Cardiac Involvement in LAMA2-Related Muscular Dystrophy and SELENON-Related Congenital Myopathy: A Case Series.

Background: LAMA2-related muscular dystrophy (LAMA2-MD) and SELENON-related myopathy (SELENON-RM) are two rare neuromuscular diseases characterized by proximal and axial muscle weakness, scoliosis, spinal rigidity, low bone quality and respiratory impairment. Cardiac involvement has previously been described in retrospective studies and case reports, but large case series and prospective studies in unselected cohorts are lacking.

Objective: The objective of this study is to conduct prevalence estimations, perform cardiac phenotyping, and provide recommendations for clinical care.

Comparing adolescent- and adult-onset unexplained cardiac arrest: Results from the Dutch Idiopathic VF Registry.

Background: Current cohorts of patients with idiopathic ventricular fibrillation (IVF) primarily include adult-onset patients. Underlying causes of sudden cardiac arrest vary with age; therefore, underlying causes and disease course may differ for adolescent-onset vs adult-onset patients.

Objective: The purpose of this study was to compare adolescent-onset with adult-onset patients having an initially unexplained cause of VF.

The arrhythmogenic cardiomyopathy phenotype associated with PKP2 c.1211dup variant.

Background: The arrhythmogenic cardiomyopathy (ACM) phenotype, with life-threatening ventricular arrhythmias and heart failure, varies according to genetic aetiology. We aimed to characterise the phenotype associated with the variant c.1211dup (p.

Comparison and predictors of implantable cardioverter-defibrillator therapy for primary and secondary prevention.

Background: Implantable cardioverter-defibrillators (ICDs) are effective in detecting and treating ventricular arrhythmias. Studies on ICD therapy for different indications (primary and secondary prevention) and possible predictors of ICD therapy are limited. In this study, the incidence and type of ICD therapy were related to the indication and the underlying cardiac pathology.

Importance of Systematic Diagnostic Testing in Idiopathic Ventricular Fibrillation: Results From the Dutch iVF Registry.

Background: Idiopathic ventricular fibrillation (iVF) is a diagnosis of exclusion. Systematic diagnostic testing is important to exclude alternative causes for VF. The early use of "high yield" testing, including cardiac magnetic resonance (CMR), exercise testing, and sodium channel blocker provocation, has been increasingly recognized.

Conduction System Pacing Versus Conventional Cardiac Resynchronization Therapy in Congenital Heart Disease.

Background: Dyssynchrony-associated left ventricular systolic dysfunction is a major contributor to heart failure in congenital heart disease (CHD). Although conventional cardiac resynchronization therapy (CRT) has shown benefit, the comparative efficacy of cardiac conduction system pacing (CSP) is unknown.

Objectives: The purpose of this study was compare the clinical outcomes of CSP vs conventional CRT in CHD with biventricular, systemic left ventricular anatomy.

Myotonic dystrophy type 1: A comparison between the adult- and late-onset subtype.

Introduction/aims: Although the extent of muscle weakness and organ complications has not been well studied in patients with late-onset myotonic dystrophy type 1 (DM1), adult-onset DM1 is associated with severe muscle involvement and possible life-threatening cardiac and respiratory complications. In this study we aimed to compare the clinical phenotype of adult-onset vs late-onset DM1, focusing on the prevalence of cardiac, respiratory, and muscular involvement.

Methods: Data were prospectively collected in the Dutch DM1 registry.

Cardiac Resynchronization Therapy for Adult Patients With a Failing Systemic Right Ventricle: A Multicenter Study.

Background The objective of this international multicenter study was to investigate both early and late outcomes of cardiac resynchronization therapy (CRT) in patients with a systemic right ventricle (SRV) and to identify predictors for congestive heart failure readmissions and mortality. Methods and Results This retrospective international multicenter study included 13 centers. The study population comprised 80 adult patients with SRV (48.

Prevalence of Mitral Annulus Disjunction and Mitral Valve Prolapse in Patients With Idiopathic Ventricular Fibrillation.

Background Idiopathic ventricular fibrillation (IVF) is diagnosed in patients with ventricular fibrillation of which the origin is not identified after extensive evaluations. Recent studies suggest an association between mitral annulus disjunction (MAD), mitral valve prolapse (MVP), and ventricular arrhythmias. The prevalence of MAD and MVP in patients with IVF in this regard is not well established.

Rationale and Design of the ISOLATION Study: A Multicenter Prospective Cohort Study Identifying Predictors for Successful Atrial Fibrillation Ablation in an Integrated Clinical Care and Research Pathway.

Introduction: Continuous progress in atrial fibrillation (AF) ablation techniques has led to an increasing number of procedures with improved outcome. However, about 30-50% of patients still experience recurrences within 1 year after their ablation. Comprehensive translational research approaches integrated in clinical care pathways may improve our understanding of the complex pathophysiology of AF and improve patient selection for AF ablation.

An evaluation of 24 h Holter monitoring in patients with myotonic dystrophy type 1.

Aims: To evaluate the clinical effectiveness of routine 24 h Holter monitoring to screen for conduction disturbances and arrhythmias in patients with myotonic dystrophy type 1 (DM1).

Methods And Results: A retrospective two-centre study was conducted including DM1-affected individuals undergoing routine cardiac screening with at least one 24 h Holter monitoring between January 2010 and December 2020. For each individual, the following data were collected: Holter results, results of electrocardiograms (ECGs) performed at the same year as Holter monitoring, presence of cardiac complaints, and neuromuscular status.

Electrocardiographic predictors of infrahissian conduction disturbances in myotonic dystrophy type 1.

Aims: The aim of this study was to determine electrocardiographic (ECG) criteria predicting abnormal infrahissian conduction in patients with myotonic dystrophy type 1 (DM1), as these criteria could be used to identify the need for an electrophysiological study (EPS).

Methods And Results: A retrospective multicentre study was conducted including DM1-affected individuals who underwent EPS between 2007 and 2018. For each individual, EPS indication, His-ventricle (HV) interval, resting ECG parameters prior to EPS, left ventricular ejection fraction (LVEF), neurological status, and DM1 DNA analysis results were collected.

Atrial fibrillation in patients with an atrial septal defect in a single centre cohort during a long clinical follow-up: its association with closure and outcome of therapy.

Objective: Currently, consensus is lacking on the relation between closure of atrial septal defect (ASD) and the incidence of atrial fibrillation (AF), which is a known complication in ASD patients. More importantly, studies reporting on the treatment applied for AF in ASD patients are scarce. The aims of this study were (1) to assess the incidence of AF in ASD patients, (2) to study the relation between closure and AF and (3) to evaluate applied treatment strategies.

Arrhythmogenic Right Ventricular Cardiomyopathy in a Pediatric Patient.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is rarely diagnosed in childhood. We describe the case of a 9-year-old girl with genetically confirmed ARVC who presented with syncope, ventricular arrhythmia, and biventricular myocardial dysfunction. This case highlights the need for development of pediatric ARVC diagnosis criteria specific for pediatric patients and discusses potential diagnostic improvement using echocardiographic deformation imaging.

Concomitant pulmonary vein isolation and percutaneous closure of atrial septal defects: A pilot project.

Background: Patients with an atrial septal defect (ASD) are at increased risk of developing atrial fibrillation (AF). Currently percutaneous ASD closure is the preferred therapeutic strategy and although pulmonary vein isolation (PVI) for AF is feasible after ASD closure, the transseptal puncture can be technically challenging and probably increases the perioperative risk. A staged approach, with PVI several months before ASD closure, has been recommended for patients already scheduled for closure, but no data are available on combined procedures.

Dysrhythmias in patients with a complete atrioventricular septal defect: From surgery to early adulthood.

Objective: Outcomes after surgical repair of complete atrioventricular septal defect (cAVSD) have improved. With advancing age, the risk of development of dysrhythmias may increase. The aims of this study were to (1) examine development of sinus node dysfunction (SND), atrial and ventricular tachyarrhythmias, and (2) study progression of atrioventricular conduction abnormalities in young adult patients with repaired cAVSD.

Second-generation cryoballoon ablation for recurrent atrial fibrillation after an index cryoballoon procedure: a staged strategy with variable balloon size.

Purpose: Currently, information on the optimal approach of redo procedures for paroxysmal atrial fibrillation (PAF) is limited. Radiofrequency ablation is the preferred technique, with reported success rates of 50-70% at 1-2 years, whereas only few reports exist on redo cryoballoon (CB) ablations. We describe outcomes on a systematic approach of repeat procedures with a second-generation cryoballoon (CB-2) after a successful index CB ablation.

Time course and interrelationship of dysrhythmias in patients with surgically repaired atrial septal defect.

Background: Atrial fibrillation (AF) and other supraventricular tachycardias (SVTs) are known complications after surgical repair of atrial septal defect (ASD), but sinus node dysfunction (SND) and complete atrioventricular conduction block (cAVB) may also occur.

Objective: The aim of this study was to examine time course and interrelationship of various dysrhythmias in patients with ASD.

Methods: Adult patients (N = 95) with surgically repaired secundum ASD (n = 40), partial atrioventricular septal defect (n = 37) or sinus venosus defect (n = 18), and documented SND, cAVB, AF, and/or other SVT were included.

Scar Characterization to Predict Life-Threatening Arrhythmic Events and Sudden Cardiac Death in Patients With Cardiac Resynchronization Therapy: The GAUDI-CRT Study.

Objectives: The aim of this study was to analyze whether scar characterization could improve the risk stratification for life-threatening ventricular arrhythmias and sudden cardiac death (SCD).

Background: Among patients with a cardiac resynchronization therapy (CRT) indication, appropriate defibrillator (CRT-D) therapy rates are low.

Methods: Primary prevention patients with a class I indication for CRT were prospectively enrolled and assigned to CRT-D or CRT pacemaker according to physician's criteria.

Usefulness of Fragmented QRS Complexes in Patients With Congenital Heart Disease to Predict Ventricular Tachyarrhythmias.

Fragmented QRS complexes (fQRS) on 12-lead electrocardiogram are known predictors of ventricular tachyarrhythmia (VTA) in patients with coronary artery disease. There is limited knowledge of the clinical implications of fQRS in patients with congenital heart defects (CHD). Aims of this study were to examine (1) the occurrence of fQRS in patients with various types of CHD and (2) whether fQRS is associated with development of VTA.

Frequent atrial extrasystolic beats predict atrial fibrillation in patients with congenital heart defects.

Aims: Atrial fibrillation (AF) is increasingly observed in patients with congenital heart defects (CHDs) who survive nowadays into adulthood. Yet, predictors of AF are scarce in this high-risk population. This study therefore examined the predictive ability of atrial extrasystole (AES) for development of AF in CHD patients.

Substrate modification or ventricular tachycardia induction, mapping, and ablation as the first step? A randomized study.

Background: The role and optimal sequence of ventricular tachycardia (VT) induction, mapping, and ablation when combined with substrate modification is unclear.

Objective: The purpose of this study was to test the benefits of starting the scar-related VT ablation procedure with substrate modification vs the standard protocol of VT induction, mapping, and ablation as the first step.

Methods: Forty-eight consecutive patients with structural heart disease and clinical VTs were randomized to simplified substrate ablation procedure with scar dechanneling as the first step (group 1, n = 24) or standard procedure with VT induction, mapping, and ablation followed by scar dechanneling (group 2, n = 24).

Dyssynchronization reduces dynamic obstruction without affecting systolic function in patients with hypertrophic obstructive cardiomyopathy: a pilot study.

Dyssynchrony from biventricular pacing (BiV) can reduce dynamic obstruction in hypertrophic obstructive cardiomyopathy (HOCM), but its consequences on the left ventricular (LV) systolic function are unknown. We evaluate changes in LV systolic function and assess the effectiveness of BiV in HOCM. Thirteen patients with HOCM (55 [33/75] years, five males) received a BiV device and underwent 2D transthoracic echocardiography before the implantation and at 12 months follow-up.

Non-sustained ventricular tachycardia in patients with congenital heart disease: An important sign?

Background: Sustained ventricular tachycardia (susVT) and ventricular fibrillation (VF) are observed in adult patients with congenital heart disease (CHD). These dysrhythmias may be preceded by non-sustained ventricular tachycardia (NSVT). The aims of this study are to examine the 1] time course of ventricular tachyarrhythmia (VTA) in a large cohort of patients with various CHDs and 2] the development of susVT/VF after NSVT.