Atrial fibrillation cryoablation is an effective day case treatment: the UK PolarX vs. Arctic Front Advance experience.

Aims: Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation for atrial fibrillation (AF). There are limited data on the PolarX Cryoballoon. The study aimed to establish the safety, efficacy, and feasibility of same day discharge for Cryoballoon PVI.

Real-world evaluation of followup strategies after ICD therapies in patients with VT (REFINE-VT).

Implantable cardiac defibrillators (ICDs) can prevent sudden cardiac death, but the risk of recurrent ventricular arrhythmia (VA) and ICD shocks persist. Strategies to minimise such risks include medication optimisation, device programming and ventricular tachycardia (VT) ablation. Whether the choice of these interventions at follow-up are influenced by factors such as the type of arrhythmia or ICD therapy remains unclear.

Protocol update for a randomised controlled feasibility trial of exercise rehabilitation for people with postural tachycardia syndrome: the PULSE study.

Background: The PULSE (PostUraL tachycardia Syndrome Exercise) study is a randomised controlled trial assessing the feasibility of conducting a multicentre RCT testing supervised exercise rehabilitation with behavioural and motivational support, compared to best-practice usual care, for people with Postural Tachycardia Syndrome (PoTS). The original trial protocol was published in BMC Pilot & Feasibility Studies (accessible at https://doi.org/10.

Initial experience of temperature-controlled irrigated radiofrequency ablation for ischaemic cardiomyopathy ventricular tachycardia ablation.

Background: The DiamondTemp ablation (DTA) catheter system delivers high power, open-irrigated, temperature-controlled radiofrequency (RF) ablation. This novel ablation system has not been previously used for ventricular tachycardia (VT) ablation.

Objective: Feasibility of using the DTA catheter system for VT ablation in ischaemic cardiomyopathy (ICM) patients.

Safety and feasibility of trans-venous cardiac device extraction using conscious sedation alone-Implications for the post-COVID-19 era.

Background: Transvenous lead extraction (TLE) for implantable cardiac-devices is traditionally performed under general anesthesia (GA). This can lead to greater risk of exposure to COVID-19, longer recovery-times and increased procedural-costs. We report the feasibility/safety of TLE using conscious-sedation alone with immediate GA/cardiac-surgery back-up if needed.

Safety and outcome of nurse-led syncope clinics and implantable loop recorder implants.

Background: Implantable loop recorders (ILRs) are effective in achieving symptom-rhythm correlation. Data on the diagnostic yield of ILRs, on nurse-led syncope clinics, and on nurse-led ILR implants are limited.

Objective: We evaluated the safety and efficacy of our nurse-led syncope clinic and nurse-led ILR implants.

Case report: Managing profound circulatory collapse post-atrial fibrillation ablation: a methodical approach.

Background: Circulatory collapse during/post-pulmonary vein (PV) isolation by cryo-balloon ablation is a Cardiology emergency that has multiple potential causes and requires a methodical investigative approach. Some of the complications that can arise include cardiac tamponade, bleeding/vascular injury, anaphylaxis, Addisonian crisis, acute pulmonary embolism, acute PV stenosis, oesophageal injury, and vagal reaction.

Case Summary: Here, we present a case of a 76-year-old lady who developed profound circulatory collapse during an elective pulmonary vein isolation by cryo-balloon ablation for symptomatic paroxysmal atrial fibrillation (AF).

Impact of a high-density grid catheter on long-term outcomes for structural heart disease ventricular tachycardia ablation.

Background: Substrate mapping has highlighted the importance of targeting diastolic conduction channels and late potentials during ventricular tachycardia (VT) ablation. State-of-the-art multipolar mapping catheters have enhanced mapping capabilities. The purpose of this study was to investigate whether long-term outcomes were improved with the use of a HD Grid mapping catheter combining complementary mapping strategies in patients with structural heart disease VT.

Spectral characterization and impact of stepwise ablation protocol including LAA electrical isolation on persistent AF.

Objectives: To study how left atrial appendage electrical isolation (LAAEI) impacts atrial dominant frequency (DF) in patients with long-standing persistent atrial fibrillation (LSPAF).

Background: LAAEI is associated with a high probability of freedom from atrial fibrillation (AF) and spectral analysis may identify high-frequency sources. How LAAEI impacts the AF dynamics and the subgroup of LSPAF patients in whom LAAEI would be most beneficial, is unclear.

Protocol for a randomised controlled feasibility trial of exercise rehabilitation for people with postural tachycardia syndrome: the PULSE study.

Background: Postural orthostatic tachycardia syndrome (POTS) is an autonomic nervous system disorder causing an abnormal cardiovascular response to upright posture. It affects around 0.2% of the population, most commonly women aged 13 to 50 years.

Safety and cost-effectiveness of same-day complex left atrial ablation.

Background: Catheter ablation for complex left-atrial arrhythmia is increasing worldwide with many centres admitting patients overnight. Same-day procedures using conscious sedation carry significant benefits to patients/healthcare providers but data are limited. We evaluated the safety and cost-effectiveness of same-day complex left-atrial arrhythmia ablation.

Long-term follow-up of normal and structural heart ventricular tachycardia catheter ablation: real-world experience from a UK tertiary centre.

Background: Ventricular tachycardia (VT) is associated with increased morbidity and mortality. There is growing evidence for the effectiveness of catheter ablation in improving outcomes in patients with recurrent VT. Consequently the threshold for referral for VT ablation has fallen over recent years, resulting in increased number of procedures.

Enhanced ventricular tachycardia substrate resolution with a novel omnipolar high-density mapping catheter: the omnimapping study.

Background: Defining diastolic slow-conduction channels within the borderzone (BZ) of scar-dependent re-entrant ventricular tachycardia (VT) is key for effective mapping and ablation strategies. Understanding wavefront propagation is driving advances in high-density (HD) mapping. The newly developed Advisor™ HD Grid Mapping Catheter (HD GRID) has equidistant spacing of 16, 1 mm electrodes in a 4 × 4 3 mm interspaced arrangement allowing bipolar recordings along and uniquely across the splines (orthogonal vector) to facilitate substrate mapping in a WAVE configuration (WAVE).

Characterization of the Mechanism and Substrate of Atrial Tachycardia Using Ultra-High-Density Mapping in Adults With Congenital Heart Disease: Impact on Clinical Outcomes.

Background Atrial tachycardia ( AT ) is common in patients with adult congenital heart disease and is challenging to map and ablate. We used ultra-high-density mapping to characterize the AT mechanism and investigate whether substrate characteristics are related to ablation outcomes. Methods and Results A total of 50 AT s were mapped with ultra-high-density mapping in 23 procedures.

Ventricular tachycardia ablation in structural heart disease: Impact of ablation strategy and non-inducibility as an end-point on long term outcome.

Background: To investigate the long term outcomes after catheter ablation (CA) of ventricular tachycardia (VT) in the context of structural heart disease in a multicenter cohort. The impact of different ablation strategies (substrate ablation versus activation guided versus combined) and non-inducibility as an end-point was evaluated.

Methods: Data was pooled from prospective registries at 5 centres over a 5 year period.

Catheter ablation vs electrophysiologically guided thoracoscopic surgical ablation in long-standing persistent atrial fibrillation: The CASA-AF Study.

Background: Catheter ablation (CA) outcomes for long-standing persistent atrial fibrillation (LSPAF) remain suboptimal. Thoracoscopic surgical ablation (SA) provides an alternative approach in this difficult to treat cohort.

Objective: To compare electrophysiological (EP) guided thoracoscopic SA with percutaneous CA as the first-line strategy in the treatment of LSPAF.

Cardiac CT assessment of tissue thickness at the ostium of the left atrial appendage predicts acute success of radiofrequency ablation.

Background: Tissue thickness at the site of ablation is a determinant of lesion transmurality. We reported the feasibility, safety, and efficacy of longstanding persistent atrial fibrillation ablation, incorporating deliberate left atrial appendage (LAA) isolation and occlusion, and identified systematic differences in ostial LAA tissue thickness in a matched cohort of cadaveric specimens.

Methods: Preprocedural cardiac computed tomography (CCT) scans were acquired from 22 patients undergoing LAA isolation and subsequent occlusion.

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]).

Percutaneous left atrial appendage occlusion using different technologies in the United Kingdom: A multicenter registry.

Objectives: This study aimed at assessing the feasibility and long-term efficacy of left atrial appendage occlusion (LAAO) in a "real world" setting.

Background: Although LAAO has recently emerged as an alternative to oral anticoagulants in patients with atrial fibrillation for the prevention of thromboembolic stroke, "real world" data about the procedure with different devices are lacking.

Methods: Eight centers in the United Kingdom contributed to a retrospective registry for LAAO procedures undertaken between July 2009 and November 2014.

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.