Neurally mediated syncope
Related Experiment Video
Updated: Oct 10, 2026

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
1Department of Cardiology, Texas Heart Institute at St. Luke's Episcopal Hospital, Houston, USA.
Abstract:
Neurally mediated syncope is a disorder of the autonomic regulation of postural tone, which results in hypotension, bradycardia, and loss of consciousness. A wide variety of stimuli can trigger this reflex, the most common stimulus being orthostatic stress. Typically, a patient with neurally mediated syncope experiences nausea, lightheadedness, a feeling of warmth, and pallor before abruptly losing consciousness. If the cause of syncope is unclear, a stepwise approach is necessary to arrive at the diagnosis. The diagnosis of neurally mediated syncope can be confirmed by a head-up tilt-table test. Treatment options include behavioral modification and several pharmacologic therapies. For severe recurrent syncope unresponsive to conventional treatment, a pacemaker can be implanted.
Related Concept Videos
Chemical Synapses
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Chemical Synapses
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Disorders of the Autonomic Nervous System
Raynaud's disease, also known as Raynaud's phenomenon, is a...
Neural Regulation of Blood Pressure
Baroreceptor Reflex
Baroreceptors, located in the carotid sinuses and aortic arch, detect changes in blood pressure. When blood pressure rises, these stretch-sensitive receptors...
Narcolepsy
Major Somatic Sensory Pathways
