Tilt table and active stand tests
Dizziness, fainting and rapid heart beats have many different causes. If autonomic dysfunction is suspected, tests may be done to examine how heart rate, blood pressure and symptoms change with body positioning.
Tilt table testing
The classic tilt table test is a diagnostic procedure used to examine how heart rate and blood pressure change with position. Tilt is used for patients experiencing unexplained fainting (syncope), but sometimes also for less dramatic symptoms such as dizziness and subjective feelings of heart racing, if these seem to be related to posture (i.e. worse on standing than on sitting or lying down).
The test assesses how the autonomic nervous system, which governs heart rate and blood pressure, responds to changes in body position, potentially helping to identify diagnoses such as orthostatic hypotension, postural tachycardia syndrome (PoTS), or vasovagal syncope (also called “reflex syncope”). The test is particularly useful for patients with reflex syncope as the sequence of heart rate and blood pressure changes seen during the test can help guide specific treatments.
During the test, patients lie on a special table that tilts from a horizontal to a nearly vertical position. Monitors continuously record the heart rate and blood pressure throughout the procedure, usually beat-to-beat. Sometimes other recordings are made, too, including a continuous ECG (heart rhythm) monitor or EEG (brain activity) monitoring.
Initially the patient rests flat for a baseline assessment to allow heart rate and blood pressure to stabilise. The table is then tilted to 60 degrees, which is a particularly stimulating and noxious position for some susceptible patients. The patient is held at this position for up to 40 minutes depending on the protocol being used. Sometimes nitroglycerin is administered to try to provoke an attack of fainting if the position alone fails to do this.
As the test is designed to trigger symptoms that are not very pleasant, it can be a little stressful. It is important to remember that the test is being carried out under very controlled conditions with experienced staff on standby should the patient pass out.
Results from the test help tailor treatment plans. Understanding the specific dysfunction ensures precise and effective management, improving symptoms and quality of life.
Active stand test
Active stand testing is a simple, non-invasive diagnostic tool used to evaluate cardiovascular autonomic dysfunction. This test helps identify conditions such as orthostatic hypotension (OH), postural tachycardia syndrome (PoTS), inappropriate sinus tachycardia, and delayed blood pressure recovery, which can cause symptoms such as dizziness, fainting, or rapid heart rate.
During the test, the patient lies flat for several minutes while the heart rate and blood pressure are recorded to establish a baseline. Then they stand, or lean against a wall, remaining stationary for 10 to 15 minutes, depending on the protocol being used.
Most active stand tests are performed with only intermittent monitoring of the heart rate and blood pressure, but more accurate insights into physiological disturbances can be gained by using continuous beat-to-beat heart rate and blood pressure monitoring as is used for tilt testing. Kent and London Cardiology only works with hospitals using continuous physiological monitoring.
Results from active stand testing guide tailored treatments, and can lead to patients understanding the cause of their symptoms more fully, enabling them to take control of managing their condition.