Seigo Yamashita

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BACKGROUND Specific noninvasive signal processing was applied to identify drivers in distinct categories of persistent atrial fibrillation (AF). METHODS AND RESULTS In 103 consecutive patients with persistent AF, accurate biatrial geometry relative to an array of 252 body surface electrodes was obtained from a noncontrast computed tomography scan. The(More)
BACKGROUND Although mitral isthmus (MI) ablation in atrial fibrillation (AF) patients has been shown to be an effective ablative strategy, the establishment of the bidirectional conduction block of the MI is technically challenging. We investigated the usefulness of a steerable sheath for MI ablation in patients with persistent AF and its impact on the(More)
BACKGROUND The elimination of transient pulmonary vein (PV) reconduction (dormant PV conduction) revealed by adenosine in addition to PV isolation reduced the atrial fibrillation (AF) recurrence after catheter ablation. The dormant PV conduction is induced in approximately half of the AF patients that undergo PV isolation. The present study compared the(More)
BACKGROUND Although several clinical variables are associated with the recurrence of atrial fibrillation (AF) following catheter ablation, the influence of renal function remains to be determined. OBJECTIVE To evaluate the association of renal function with the outcome of the paroxysmal AF ablation. METHODS 224 patients underwent catheter ablation for(More)
BACKGROUND Recurrence of atrial fibrillation (AF) after successful pulmonary vein isolation (PVI) occurs mainly due to the reconnection of the once isolated PV. Although provocation and elimination of the early pulmonary vein reconnection (EPVR) soon after PVI has been widely performed to improve the outcome, AF recurrence due to subsequent PV reconnections(More)
Although catheter ablation targeting the pulmonary vein (PV) is a well-known therapy for patients with paroxysmal atrial fibrillation (PAF), ectopic firings from the superior vena cava (SVC) can initiate PAF. The purpose of this study was to investigate predictors of SVC firing. The subjects included 336 consecutive PAF patients (278 males, age 56.1 ± 10.8(More)
BACKGROUND intravenous administration of adenosine triphosphate (ATP) is used to induce transient pulmonary vein (PV) reconduction (dormant PV conduction) following PV isolation. This study investigated the detailed characteristics of dormant PV conduction in patients with atrial fibrillation (AF) who underwent catheter ablation. METHODS two hundred sixty(More)
BACKGROUND Nonischemic cardiomyopathy is a heterogeneous condition providing a favorable substrate for ventricular tachycardia (VT). OBJECTIVE The purpose of this study is to further characterize the substrate in a subset of postmyocarditis patients with epicardial-only scar. METHODS Twelve postmyocarditis patients (11 male, 49 ± 14 years, left(More)
BACKGROUND The early repolarization (ER) pattern is associated with an increased risk of arrhythmogenic sudden death. However, strategies for risk stratification of patients with the ER pattern are not fully defined. OBJECTIVES This study sought to determine the role of electrophysiology studies (EPS) in risk stratification of patients with ER syndrome.(More)
The early repolarization (ER) pattern has historically been regarded as a benign ECG variant. However, in recent years this view has been challenged based on multiple reports linking the ER pattern with an increased risk of sudden cardiac death. The mechanistic basis of ventricular arrhythmogenesis in ER syndrome is presently incompletely understood.(More)