PART 2: Cardinal Manifestations and Presentation of Diseases
SECTION 3 Nervous System Dysfunction
20 Syncope
 | Figure 20-1 The Baroreflex. A decrease in arterial pressure unloads the baroreceptors—the terminals of afferent fibers of the glossopharyngeal and vagus nerves—that are situated in the carotid sinus and aortic arch. This leads to a reduction in the afferent impulses that are relayed from these mechanoreceptors through... |
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 | Figure 20-2 A. The paroxysmal hypotensive-bradycardic response that is characteristic of neurally mediated syncope. Noninvasive beat-to-beat blood pressure and heart rate are shown over 5 minutes (from 60 to 360 seconds) of an upright tilt on a tilt table. |
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 | Figure 20-3 A. The gradual fall in blood pressure without a compensatory heart rate increase that is characteristic of orthostatic hypotension due to autonomic failure. Blood pressure and heart rate are shown over 5 minutes (from 60 to 360 seconds) of an upright tilt on a tilt table. |
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