In the world of high technology, a period has already come when science and medicine go hand in hand and help each other improve. Basically, this consists of new methods for diagnosing diseases, identifying them at an earlier date. Now everyone has heard magnetic resonance imaging (MRI), nuclear magnetic resonance (NMR), computed tomography (CT), and even positron emission tomography (PET). But for a long time there is another way to visualize the internal environment of the human body - myocardial scintigraphy.
Definitions
Myocardial scintigraphy is a remote non-invasive
examination of the heart using radioactive particles. In fact, this is a record of the distribution of these isotopes in the body in the process of fixing their radiation.
Myocardial perfusion scintigraphy is essentially the same study as described above, but using radioactive thallium. It is made both with load tests, and without them. It allows you to accurately establish the focus of ischemia, which makes it indispensable in the diagnosis of coronary heart disease (coronary heart disease).
To each according to his needs.
Since 2007, scintigraphy has become widespread in the United States, Western Europe and several other developed countries. This medical service has been used by more than fifteen million people. There it is a fairly routine procedure, which does not take much time and effort.
In the post-Soviet space, the situation is fundamentally different. At the moment, about two hundred gamma-ray scintigraphy cameras are in operation in Russia (compared with the American thirteen thousand). And they are available only at the level of highly specialized assistance.
How it works?
A patient prepared for the procedure is injected into the vein with a radio indicator drug that contains a vector molecule and radioactive isotopes. Their work is interconnected, since the vector has a chemical tropism (location) to a specific organ or tissue of the human body. And the isotope emits gamma radiation into the space around it. Registration of this type of waves allows you to determine the best and worst blood supply.
What does scintigraphy show?
Thanks to this visualization method, you can carefully view and evaluate the blood supply to the heart muscle, as a whole, and individual parts. To detect areas with insufficient blood flow, as well as to differentiate places where the heart tissue has died, from those that can still be saved. In post-infarction patients, scars and areas of ischemia are easily detected. In addition, the specialist can predict from the results of the study what complications should be expected and how soon.
Indications for the procedure
Since this procedure is quite an expensive pleasure, its purpose should be justified. It is carried out in the following cases:
1. For healthy people, before important sporting events and lengthy surgical interventions under general anesthesia to eliminate the risk of complications or injuries.
2. For the diagnosis of coronary heart disease, if there are all prerequisites for making such a diagnosis.
3. As a method of checking the effectiveness of the treatment: coronary artery bypass grafting, angioplasty, drug therapy.
4. To check the work of the heart after a myocardial infarction (but not immediately after it, as repeated heart attacks can occur).
As a rule, this method allows you to accurately make a topical diagnosis and verify it.
Preparing the patient for the procedure
Before each treatment or diagnostic procedure, the patient receives recommendations from the doctor, compliance with which will help to conduct a study more fully and less traumatic for a person:
- the study is done on an empty stomach;
- the day before him you can’t drink coffee, Coca-Cola, tea, eat chocolate;
- you need to stop taking medications that stabilize the heart;
- make an ultrasound to exclude pregnancy, and nursing mothers should prepare milk in advance, since the baby will not be able to give breasts for two days;
- Men one day before the study should not use drugs to improve erection;
- Be sure to warn your doctor about your bronchial asthma.
Radionuclide preparations
Myocardial scintigraphy is not complete without the use of radioactive drugs. There are many types of them now, depending on the purpose of the study:
- MIBI, or sestambi, is used to study the work of the heart, has tropism to the heart muscle.
- Mono- and bisphosphonates have an affinity for bone tissue, are used to diagnose cancer and their complications, as well as injuries.
- Diethylenetriaminepentaacetic acid reveals kidney pathology.
- Pertechnates are used to examine the thyroid gland.
- Iodine-123 is intended for imaging of the thyroid gland.
Preparations have already appeared on the modern pharmacological market, thanks to which it is possible to diagnose specific forms of cancer. These substances are administered intravenously into the human body, so you need to find out in advance whether the patient has allergies.
Stress test
Myocardial stress scintigraphy is carried out in the same way as a similar study on electrocardiography. To create a stressful situation, the patient is offered to work out on simulators (treadmill, bicycle). Indications for such a procedure are reliable changes on the ECG, complaints characteristic of coronary heart disease. One of the difficult moments of the procedure is to obtain high-quality visualization of the left ventricle. The criteria for a positive test are:
- Left ventricular ejection fraction is not more than 35%.
- The increase in ejection fraction during intensive work by more than 5%.
- A reliable manifestation of a violation of contractility.
- Local disturbances in the contractility of cardiomyocytes with minimal load.
Scintigraphy Results
Myocardial scintigraphy allows you to get several types of images of the heart muscle. Firstly, these are still, so-called static, shots. This is a two-dimensional (flat) image of an organ. Most often in this way they examine bones, endocrine glands, etc.
Secondly, there are dynamic or moving images that allow you to evaluate the work of hollow organs. They are obtained as a result of combining several still pictures. They are used to examine the liver, kidneys, heart, blood vessels.
The third type of registration of the study is ECG synchronization. Additional removal of the cardiogram allows you to compare the function and topography of organ damage.
Some experts, performing myocardial scintigraphy, also connect SPECT (single-photon emission computed tomography) to obtain three-dimensional images of the organ under investigation. Often this is done if a pathology of the heart or brain is suspected.
Is the method safe?
In Russia only in exceptional cases myocardial scintigraphy is performed. Contraindications to this study are simple: lack of individual sensitivity to a radioisotope drug. In addition, the procedure is contraindicated:
- pregnant and lactating mothers;
- people with severe diseases of other organs and systems (this can create problems during the study using the load);
- patients with sepsis and fever;
- with myocarditis, the presence of heart defects and after a recent heart attack.
The method itself is painless and almost harmless. Sometimes patients experience side effects from medications or physical exertion, but, as a rule, the discomfort quickly passes, and people return to normal life.
How to get to the study
Where to do myocardial scintigraphy? First of all, it is necessary to undergo an examination in a clinic or in a therapeutic hospital to determine if there is a need for such an expensive study. Many heart diseases can be detected by more accessible methods.
As mentioned above, in the post-Soviet space, the opportunity to conduct such testing is available only in large cities. Myocardial scintigraphy in Moscow is carried out in several private clinics, as well as in the Scientific and Practical Center for Interventional Cardiology, in the Research Institute of Gerontology of the Ministry of Health of the Russian Federation, and the Scientific Center for Cardiovascular Surgery. A. N. Bakuleva and in the department of radiation diagnostics of the Clinical Center MMA named after I.M.Sechenova.
Pricing policies in public and private hospitals can vary, sometimes even quite significantly. Therefore, it makes sense to carefully study the services that a particular hospital offers and then it is already up to you to decide on the requested amount for such a study as myocardial scintigraphy. The price in Moscow may vary depending on the volume of the procedure and the venue. The cost is somewhere in the region between seven and eight thousand rubles. This is for simple research only. But there are patients who require myocardial scintigraphy with exercise. Its price will be at least twice as high. From fifteen thousand rubles, respectively. However, this method gives the doctor a more complete picture of the patient’s health status, and also helps to choose the optimal therapeutic tactics.
Myocardial scintigraphy is a relatively new, non-invasive, safe and painless way to examine the heart muscle. By combining the achievements of modern computer technology and discoveries in the field of radioactive substances, it has become possible to diagnose coronary artery disease in the very early stages.