What is the tilt-table test?
The tilt-table test is a simple, inexpensive, and informative test that can help identify the causes of fainting. As its name implies, the tilt table test involves placing a patient on a table with a foot-support, then tilting the table upward. The tilt-table may start off in a horizontal position and be tilted by degrees to a completely vertical position. The patient's blood pressure, pulse, and symptoms are monitored throughout the test.
Why is the tilt-table test done?
The tilt-table test is designed to detect one of the most common causes of fainting or lightheadedness, a phenomenon known as postural hypotension (orthostatic hypotension). Tilt-table testing may be done when heart disease is not suspected of being responsible for an attack of fainting (syncope) or near-syncope.
What is postural hypotension (orthostatic hypotension)?
Postural hypotension is a common cause of an episode of temporary loss of consciousness or feelings of lightheadedness. Postural hypotension results from changing body position from a prone, supine, or sitting position to a more vertical position. Normally, blood tends to pool in the legs due to gravity when a person stands up, potentially reducing the amount of blood available to return to the heart. Nerves to the blood vessels in the legs normally act to compensate for this pooling by constricting, thus sending blood away from the leg veins and toward the heart. However, poor tone of the nerves to blood vessels in the legs can cause this mechanism to fail, resulting in a disproportionate distribution of blood to the legs, instead of returning to the circulation, so the brain receives less oxygen. As a result, a person feels lightheaded and may even faint.
What happens after the tilt-table test?
Depending on the presence or absence of signs and symptoms during the tilt-table test, persons with certain forms of temporary loss of consciousness may be admitted to the hospital for observation and further testing. The tilt-table test is also performed on stabilized patients who are in the hospital for evaluation of the cause of temporary loss of consciousness.
Does the tilt-table test hurt?
No. It is painless. However, patients may experience symptoms such as feeling lightheaded, nauseated, sweating, or weakness. Any symptoms recorded during the test can help the doctor to diagnose the cause of an episode of temporary loss of consciousness or lightheadedness.