A tilt table test is used to evaluate the cause of unexplained fainting.
Your doctor might recommend a tilt table test if you have repeated, unexplained episodes of lightheadedness, dizziness or fainting. The test can help determine if the cause is related to your heart rate or blood pressure.
In a tilt table test, you lie on a table that adjusts your body position from horizontal to vertical to simulate standing up. The test can tell your doctor if faulty brain signals are causing low blood pressure.
Your doctor might recommend a tilt table test to try to trigger your signs and symptoms — lightheadedness, dizziness or fainting — while your heart rate and blood pressure are being monitored.
Your nervous system controls your heart rate and blood pressure. It may suddenly lower your heart rate and blood pressure for a short time when you're moved to an upright position during the tilt table test. As a result, less blood flows to your brain, possibly causing you to faint.
A tilt table test is generally safe, and complications are rare. But, as with any medical procedure, it does carry some risk.
Potential complications include:
These complications usually go away when the table is returned to a horizontal position.
You might be asked not to eat or drink for two hours or more before a tilt table test. You can take your medications as usual, unless your doctor tells you otherwise.
To prepare you for the test, a member of your health care team will:
Your heart rate and blood pressure will be monitored in each position to evaluate your body's cardiovascular response to the change in position.
If you faint while vertical, the table will be returned to a horizontal position immediately and you'll be monitored. Most people regain consciousness almost immediately.
In some cases, if blood pressure and heart rate changes indicate you are about to faint, the table is returned to a horizontal position so that you don't lose consciousness.
When the test is complete, you can return to your normal activities.
The results of a tilt table test are based on whether you faint during the test and what happens to your blood pressure and heart rate.
The result is positive if your blood pressure decreases and you feel dizziness or faint during the test.
The result is negative if your heart rate increases only slightly, your blood pressure doesn't drop significantly, and you don't have signs or symptoms of fainting.
Depending on the results, your doctor might recommend additional tests to exclude other causes of fainting.