Spontaneous tachyarrhythmias after cholinergic suppression in the isolated perfused canine right atrium.
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منابع مشابه
Spontaneous tachyarrhythmias after cholinergic suppression in the isolated perfused canine right atrium.
Atrial fibrillation occurs spontaneously after bradycardia induced by acetylcholine infusion or vagal stimulation. To determine the mechanism of initiation of this tachyarrhythmia, we infused acetylcholine (5 ml, 10(-3.5) M) into Krebs-Henseleit-perfused isolated canine right atria (n = 10). Unipolar electrograms were recorded from 250 sites simultaneously during control rhythms, pacing (cycle ...
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Cholinergic agonists and vagal stimulation potentiate the inducibility of atrial fibrillation. To describe the activation patterns and determine the mechanisms that sustain cholinergic fibrillation, tachyarrhythmias were induced with a single extrastimulus in the isolated Krebs-Henseleit-perfused canine right atrium (n = 11) at increasing concentrations of acetylcholine (from 10(-7.5) to 10(-4....
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The role of electrical heterogeneity in development of cardiac arrhythmias is well recognized. The extent to which transmembrane action potential (TAP) heterogeneity contributes to the normal electrophysiology of well-oxygenated atria is not well defined. The principal objective of the present study was to define regional and transmural differences in characteristics of the TAP in isolated supe...
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ژورنال
عنوان ژورنال: Circulation Research
سال: 1991
ISSN: 0009-7330,1524-4571
DOI: 10.1161/01.res.69.4.1075