We read the article by Okumura et al. [1] with great interest. The authors reported an ablation strategy applying manifest entrainment to treat adenosine triphosphate (ATP)-sensitive atrial tachycardia (AT) originating from the perinodal region. However, we have some concerns regarding the electrophysiological diagnosis of the tachycardia. The exclusion of atrioventricular nodal reentrant tachy...

BACKGROUND Atrioventricular nodal reentrant tachycardia (AVNRT) is the commonest regular supraventricular tachyarrhythmia. Ablation in the area of slow pathway (SP) has been successfully implemented in everyday clinical electrophysiological practice for more than 20 years. Although the procedure is generally regarded as effective and safe, data on long-term effects and predictors of success or ...

The electrophysiology of antidromic reentry, a less common phenomenon than orthodromic reentry, remains a poorly understood aspect of the Wolff-Parkinson-White (WPW) syndrome. We used a pacing model of ventricular preexcitation in patients without WPW, so that electrophysiological events in the normal pathway during atrial extrastimulation (A1-A2 technique) could be precisely delineated without...

Studies have shown that in patients with paroxysmal supraventricular tachycardia (SVT), spontaneous or stimulated atrial premature depolarizations (APD) falling within a specific portion of the relative refractory period of the atrioventricular (A-V) conduction system initiate SVT. The present study was designed to determine whether the A-V nodal conduction delay these APDs exhibit, or their co...

Studies have shown that in patients with paroxysmal supraventricular tachycardia (SVT), spontaneous or stimulated atrial premature depolarizations (APD) falling within a specific portion of the relative refractory period of the atrioventricular (A-V) conduction system initiate SVT. The present study was designed to determine whether the A-V nodal conduction delay these APDs exhibit, or their co...

coronary sinus selectively affect slow pathway function. The current study compares the safety, efficacy, and electrophysiological effects of these two techniques in a prospective, randomized fashion. Methods and Results. Fifty consecutive patients with typical AVNRT were randomly assigned to receive radiofrequency lesions either anteriorly (n=22) or posteriorly (n=28). If the initial approach ...

T he paper by Brugada et a1l in this issue of Circulation adds importantly to mounting evidence that the anisotropic passive electrical properties of cardiac muscle play an important role in atrial2-4 and ventricular5-6 reentrant arrhythmias. The anisotropic properties involved are determined at a microscopic size scale (<200 jam) by the alignment of cardiac myocytes, their complex shapes, the ...

INTRODUCTION The purpose of this study was to prospectively compare the effects of complete and partial ablation of slow pathway function on the fast pathway effective refractory period (ERP). METHODS AND RESULTS The subjects were 20 patients (mean age 43 +/- 13 years) with atrioventricular nodal reentrant tachycardia (AVNRT), no structural heart disease, and easily inducible AVNRT. Autonomic...

BACKGROUND Atrioventricular (AV) nodal reentrant tachycardia is classically described as a reentrant rhythm entirely contained within the compact AV node. Although the concepts of longitudinal dissociation of two intranodal pathways and a distal common pathway are accepted, the proximal portion of the circuit remains undefined. Current reports suggest that the two pathways may be separable by a...

INTRODUCTION AV nodal reentrant tachycardia (AVNRT) is not always reproducibly inducible. The purpose of this study was to determine the mechanisms responsible for the lack of reproducible induction of AVNRT. METHODS AND RESULTS The induction of AVNRT was assessed with atrial burst pacing, and with atrial and ventricular programmed stimulation, each with one and two extrastimuli, in 103 patie...