Exercise-induced atrioventricular (AV) block in patients with normal AV conduction at rest is rare. Herein, we describe the case of a 67-year-old woman with normal 1 : 1 AV conduction at rest, who developed complete AV block during a treadmill test. Our patient complained of effort-related dizziness and dyspnea, which had been ongoing for 3 months. The patient's physical examination was normal....

Paroxysmal supraventricular tachycardia (PSVT) is commonly caused by reentry within the atrioventricular (AV) node. This arrhythmia was abolished by operative dissection of the AV junction in a patient with disabling tachycardia that was not controlled by drugs. The operation was intended to create complete AV block, but AV conduction persisted after surgery. An electrophysiologic study 1 year ...

Goldberger has claimed that his augmented unipolar limb leads (aV) are identical except for a 50 per cent larger amplitude and interchangeable with Wilson's original V leads, but this claim was not supported by quantitative evidence. The advantage of larger amplitudes explains the increasing preference for the aV leads. A quantitative comparison between V and aV leads revealed such tremendous v...

Paroxysmal supraventricular tachycardia (PSVT) is commonly caused by reentry within the atrioventricular (AV) node. This arrhythmia was abolished by operative dissection of the AV junction in a patient with disabling tachycardia that was not controlled by drugs. The operation was intended to create complete AV block, but AV conduction persisted after surgery. An electrophysiologic study 1 year ...

BACKGROUND Catheter ablation of accessory atrioventricular (AV) connections using radiofrequency current has been demonstrated to be effective in the majority of patients with the Wolff-Parkinson-White syndrome or paroxysmal supraventricular tachycardia involving a concealed accessory AV connection. However, electrogram criteria have not been established to guide attempts at radiofrequency cath...

BACKGROUND Nonpharmacological ventricular rate control in atrial fibrillation (AF) without producing atrioventricular (AV) block remains a clinical challenge. We investigated the hypothesis that autologous dermal fibroblast (ADF) injection into the AV nodal area would reduce ventricular response during AF without causing AV block. METHODS AND RESULTS Fourteen pigs underwent electrophysiology ...

BACKGROUND Aortic valve (AV) disease presents critical situations requiring surgery in over 2% of the US population and is increasingly the reason for cardiac surgery. Throughout the AV cycle, mechanical forces of multiple types and varying intensities are exerted on valve leaflets. The mechanisms whereby forces regulate leaflet homeostasis are incompletely understood. We used a novel flow bior...

The reentrant pathways underlying different types of atrioventricular (AV) nodal reentrant tachycardia have not yet been elucidated. This study was performed to optically map Koch's triangle and surrounding atrial tissue in an isolated canine AV nodal preparation. Multiple preferential AV nodal input pathways were observed in all preparations (n=22) with continuous (73%, n=16) and discontinuous...

BACKGROUND The site of the reentrant circuit in atrioventricular (AV) junctional reentrant tachycardia has not been defined; in particular, the existence of a common pathway of AV nodal tissue above the reentrant circuit is controversial. METHODS AND RESULTS Two types of AV junctional reentrant tachycardia were induced in each of three patients at electrophysiological study. In one type of ta...

OBJECTIVES The purpose of this study was to test the hypothesis that cardiac-directed expression of adenylyl cyclase VI (AC(VI)) facilitates atrioventricular (AV) nodal conduction. BACKGROUND Cardiac-directed expression of AC(VI), unlike other strategies to increase cyclic adenosine monophosphate generation, reduces mortality in murine cardiomyopathy. Recent reports suggest that AC(VI) expres...