Premature atrial stimulation and His bundle recordings were performed in 6 patients with pre-excitation (WPW) syndrome. The ventricular rates during bursts of atrialflutter and atrialfibrillation triggered by the earliest impulses depended on the functional properties of the accessory pathway. In 3 patients in whom the effective refractory period of the accessory pathway was longer than that of...

BACKGROUND Atrial fibrillation (AF) may cause life-threatening ventricular arrhythmias in patients with Wolff-Parkinson-White syndrome. We prospectively evaluated the effects of ibutilide on the conduction system in patients with accessory pathways (AP). METHODS AND RESULTS In part I, we gave ibutilide to 22 patients (18 men, 31+/-13 years of age) who had AF during electrophysiology study, in...

Catheter ablation for septal accessory pathways is occasionally associated with complications, such as atrioventricular block, since the septal region is a complex anatomical structure containing the atrioventricular conduction system. Therefore, we designed a signal separator composed of an inductance-capacitance network with which the local electrogram at the ablation site could be continuous...

OBJECTIVES The aim of this study was to determine whether noninvasive imaging of cardiac electrophysiology (NICE) is feasible in patients with Wolff-Parkinson-White (WPW) syndrome in the clinical setting of a catheter laboratory and to test the accuracy of the noninvasively obtained ventricular activation sequences as compared with that of standard invasive electroanatomic mapping. BACKGROUND...

During the electrophysiologic study of 435 patients referred for evaluation of WolffParkinson-White syndrome, 42 (10%) had preexcited reciprocating tachycardia (defined as a macroreentrant tachycardia that used an accessory atrioventricular [AV] pathway for antegrade conduction). The ages of the patients ranged from 9 to 67 years (27 + 14). Thirty-three were male patients, nine female, and eigh...

INTRODUCTION Recent studies have demonstrated that the most common site of accessory pathway conduction block following the introduction of a premature atrial stimulus during atrial pacing is between the accessory pathway potential and the ventricular electrogram, consistent with block at the ventricular insertion of the accessory pathway. However, no prior study has evaluated the site of condu...

Wolff-Parkinson-White syndrome is a disorder characterized by presence of an accessory pathway which predisposes patients to tachyarrhythmias and sudden death. Among patients with WPW syndrome, atrioventricular reentrant tachycardia (AVRT) is the most common arrhythmia, accounting for 95% of re-entrant tachycardias. It has been estimated that one-third of patients with WPW syndrome have atrial ...

Retrograde atrial preexcitation following premature ventricular beats during reciprocating tachycardia in the Wolff-Parkinson-White syndrome. Eur J Cardiol 3: 283, 1975 28. Rosen KM, Denes P, Wu D, Dhingra RC: Electrophysiological diagnosis and manifestation of dual A-V nodal pathways. In Conduction System of the Heart, edited by Wellens HJJ, Lie H, Janse MJ. The Netherlands, H.E. Stenfert Kroe...

The importance of activation sequence of an atrioventricular junctional reentrant (AVJRe) circuit, before delivery of an extrastimulus, has received little attention in studies concerned with clinical tachycardias. In this study a change in activation sequence was accomplished using bidirectional activation (V-A sequential pacing) during the basic drive (V1A1-V1A1). It was noted that, compared ...

OBJECTIVE Wolff-Parkinson-White (WPW) syndrome presents with paroxysmal supraventricular tachycardia and is characterized by electrocardiographic (ECG) findings of a short PR interval and a delta wave. The objective of this study was to evaluate the electrophysiological properties of children with WPW syndrome and to develop an algorithm for the management of these patients with limited access ...