introduction: the aim of the present study was to determine direct effects of no modulation on protective electrophysiological properties of atrioventricular node (av node) in the experimental model of af in rabbit. methods: isolated perfused rabbit av nodal preparations were used in two groups. in the first group (n=7), lname (50μm) was applied. in the second group (n=12), different concentrat...

Concealed conduction is a phenomenon which could be rarely seen on the surface of electrocardiography (ECG). The surface ECG must be evaluated carefully for determination of concealed conduction. Because concealed conduction manifests itself in different shape and level. This evaluation could prevent misdiagnosis and unappropriate treatment. In this chapter we want to contribute to understandin...

THE CONCEPT of concealed conduction was introduced into electrocardiography to explain a lengthening of, or change in, the refractory period of the atrioventricular conduction system caused either by atrial activity that fails to propagate to the ventricles or by ventricular activity that fails to reach the atria. Standard electrocardiograms do not provide a direct demonstration of the partial ...

Objectives: Dual pathways have a determinant role in the occurrence of atrio nodal tachyarrhythmia (AVNRT). The aim of present study is to determine the role of slow pathway (SP) in the concealment zone and protective role of AV node during atrial fibrillation (AF). Material &Methods: In 7 isolated nodal rabbit preparation zone of concealment and concealed conduction is quantified by Specif...

Alternating WEnckebach periodicity is generally believed to reflect bilevel block due to horizontal electrophysiologic dissociation in the conducting tissues. We describe a case of atrial pacing-induced atrioventricular nodal alternating Wenckebach periodicity with concealed reentry in a longitudinally dissociated AV conduction system. Three observations support this unique mechanism: Concealed...

Although concealed conduction in the atrioventricular node (AVN) has been the focus of numerous experimental and clinical studies, little is known about the differential effects on AVN functional behavior of prior concealed retrograde impulse penetration alone vs prior anterograde or dual AVN activation. This study was undertaken specifically to investigate this aspect of human AVN physiology i...

Although concealed conduction in the atrioventricular node (AVN) has been the focus of numerous experimental and clinical studies, little is known about the differential effects on AVN functional behavior of prior concealed retrograde impulse penetration alone vs prior anterograde or dual AVN activation. This study was undertaken specifically to investigate this aspect of human AVN physiology i...

CONCEALED CONDUCTION in the atrioventricular (AV) junction in association with coordinated atrial activity is a well-recognized phenomenon,1-3 recently confirmed with new technics in animal experiments.4-6 Its operation in atrial fibrillation has received less attention, although it appears to offer the best explanation for the characteristic irregularity of the ventricular responses.7 11 It is...

CONCEALED CONDUCTION in the atrioventricular (AV) junction in association with coordinated atrial activity is a well-recognized phenomenon,1-3 recently confirmed with new technics in animal experiments.4-6 Its operation in atrial fibrillation has received less attention, although it appears to offer the best explanation for the characteristic irregularity of the ventricular responses.7 11 It is...