Sex Differences in the Clinical Presentation and Natural History of Dilated Cardiomyopathy.

Background: Biological sex has a diverse impact on the cardiovascular system. Its influence on dilated cardiomyopathy (DCM) remains unresolved.

Objectives: This study aims to investigate sex-specific differences in DCM presentation, natural history, and prognostic factors.

Conduction system pacing learning curve: Left bundle pacing compared to His bundle pacing.

Introduction: Conduction system pacing (CSP), consisting of His bundle pacing (HBP) or left bundle branch area pacing (LBBAP) is a rapidly developing field. These pacing techniques result in single lead left ventricular resynchronisation. Understanding of the associated learning curve of the two techniques is an important consideration for new implanters/implanting centres.

Left bundle branch area pacing in congenital heart disease.

Aims: Left bundle branch area pacing (LBBAP) has been shown to be effective and safe. Limited data are available on LBBAP in the congenital heart disease (CHD) population. This study aims to describe the feasibility and safety of LBBAP in CHD patients compared with non-CHD patients.

Precision Phenotyping of Dilated Cardiomyopathy Using Multidimensional Data.

Background: Dilated cardiomyopathy (DCM) is a final common manifestation of heterogenous etiologies. Adverse outcomes highlight the need for disease stratification beyond ejection fraction.

Objectives: The purpose of this study was to identify novel, reproducible subphenotypes of DCM using multiparametric data for improved patient stratification.

Moderate excess alcohol consumption and adverse cardiac remodelling in dilated cardiomyopathy.

Objective: The effect of moderate excess alcohol consumption is widely debated and has not been well defined in dilated cardiomyopathy (DCM). There is need for a greater evidence base to help advise patients. We sought to evaluate the effect of moderate excess alcohol consumption on cardiovascular structure, function and outcomes in DCM.

Internationally validated score to predict the outcome of non-paroxysmal atrial fibrillation ablation: the 'FLAME score'.

Background: The clinical effectiveness of ablating non-paroxysmal atrial fibrillation (non-PAF) relies on proper patient selection. We developed and validated a scoring system to predict non-PAF ablation outcomes.

Methods: Data on 416 non-PAF ablations were analysed using binary logistic regression at a London centre.

Resource use and clinical outcomes in patients with atrial fibrillation with ablation versus antiarrhythmic drug treatment.

Background: The objective of our study was to compare resource use and clinical outcomes among atrial fibrillation (AF) patients who underwent catheter ablation versus antiarrhythmic drug (AAD) treatment.

Methods: A retrospective cohort design using the Clinical Practice Research Data-Hospital Episode Statistics linkage data from England (2008-2013) was used. Patients undergoing catheter ablation treatment for AF were indexed to the date of first procedure.

Phenotype and Clinical Outcomes of Titin Cardiomyopathy.

Background: Improved understanding of dilated cardiomyopathy (DCM) due to titin truncation (TTNtv) may help guide patient stratification.

Objectives: The purpose of this study was to establish relationships among TTNtv genotype, cardiac phenotype, and outcomes in DCM.

Methods: In this prospective, observational cohort study, DCM patients underwent clinical evaluation, late gadolinium enhancement cardiovascular magnetic resonance, TTN sequencing, and adjudicated follow-up blinded to genotype for the primary composite endpoint of cardiovascular death, and major arrhythmic and major heart failure events.

Characterising the difference in electrophysiological substrate and outcomes between heart failure and non-heart failure patients with persistent atrial fibrillation.

Aims: Characterizing the differences in substrate and clinical outcome between heart failure (HF) and non-heart failure (non-HF) patients undergoing persistent atrial fibrillation (AF) ablation.

Methods And Results: Using complex fractionated electrograms (CFE) as a surrogate marker of substrate complexity, we compared the bi-atrial substrate in patients with persistent AF with and without HF, at baseline and after ablation, to determine its impact on clinical outcome. In this retrospective analysis of two prospective studies, 60 patients underwent de-novo step-wise left atrial (LA) ablation, 30 with normal left ventricular ejection fraction (LVEF) ≥ 50% (non-HF group) and 30 with LVEF ≤ 35% (HF group).

Evaluation of a novel high-resolution mapping system for catheter ablation of ventricular arrhythmias.

Background: The mapping of ventricular arrhythmias in humans using a minibasket 64-electrode catheter paired with a novel automatic mapping system (Rhythmia) has not been evaluated.

Objective: The purpose of this study was to evaluate the safety and efficacy of mapping ventricular arrhythmias and clinical outcomes after ablation using this system.

Methods: Electroanatomic maps for ventricular arrhythmias were obtained during 20 consecutive procedures in 19 patients (12 with ventricular tachycardia [VT] and 2 with ventricular ectopy [VE]).

Predicting atrial fibrillation ablation outcome: The CAAP-AF score.

Background: Patients with a variety of clinical presentations undergo atrial fibrillation (AF) ablation. Long-term ablation success rates can vary considerably.

Objective: The purpose of this study was to develop a clinical scoring system to predict long-term freedom from AF after ablation.

Left Atrial Appendage Electrical Isolation and Concomitant Device Occlusion to Treat Persistent Atrial Fibrillation: A First-in-Human Safety, Feasibility, and Efficacy Study.

Background: Left atrial appendage (LAA) electric isolation is reported to improve persistent atrial fibrillation (AF) ablation outcomes. However, loss of LAA mechanical function may increase thromboembolic risk. Concomitant LAA electric isolation and occlusion as part of conventional AF ablation has never been tested in humans.

Outcomes and costs of left atrial appendage closure from randomized controlled trial and real-world experience relative to oral anticoagulation.

Aims: The aim of this study was to analyse randomized controlled study and real-world outcomes of patients with non-valvular atrial fibrillation (NVAF) undergoing left atrial appendage closure (LAAC) with the Watchman device and to compare costs with available antithrombotic therapies.

Methods And Results: Registry data of LAAC from two centres were prospectively collected from 110 patients with NVAF at risk of stroke, suitable and unsuitable for long-term anticoagulation (age 71.3 ± 9.

Brompton Harefield Infection Score (BHIS): development and validation of a stratification tool for predicting risk of surgical site infection after coronary artery bypass grafting.

Objective: Surgical site infection (SSI) following coronary artery bypass grafting (CABG) is a serious complication associated with significant morbidity and mortality. Despite the substantial impact of SSI there is lack of a specific risk stratification tool to predict this complication after CABG. This study was undertaken to develop a specific prognostic scoring system for the development of SSI that could risk-stratify patients undergoing CABG.

Relationship between contact force sensing technology and medium-term outcome of atrial fibrillation ablation: a multicenter study of 600 patients.

Introduction: Contact force sensing (CFS) technology improves acute pulmonary vein isolation durability; however, its impact on the clinical outcome of ablating atrial fibrillation (AF) is unknown.

Methods And Results: First time AF ablation procedures employing CFS from 4 centers were matched retrospectively to those without CFS in a 1:2 manner by type of AF. Freedom from atrial tachyarrhythmia was defined as the primary outcome measure, and fluoroscopy time the secondary outcome measure.

Organizational index mapping to identify focal sources during persistent atrial fibrillation.

Introduction: Localized rotors have been implicated in the mechanism of persistent atrial fibrillation (AF). Although regions of highest dominant frequency (DF) on spectral analysis of the left atrium (LA) have been said to identify rotors, other mechanisms such as wavefront collisions will sporadically also generate an inconsistent distribution of high DF. We hypothesized that if drivers of AF were present, their distinctive spectral characteristics would result more from their temporal stability than their high frequency.

Adverse impact of chronic subpulmonary left ventricular pacing on systemic right ventricular function in patients with congenitally corrected transposition of the great arteries.

Background: Patients with congenitally corrected transposition of the great arteries (ccTGA) are at high risk of heart block requiring subpulmonary left ventricular (LV) pacing. Long-term right ventricular (RV) pacing in congenitally normal hearts is associated with LV dysfunction. We examined the effects of univentricular subpulmonary LV pacing on the systemic RV in a ccTGA cohort.

Outcomes of defibrillator therapy in catecholaminergic polymorphic ventricular tachycardia.

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia syndrome characterized by adrenergically induced ventricular arrhythmias in patients with structurally normal hearts. Initiating triggered arrhythmias, such as bidirectional ventricular tachycardia, often degenerate into reentrant arrhythmias, such as ventricular fibrillation (VF).

Objective: To determine whether the effectiveness of implantable cardioverter-defibrillator (ICD) shocks is dependent on rhythm type.

Impact of stepwise ablation on the biatrial substrate in patients with persistent atrial fibrillation and heart failure.

Background: Ablation of persistent atrial fibrillation can be challenging, often involving not only pulmonary vein isolation (PVI) but also additional linear lesions and ablation of complex fractionated electrograms (CFE). We examined the impact of stepwise ablation on a human model of advanced atrial substrate of persistent atrial fibrillation in heart failure.

Methods And Results: In 30 patients with persistent atrial fibrillation and left ventricular ejection fraction ≤35%, high-density CFE maps were recorded biatrially at baseline, in the left atrium (LA) after PVI and linear lesions (roof and mitral isthmus), and biatrially after LA CFE ablation.

United Kingdom national experience of entirely subcutaneous implantable cardioverter-defibrillator technology: important lessons to learn.

Aims: The aim of this study was to describe the early phase United Kingdom (UK) clinical experience with a novel entirely subcutaneous implantable cardioverter-defibrillator (S-ICD).

Methods And Results: A questionnaire was sent to all UK hospitals implanting S-ICDs. Nineteen of 25 (76%) hospitals responded with the details of 111 implanted patients [median 5/hospital (range 1-18)].

The safety and efficacy of trans-baffle puncture to enable catheter ablation of atrial tachycardias following the Mustard procedure: a single centre experience and literature review.

Background: Targets for catheter ablation of atrial tachyarrhythmias (AT) in post-Mustard procedure patients are often located in the pulmonary venous atrium (PVA). Traditional access to this chamber is retrograde via the aorta. However trans-baffle puncture may be a key determinant of successful ablation in many cases.