What is hemodynamic monitoring?
Hemodynamic monitoring is a procedure that checks your blood circulation and evaluates how well your heart is working. It’s also known as a hemodynamic tilt test or a technetium (pronounced tek-nee-see-um) hemodynamic test. It uses nuclear imaging.
Why is hemodynamic monitoring used?
If you’ve been fainting (syncope), your provider will use the information from your test to find the cause of your syncope or circulation disorder. The test results will also help determine the best plan of care for you.
You may pass out when you have:
- A temporary decline in blood flow to your brain.
- A sudden drop in your blood pressure or heart rate.
- Changes in blood volume or distribution.
Many people who faint have a medical condition related to their heart, nervous system or blood flow to their brain.
How do I prepare for hemodynamic monitoring?
Because you can’t have the test if you’re pregnant or breastfeeding (chestfeeding), you may need to take a pregnancy test for your safety.
Don’t eat or drink anything for four hours before your test. This includes gum and candy. If you need to take medicines, take them with a small sip of water.
Don’t eat or drink anything that contains caffeine on the day of your test. This includes anything labeled “caffeine-free” or “decaffeinated.” These products may contain small amounts of caffeine.
If you have diabetes, ask for a 12:30 p.m. appointment time so you can eat a light breakfast before 8:30 a.m.
Don’t take strong diuretics (“water pills”) or laxatives before the test. It’s best if you don’t need to get up during your test.
You can take all other medications as you normally do. Ask your provider or pharmacist if any of your medications contain caffeine and if you should take these on the day of your test. Don’t stop taking any medication without asking your provider.
What should I expect on the date of the test?
Wear comfortable clothes and shoes. You’ll undress from the waist up and wear a hospital gown during hemodynamic monitoring. Don’t wear jewelry (including wedding rings) or bring valuables.
Bring the following to your appointment:
- Your recent medical history and physical exam report.
- Any available medical records related to your health problems.
- A list of all medications and supplements you take (including how much you take).
- A list of all your allergies.
How long does a hemodynamic assessment take?
The test takes almost three hours to complete. Plan on being at the hospital for up to three hours for your appointment.
Will I be awake during the test?
Yes. You’ll be awake during the test. Your provider will do everything they can to make you comfortable. Staying as still and quiet as you can allows your provider to get the best images possible.
What is used for hemodynamic monitoring?
Your provider will use:
- EKG Monitoring: Electrodes (small, sticky patches) on your chest send information to an electrocardiograph (EKG/ECG) monitor. This machine records your heart’s electrical activity as a graph on a moving strip of paper. The EKG shows your heart rate and rhythm during the test.
- Blood Pressure Monitoring: A blood pressure cuff on your arm checks your blood pressure at different times during the test.
- Hemodynamic Echo: Before you start your test, you‘ll have an echocardiogram (after you’ve rested for 20 minutes). The test takes about 20 minutes and creates detailed pictures of your heart. It also measures how much blood your heart pumps out (cardiac output). Your provider will measure your cardiac output again during the test and compare that reading to the first measurement.
- Nuclear Medicine Imaging: Your provider uses a gamma camera to take pictures during the test. The camera detects gamma rays from a radioactive isotope (tracer). Images from this camera give your provider information about how well your heart works and your blood circulation. It can tell them how much blood your heart pumps and how fast your blood moves.
What should I expect during hemodynamic monitoring?
During your hemodynamic monitoring test:
- You’ll lie on your back on an exam table.
- Your healthcare provider will explain the procedure in detail and answer any questions you may have.
- You’ll get an IV so you can receive a radioactive isotope.
- Your provider will inject the tracer into your IV before taking each set of images. You also may get other medications through the IV during the test.
- Your provider will position the gamma camera over your chest. You’ll need to stay still while it takes images. The camera may rotate around you.
How will I feel during the test?
You may not have any symptoms during a hemodynamic monitoring test. However, it’s not unusual to feel light-headed, nauseous or have heart palpitations.
You may feel a chill going up your arm when the radioactive agent goes through your IV. You may also notice a metallic taste in your mouth or a strange smell in your nose. These don’t last long.
It’s important to tell your provider how you feel throughout your test. They can make changes between sets of images to help you feel more comfortable. Your symptoms, along with your test information, will help your provider determine the cause of your condition.
How does hemodynamic monitoring work?
A gamma camera detects the radiation from the tracer you get in your IV. A computer creates a series of images from this information. You may have up to three sets of images (two while lying flat and one while sitting).
What should I expect after hemodynamic monitoring?
After your hemodynamic assessment:
- You’ll stay at the hospital until any symptoms you had are gone.
- Some of the tracer used in the test will leave your body through your pee. The rest breaks down naturally. If you want, you can drink extra fluids to help flush out the tracer.
- You’ll get a U.S. Department of Homeland Security card to carry when traveling for one week after the test. The isotope used during the test may cause an alarm to sound when you go through airport security.
- Most people go home right after the test. You may want to have a driver with you in case you have severe symptoms.
What are the risks and side effects of a hemodynamic assessment?
You may have some bruising, redness or swelling in the area where you got your IV. This is common. You may also have pain or discomfort when your provider inserts your IV.
The radioactive isotope isn’t a dye and doesn’t cause any allergic side effects. The amount of radiation used in the test is very low. It’s about the same amount of radiation as you get during a chest X-ray.
Results and Follow-Up
What type of results do you get and what do the results mean?
Your provider’s report will note if your results were normal or abnormal.
They can also tell you if you had:
- An abnormal heart rhythm.
- Changes in blood pressure.
- An issue (such as coronary artery disease) that they saw, where it’s happening, how severe it is and which blood vessels it affects.
- Ischemia (reduced blood flow).
- Infarction (tissue death from a lack of blood and oxygen).
When should I know the results of the test?
Your provider should get the test results within 10 to 14 days.
They’ll use the test results to create your plan of care. You may need to take new or different medications. Also, they may refer you to other providers to help manage your care.
Your provider may order other tests, depending on the results of your hemodynamic assessment.
A note from Cleveland Clinic
Hemodynamic monitoring can help you find out why you’re having symptoms, such as fainting. Your provider can answer any questions you have about your test. The only pain you may feel during your test is from getting an IV. Your test results will help your provider decide what kind of treatment is best for you.
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