A new mechanism for atrioventricular nodal gap-vagal modulation of conduction.
نویسندگان
چکیده
منابع مشابه
A new mechanism for atrioventricular nodal gap-vagal modulation of conduction.
The well-known paradoxic behavior of atrioventricular conduction, the so-called gap phenomenon, that occurs when impulses within a certain range of coupling intervals are blocked while impulses with shorter coupling intervals are conducted is attributed to differences in properties of refractoriness in neighboring regions of the conduction system. In contrast, in the present study a model was d...
متن کاملVentriculophasic modulation of atrioventricular nodal conduction in humans.
BACKGROUND Baroreceptor-mediated phasic changes in vagal tone have been hypothesized to cause ventriculophasic sinus arrhythmia (VPSA). The objectives of this study were to demonstrate ventriculophasic modulation of AV nodal conduction and to substantiate the role of the baroreflex on ventriculophasic AV nodal conduction (VPAVN) by pharmacological perturbation of parasympathetic tone. METHODS...
متن کاملHeart Rate and Atrioventricular Nodal Conduction Mechanism and Physiological Implications
This study 1) compares the negative chronotropic and dromotropic actions of adenosine in guinea pig, rat, and rabbit hearts; 2) investigates the mechanism(s) for the different responses; and 3) determines the physiological implications. Isolated perfused hearts were instrumented for measurement of atrial rate and atrioventricular (AV) nodal conduction time. Differences in metabolism of adenosin...
متن کاملFocal pharmacological modulation of atrioventricular nodal conduction via implantable catheter: a novel therapy for atrial fibrillation?
BACKGROUND Pharmacological ventricular rate control is an acceptable atrial fibrillation (AF) therapy limited by systemic toxicity. We postulate that focal catheter-based drug delivery into the atrioventricular nodal (AVN) region may effectively control ventricular rate during AF without systemic toxicity. This study evaluated the effects of focally administered acetylcholine on AVN conduction ...
متن کاملReevaluation of enhanced atrioventricular nodal conduction: evidence to suggest a continuum of normal atrioventricular nodal physiology.
The syndrome of enhanced atrioventricular nodal (AVN) conduction has been defined arbitrarily by: AH interval during normal sinus rhythm (AH-NSR) less than or equal to 60 msec; shortest right atrial pacing cycle length (PCL) maintaining 1:1 AVN conduction (shortest PCL 1:1) less than or equal to 300 msec; and at the shortest PCL 1:1, an increase in the AH interval from AH-NSR (delta AH) less th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Circulation
سال: 1989
ISSN: 0009-7322,1524-4539
DOI: 10.1161/01.cir.79.2.417