OBJECTIVES This study sought to define the electrophysiologic and electrocardiographic characteristics of fast-slow atrioventricular nodal reentrant tachycardia (AVNRT). BACKGROUND In fast-slow AVNRT the retrograde slow pathway (SP) is located in the posterior septum, whereas the anterograde fast pathway (FP) is located in the anterior septum; however, exceptions may occur. METHODS Twelve p...

To characterize age-related changes in beta-adrenergic responsiveness and to test the hypothesis that an increase in the effects of adenosine contribute to impaired beta-adrenergic responsiveness, Fischer 344 rat right atria (RA), left atria (LA), and left ventricular trabeculae carnae were exposed to the beta-receptor agonist isoproterenol (ISO), followed by four doses of the selective adenosi...

Abstract Introduction Inaccurate mapping and ablation of left-lateral concealed AP can result in mitral isthmus conduction block, mimicking concentric retrograde activation. AVRT recurrences are frequent because leaves the through intact. Case Report A 50-years-old patient with history previous ablations underwent third redo procedure due to reoccurrence SVT. Quadripolar catheters were placed H...

BACKGROUND Longitudinal dissociation of an anatomic pathway into 2 electrophysiologically distinct pathways has been hypothesized as a basis for localized AV nodal reentry and supraventricular arrhythmias. METHODS AND RESULTS Extracellular bipolar and intracellular microelectrodes were used to record activation in the superfused rabbit AV junction. A subset of rabbit hearts (n=19 of 72) demon...

Since the seminal paper by Haissaguerre et al. (1) describing the importance of pulmonary vein (PV) triggers in the initiation of paroxysmal atrial fibrillation (AF), PV isolation has become the cornerstone of catheter ablation for AF, demonstrating acceptable results (2,3). By contrast, reported long-term success rates after catheter ablation for persistent or long-standing persistent AF are s...

introduction the sensation of palpitations may either be the initial or the only symptom of cardiac arrhythmia. we describe a case of a visible clear temporal relationship between standard doses of oxazepam and palpitation. case presentation a 48-year-old man presented to the cardiac care unit with systolic heart failure. he was commenced on a medication regimen of routine drugs of patient’s he...

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...

Atrial fibrillation requires a trigger that initiates the arrhythmia and substrate that favors perpetuation. Cardiac mapping is necessary to locate triggers and substrate so that an ablation strategy can be optimized. The most commonly used cardiac mapping approach is isochronal or activation mapping, which aims to create a spatial model of electrical wavefront propagation. Historically, activa...