Pulsed field ablation in patients with complex consecutive atrial tachycardia in conjunction with ultra-high density mapping: Proof of concept.

Introduction: Catheter-ablation (CA) of consecutive left atrial tachycardias (LAT) can be challenging. Pulsed field ablation (PFA) yields a novel nonthermal CA technology for treatment of atrial fibrillation (AF). There is no data regarding PFA of LAT.

Characteristics and Prognostic Relevance of Ventricular Arrhythmia in Patients with Myocarditis.

Myocarditis is characterized by various clinical manifestations, with ventricular arrhythmia (VA) as a frequent symptom at initial presentation. Here, we investigated characteristics and prognostic relevance of VA in patients with myocarditis. The study population consisted of 76 patients with myocarditis, verified by biopsy and/or cardiac magnetic resonance (CMR) imaging, including 38 consecutive patients with VA (45 ± 3 years, 68% male) vs.

Pulsed-field ablation combined with ultrahigh-density mapping in patients undergoing catheter ablation for atrial fibrillation: Practical and electrophysiological considerations.

Background: Pulsed-field ablation (PFA) yields a novel ablation technology for atrial fibrillation (AF). PFA lesions promise to be highly durable, however clinical data on lesion characteristics are still limited.

Objective: This study sought to investigate PFA lesion creation with ultrahigh-density (UHDx) mapping.

Supervised Obesity Reduction Trial for AF ablation patients: results from the SORT-AF trial.

Aims: Weight management seems to be beneficial for obese atrial fibrillation (AF) patients; however, randomized data are sparse. Thus, this study aimed to investigate the influence of weight reduction on AF ablation outcomes.

Methods And Results: SORT-AF is an investigator-sponsored, prospective, randomized, multicentre, and clinical trial.

Specific electrogram characteristics impact substrate ablation target area in patients with scar-related ventricular tachycardia-insights from automated ultrahigh-density mapping.

Introduction: Substrate-based catheter ablation approaches to ventricular tachycardia (VT) focus on low-voltage areas and abnormal electrograms. However, specific electrogram characteristics in sinus rhythm are not clearly defined and can be subject to variable interpretation. We analyzed the potential ablation target size using automatic abnormal electrogram detection and studied findings during substrate mapping in the VT isthmus area.

Outcome after tailored catheter ablation of atrial tachycardia using ultra-high-density mapping.

Introduction: Tailored catheter ablation of atrial tachycardias (ATs) is increasingly recommended as a potentially easy treatment strategy in the era of high-density mapping (HDM). As follow-up data are sparse, we here report outcomes after HDM-guided ablation of ATs in patients with prior catheter ablation or cardiac surgery.

Methods And Results: In 250 consecutive patients (age 66.

Ultra-high-density mapping of conduction gaps and atrial tachycardias: Distinctive patterns following pulmonary vein isolation with cryoballoon or contact-force-guided radiofrequency current.

Introduction: The aim of this study was to investigate electrophysiological findings in patients with arrhythmia recurrence undergoing a repeat ablation procedure using ultra-high-density (UHDx) mapping following an index procedure using either contact-force (CF)-guided radiofrequency current (RFC) pulmonary vein isolation (PVI) or second-generation cryoballoon (CB) PVI for treatment of atrial fibrillation (AF).

Methods And Results: Fifty consecutive patients with recurrence of AF and/or atrial tachycardia (AT) following index CF-RFC PVI (n = 21) or CB PVI (n = 29) were included. A 64-pole mini-basket mapping catheter in combination with an UHDx-mapping system-guided ablation was used.

Advanced mapping strategies for ablation therapy in adults with congenital heart disease.

Background: Ultra-high density mapping (HDM) is a promising tool in the treatment of patients with complex arrhythmias. In adults with congenital heart disease (CHD), rhythm disorders are among the most common complications but catheter ablation can be challenging due to heterogenous anatomy and complex arrhythmogenic substrates. Here, we describe our initial experience using HDM in conjunction with novel automated annotation algorithms in patients with moderate to great CHD complexity.

Local impedance guides catheter ablation in patients with ventricular tachycardia.

Aims: Catheter contact and local tissue characteristics are relevant information for successful radiofrequency current (RFC)-ablation. Local impedance (LI) has been shown to reflect tissue characteristics and lesion formation during RFC-ablation. Using a novel ablation catheter incorporating three mini-electrodes, we investigated LI in relation to generator impedance (GI) in patients with ventricular tachycardia (VT) and its applicability as an indicator of effective RFC-ablation.

High-Density Mapping and Ablation of Primary Nonfocal Left Atrial Tachycardia: Characterizing a Distinct Arrhythmogenic Substrate.

Objectives: This study sought to characterize primary left atrial tachycardia (LAT) mechanisms, electrical properties and substrate using high-density mapping.

Background: Nonfocal LAT can be found in patients without prior substrate modifying interventions.

Methods: Of 223 catheter ablation procedures for LAT 15 patients (60% male, age 74 ± 6 years) had nonfocal AT and no history of LA ablation or cardiac surgery.

Respiratory sinus arrhythmia is reduced after pulmonary vein isolation in patients with paroxysmal atrial fibrillation.

Introduction: Respiratory sinus arrhythmia (RSA) describes heart rate (HR) changes in synchrony with respiration. It is relevant for exercise capacity and mechanistically linked with the cardiac autonomic nervous system. After pulmonary vein isolation (PVI), the current therapy of choice for patients with paroxysmal atrial fibrillation (AF), the cardiac vagal tone is often diminished.

A novel assessment of local impedance during catheter ablation: initial experience in humans comparing local and generator measurements.

Aims: A novel measure of local impedance (LI) has been found to predict lesion formation during radiofrequency current (RFC) catheter ablation. The aim of this study was to investigate the utility of this novel approach, while comparing LI to the well-established generator impedance (GI).

Methods And Results: In 25 consecutive patients with a history of atrial fibrillation, catheter ablation was guided by a 3D-mapping system measuring LI in addition to GI via an ablation catheter tip with three incorporated mini-electrodes.

5-Year Outcome of Pulmonary Vein Isolation by Loss of Pace Capture on the Ablation Line Versus Electrical Circumferential Pulmonary Vein Isolation.

Objectives: This study sought to compare long-term arrhythmia-free survival between electrical circumferential pulmonary vein isolation (PVI) and PVI with the endpoint of unexcitability along the ablation line.

Background: PVI is the standard ablation strategy of paroxysmal atrial fibrillation, although arrhythmia recurrence in long-term follow-up (FU) is high. The endpoint of unexcitability along the ablation line results in decreased arrhythmia recurrence compared to electrical PVI in 1-year FU.

Contact force facilitates the achievement of an unexcitable ablation line during pulmonary vein isolation.

Aims: Contact force (CF) catheters provide catheter-tissue contact information to improve outcome of pulmonary vein isolation (PVI) in paroxysmal atrial fibrillation (PAF). We evaluated different target-CF values for achievement of the additional endpoint of an unexcitable ablation line.

Methods: A total of 106 patients undergoing PVI were randomized into three groups (G) (G1: target-CF 15 g, G2: target-CF 10 g, G3: CF concealed from operator).

Incidence of intracardiac thrombus formation prior to electrical cardioversion in respect to the mode of oral anticoagulation.

Aims: To evaluate the incidence of newly diagnosed intracardiac thrombi (ICT) in respect to the mode of OAC in patients undergoing cardioversion (CV).

Methods And Results: We prospectively assessed transesophageal echocardiography (TEE) and OAC therapy prior to CV in AF patients with ≥48-hour duration scheduled for CV. A total of 60 first-time ICT (4.

Acute and long-term effects of fingolimod on heart rhythm and heart rate variability in patients with multiple sclerosis.

Background: Fingolimod can lead to increased risk of cardiac events such as bradycardia or atrioventricular (AV) block.

Objective: Evaluate acute and long-term effects of fingolimod on heart rhythm (HR), heart rate variability (HRV) and development of AV-blocks.

Methods: In 64 patients with relapsing-remitting multiple sclerosis Holter ECG monitoring (HEM) and HRV analysis were performed 24h before, six h during and 72h after initiation of fingolimod.

Risk stratification of patients with left atrial appendage thrombus prior to catheter ablation of atrial fibrillation: An approach towards an individualized use of transesophageal echocardiography.

Introduction: The need for transesophageal echocardiography (TEE) before catheter ablation of atrial fibrillation (CA-AF) is still being questioned. The aim of this study is to analyze patients' (patients) risk factors of left atrial appendage thrombus (LAAT) prior to CA-AF in daily clinical practice, according to oral anticoagulation (OAC) strategies recommended by current guidelines.

Methods And Results: All patients scheduled for CA-AF from 01/2015 to 12/2016 in our center were included and either treated with NOACs (novel-OAC; paused 24-hours preablation) or continuous vitamin K antagonists (INR 2.

Substrate characterization and catheter ablation in patients with scar-related ventricular tachycardia using ultra high-density 3-D mapping.

Background: Ablation of scar-related ventricular tachycardia (VT), especially in noninducible VT or hemodynamically unstable patients, can be challenging. Thus, we evaluated feasibility of an ultra high-density 3-D mapping approach to characterize the ventricular substrate and, if possible, to map VT.

Methods And Results: Twenty-two patients (67 ± 2 years, mean LV-EF 36 ± 3%) with both ischemic and nonischemic cardiomyopathy and documented VT underwent mapping and catheter ablation using a 64-electrode mini-basket catheter.

Catheter ablation of hemodynamically unstable ventricular tachycardia in ischemic cardiomyopathy using high-resolution mapping.

Catheter ablation is a recommended therapy option for ventricular tachycardia (VT). The antegrade transseptal approach for targeting VT with left ventricular origin is feasible with the high-resolution basket catheter. High-resolution mapping offers the potential to quickly acquire detailed voltage and activation maps.

Image integration into 3-dimensional-electro-anatomical mapping system facilitates safe ablation of ventricular arrhythmias originating from the aortic root and its vicinity.

Aims: During ablation in the vicinity of the coronary arteries establishing a safe distance from the catheter tip to the relevant vessels is mandatory and usually assessed by fluoroscopy alone. The aim of the study was to investigate the feasibility of an image integration module (IIM) for continuous monitoring of the distance of the ablation catheter tip to the main coronary arteries during ablation of ventricular arrhythmias (VA) originating in the sinus of valsalva (SOV) and the left ventricular summit part of which can be reached via the great cardiac vein (GCV).

Methods And Results: Of 129 patients undergoing mapping for outflow tract arrhythmias from June 2014 till October 2015, a total of 39 patients (52.

Local Electrical Dyssynchrony during Atrial Fibrillation: Theoretical Considerations and Initial Catheter Ablation Results.

Background: Electrogram-based identification of the regions maintaining persistent Atrial Fibrillation (AF) is a subject of ongoing debate. Here, we explore the concept of local electrical dyssynchrony to identify AF drivers.

Methods And Results: Local electrical dyssynchrony was calculated using mean phase coherence.

Influence of energy source on early atrial fibrillation recurrences: a comparison of cryoballoon vs. radiofrequency current energy ablation with the endpoint of unexcitability in pulmonary vein isolation.

Introduction: Comparative data of early recurrence rates of atrial fibrillation (ERAF) following second-generation cryoballoon (CB-G2) and radiofrequency current (RFC) ablation for pulmonary vein isolation (PVI) in paroxysmal AF (PAF) are rare. We randomized PAF patients into either PVI with CB-G2 (group 1) or PVI with a combined RFC-approach applying contact force (CF) with the endpoint of unexcitability (group 2) to investigate ERAF.

Methods And Results: In group 1 (n = 30), CB-G2-PVI was performed.

Characterization, Mapping, and Ablation of Complex Atrial Tachycardia: Initial Experience With a Novel Method of Ultra High-Density 3D Mapping.

Introduction: Conventional mapping of complex atrial tachycardias (ATs) can be challenging. Thus, we evaluated feasibility and utility of a novel, ultra high-density 3D mapping approach to characterize and map AT in these cases.

Methods And Results: Overall, 21 patients (67.

Loss of Pace Capture on the Ablation Line During Pulmonary Vein Isolation versus "Dormant Conduction": Is Adenosine Expendable?

Introduction: Permanent pulmonary vein isolation (PVI) remains an essential goal of ablation therapy in patients with atrial fibrillation. Aim of this study was the intraindividual comparison of unexcitability to pacing along the ablation line versus dormant conduction (DC) as additional procedural endpoints.

Methods: A total of 58 patients with paroxysmal atrial fibrillation (PAF) underwent PVI by circumferential ablation of ipsilateral pulmonary veins (PVs), followed by testing for DC by adenosine administration.