From the Research
Introduction to Abnormal Tilt Table Test Results
Abnormal tilt table test results can indicate various autonomic disorders, including orthostatic hypotension, postural orthostatic tachycardia syndrome, and neurally mediated syncope 1, 2. The diagnosis and recommended next steps for a patient with abnormal tilt table test results depend on the specific findings and the patient's clinical presentation.
Diagnosis
The tilt table test is used to assess orthostatic hypotension, chronic orthostatic intolerance, and unexplained syncope 1. The test can help distinguish neurogenic from non-neurogenic orthostatic hypotension, identify failure of the sympathetic noradrenergic system in autonomic neuropathies and ganglionopathies, and assess baroreflex-sympathoneural function in α-synucleinopathies. The test can also provide objective data related to the patient's symptoms, diagnose postural tachycardia syndrome, and distinguish it from other causes of tachycardia.
Recommended Next Steps
The recommended next steps for a patient with abnormal tilt table test results include:
- Further evaluation to determine the underlying cause of the abnormal results, such as autonomic function tests or other provocative cardiovascular autonomic tests 2
- Treatment of the underlying condition, such as medication to manage orthostatic hypotension or postural orthostatic tachycardia syndrome
- Patient education on recognizing hypotensive symptoms and performing physical counter maneuvers to prevent syncope 2
- Consideration of implantable loop recorders to document cardioinhibitory reflex syncope, especially in patients over 45 years of age 3
Differential Diagnosis
The differential diagnosis for abnormal tilt table test results includes:
- Orthostatic hypotension
- Postural orthostatic tachycardia syndrome
- Neurally mediated syncope
- Psychogenic pseudosyncope
- Other causes of tachycardia or hypotension
Caveats
The interpretation of tilt table test results must be done in the context of the patient's clinical presentation 1. The test is not useful for assessing the response to treatment, and other tests, such as implantable loop recorders, may be needed to document cardioinhibitory reflex syncope 3.
Treatment
Treatment for abnormal tilt table test results depends on the underlying condition. Medications, such as fludrocortisone or midodrine, may be used to manage orthostatic hypotension, while beta blockers or ivabradine may be used to manage postural orthostatic tachycardia syndrome. Patient education on recognizing hypotensive symptoms and performing physical counter maneuvers is also important.
Conclusion
Abnormal tilt table test results can indicate various autonomic disorders, and the diagnosis and recommended next steps depend on the specific findings and the patient's clinical presentation. Further evaluation, treatment, and patient education are essential for managing these conditions, and the interpretation of tilt table test results must be done in the context of the patient's clinical presentation 1, 2, 3, 4, 5.