Predictors of recurrence of atrial fibrillation within the first 3 months after ablation.

Aims: Freedom from atrial fibrillation (AF) at 1 year can be achieved in 50-70% of patients undergoing catheter ablation. Recurrent AF early after ablation most commonly terminates spontaneously without further interventional treatment but is associated with later recurrent AF. The aim of this investigation is to identify clinical and procedural factors associated with recurrence of AF early after ablation.

A simple method to detect leaks after left atrial appendage occlusion with Watchman.

Background: We evaluated the efficacy of a new method in identifying peri-device leak (PDL) using morphology of the thrombus formed inside the left atrial appendage (LAA) as seen on follow-up transesophageal echo (TEE).

Method: A total of 291 consecutive patients undergoing Watchman procedure were included in this analysis. TEE was performed at 45 days postprocedure.

Outcomes of junctional ectopic tachycardia ablation in adult population-a multicenter experience.

Purpose: Idiopathic junctional ectopic tachycardia (JET) is typically refractory to antiarrhythmic agents. Catheter ablation for JET is feasible but is associated with high risk of unintended atrioventricular (AV) block. There is limited data on the appropriate procedural technique and clinical outcomes with catheter ablation for idiopathic JET in adults.

Exclusion of electrical and mechanical function of the left atrial appendage in patients with persistent atrial fibrillation: differences in efficacy and safety between endocardial ablation vs epicardial LARIAT ligation (the EXCLUDE LAA study).

Background: Electrical isolation of the left atrial appendage (LAA) may provide incremental benefits for arrhythmia management in patients undergoing radiofrequency ablation (RFA) for persistent atrial fibrillation (AF).

Objective: The aim of this study was to compare efficacy and safety of endocardial ablation and LAA exclusion with LARIAT device for electrical and mechanical exclusion of LAA.

Methods: We compared patients who underwent endocardial LAA isolation during index RFA for persistent AF and underwent a repeat RFA to patients who underwent LAA exclusion with LARIAT device followed by RFA for AF in this multicenter registry.

WATCHMAN implantation in patients with a history of atrial fibrillation and intracranial hemorrhage.

Purpose: Use of oral anticoagulation (OAC) in patients with a history of intracranial hemorrhage (ICH) is often considered high risk as OAC-related ICH is associated with high mortality rates. Left atrial appendage closure with a WATCHMAN device is an alternative management strategy to OAC to decrease thrombotic risk in atrial fibrillation patients; however use of OAC followed by dual antiplatelet therapy (DAPT) or DAPT therapy alone is required for 6 months post-procedurally. In this study, we examined the safety of WATCHMAN implantation followed by 6 months of anti-thrombotic therapy in patients with a history of ICH.

Simple electrocardiographic criteria for rapid identification of wide QRS complex tachycardia: The new limb lead algorithm.

Background: The electrocardiogram (ECG) is essential for the differential diagnosis of wide QRS complex tachycardia (WCT).

Objective: The purpose of this study was to evaluate the diagnostic value of a novel ECG algorithm on the basis of the morphological characteristics of the QRS on the limb leads.

Methods: The limb lead algorithm (LLA) was evaluated by analyzing 528 monomorphic WCTs with electrophysiology-confirmed diagnoses.

Association of fragmented QRS with left atrial scarring in patients with persistent atrial fibrillation undergoing radiofrequency catheter ablation.

Background: Fragmented QRS (fQRS) on 12-lead electrocardiography is a noninvasive marker of intramyocardial conduction delay due to ventricular scarring that has not previously been studied in atrial fibrillation.

Objective: The purpose of this study was to assess the association of fQRS with left atrial (LA) scarring in patients with persistent atrial fibrillation (PsAF) undergoing first catheter ablation.

Methods: A total of 376 patients with PsAF were enrolled.

Stroke Risk in Patients With Atrial Fibrillation Undergoing Electrical Isolation of the Left Atrial Appendage.

Background: Loss of contractility leading to stasis of blood flow following left atrial appendage electrical isolation (LAAEI) could lead to thrombus formation.

Objectives: This study evaluated the incidence of thromboembolic events (TE) in post-LAAEI cases "on" and "off" oral anticoagulation (OAC).

Methods: A total of 1,854 consecutive post-LAAEI patients with follow-up transesophageal echocardiography (TEE) performed in sinus rhythm at 6 months to assess left atrial appendage (LAA) function were included in this analysis.

Closure of foramen ovale triggered by injury to tunnel surfaces of septum primum and secundum.

Introduction: We investigated the feasibility to proactively stimulate subsequent closure of a patent foramen ovale (PFO) by injuring (mechanical trauma or radiofrequency [RF] energy) the opposing surfaces of the septum primum (SP) and septum secundum (SS).

Methods: 1. Mechanical Injury: The interatrial septum of patients who underwent multiple left atrial (LA) ablations over 6 years, where a PFO was used for LA access, were examined.

Impact of dense "smoke" detected on transesophageal echocardiography on stroke risk in patients with atrial fibrillation undergoing catheter ablation.

Background: Spontaneous echocardiographic contrast ("smoke") within the left atrial cavity on transesophageal echocardiography (TEE) suggests low blood flow velocities in the heart that may lead to thromboembolic (TE) events.

Objective: The purpose of this study was to evaluate the risk of TE events in the periprocedural period and at long-term follow-up in atrial fibrillation (AF) patients having dense smoke on preprocedural TEE.

Methods: A total of 2511 patients undergoing AF ablation were included in this analysis.

Outcomes of Catheter Ablation of Ventricular Tachycardia Based on Etiology in Nonischemic Heart Disease: An International Ventricular Tachycardia Ablation Center Collaborative Study.

Objectives: This study sought to characterize ventricular tachycardia (VT) ablation outcomes across nonischemic cardiomyopathy (NICM) etiologies and adjust these outcomes by patient-related comorbidities that could explain differences in arrhythmia recurrence rates.

Background: Outcomes of catheter ablation of VT in patients with NICM could be related to etiology of NICM.

Methods: Data from 2,075 patients with structural heart disease referred for catheter ablation of VT from 12 international centers was retrospectively analyzed.

Hemodynamic Support in Ventricular Tachycardia Ablation: An International VT Ablation Center Collaborative Group Study.

Objectives: This study sought to evaluate the clinical outcomes of patients receiving hemodynamic support (HS) during ventricular tacchycardia (VT) ablation.

Background: There are limited real-world data evaluating its effect of HS in ablation outcomes.

Methods: An analysis of 1,655 patients from the International VT Ablation Center Collaborative group was performed.

Atrial Tachycardias After Surgical Atrial Fibrillation Ablation: Clinical Characteristics, Electrophysiological Mechanisms, and Ablation Outcomes From a Large, Multicenter Study.

Objectives: The clinical characteristics, electrophysiological mechanisms, and ablation outcomes of post-surgical atrial fibrillation ablation (SAFA) atrial tachycardias (ATs) have not been studied in a large, multicenter cohort.

Background: ATs are often seen following SAFA.

Methods: Analysis was performed on 137 patients (age, 62 ± 10 years; 74% male) who underwent catheter ablation for symptomatic post-SAFA AT from 2004 to 2013 at 3 high-volume institutions in the United States.

Feasibility, safety, and efficacy of a novel preshaped nitinol esophageal deviator to successfully deflect the esophagus and ablate left atrium without esophageal temperature rise during atrial fibrillation ablation: The DEFLECT GUT study.

Background: Esophageal thermal injury is a feared complication of radiofrequency ablation for atrial fibrillation (AF). Rise in luminal esophageal temperature (LET) limits the ability to deliver radiofrequency energy on the posterior wall of the left atrium.

Objective: The purpose of this study was to evaluate the feasibility, safety, and efficacy of a mechanical esophageal deviation (ED) tool during AF ablation.

Impact of weight loss on ablation outcome in obese patients with longstanding persistent atrial fibrillation.

Aims: This study investigated the impact of weight loss in longstanding persistent (LSPAF) patients undergoing catheter ablation (CA).

Methods: Ninety consecutive obese LSPAF patients were approached; 58 volunteered to try weight loss interventions for up to 1 year (group 1), while 32 patients declined weight loss interventions and were included as a control (group 2). Both groups remained on antiarrhythmic drugs.

Procedural findings and ablation outcome in patients with atrial fibrillation referred after two or more failed catheter ablations.

Introduction: This study reports the procedural findings and ablation outcome in AF patients referred after ≥2 failed PV isolation (PVI).

Methods: Three hundred and five consecutive AF patients referred after ≥2 PVI were included in the analysis. High-dose isoproterenol challenge was used to identify PV reconnection and non-PV triggers; the latter were ablated based on the operator's discretion during the index procedure.

Electroanatomical mapping systems and intracardiac echo integration for guided endomyocardial biopsy.

During the past years, endomyocardial biopsy (EMB) has gradually spread into clinical practice. However, the role of EMB in the diagnosis and treatment of cardiovascular diseases remains a controversial issue, especially in the setting of unexplained ventricular arrhythmias. Areas covered: This review describes the methodology of EMB guided by combined use of three-dimensional electroanatomical mapping systems and intracardiac echo and summarizes the classical, fluoroscopy-guided EMB technique.

Early Mortality After Catheter Ablation of Ventricular Tachycardia in Patients With Structural Heart Disease.

Background: In patients referred for radiofrequency catheter ablation (RFCA) of ventricular tachycardia (VT) in the setting of structural heart disease, early post-procedural mortality (EM) has not been previously investigated.

Objectives: The purpose of this study was to evaluate EM after catheter ablation of scar-related VT.

Methods: Associations between clinical and procedural variables and EM (within 31 days of the procedure) were tested in patients with structural heart disease undergoing RFCA of VT at 12 international centers.

Prevalence of right atrial non-pulmonary vein triggers in atrial fibrillation patients treated with thyroid hormone replacement therapy.

Background: Thyroid hormone (TH) is known to enhance arrhythmogenicity, and high-normal thyroid function is related with an increased recurrence of atrial fibrillation (AF) after catheter ablation. However, the impact of thyroid hormone replacement (THR) on AF ablation is not well known.

Methods: This study evaluated 1163 consecutive paroxysmal AF patients [160 (14%) on THR and 1003 (86%) without THR] undergoing their first catheter ablation.

Multipoint pacing via a quadripolar left-ventricular lead: preliminary results from the Italian registry on multipoint left-ventricular pacing in cardiac resynchronization therapy (IRON-MPP).

Aims: This registry was created to describe the experience of 76 Italian centres with a large cohort of recipients of multipoint pacing (MPP) capable cardiac resynchronization therapy (CRT) devices.

Methods And Results: A total of 507 patients in whom these devices had been successfully implanted were enrolled between August 2013 and May 2015. We analysed: (i) current clinical practices for the management of such patients, and (ii) the impact of MPP on heart failure clinical composite response and on the absolute change in ejection fraction (EF) at 6 months.

Is transesophageal echocardiogram mandatory in patients undergoing ablation of atrial fibrillation with uninterrupted novel oral anticoagulants? Results from a prospective multicenter registry.

Background: Transesophageal echocardiography (TEE) is recommended in patients undergoing atrial fibrillation (AF) ablation, but use of this strategy is variable.

Objective: To evaluate whether TEE is necessary before AF ablation in patients treated with novel oral anticoagulants (NOACs).

Methods: We performed a prospective multicenter registry of AF patients undergoing radiofrequency catheter ablation on uninterrupted NOACs (apixaban and rivaroxaban).