Risk stratification in arrhythmogenic right ventricular dysplasia/cardiomyopathy-associated desmosomal mutation carriers.

Background: We investigated the role of phenotypic characteristics in stratifying the risk of sustained ventricular arrhythmias in patients harboring arrhythmogenic right ventricular dysplasia/cardiomyopathy-associated mutations.

Methods And Results: Clinical, electrocardiographic, and arrhythmic outcome (composite measure of first occurrence of sustained ventricular tachycardia/resuscitated sudden cardiac death/sudden cardiac death/appropriate implantable cardioverter-defibrillator therapy) data were obtained for 215 patients (104 families; 85% PKP-2). During a mean follow-up of 7 years, 86 (40%) patients experienced the arrhythmic outcome.

Cardiac magnetic resonance T1 mapping of left atrial myocardium.

Background: Cardiac magnetic resonance (CMR) T1 mapping is an emerging tool for objective quantification of myocardial fibrosis.

Objectives: To (a) establish the feasibility of left atrial (LA) T1 measurements, (b) determine the range of LA T1 values in patients with atrial fibrillation (AF) vs healthy volunteers, and (c) validate T1 mapping vs LA intracardiac electrogram voltage amplitude measures.

Methods: CMR imaging at 1.

First experience with a novel robotic remote catheter system: Amigo™ mapping trial.

Introduction: Amigo™ (Catheter Robotics, Inc., Mount Olive, NJ) remote catheter system (RCS) was designed to provide a simple and relatively inexpensive system for remote catheter manipulation. The purpose of this study was to evaluate the performance and safety of Amigo in mapping the right side of the heart.

Feasibility of image-based simulation to estimate ablation target in human ventricular arrhythmia.

Background: Previous studies suggest that magnetic resonance imaging with late gadolinium enhancement (LGE) may identify slowly conducting tissues in scar-related ventricular tachycardia (VT).

Objective: To test the feasibility of image-based simulation based on LGE to estimate ablation targets in VT.

Methods: We conducted a retrospective study in 13 patients who had preablation magnetic resonance imaging for scar-related VT ablation.

The effect of antiarrhythmic medication management on atrial fibrillation ablation outcomes.

Background: Patients commonly present for atrial fibrillation (AF) ablation while taking antiarrhythmic (AA) medications. It is unknown if AA use at the time of ablation affects procedural outcome. This study compares the AF ablation outcomes of patients who underwent ablation while on AA medications to those who were not on AA medications.

Significance of leukocytosis after cardiac device implantation.

Infection remains a feared complication after cardiac device implantation. Whether early postprocedural leukocytosis, a recognized marker of infection, is an indicator of impending infection is unclear and was the focus of this study. A retrospective chart review of consecutive patients who underwent implantable cardioverter defibrillator or pacemaker implantation was performed.

Arrhythmogenic right ventricular dysplasia.

Arrhythmogenic right ventricular dysplasia (ARVD) is an inherited cardiomyopathy and is also called ARVD/C. In most cases, ARVD is inherited in an autosomal-dominant pattern and clinically is characterized by ventricular arrhythmias with an increased risk of sudden death. Although it is prominently a disease of the right ventricle (RV), involvement of the left ventricle is not uncommon.

Impact of Obstructive Sleep Apnea on Outcomes of Catheter Ablation of Atrial Fibrillation.

Unlabelled: Obstructive sleep apnea (OSA) is a growing epidemic in the United States and significantly contributes to the increasing prevalence of atrial fibrillation (AF) in the U.S.

Population: Although a strong correlation between OSA and AF has been demonstrated, a causal relationship between these two conditions has not been definitively established.

Catheter Ablation of Atrial Fibrillation to Maintain Sinus Rhythm.

Catheter ablation of atrial fibrillation (AF) is an important treatment modality for patients with AF. Although the superiority of catheter ablation of AF over antiarrhythmic drug therapy has been demonstrated in middle aged patients with paroxysmal AF, the role of catheter ablation in other patient subgroups, particularly in the elderly, those with heart failure, and those with long standing persistent AF has not been as well defined. Furthermore, although AF ablation can be performed with reasonable efficacy and safety in experienced hands, late recurrences of AF a year or more following AF ablation are not uncommon.

Catheter Ablation of Long Standing Persistent Atrial Fibrillation: Lessons Learned.

Atrial fibrillation has evolved from being a novel unproven procedure to being an important treatment option for patients with symptomatic atrial fibrillation. Atrial fibrillation ablation is an appropriate treatment option for patients with symptomatic atrial fibrillation, particularly if they have failed one or more trials of antiarrhythmic drug therapy. While much has been learned about the optimal technique and outcomes for catheter ablation of paroxysmal atrial fibrillation; catheter ablation of atrial fibrillation in patients with long standing persistent atrial fibrillation remains in its infancy.

The stability of electrically induced ventricular fibrillation.

The first recorded heart rhythm for cardiac arrest patients can either be ventricular fibrillation (VF) which is treatable with a defibrillator, or asystole or pulseless electrical activity (PEA) which are not. The time course for the deterioration of VF to either asystole or PEA is not well understood. Knowing the time course of this deterioration may allow for improvements in emergency service delivery.

Defibrillation success rates for electrically-induced fibrillation: hair of the dog.

Accidental electrocutions kill about 1000 individuals annually in the USA alone. There has not been a systematic review or modeling of elapsed time duration defibrillation success rates following electrically-induced VF. With such a model, there may be an opportunity to improve the outcomes for industrial electrocutions and further understand arrest-related-deaths where a TASER(®) electrical weapon was involved.

Studying arrhythmogenic right ventricular dysplasia with patient-specific iPSCs.

Cellular reprogramming of somatic cells to patient-specific induced pluripotent stem cells (iPSCs) enables in vitro modelling of human genetic disorders for pathogenic investigations and therapeutic screens. However, using iPSC-derived cardiomyocytes (iPSC-CMs) to model an adult-onset heart disease remains challenging owing to the uncertainty regarding the ability of relatively immature iPSC-CMs to fully recapitulate adult disease phenotypes. Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited heart disease characterized by pathological fatty infiltration and cardiomyocyte loss predominantly in the right ventricle, which is associated with life-threatening ventricular arrhythmias.

A family with a complex clinical presentation characterized by arrhythmogenic right ventricular dysplasia/cardiomyopathy and features of branchio-oculo-facial syndrome.

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a familial form of cardiomyopathy typically caused by mutations in genes that encode an element of the cardiac desmosome. Branchio-oculo-facial syndrome (BOFS) is a craniofacial disorder caused by TFAP2A mutations. In a family segregating ARVD/C, some members also had features of BOFS.

High prevalence of catecholamine-facilitated focal ventricular tachycardia in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy.

Background: Exercise-related ventricular tachycardia (VT) and high burden of premature ventricular contractions (PVCs) are common in arrhythmogenic right ventricular dysplasia/cardiomyopathy. We hypothesized that VT in arrhythmogenic right ventricular dysplasia/cardiomyopathy shows a high degree of association with the PVC at baseline.

Methods And Results: The study population included 16 consecutive arrhythmogenic right ventricular dysplasia/cardiomyopathy patients with recurrent VT who underwent catheter ablation.

An electrocardiographic scoring system for distinguishing right ventricular outflow tract arrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy from idiopathic ventricular tachycardia.

Background: Ventricular arrhythmias in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and idiopathic ventricular tachycardia (VT) can share a left bundle branch block/inferior axis morphology. We previously reported electrocardiogram characteristics during outflow tract ventricular arrhythmias that helped distinguish VT related to ARVD/C from idiopathic VT.

Objective: To prospectively validate these criteria.

Myocardial structural associations with local electrograms: a study of postinfarct ventricular tachycardia pathophysiology and magnetic resonance-based noninvasive mapping.

Background: The association of scar on late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) with local electrograms on electroanatomic mapping has been investigated. We aimed to quantify these associations to gain insights regarding LGE-CMR image characteristics of tissues and critical sites that support postinfarct ventricular tachycardia (VT).

Methods And Results: LGE-CMR was performed in 23 patients with ischemic cardiomyopathy before VT ablation.

Predictors of high defibrillation threshold in the modern era.

Introduction: High defibrillation threshold (DFT) is a clinical problem in 1-8% of implantable cardioverter-defibrillator implants. Some clinicians and investigators question whether the benefits of routine DFT testing outweigh the risks. Identification of the predictors of elevated DFT may allow selective application of DFT testing.

Initial experience with magnetic resonance imaging of atrial scar and co-registration with electroanatomic voltage mapping during atrial fibrillation: success and limitations.

Background: Ablation for atrial fibrillation (AF) frequently requires multiple procedures to achieve durable restoration of sinus rhythm. Early studies have suggested that delayed enhancement magnetic resonance imaging (DE-MRI) of the left atrium (LA) can assist in performing repeat ablation procedures.

Objective: The purpose of this study was to investigate the utility of DE-MRI in delineating regions of LA low voltage and PV reconnection sites in patients undergoing repeat PV isolation for recurrent AF.

A proposal for new clinical concepts in the management of atrial fibrillation.

Atrial fibrillation (AF) represents a growing public health burden. It is a complex condition, involving a number of etiologic factors and arrhythmia mechanisms associated with atrial remodeling. Greater understanding of these mechanisms may improve therapy.

Atrial Fibrillation Ablation in Obese Patients.

Despite the increased burden of atrial fibrillation (AF), obese patients have similar, if not slightly improved, mortality, described as the "obesity paradox." Catheter ablation for AF in obese patients is a reasonable option, but patients should be screened for sleep apnea and counseled about the possibility of longer procedure times and repeat procedures to achieve similar success rates. Quality of life will likely improve after successful ablation.

Catheter Ablation of Atrial Fibrillation - Techniques and Technology.

For certain patients with atrial fibrillation (AF) catheter ablation is now an important, therapeutic, intervention. It is established that catheter ablation is more effective than antiarrhythmic drug therapy at maintaining middle-aged patients with paroxysmal AF in sinus rhythm. However, the role of catheter ablation in other patient groups is not yet well defined.