Variability of Ventricular Excitation Interval Does Not Reflect Fluctuation in Atrial Excitation Interval during Exercise in Humans: AV Nodal Function as Stabilizer
نویسندگان
چکیده
منابع مشابه
Complex AV nodal dynamics during ventricular-triggered atrial pacing in humans.
In vitro experiments have shown that the complexity of atrioventricular nodal (AVN) conduction dynamics increases with heart rate. Although complex AVN dynamics (e.g., alternans) have been observed clinically, human AVN dynamics during rapid pacing have not been systematically investigated. We studied such dynamics during ventricular-triggered atrial pacing in 37 patients with normal AVN functi...
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SUMMARY Alternate patterns of premature ventricular excitation have been observed during induced atrial bigeminy in 18 subjects, including five normal volunteers. Each study was performed in the cardiac catheterization suite where a transvenous catheter electrode was positioned in the right atrium. Coupled or paired stimuli were delivered to the atrium by an isolated battery-powered source at a...
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VENTRICULAR fusion beats are observed in a variety of circumstances whenever two impulses depolarize different parts of the ventricles simultaneously.' The resulting electrocardiographic complex is a mixture, or fusion, of the two responses. Special opportunities for quantitative studies of ventricular fusion beats were found in patients with Stokes-Adams disease after electric pacemakers were ...
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BACKGROUND Atrial fibrillation is usually thought of as a "random" pattern of circulating wavelets. However, local atrial activation should be influenced by the constant anatomy and receding tail of refractoriness from the previous activation. The general tendency for wave fronts to follow paths of previous excitation has been termed "linking." We examined intra-atrial electrograms recorded dur...
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BACKGROUND Ritter's method is a tool used to optimize AV delay in DDD pacemaker patients with normal left ventricular function only. The goal of our study was to evaluate Ritter's method in AV delay-interval optimization in patients with reduced left ventricular function. METHODS Patients with implanted DDD pacemakers and AVB III degrees were assigned to one of two groups according to ejectio...
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ژورنال
عنوان ژورنال: The Journal of Physiological Sciences
سال: 2006
ISSN: 1880-6546,1880-6562
DOI: 10.2170/physiolsci.rp002705