Dielectric response as a novel marker for ablation lesion quality: Relation to conventional ablation parameters.

Background: The tissue response viewer (TRV) is a novel marker for ablation lesion quality that aims to classify lesions into transmural or nontransmural lesions (high or low dielectric response, HDR or LDR) using dielectric-based tissue assessment. The objective of this study was to gain insight in the TRV by relating its outcomes to conventional ablation parameters.

Methods: Patients that had repeat ablation for atrial fibrillation with a dielectric imaging-based mapping system were enrolled.

High-density mapping for ablation of atypical atrial flutters - procedural characteristics related to outcome.

Background: High-density (HD) mapping is increasingly used to characterize arrhythmic substrate for ablation of atypical atrial flutters (AAFl). However, results on clinical outcomes and factors that are associated with arrhythmia recurrence are scarce.

Methods: Single-center, prospective, observational cohort study that enrolled patients with catheter ablation for AAFl using a HD mapping system and a grid-shaped mapping catheter.

Long-term success of a multi-electrode substrate mapping and ablation strategy versus a classic single tip mapping and ablation strategy for ventricular tachycardia ablation in patients with ischemic cardiomyopathy.

Introduction: Over the past years, mapping and ablation techniques for the treatment of ventricular tachycardia (VT) have evolved rapidly. High Density (HD) substrate mapping is now routine and pre-procedural imaging is increasingly used. The additional value of these techniques for long-term VT-free survival is not clear.

Efficacy and safety of the GOLD FORCE multicentre randomized clinical trial: multielectrode phased radiofrequency vs. irrigated radiofrequency single-tip catheter with contact force ablation for treatment of symptomatic paroxysmal atrial fibrillation.

Aims: Pulmonary vein isolation (PVI) for atrial fibrillation (AF) has become increasingly safe and effective with the evolution of single-tip ablation catheters aided by contact force sensing (ST-CF) and single-shot devices such as the second-generation pulmonary vein ablation catheter (PVAC) Gold multi-electrode array. The multicentre randomized GOLD FORCE trial was conducted to evaluate non-inferiority of safety and efficacy of PVAC Gold PVI compared to ST-CF ablation for paroxysmal AF.

Methods And Results: The primary efficacy endpoint documented AF recurrence ≥30 s was assessed by time-to-first-event analysis after a 90-day blanking period using repeated 7-day Holters.

Dielectric imaging for electrophysiology procedures: The technology, current state, and future potential.

Electroanatomic mapping systems have become an essential tool to guide the identification and ablation of arrhythmic substrate. Recently, a novel guiding system for electrophysiology procedures was introduced that uses dielectric sensing to perform high resolution anatomical imaging. Dielectric imaging systems use electrical fields to differentiate anatomic structures based on their conductivity and permittivity.

ICD implantation for secondary prevention in patients with ventricular arrhythmia in the setting of acute cardiac ischemia and a history of myocardial infarction.

Introduction: In patients with a prior myocardial infarction (MI) but preserved left ventricular (LV) function, sustained ventricular arrhythmias (VAs) may arise in the setting of an acute coronary syndrome (ACS). It is unknown whether an implantable cardioverter-defibrillator (ICD) is mandatory in these patients as VA might be triggered by a reversible cause. The purpose of this study is to analyze the benefit of ICD therapy in this patient population.

Sex differences in implantable cardiac defibrillator therapy according to arrhythmia detection times.

Objective: In implantable cardiac defibrillators (ICDs), long-detection times safely reduce unnecessary and inappropriate therapies. We aimed to evaluate ICD treatment of ventricular arrhythmias in women, compared with men, also taking into account ICD detection.

Methods: The Advance III trial randomised patients implanted with an ICD for primary or secondary prevention in two arms-long and nominal ventricular arrhythmias detection times before therapy delivering (number of intervals needed to detect (NID) 30/40 and 18/24, respectively).

Left atrial catheter ablation in patients with previously implanted left atrial appendage closure devices.

Aims: Left atrial appendage closure (LAAC) is increasingly used as an alternative to oral anticoagulation (OAC) for stroke prevention in atrial fibrillation (AF) patients. Feasibility and safety of left atrial (LA) catheter ablation (CA) in patients with previously implanted LAAC devices have not been well studied. We report on the feasibility, safety, and efficacy of LA CA in the presence of a previously implanted LAAC device.

External electrical cardioversion in patients with cardiac implantable electronic devices: Is it safe and is immediate device interrogation necessary?

Background: Atrial tachyarrhythmias are common in patients with cardiac implantable electronic devices (CIEDs). Restoration of sinus rhythm by external electrical cardioversion (eECV) is frequently used to alleviate symptoms and to ensure optimal device function.

Objectives: To evaluate the safety of eECV in patients with contemporary CIEDs and to assess the need for immediate device interrogation after eECV.

Long Detection Programming in Single-Chamber Defibrillators Reduces Unnecessary Therapies and Mortality: The ADVANCE III Trial.

Objectives: This study sought to evaluate the effects of programming a long detection in single-chamber (VVI) implantable cardioverter-defibrillators (ICDs) in the multicenter prospective ADVANCE III (Avoid DeliVering TherApies for Non-sustained Arrhythmias in ICD PatiEnts III) trial.

Background: Programming strategies may reduce unnecessary ICD shocks and their adverse effects but to date have been described only for dual-chamber ICDs.

Methods: A total of 545 subjects (85% male; atrial fibrillation 25%, left ventricular ejection fraction 31%, ischemic etiology 68%, secondary prevention indications 32%) receiving a VVI ICD were randomized to long detection (30 of 40 intervals) or standard programming (18 of 24 intervals) based on device type, atrial fibrillation history, and indication.

Effects of epicardial versus transvenous left ventricular lead placement on left ventricular function and cardiac perfusion in cardiac resynchronization therapy: A randomized clinical trial.

Introduction: Optimal left ventricular (LV) lead position in patients undergoing cardiac resynchronization therapy (CRT) is crucial to achieve an optimal effect on hemodynamics. Due to various difficulties, up to 30% of transvenous LV lead placements fail, or a suboptimal position is achieved. Surgical epicardial LV lead placement could be performed at a position anticipated to be the optimal site.

Different impact of long-detection interval and anti-tachycardia pacing in reducing unnecessary shocks: data from the ADVANCE III trial.

Aims: A long-detection interval (LDI) (30/40 intervals) has been proved to be superior to a standard-detection interval (SDI) (18/24 intervals) in terms of reducing unnecessary implantable cardioverter defibrillator (ICD) therapies. To better evaluate the different impact of LDI and anti-tachycardia pacing (ATP) on reducing painful shocks, we assessed all treated episodes in the ADVANCE III trial.

Methods And Results: A total of 452 fast (200 ms < cycle length ≤ 320 ms) arrhythmic episodes were recorded: 284 in 138 patients in the SDI arm and 168 in 82 patients in the LDI arm (106/452 inappropriate detections).

Multielectrode Pulmonary Vein Isolation Versus Single Tip Wide Area Catheter Ablation for Paroxysmal Atrial Fibrillation: A Multinational Multicenter Randomized Clinical Trial.

Background: Single-shot ablation techniques may facilitate safe and simple pulmonary vein isolation to treat paroxysmal atrial fibrillation. Multielectrode pulmonary vein isolation versus single tip wide area catheter ablation-paroxysmal atrial fibrillation is the first multinational, multicenter, prospective, noninferiority randomized clinical trial comparing multielectrode-phased radiofrequency ablation (MEA) to standard focal irrigated radiofrequency ablation (STA) using 3-dimensional navigation.

Methods And Results: Patients with paroxysmal atrial fibrillation were randomized to MEA (61 patients) or STA (59 patients).

Continuous rhythm monitoring for ventricular arrhythmias after alcohol septal ablation for hypertrophic cardiomyopathy.

Objective: The purpose of the present study was to determine the incidence of ventricular arrhythmias before and after alcohol septal ablation (ASA).

Background: In patients with hypertrophic obstructive cardiomyopathy (HOCM), gradient reduction by ASA is an alternative for surgical myectomy. However, concerns exist about whether the induction of a myocardial scar during ASA may create substrate for ventricular arrhythmias.

Efficacy of long detection interval implantable cardioverter-defibrillator settings in secondary prevention population: data from the Avoid Delivering Therapies for Nonsustained Arrhythmias in ICD Patients III (ADVANCE III) trial.

Background: Three trials demonstrated recently that a long detection window reduces implantable cardioverter-defibrillator (ICD) therapy in primary prevention patients. Avoid Delivering Therapies for Nonsustained Arrhythmias in ICD Patients III (ADVANCE III) was the only trial that enrolled both primary and secondary prevention patients.

Methods And Results: Of the 1902 patients enrolled in the ADVANCE III trial, 477 received a defibrillator for secondary prevention; 248 patients were randomly assigned to a long detection setting (30 of 40 intervals) and 229 to the nominal setting (18 of 24 intervals) for ventricular arrhythmias with cycle length ≤ 320 ms.

Safety of pulmonary vein isolation and left atrial complex fractionated atrial electrograms ablation for atrial fibrillation with phased radiofrequency energy and multi-electrode catheters.

Aims: Recently, a multi-electrode catheter system using phased radiofrequency (RF) energy was developed specifically for atrial fibrillation (AF) ablation: the pulmonary vein ablation catheter (PVAC), the multi-array septal catheter (MASC), and the multi-array ablation catheter (MAAC). Initial results of small trials have been promising: shorter procedure times and low adverse event rates. In a large single-centre registry, we evaluated the adverse events associated with multi-electrode ablation catheter procedures with PVAC alone, or combined with MASC and MAAC.

Freedom from paroxysmal atrial fibrillation after successful pulmonary vein isolation with pulmonary vein ablation catheter-phased radiofrequency energy: 2-year follow-up and predictors of failure.

Aims: In patients with paroxysmal atrial fibrillation (PAF) the pattern of atrial fibrillation (AF) episodes and the total AF burden, may be related to the efficacy of pulmonary vein isolation (PVI). We evaluated (pre)-procedural factors explaining the long-term outcome after PVI, using a ring-shaped multielectrode ablation catheter [pulmonary vein ablation catheter (PVAC)].

Methods And Results: A total of 120 consecutive patients with PAF were treated with the PVAC.

Atrial fibrillation catheter ablation versus surgical ablation treatment (FAST): a 2-center randomized clinical trial.

Background: Catheter ablation (CA) and minimally invasive surgical ablation (SA) have become accepted therapy for antiarrhythmic drug-refractory atrial fibrillation. This study describes the first randomized clinical trial comparing their efficacy and safety during a 12-month follow-up.

Methods And Results: One hundred twenty-four patients with antiarrhythmic drug-refractory atrial fibrillation with left atrial dilatation and hypertension (42 patients, 33%) or failed prior CA (82 patients, 67%) were randomized to CA (63 patients) or SA (61 patients).

Arrhythmia detection after atrial fibrillation ablation: value of incremental monitoring time.

Background: After pulmonary vein isolation (PVI), patients need to be followed to analyze the effect of the treatment. We evaluated the influence of the duration of Holter monitoring on the detection of arrhythmia recurrences after a single PVI at 12 months.

Methods: Consecutive patients with paroxysmal atrial fibrillation (AF) underwent successful PVI with phased radiofrequency and pulmonary vein ablation catheter.

Early recurrence of atrial fibrillation as a predictor for 1-year efficacy after successful phased RF pulmonary vein isolation: evaluation of complaints and multiple Holter recordings.

Background: Early arrhythmia recurrences after pulmonary vein isolation (PVI) for atrial fibrillation (AF) are accepted as part of the blanking period. Their relevance for long-term efficacy is not well-known. We evaluated patients, who came to hospital with a documented recurrence of AF, or had a registered episode of AF on the 24-hour Holter 6 weeks after PVI and compared it with long-term outcome.

Pulmonary vein anatomy and long-term outcome after multi-electrode pulmonary vein isolation with phased radiofrequency energy for paroxysmal atrial fibrillation.

Aims: We evaluated the effect of pulmonary vein (PV) anatomical characteristics on PV isolation (PVI) and long-term efficacy of ablation with phased radiofrequency (RF) energy and pulmonary vein ablation catheter (PVAC) multi-electrode catheter.

Methods And Results: Before the procedure, PV anatomy was visualized by magnetic resonance imaging (MRI). Consecutive patients with paroxysmal atrial fibrillation were treated with the PVAC with successful acute isolation.

Pulmonary vein isolation and left atrial complex-fractionated atrial electrograms ablation for persistent atrial fibrillation with phased radio frequency energy and multi-electrode catheters: efficacy and safety during 12 months follow-up.

Aims: Ablation for persistent atrial fibrillation (AF) remains a difficult and time-consuming procedure with varying degrees of success. We evaluated the long-term effects of a novel approach for ablation of persistent AF using multi-electrode catheters.

Methods And Results: In 89 patients with longstanding persistent AF (>1 year), multi-electrode ablation was performed with a pulmonary vein ablation catheter (PVAC), a multi-array septal catheter (MASC), and a multi-array ablation catheter (MAAC) for ablation of complex-fractionated atrial electrograms (CFAE) at the septum, left atrial (LA) roof, floor, posterior wall, and mitral isthmus.

Voltage analysis after multi-electrode ablation with duty-cycled bipolar and unipolar radiofrequency energy: a case report.

Pulmonary vein ablation with a single-tip catheter remains long and complex. We describe a typical case of a novel efficient technique with a decapolar ring catheter utilizing alternating unipolar/bipolar radiofrequency energy. Voltage analysis and electrical mapping demonstrate the potential for antrum ablation and pulmonary vein isolation.