A tilt table test is used to evaluate the cause of unexplained fainting.
A health care provider might recommend a tilt table test to evaluate repeated, unexplained episodes of lightheadedness, dizziness or fainting. The test can help determine if the cause is related to heart rate or blood pressure.
Why it's done
A health care provider might recommend a tilt table test to try to trigger signs and symptoms — lightheadedness, dizziness or fainting — while monitoring heart rate and blood pressure.
The nervous system controls heart rate and blood pressure. It may suddenly lower the heart rate and blood pressure for a short time when moving to an upright position during the tilt table test. As a result, less blood flows to the brain, possibly causing fainting.
A tilt table test is generally safe. Complications are rare. But, as with any medical procedure, it does carry some risk.
Potential complications of a tilt table test include:
- Weakness that can last several hours
- Continued low blood pressure after the test
These complications usually go away when the table is returned to a horizontal position.
How you prepare
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 health care provider tells you otherwise.
What you can expect
Before the test, your health care provider:
- Has you lie flat on a table that has a footboard and places straps around you to hold you in place.
- Places sticky patches (electrodes) on your chest, legs and arms. Wires connect the electrodes to an electrocardiogram machine that monitors your heart rate.
- Places a blood pressure monitor or cuff on your finger, on your arm or on both to check your blood pressure during the test.
- Places an IV line into a vein in your arm for delivering drugs, if needed.
During a tilt table test
- You lie flat on your back on the motorized table for about five minutes.
- You're then moved to a nearly vertical position, where you'll remain from 5 to 45 minutes, depending on the reason for the test. While in this position, stay as still as possible and report signs and symptoms such as nausea, sweating, lightheadedness or irregular heartbeats.
- If you don't faint or have other symptoms after 45 minutes, you might receive the drug isoproterenol (Isuprel) through an IV line in your arm. The drug might prompt the reflex that causes you to faint.
- You then remain in the upright position for another 15 to 20 minutes.
Your heart rate and blood pressure will be monitored in each position to evaluate your body's response to the change in position.
After a tilt table test
If you faint while upright, the table will be returned to a horizontal position immediately and you'll be monitored. Most people regain consciousness almost immediately.
When the test is complete, you can return to your regular 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.
- Positive result. Blood pressure decreases, causing dizziness or fainting during the test.
- Negative result. Heart rate increases only slightly, blood pressure doesn't drop significantly, and there are no signs or symptoms of fainting.
Depending on the results, your care provider might recommend more tests to rule out other causes of fainting.