Doreen Schreiber

Pulmonary Vein Isolation Versus Defragmentation: The CHASE-AF Clinical Trial.

BACKGROUND Long-term success rates using ablation for persistent atrial fibrillation (AF) are disappointing and usually do not exceed 60%. OBJECTIVES This study sought to compare arrhythmia-free survival between pulmonary vein isolation (PVI) and a stepwise approach (full defrag) consisting of PVI, ablation of complex fractionated electrograms, and additional linear ablation lines in the setting of atrial tachycardias (AT) in patients with persistent AF after PVI. METHODS From November 2010 to February 2013, 205 patients (151 men; 61.7 ± 10.2 years of age) underwent de novo ablation for persistent AF. Subsequently, patients were prospectively randomized to either PVI alone (n = 78) or full defrag (n = 75), with 52 patients not randomized due to AF termination with the original PVI. The primary endpoint was recurrence of any AT after a blanking period of 3 months. RESULTS During the entire study, 241 ablations were performed (mean: 1.59 in the PVI-alone group, 1.55 in the full-defrag group). With the stepwise approach, termination of AF occurred in 45 (60%) patients. However, arrhythmia-free survival did not differ whether patients underwent single or multiple procedures (p = 0.468). Procedure duration, fluoroscopy time, and radiofrequency duration were significantly longer in the full-defrag group (all p < 0.001). CONCLUSIONS A stepwise approach aimed at AF termination does not seem to provide additional benefit over PVI alone in patients with persistent AF, but it is associated with significantly longer procedural and fluoroscopic duration as well as radiofrequency application time. (The Randomized Catheter Ablation of Persist End Atrial Fibrillation Study [CHASE-AF]; NCT01580124).

Box Isolation of Fibrotic Areas (BIFA): A Patient-Tailored Substrate Modification Approach for Ablation of Atrial Fibrillation

Catheter ablation strategies beyond pulmonary vein isolation (PVI) for treatment of atrial fibrillation (AF) are less well defined. Increasing clinical data indicate that atrial fibrosis is a critical common left atrial (LA) substrate in AF patients (pts).

Five-Year Follow-Up After Catheter Ablation of Persistent Atrial Fibrillation Using the Stepwise Approach and Prognostic Factors for Success

Background—In the meantime, catheter ablation is widely used for the treatment of persistent atrial fibrillation (AF). There is a paucity of data about long-term outcomes. This study evaluates (1) 5-year single and multiple procedure success and (2) prognostic factors for arrhythmia recurrences after catheter ablation of persistent AF using the stepwise approach aiming at AF termination. Methods and Results—A total of 549 patients with persistent AF underwent de novo catheter ablation using the stepwise approach (2007–2009). A total of 493 patients were included (Holter ECGs ≥every 6 months). Mean follow-up was 59±16 months with 2.1±1.1 procedures per patient. Single and multiple procedure success rates were 20.1% and 55.9%, respectively (80% off antiarrhythmic drug). Antiarrhythmic drug–free multiple procedure success was 46%. Long-term recurrences (n=171) were paroxysmal AF in 48 patients (28%) and persistent AF/atrial tachycardia in 123 patients (72%). Multivariable recurrent event analysis revealed the following factors favoring arrhythmia recurrence: failure to terminate AF during index procedure (hazard ratio [HR], 1.279; 95% confidence interval [CI], 1.093–1.497; P=0.002), number of procedures (HR, 1.154; 95% CI, 1.051–1.267; P=0.003), female sex (HR, 1.263; 95% CI, 1.027–1.553; P=0.027), and the presence of structural heart disease (HR, 1.236; 95% CI, 1.003–1.524; P=0.047). AF termination was correlated with a higher rate of consecutive procedures because of atrial tachycardia recurrences (P=0.003; HR, 1.71; 95% CI, 1.20–2.43). Conclusions—Catheter ablation of persistent AF using the stepwise approach provides limited long-term freedom of arrhythmias often requiring multiple procedures. AF termination, the number of procedures, sex, and the presence of structural heart disease correlate with outcome success. AF termination is associated with consecutive atrial tachycardia procedures.

Loss of Pace Capture on the Ablation Line During Pulmonary Vein Isolation Versus “Dormant Conduction”: Is Adenosine Expendable?

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.

Catheter ablation of atrial fibrillation with box isolation of fibrotic areas: Lessons on fibrosis distribution and extent, clinical characteristics, and their impact on long-term outcome.

The BIFA concept (box isolation of fibrotic areas) supplementing pulmonary vein isolation (PVI) was implemented in atrial fibrillation (AF) patients with fibrotic atrial cardiomyopathy (FACM) to improve catheter ablation outcomes.

Ablation of Idiopathic Ventricular Tachycardia

Idiopathic ventricular arrhythmias occur in patients without structural heart disease. They can arise from a variety of specific areas within both ventricles and in the supravalvular regions of the great arteries. Two main groups need to be differentiated: arrhythmias from the outflow tract (OT) region and idiopathic left ventricular, so-called fascicular, tachycardias (ILVTs). OT tachycardia typically originates in the right ventricular OT, but may also occur in the left ventricular OT, particularly in the sinuses of Valsalva or the anterior epicardium or the great cardiac vein. Activation mapping or pace mapping for the OT regions and mapping of diastolic potentials in ILVTs are the mapping techniques that are typically used. The ablation of idiopathic ventricular arrhythmias is highly successful, associated with only rare complications. Newly recognized entities of idiopathic ventricular tachycardias are those originating in the papillary muscles and in the atrioventricular annular regions.

Reduction of Radiation Exposure in Atrial Fibrillation Ablation Using a New Image Integration Module: A Prospective Randomized Trial in Patients Undergoing Pulmonary Vein Isolation

Recently, a new image integration module (IIM, CartoUnivu™ Module) has been introduced to combine and merge fluoroscopy images with 3‐dimensional‐(3D)‐electroanatomical maps (Carto® 3 System) into an accurate 3D view. The aim of the study was to investigate the influence of IIM on the fluoroscopy exposure during pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) in a prospective randomized trial.

Catheter ablation in a patient with paroxysmal atrial fibrillation and partial anomalous pulmonary vein connection.

A 76-year-old woman with almost daily episodes of highly symptomatic drug refractory paroxysmal atrial fibrillation (AF) was referred to our center for catheter ablation. The left atrium (LA) was not dilated with 39 mm. Preprocedural imaging of the patient was done using a 64-slice CT scanner. It showed an anomalous right upper pulmonary vein (RUPV) connecting to the superior vena cava (SVC) in close proximity to the branching of the inominate veins (Fig. 1A). A circular catheter-guided ablation approach with two transseptal punctures and a 3-D mapping system with image integration (Carto, Biosense Webster, Diamond Bar, CA, USA) was performed with continuous monitoring of LA-to-pulmonary-vein-conduction. Circumferential ablation lines were placed in the LA around the funnel of the 2 left PVs and the right lower PV at the LA level. Radiofrequency ablation was delivered with a 3.5 mm irrigated-tip catheter (Navistar RMT Thermocool, BiosenseWebster). The complete isolation of the left PVs and around the right lower PV was the electrophysiological endpoint. To evaluate the electrical activity of the anomalous RUPV, a 10-pole circular catheter (Lasso Catheter, Biosense Webster) was placed inside the ostium and contrast medium was delivered through a steerable sheath (Agilis, St. Jude Medical, St. Paul, MN, USA) (Fig. 1B). The electrograms of the circular catheter in the RUPV did not show any active or passive electrical activity and, therefore, no electrical disconnection/isolation was necessary in this vein.

Global multielectrode contact mapping plus ablation with a single catheter: Preclinical and preliminary experience in humans with atrial fibrillation

One question for the technological advancement of catheter ablation of atrial fibrillation (AF) is whether a creative new concept can combine and even improve the diagnostic mapping options of single‐tip and basket catheters with the simplicity of the use of balloon catheters for ablation. Herein, we describe the first in‐human experience with a single catheter offering such a complete solution.