Effects of Cardiac Sympathetic Nerve Stimulation on Conduction
نویسنده
چکیده
• There is general agreement that sympathetic agents enhance impulse transmission through the A-V node, but reports differ concerning their influence on specialized conduction tissue and ventricular muscle.-Recently several investigators" have suggested that catecholamines may result in a more synchronous contraction of the heart, resulting possibly from a change in the sequence of ventricular activation. In the experiments described in this report, we have examined the effects of direct cardiac sympathetic nerve stimulation on the manner of ventricular activation, on conduction in ventricular muscle and Purkinje tissue, and on A-V nodal transmission. A preliminary report of these observations has appeared elsewhere.
منابع مشابه
Sympathetic and periodic vagal influences on antegrade and retrograde conduction through the canine atrioventricular node.
Concurrent stimulation of the parasympathetic and sympathetic branches of the autonomic nervous system causes a diminished sympathetic response at high levels of vagal activity. This "accentuated antagonism" has been demonstrated for cardiac chronotropic, inotropic, and dromotropic responses. The effect on conduction was demonstrated with tonic stimulation of the vagus nerve. However, normally ...
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