| Where It's Done | Who Does It | How Long It Takes | Discomfort/Pain |
| Hospital outpatient department. | Doctor and technician. | 20-25 minutes. | Possible dizziness, nausea, and perhaps vomiting. |
| Results Ready When | Special Equipment | Risks/Complications | Average Cost |
| Immediately. | An examining table that tilts at various angles. | Test may provoke a heart attack. | $$ |
None.
PurposeTo investigate fainting episodes (syncope), many of which involve an abnormal reflex that causes a fall in blood pressure and a slow heart rate but not an arrhythmia; this condition is called neurocardiogenic syncope.
How it worksAbruptly tilting your position so blood drains from your head usually provokes fainting and a fall in blood pressure and heart rate if you have neurocardiographic syncope. Medication may also be used to provoke the response.
Preparation- An intravenous line is started.
- You are monitored with ECG leads and a blood pressure cuff. A defibrillator and other emergency measures are available.
- After being strapped in place with loosely fitting belts on a tilt table, you lie flat for 15 minutes and are then abruptly tilted to an 80-degree upright position.
- If no symptoms occur, the tilt may be repeated after the administration of a medication.
- An abnormal response involves a fall in blood pressure, slowed heart rate, and other symptoms of fainting or near-fainting.
After a short observation period, you may resume normal activities.
Factors affecting resultsOther medications may affect results.
InterpretationA physician trained in electrophysiology studies and reports the response.
AdvantagesThe test may provide the best information concerning fainting due to an abnormal reflex.
DisadvantagesIt should be done only in a hospital or facility where emergency resources are available.
The next stepIf the test is positive, the abnormal reflex is present, and specific medication will be started.
Several imaging tests are under investigation at Yale and other leading medical centers as diagnostic tools in heart disease. These include:
- Computed Tomography (CT) Scans. This technique, which uses multiple X-ray images to create a cross-sectional view of an internal organ, is being used to detect calcifications in the coronary arteries. Such calcium deposits are an indication of atherosclerosis--the buildup of fatty deposits in the artery walls. Although CT scanning can detect early atherosclerosis, before symptoms such as shortness of breath or chest pains develop, it does not necessarily indicate the degree of vessel narrowing. Thus its present usefulness is mostly as a screening tool, although this may change as more experience is gained in its applications in heart disease. It also should be noted that CT scanning for this purpose is not covered by insurance.
- Magnetic Resonance Imaging (MRI). This imaging study, which uses powerful magnetic fields and radio waves to create images of internal organs, is under investigation as a tool in assessing cardiac structures and function. Among imaging studies, MRI provides the best anatomical details and it is of special value in assessing aortic and pericardial diseases and complex congenital heart disorders. It is also a tool that can be used for noninvasive coronary angiography, and to study myocardial perfusion and the functioning of the left and right ventricles, the heart's pumping chambers.
