OBJECTIVES This study assessed the use of adenosine triphosphate (ATP) in the noninvasive diagnosis of concealed accessory pathway (AP) and dual atrioventricular (AV) node physiology in patients with inducible AV reentrant tachycardia (AVRT). BACKGROUND Administration of ATP during sinus rhythm identifies dual AV node physiology in 76% of patients with inducible sustained slow/fast AV nodal r...

OBJECTIVES In the present study, we evaluated sinus and atrioventricular (AV) node electrophysiology of endurance athletes and untrained individuals before and after autonomic pharmacologic blockade. BACKGROUND Endurance athletes present a higher prevalence of sinus bradycardia and AV conduction abnormalities, as compared with untrained individuals. Previous data from our laboratory suggest t...

Relative contributions of the atria and the atrioventricular (AV) node to AV conduction were studied in isolated, blood-perfused dog hearts. The functional refractory period of the atria, although shorter than that of the AV node, determined the functional refractory period of the entire transmission system in 50% of the hearts. Slow atrial conduction of early beats greatly influenced the shape...

Introduction: The present study is aimed to evaluate electrophysiological remodeling of atrioventricular (AV) node and ventricular conduction during experimental atrial fibrillation (AF) model in isolated heart of cirrhotic rats. Methods: Cirrhosis-induced electrophysiological remodeling was evaluated in 24 isolated retrogradely perfused rat hearts in 2 groups (control and cirrhotic). Cirrho...

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...

Abstract Introduction: Isolated perfused heart models such as perfusion and superfusion are commonly used for mammalian heart research. However, there are several fundamental limitations in the current techniques. In perfusion model, a suitable cannula is connected to the aorta and the perfusion is retrogradely performed. But, electrode displacement is a potential unwanted event resulted fr...

OBJECTIVES We sought to investigate the long-term efficacy of slow-pathway catheter ablation in patients with spontaneous, documented paroxysmal supraventricular tachycardia (PSVT) and dual atrioventricular (AV) node pathways but without inducible tachycardia. BACKGROUND The lack of reproduction of clinical PSVT by programmed electrical stimulation, which is not uncommon in AV node reentrant ...

BACKGROUND Linear accelerator-based stereotactic radiosurgery delivered to cardiac arrhythmogenic foci could be a promising catheter-free ablation modality. We tested the feasibility of in vivo atrioventricular (AV) node ablation in swine using stereotactic radiosurgery. METHODS AND RESULTS Five Large White breed swine (weight 40-75 kg; 4 females) were studied. Single-chamber St Jude pacemake...

The spread of excitation wave fronts over the atrial septum of puppies, adult dogs, and rabbits was studied in vitro by extracellular measurements with a 50/x-diameter electrode. Wave front spread through the AV node of puppies and rabbits was determined, and the functional location of the junctional region between atrial muscle and the AV node was evaluated during antegrade atrial and retrogra...

Using His bundle recordings and ventricular stimulation retrograde conduction was studied in 57 cases of complete AV block. VA conduction was observed in 13 patients. Of the 13, 12 had AV block distal to H, and during cardiac pacing 5 of them showed a retrograde His bundle potential. In all cases the AV node-His pathway was implicated in the transmission of the retrograde impulse. There was no ...