Cardiac Diagnostic Testing
Tilt Table Testing
Physicians use tilt table testing to determine the cause of syncope or fainting. During a tilt table test, the patient lies on a table that moves from a flat position parallel to the floor to an upright position nearly perpendicular to the floor. A tilt table test that induces an episode of syncope is considered positive. When syncope is not induced, the test is negative.
During a tilt table test, the patient lies on a table that moves from a flat position parallel to the floor to an upright position nearly perpendicular to the floor to help a physician determine the cause of syncope. A test that produces syncope is considered positive. A test that does not produce syncope is considered negative.
The physician may ask the patient to avoid certain medications, to refrain from eating or drinking after midnight the night before the test, or to bring a list of all the medications, vitamins, and supplements that he or she is taking to the test.
What to Expect
The patient lies flat on a table and is secured to it with straps. A nurse inserts an intravenous (IV) line to deliver medication and other fluids, as well as connects the patient to machines to monitor vital signs.
Because talking can alter blood pressure and electrocardiograph (ECG) measurements, the patient will be asked to lie still and remain quiet for the entire test. Baseline ECG and blood pressure readings are taken. After 20 to 30 minutes, the end of the table closest to the patient’s head is raised about 30 degrees for about 5 minutes while more ECG and blood pressure readings are taken. The table is then raised to between 60 and 80 degrees. This simulates standing up from a lying position. The person being tested may then remain in the upright position for 30 to 45 minutes.
If the test does not cause a syncopal episode after the 30- to 45-minute period, the physician may inject a medication called isoproterenol or may administer oral nitroglycerin to induce a syncopal event by simulating vasovagal syncope. The table will be raised again to between 60 and 80 degrees for 15 minutes, after which the table will be returned to the flat position.
The test takes about 90 minutes to 2 hours. The test results are generally available directly following the test.
Patients can resume normal activities immediately after a tilt table test. Nitroglycerin may cause headaches following the procedure.