Distal Ventricular Pacing for Drug-Refractory Mid-Cavity Obstructive Hypertrophic Cardiomyopathy: A Randomized, Placebo-Controlled Trial of Personalized Pacing.

Background: Patients with refractory, symptomatic left ventricular (LV) mid-cavity obstructive (LVMCO) hypertrophic cardiomyopathy have few therapeutic options. Right ventricular pacing is associated with modest hemodynamic and symptomatic improvement, and LV pacing pilot data suggest therapeutic potential. We hypothesized that site-specific pacing would reduce LVMCO gradients and improve symptoms.

Near-field detection and peak frequency metric for substrate and activation mapping of ventricular tachycardias in two- and three-dimensional circuits.

Aims: Successful ventricular arrhythmia (VA) ablation requires identification of functionally critical sites during contact mapping. Estimation of the peak frequency (PF) component of the electrogram (EGM) may improve correct near-field (NF) annotation to identify circuit segments on the mapped surface. In turn, assessment of NF and far-field (FF) EGMs may delineate the three-dimensional path of a ventricular tachycardia (VT) circuit.

Feasibility of double-blinded, placebo-controlled interventional study for assessing catheter ablation efficacy in persistent atrial fibrillation: Insights from the ORBITA AF feasibility study.

Background: To date, there are no randomized, double-blinded clinical trials comparing catheter ablation to DC cardioversion (DCCV) with medical therapy in patients with persistent atrial fibrillation (PersAF). Conducting a large-scale trial to address this question presents considerable challenges, including recruitment, blinding, and implementation. We conducted a pilot study to evaluate the feasibility of conducting a definitive placebo-controlled trial.

Atrioventricular nodal ablation is an effective management strategy for atrial fibrillation in patients with hypertrophic cardiomyopathy.

Background: Atrial fibrillation (AF) is common in patients with hypertrophic cardiomyopathy (HCM) and can be challenging to manage. Atrioventricular nodal (AVN) ablation may be an effective management strategy for AF in these patients.

Objective: The purpose of this study was to assess the efficacy of AVN ablation in HCM patients who have failed medical therapy and/or catheter ablation for AF.

Exploiting SMART pass filter deactivation detection to minimize inappropriate subcutaneous implantable cardioverter defibrillator therapies: a real-world single-centre experience and management guide.

Aims: The SMART Pass™ (SP) algorithm is a high-pass filter that aims to reduce inappropriate therapy (IT) in subcutaneous internal cardiac defibrillator (S-ICD), but SP can deactivate due to low amplitude sensed R waves or asystole. The association between IT and SP deactivation and management strategies were evaluated, hypothesizing SP deactivation increases the risk of IT and device re-programming, or lead/generator re-positioning could reduce this risk.

Methods And Results: Retrospective single-centre audit of Emblem™ S-ICD devices implanted 2016 to 2020 utilizing health records and remote monitoring data.

Therapeutic benefits of distal ventricular pacing in mid-cavity obstructive hypertrophic cardiomyopathy.

Introduction: Hypertrophic cardiomyopathy (HCM) patients with left ventricular (LV) mid-cavity obstruction (LVMCO) often experience severe drug-refractory symptoms thought to be related to intraventricular obstruction. We tested whether ventricular pacing, guided by invasive haemodynamic assessment, reduced LVMCO and improved refractory symptoms.

Methods: Between December 2008 and December 2017, 16 HCM patients with severe refractory symptoms and LVMCO underwent device implantation with haemodynamic pacing study to assess the effect on invasively defined LVMCO gradients.

PolarX Cryoballoon metrics predicting successful pulmonary vein isolation: targets for ablation of atrial fibrillation.

Aim: Evaluate the novel PolarX Cryoballoon in atrial fibrillation (AF) catheter ablation through a propensity-matched comparison with the Arctic Front Advance (AFA). The aim was also to identify cryoablation metrics that are predictive of successful pulmonary vein isolation (PVI) with the PolarX Cryoballoon.

Methods And Results: This prospective multi-centre study included patients that underwent cryoablation for AF.

Transseptal puncture for left atrial ablation: Risk factors for cardiac tamponade and a proposed causative classification system.

Aims: Cardiac tamponade is a high morbidity complication of transseptal puncture (TSP). We examined the associations of TSP-related cardiac tamponade (TRCT) for all patients undergoing left atrial ablation at our center from 2016 to 2020.

Methods And Results: Patient and procedural variables were extracted retrospectively.

Detailed Assessment of Low-Voltage Zones Localization by Cardiac MRI in Patients With Implantable Devices.

Objectives: The purpose of this study was to assess the performance and limitations of low-voltage zones (LVZ) localization by optimized late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) scar imaging in patients with cardiac implantable electronic devices (CIEDs).

Background: Scar evaluation by LGE-CMR can assist ventricular tachycardia (VT) ablation, but challenges with electroanatomical maps coregistration and presence of imaging artefacts from CIED limit accuracy.

Methods: A total of 10 patients underwent VT ablation and preprocedural LGE-CMR using wideband imaging.

Ethanol ablation for ventricular arrhythmias: A systematic review and meta-analysis.

Introduction: Ethanol ablation (EA) is an alternative option for subjects with ventricular arrhythmias (VAs) refractory to conventional medical and ablative treatment. However, data on the efficacy and safety of EA remain sparse.

Methods: A systematic literature search was conducted.

Early pacemaker implantation for transcatheter aortic valve implantation is safe and effective.

Background: Permanent pacemaker (PPM) implantation is a common complication of transcatheter aortic valve implantation (TAVI). The optimum timing of PPM implantation is still unclear as conduction abnormalities evolve and a balance needs to be struck between conservative delays in the hope of conduction recovery and overutilization of pacing. This study aimed to assess the safety and efficacy of early PPM implantation, without an observation period, among TAVI patients.

Transvenous lead extraction on uninterrupted anticoagulation: A safe approach?

Introduction: Current guidelines advocate reviewing peri-procedural anticoagulation on individual case basis for transvenous lead extraction (TLE). We investigated the safety of TLE on uninterrupted warfarin with therapeutic INR.

Methods: Retrospective registry of consecutive patients undergoing TLE on uninterrupted warfarin (Warfarin Group) across two centres.

Catheter ablation of atrial fibrillation in patients with hypertrophic cardiomyopathy: a European observational multicentre study.

Aims: Atrial fibrillation (AF) is common in hypertrophic cardiomyopathy (HCM). Data on the efficacy of catheter ablation of AF in HCM patients are sparse.

Methods And Results: Observational multicentre study in 137 HCM patients (mean age 55.

A multi-center experience of ablation index for evaluating lesion delivery in typical atrial flutter.

Background: Anatomical studies demonstrate significant variation in cavotricuspid isthmus (CTI) architecture.

Methods: Thirty-eight patients underwent CTI ablation at two tertiary centers. Operators delivered 682 lesions with a target ablation index (AI) of 600 Wgs.

Initial experience of the High-Density Grid catheter in patients undergoing catheter ablation for atrial fibrillation.

Purpose: A significant proportion of patients undergoing catheter ablation for atrial fibrillation (AF) experience arrhythmia recurrence. This is mostly due to pulmonary vein reconnection (PVR). Whether mapping using High-Density Wave (HDW) technology is superior to standard bipolar (SB) configuration at detecting PVR is unknown.

Multicenter Study of Dynamic High-Density Functional Substrate Mapping Improves Identification of Substrate Targets for Ischemic Ventricular Tachycardia Ablation.

Objectives: The goal of this study was to evaluate the role of dynamic substrate changes in facilitating conduction delay and re-entry in ventricular tachycardia (VT) circuits.

Background: The presence of dynamic substrate changes facilitate functional block and re-entry in VT but are rarely studied as part of clinical VT mapping.

Methods: Thirty patients (age 67 ± 9 years; 27 male subjects) underwent ablation.

The Safety and Feasibility of Transitioning From Transfemoral to Transradial Access Left Ventricular Endomyocardial Biopsy.

Background: Left ventricular endomyocardial biopsy (LVEMB) is commonly performed via the transfemoral route. Radial access may help reduce vascular access complications, but there are few data on the safety and feasibility of transradial LVEMB.

Objective: Describe the safety and feasibility of transitioning from transfemoral to transradial access LVEMB.

Post-operative cardiac implantable electronic devices in patients undergoing cardiac surgery: a contemporary experience.

Aims: Optimum timing of pacemaker implantation following cardiac surgery is a clinical challenge. European and American guidelines recommend observation, to assess recovery of atrioventricular block (AVB) (up to 7 days) and sinus node (5 days to weeks) after cardiac surgery. This study aims to determine rates of cardiac implantable electronic devices (CIEDs) implants post-surgery at a high-volume tertiary centre over 3 years.

Percutaneous left ventricular endocardial leads: adverse outcomes and a percutaneous extraction case series.

Background: Conventional cardiac resynchronization therapy (CRT) involves the placement of an epicardial left ventricular (LV) lead through the coronary venous tree. However, alternative approaches of delivering CRT have been sought for patients who fail to respond to conventional methods or for those where coronary venous anatomy is unfavourable. Biventricular pacing through an endocardial LV lead has potential advantages; however, the long-term clinical and safety data are not known.