Electrophysiological correlation and prognostic impact of heat shock protein 27 in atrial fibrillation.

Background: Heat shock protein (HSP) 27 is related to the pathogenesis of AF. However, the clinical relationship between HSP27 and AF is unclear. The present study was conducted to determine the clinical relationship between HSP27 and atrial fibrillation (AF).

Arrhythmogenic difference between the left and right atria in a canine ventricular pacing-induced heart failure model of atrial fibrillation.

Background: The detail of biatrial activation during sustained atrial fibrillation (AF) has not been investigated until now.

Methods: Five dogs with right ventricular pacing-induced congestive heart failure (CHF) and five normal dogs were included. Biatrial endocardiac mapping was performed using noncontact mapping system.

Characteristics of fibrillatory activities during spontaneous termination of paroxysmal atrial fibrillation: new insight from high-density right atrium frequency mapping.

Background: Sinus node (SN) activity is difficult to assess during atrial fibrillation (AF). The aim of the present study was to investigate SN activity by frequency analysis during AF.

Methods: Thirteen patients with paroxysmal AF and atrial flutter in the right atrium (RA) underwent 3-dimensional noncontact mapping.

Characteristics and significance of very early recurrence of atrial fibrillation after catheter ablation.

Introduction: Early restoration of sinus rhythm following ablation of atrial fibrillation (AF) facilitates reverse atrial remodeling and improves the long-term outcome. The purpose of this study was to determine the predictors and outcome in patients with very early AF recurrences (< 2 days).

Methods And Results: Ablation was performed in 339 consecutive AF patients (paroxysmal AF = 262).

Paradoxical aging changes of the atrioventricular nodal properties in patients with atrioventricular nodal re-entrant tachycardia.

Background: This study aimed to investigate the impact of aging on electrophysiological characteristics in patients with atrioventricular nodal re-entrant tachycardia (AVNRT).

Methods And Results: The 2,111 patients who underwent an electrophysiological study and radiofrequency (RF) catheter ablation of AVNRT were enrolled. The patients were divided into 4 groups according to age (group 1: < 20 years; group 2: 20-39 years; group 3: 40-59 years; and group 4: ≥ 60 years).

Quantitative analysis of quantity and distribution of epicardial adipose tissue surrounding the left atrium in patients with atrial fibrillation and effect of recurrence after ablation.

Epicardial adipose tissue (EAT) contains ganglionated plexuses and adipocytes that can affect the pathogenesis of atrial fibrillation (AF). The aim of this study was to quantify the EAT surrounding the left atrium (LA) and correlate it with occurrence of AF and outcome after catheter ablation. EAT was evaluated using 64-slice multidetector computed tomography in 68 patients with AF and 34 controls.

The correlation between ventricular repolarization and clinical severity of spinal cord injuries.

Background: Alteration in ventricular repolarization has been reported in patients with spinal cord injuries (SCIs). However, its clinical impact remains unclear.

Objective: The purpose of this study was to investigate the correlation between SCIs and ventricular repolarization and the associated clinical impact.

Differentiating macroreentrant from focal atrial tachycardias occurred after circumferential pulmonary vein isolation.

Background: Atrial tachycardias (ATs) are commonly observed following catheter ablation of atrial fibrillation (AF). The aim of this study was to identify ECG characteristics that differentiate focal from macroreentrant ATs after circumferential pulmonary vein isolation (CPVI).

Methods And Results: One hundred and twenty ATs that occurred after CPVI were mapped using a 3-dimensional mapping system in 87 patients with AF.

The distance between the vein and lesions predicts the requirement of carina ablation in circumferential pulmonary vein isolation.

Aims: Additional ablation in the pulmonary vein (PV) carina region is sometimes required to achieve electrical isolation following circumferential pulmonary vein isolation (PVI). This study investigated the procedural predictors for the requirement of additional carina ablation to achieve complete electrical isolation with PVI.

Methods And Results: Eighty patients with drug-refractory paroxysmal AF underwent circumferential PVI.

Impact of circulating monocyte CD36 level on atrial fibrillation and subsequent catheter ablation.

Background: Inflammation, an important mechanism in the pathogenesis of atrial fibrillation (AF), can be regulated by CD36 in monocytes.

Objective: The purpose of this study was to test the hypothesis that CD36 in monocytes contributes to the pathogenesis of AF.

Methods: A prospective study that enrolled 87 patients with AF and 70 without AF was conducted.

Gender differences of electrophysiologic characteristics in patients with accessory atrioventricular pathways.

Background: Few epidemiologic data on the gender differences among patients with accessory atrioventricular pathways have been reported.

Objective: The purpose of this study was to investigate the explicit gender differences in electrophysiologic characteristics among patients with accessory atrioventricular pathways.

Methods: A total of 1,821 consecutive patients with accessory atrioventricular pathways were referred to our institution for electrophysiologic study and radiofrequency catheter ablation.

Characterization of the dynamic function of the pulmonary veins before and after atrial fibrillation ablation using multi-detector computed tomographic images.

Understanding pulmonary vein (PV) function before and after catheter ablation can validate the benefit of the treatment and provide mechanistic insight into atrial fibrillation (AF). This study was aimed to investigate the functional remodeling process of PVs by multi-detector computed tomography (MDCT). We assessed the dynamic function of four PVs by MDCT at systolic and diastolic phases.

Atrial substrate properties and outcome of catheter ablation in patients with paroxysmal atrial fibrillation associated with diabetes mellitus or impaired fasting glucose.

Diabetes mellitus has been reported to be an independent risk factor of atrial fibrillation (AF). The present study investigated the atrial substrate properties and clinical outcome of catheter ablation in patients with paroxysmal AF and abnormal glucose metabolism. A total of 228 patients with paroxysmal AF who had undergone catheter ablation for the first time were enrolled.

The impact of age on the electrophysiological characteristics and different arrhythmia patterns in patients with Wolff-Parkinson-White syndrome.

Introduction: Information about the impact of age on the electrophysiological characteristics of accessory pathways (APs) in patients with Wolff-Parkinson-White (WPW) syndrome remains limited.

Methods And Results: A total of 1,885 consecutive patients (mean age 43 ± 17 years, male 61.5%) with WPW syndrome who were referred to the tertiary center for an electrophysiological study and radiofrequency catheter ablation were investigated.

Relationship between arrhythmogenic pulmonary veins and the surrounding atrial substrate in patients with paroxysmal atrial fibrillation.

Introduction: The relationship between pulmonary veins (PVs) with atrial fibrillation (AF) initiating triggers and their surrounding atrial substrate has not been elucidated. We aimed to clarify the atrial substrate properties around the PVs.

Methods And Results: Twenty-three paroxysmal AF patients were studied with the identification of PV initiating triggers.

Different patterns of atrial remodeling after catheter ablation of chronic atrial fibrillation.

Background: Multiple remodeling patterns have been observed after catheter ablation of atrial fibrillation (AF).

Objective: We aimed to clarify the electrical/structural properties associated with recurrences after ablation of chronic AF.

Methods: After a stepwise ablation procedure in 120 consecutive patients with persistent/long-lasting persistent AF, 36 had a recurrence of AF (Group 1/Group 2: recurrence with paroxysmal/persistent AF, n = 16/20).

The impact of diastolic dysfunction on the atrial substrate properties and outcome of catheter ablation in patients with paroxysmal atrial fibrillation.

Background: The presence of diastolic dysfunction increases the risk of atrial fibrillation (AF), and might be associated with the left atrial (LA) substrate. The aim of the present study was to investigate the relationships between the diastolic dysfunction, atrial substrate and outcome of the catheter ablation.

Methods And Results: Eighty-three patients with paroxysmal AF were enrolled.

Gender differences in the clinical characteristics and atrioventricular nodal conduction properties in patients with atrioventricular nodal reentrant tachycardia.

Introduction: The detailed electrophysiological characteristics of the gender differences associated with atrioventricular nodal reentrant tachycardia (AVNRT) have not been clarified. This study investigated the gender-related electrophysiological differences in a large series of patients undergoing radiofrequency catheter ablation.

Methods And Results: A total of 2,088 consecutive AVNRT patients (men/women 869/1,219) who underwent catheter ablation were enrolled in this study.

The impact of age on the electroanatomical characteristics and outcome of catheter ablation in patients with atrial fibrillation.

Background: Previous studies have indicated that atrial fibrillation (AF) in patients over the age of 60 at diagnosis is a risk factor for a substantial increase in cardiovascular events. However, information about the impact of age on the atrial substrate and clinical outcome after catheter ablation of AF is limited.

Methods: This study included 350 patients (53 ± 12 years, 254 males) who underwent circumferential pulmonary vein isolation (CPVI) of AF, guided by a NavX mapping system.

Prognostic implications of the high-sensitive C-reactive protein in the catheter ablation of atrial fibrillation.

Previous studies have reported that increased high-sensitive C-reactive protein (hs-CRP) levels are associated with an inflammatory state. This study investigated the association among hs-CRP, substrate properties, and long-term clinical outcomes after catheter ablation of atrial fibrillation (AF). A total of 137 patients with AF (54 +/- 13 years) who underwent mapping and catheter ablation were included.

The novel electrophysiology of complex fractionated atrial electrograms: insight from noncontact unipolar electrograms.

Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping.

Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF).

Methods: Twenty patients (age 55 +/- 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included.

Cavotricuspid isthmus: anatomy, electrophysiology, and long-term outcome of radiofrequency ablation.

The cavotricuspid isthmus (CTI) had a complex architecture with an anisotropic conduction property. An incremental pacing from the low right atrial isthmus produced a conduction delay and block, and initiated atrial flutter. Radiofrequency catheter ablation of the CTI was very effective in eliminating the typical atrial flutter.

Spatiotemporal organization of the left atrial substrate after circumferential pulmonary vein isolation of atrial fibrillation.

Background: There is a paucity of data regarding the mechanism of maintaining atrial fibrillation (AF) after pulmonary vein isolation (PVI) in patients with AF. The aim of this study was to examine the impact of circumferential PVI on the left atrial (LA) substrate characteristics.

Methods And Results: Seventy-two AF patients (age, 53+/-11 years) underwent mapping and catheter ablation using an NavX system.

Characteristics of complex fractionated electrograms in nonpulmonary vein ectopy initiating atrial fibrillation/atrial tachycardia.

Background: Nonpulmonary vein (PV) ectopy initiating atrial fibrillation (AF)/atrial tachycardia (AT) is not uncommon in patients with AF. The relationship of complex fractionated atrial electrograms (CFAEs) and non-PV ectopy initiating AF/AT has not been assessed. We aimed to characterize the CFAEs in the non-PV ectopy initiating AF/AT.

The impact of catheter ablation on the dynamic function of the left atrium in patients with atrial fibrillation: insights from four-dimensional computed tomographic images.

Introduction: Elucidating the functional properties and remodeling process of the entire left atrium (LA) is important not only for offering the mechanistic insight into atrial fibrillation (AF) but also for assessing the effectiveness of catheter ablation.

Methods: We included 65 patients with paroxysmal AF and 29 controls. Baseline multidetector computed tomography (MDCT) was acquired in all subjects and a follow-up MDCT was available in 48 patients after pulmonary vein and LA ablation.