Results: A total of 24 adult patients had high density mapping of atrial tachycardias using the grid-style multi-electrode catheter.

Double cryoenergy application (freeze-thaw-freeze) at growing myocardium: Lesion volume and effects on coronary arteries late after energy application. Implications for efficacy and safety in pediatric patients.

Introduction: Cryoenergy is accepted as an alternative to radiofrequency ablation (RFA) in childen for ablation of supraventricular tachycardia substrates. Single cryoenergy application has been shown to be inferior to RFA. Double cryoenergy application has therefore been introduced into clinical practice, but experience concerning efficacy is limited.

Transvenous and non-transvenous implantable cardioverter-defibrillators in children, adolescents, and adults with congenital heart disease: who is at risk for appropriate and inappropriate shocks?

Aims: Non-transvenous implantable cardioverter-defibrillators (ICDs) as used in small patients and in patients with congenital heart disease (CHD) have not been compared with transvenous systems with respect to safety and efficacy yet. Aim of the present study was to describe the prevalence of and to identify contributing factors for appropriate and inappropriate ICD discharges in patients with non-transvenous and transvenous ICD.

Methods And Results: Single centre analysis of all paediatric and CHD patients who had received an ICD since 1995.

Efficacy and safety of non-transvenous cardioverter defibrillators in infants and young children.

Background: Implantable cardioverter defibrillators (ICD) protect from sudden cardiac death (SCD). In infants and young children, ICD implantation and programming is challenging due to small body size, elevated heart rates, and high physical activity.

Purpose: We report our experience applying a non-transvenous ICD (NT-ICD) system to infants and children < 12 years of age and < 45-kg body weight.

Long-Term Follow-Up After Radiofrequency Catheter Ablation of Accessory Atrioventricular Pathways in Children.

Objectives: The purpose of this study was to evaluate long-term safety and efficacy of catheter ablation of accessory atrioventricular pathways (AP) in a pediatric cohort.

Background: Radiofrequency catheter ablation of accessory AP is the recommended treatment for patients with atrioventricular re-entrant tachycardia. Data on long-term results ≥1 year after AP ablation in pediatric patients is sparse.

Radiofrequency Catheter Ablation of Atrial Tachycardias in Congenital Heart Disease: Results With Special Reference to Complexity of Underlying Anatomy.

Background: Radiofrequency catheter ablation has become the treatment strategy of choice for atrial tachyarrhythmias in patients with congenital heart disease (CHD). We analyzed results of radiofrequency catheter ablation in a large cohort of patients with CHD with special reference to complexity of underlying anatomy.

Methods And Results: One hundred and forty-four patients with CHD and atrial tachyarrhythmias undergoing radiofrequency catheter ablation were classified according to complexity of underlying CHD: simple CHD, n=18 (12%); moderate CHD, n=53 (37%); and complex CHD, n=73 (51%).

Effects of Triple Cryoenergy Application on Lesion Formation and Coronary Arteries in the Developing Myocardium.

To improve long-term outcome after cryoablation of substrates of supraventricular tachycardia, application of two and three consecutive freeze-thaw cycles has been performed. The effect of triple freeze-thaw cycles on lesion formation within developing myocardium and coronary arteries, however, has not been studied yet. In eight piglets (mean age 15 weeks, weight 15-20 kg), 30 cryolesions (three consecutive freeze-thaw cycles) were applied to the atrial aspect of both AV valve annuli (n = 18) as well as to ventricular myocardium below the valves (n = 12).

Long-Term Follow-Up After Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia in Children.

Background: Catheter ablation of the slow conducting pathway (SP) is treatment of choice for atrioventricular nodal reentrant tachycardia (AVNRT). Although there are abundant data on AVNRT ablation in adult patients, little is known about the long-term results ≥3 years after AVNRT ablation in pediatric patients.

Methods And Results: Follow-up data from 241 patients aged ≤18 years who had undergone successful AVNRT ablation were analyzed.

Internal Cardioverter Defibrillator Indications and Therapies after Atrial Baffle Procedure for d-Transposition of the Great Arteries: A Multicenter Analysis.

Background: Sudden cardiac death (SCD) is the most important cause of late mortality after atrial baffle procedure for d-transposition of the great arteries (d-TGA). Experience with internal cardioverter defibrillator (ICD) therapy in this population is limited. We conducted a multicenter cohort study to determine the current state of ICD therapy in individuals after atrial baffle procedure.