While it is not a secret that the heart is the core organ in your body that keeps you going. It is responsible to pump blood throughout your body through arteries, which bring blood to your heart. When arteries get squeezed or become too narrow, they make it hard for your heart to receive enough blood and oxygen it needs to pump and the risk of heart failure arises. When this defect persists, your doctor would suggest you a perfusion test. What is a perfusion defect? And why is it dangerous for your heart? The discussion focuses on everything that you might need to hear about perfusion defects and their side effects.
What is a perfusion defect?
A perfusion test is an imaging test that reveals the heart function to your doctor through images. These images are somewhere like ultrasound images that are made through sounds. A perfusion test tells your doctor how your heart is performing and whether it is getting enough blood.
This is also referred to as nuclear stress test or a myocardial perfusion imaging. This test might be recommended to you because of the following reasons;
- You might be experiencing chest pain due to the blocked or narrowed arteries that is commonly called ‘angina’.
- You might have gotten a heart arrest and your doctor wants to know the current status of your heart
- You might have had open-heart surgery – angiogram, a stent procedure, or bypass surgery and your cardiologist want to ensure that everything is working properly.
How is a myocardial perfusion scan performed?
Small patches of electrodes will be pasted to your chest, arms, and legs. These electrodes monitor a patient’s heart rate through long wires that are connected to a giant machine. If you have been a heart patient, you may have already seen these electrodes used for taking out Electrocardiogram (ECG) readings as well.
Your doctor may also make you wear cuffs on your wrists that will monitor your blood pressure. In a stress perfusion test, you may also need to run on a treadmill or exercise on a bicycle. At the end of the exercise, your doctor will use radioactive material and put it into your bloodstream called a tracer. It will easily get mixed in your blood and flows around your heart through arteries.
With this, your doctor will instruct you to lie down on a table. He will use a Gamma Camera (a special camera used to capture images of your heart). With the help of the radioactive material that was put into your blood a while ago, doctors will find out in which artery your heart is getting blood and which of them it is not.
If due to any reason (age or sickness) you become unable to excessively exercise for the test, you would be given medication that widens or dilates the coronary arteries. Once the medication starts working, your doctor will then give you a tracer to monitor the blood flow through the arteries.
After the tracer and camera monitoring, you will be put to rest for several hours. Once your body comes to normal, you will be taken to perform another scan with the Gamma camera so the doctors can identify the changes in your heart rate, blood pressure, arteries, and the function of the heart before and after exercise with quick and normal blood flow.
The entire perfusion scanning takes around four hours to be completed.
Preparing for the heart perfusion scan
Depending on the condition and age of the heart patient, you will be advised to perform a few things before your perfusion test.
- You may need to starve before taking the test. Your doctor may advise you to stop especially the foods with caffeine before the day of your perfusion test. In addition, you can also be restricted from having any solid food 6 hours before your test. However, you will be allowed to have water only.
- Also, you may need to stop some medications if you are taking some due to heart issues.
In the event that you breastfeed or are pregnant, make sure to inform your doctor about it before the test. Radiations from the Gamma camera or the radiology material, the tracer can transmit into a developing baby or into a breastfeeding infant through milk.
In addition, you must take all the information you need to know about the testing procedure and the duration of the perfusion scan beforehand. If you are physically fit, then you’ll be asked to exercise so wear comfortable shoes and clothes. If you are admitted to the hospital already you might be asked to wear a hospital gown if you are not already wearing it. It is also suggested not to wear any jewelry or metal items during the test, it may affect the results.
What are the risks involved in the perfusion scan?
During the perfusion test, depending on the health of the patient, there may be several risks that are attached to a cardiac perfusion test. It is also possible that you feel discomfort, which may include;
- Once you start exercising or are given medication, you could feel chest ache with the unusual heartbeat. If this happens, you should not hold back or bear with it while exercising and tell your doctor immediately.
- You may not get radiation from the tracer and feel adverse allergic reactions. People normally do not expose themselves to any reaction after the tracer is injected. But sensitive beings might get reactions either from the tracer or any other medication used during the process.
- The area of your body may get sore after you get a tracer just like any other area where you get a shot normally.
- Also, your heart may get stressed out after the shot or you may also begin to feel dizzy, shaky, nauseous, or short of breath during the exercise. Ensure that your doctor knows your condition.
There may be several questions that you want to ask your doctor before the test and also want to tell you about your condition and the drugs you are already using. Make sure to inform your doctor about allergies or sensitivity issues your body has. It’s better to take a family member or a caregiver along with you at the appointment before the test so he or she may help you remind you of the concerns you might have had in the past.
Certain factors may alter the result of the test which you should know to avoid;
- Using the medication containing theophylline and caffeine
- Intake of the medication containing caffeine and theophylline within the 48 hours of the test
- Using any form of illicit drugs or tobacco in any form such as smoking within 48 hours of the procedure
- Medications that slow down the heart rate
What happens after the myocardial perfusion scan?
Once the procedure has ended, move slowly from the table to avoid dizziness that will take you to the ground. This happens due to the flat laying on the procedure table for a long time. Sit for a few minutes before you stand, and gradually put the load on your feet.
After your procedure, you will be advised to drink plenty of drinks and water to empty your bladder after 48 hours of the test. This is essential to flush out the radioactive material from your body completely.
If not exercised, the place of the IV shot that you received would be monitored for signs of swell and redness. If in any event, you face complications after returning home from the procedure, consult your doctor for a quick healing process.
Depending on your condition after the test, your healthcare provider may also provide you with instructions and medication to adhere to for a few days or a week. If your myocardial procedure shows that you are at the risk of severe cardiac disease or there’s a risk of getting into one, your doctor will advise you for the next visit and guide you for the next procedure.
Frequently Asked Questions (FAQs)
1. What does reversible perfusion defect mean?
When stress is induced through perfusion in the region of abnormalities but they show normal behavior it is termed reversible perfusion defects. These regions are represented as essential ischemic tissues that reserve the blood flow.
2. What is reversible myocardial ischemia?
Reversible Myocardial Ischemia is one of the common diseases that usually cause atherosclerosis of the coronary artery, infrequent etiologies, and myocardial microcirculation disturbance. It happens essentially because of the insufficiency or perfusion in the myocardium.
3. What is Anteroapical?
Many doctors suggest that the Echocardiogram should be termed as ‘anteroseptal’ and must be called an anteroseptal infarction. Also, they suggest that the term anteroseptal describes the interior wall of the extreme MI.
4. What is reversible stress?
The definition that defines the reversible stress and the critical current strain limits are based on two factors;
- When releasing the applied strain and stress the Ic of the patient should be recovered to its original value.
- When the cyclic stress is applied Ic should maintain its original value.
5. Is ischemia applied to the heart reversible?
Ischemia is reversible if the affected issue recovers its blood flow. In other cases, ischemia is possibly reversible when the affected tissue resulted in death. Diseases like ischemia can also turn acute if a sudden reduction in blood flow occurs. In addition, chronic ischemia happens when there’s slow blood reduction.
6. What is a reversible apical defect?
A small apical defect refers to a condition where the tip of the heart does not get blood during the stress procedure and the affected area due to lack of blood flow is so small, that it reverses back to its original form. In this case, a patient should seek medical advice.
7. What is a reversible perfusion defect?
When stress is given to the patient, a small area of the heart does not get enough blood flow. A reversible defect indicates no reaction when on rest. Therefore, the process can be reversed as it was not always there, which shows a presence of a dead heart muscle under stress when compared to the previous MI results. This reversible defect shows artery blockage and results in heart failure if not treated timely.
8. How does perfusion defect in the apical anterior wall happen?
Given that we have discussed everything about heart failure and its causes due to perfusion, a perfusion defect in the apical anterior happens when a heart does not get enough oxygen due to apex creation in the anterior wall area. When this happens, the heart remains unable to maintain its tissues healthy, which often leads to serious health complications. If not treated timely, the unhealthy heart tissues lead to blockage of oxygen. Hence, sudden heart failure results in death.
To conclude, the article demonstrates the myocardial perfusion scientific techniques, systematic approach to reporting and interpreting the results, and clinical application of the procedure. It is essential to get familiar with the process for efficient and optimum results that would not cause lingering complications.