BACKGROUND The response to right ventricular (RV) entrainment is useful to distinguish atypical AV node reentrant tachycardia from AV reentrant tachycardia using a septal accessory pathway. Whether entrainment can differentiate between AV node reentrant tachycardia and AV reentrant tachycardia in patients with long-RP tachycardia has not been systematically validated. METHODS AND RESULTS Twen...

BACKGROUND The aim of this study was to test the electrophysiological effects of continuous enhanced vagal tone on dual atrioventricular (AV) nodal and accessory pathways. METHODS AND RESULTS This study included 10 patients with typical, slow-fast AV nodal reentrant tachycardia (AVNRT) and 10 patients with AV reciprocating tachycardia. Electrophysiological data were measured before and during...

We performed electrophysiologic studies before and after oral administration of disopyramide phosphate, 200 mg every 6 hours, in 20 patients with atrioventricular (AV) reentrant tachycardia using a retrogradely conducting accessory pathway. Disopyramide markedly depressed retrograde accessory pathway conduction by increasing the mean ventricular paced cycle length that produced ventriculoatrial...

In the normal heart, the atrioventricular node (AVN) is part of the sole pathway between the atria and ventricles, and is responsible for the appropriate atrial-ventricular delay. Under normal physiological conditions, the AVN controls appropriate frequency-dependent delay of contractions. The AVN also plays an important role in pathology: it protects ventricles during atrial tachyarrhythmia, a...

45 years age female presented with acute onset palpitation. On examination she had tachycardia and a blood pressure of 116/70. ECG was suggestive of NCT (Fig. 1). On administration of 6 mg of intravenous adenosine she developed transient AV block followed by irregular wide complex tachycardia (Fig. 2) and systemic hypotension, requiring DC cardioversion. Electrocardiogram in sinus rhythm showed...

Electrophysiologic studies were performed in 28 patients with documented atrioventricular (AV) nodal reentrant supraventricular tachycardia (SVT) to investigate the presence of AV nodal tissue situated between the tachycardia circuit and both the atrium (upper common pathway, UCP) and the His bundle (lower common pathway, LCP). All patients demonstrated a 1:1 AV relationship during SVT. The stu...

OBJECTIVES This study sought to investigate electrophysiologic characteristics and possible anatomic sites of multiple anterograde slow atrioventricular (AV) node pathways and to compare these findings with those in dual anterograde AV node pathways. BACKGROUND Although multiple anterograde AV node pathways have been demonstrated by the presence of multiple discontinuities in the AV node cond...

BACKGROUND We correlated the electrophysiologic (EP) effects of adenosine with tachycardia mechanisms in patients with supraventricular tachycardias (SVT). METHODS AND RESULTS Adenosine was administered to 229 patients with SVTs during EP study: atrioventricular (AV) reentry (AVRT; n=59), typical atrioventricular node reentry (AVNRT; n=82), atypical AVNRT (n=13), permanent junctional reciproc...