In the world of high technologies, the period has already begun when science and medicine go hand in hand and help each other to improve. This mainly consists in new methods for diagnosing diseases, their detection at an earlier date. Now everyone is talking about magnetic resonance imaging (MRI), nuclear magnetic resonance (NMR), computed tomography (CT) and even positron emission tomography (PET). But for a long time there has been another way to visualize the internal environment of the human body - myocardial scintigraphy.
Definitions
Myocardial scintigraphy is a remote non-invasive study 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 produced both with load tests and without them. It allows you to accurately determine the focus of ischemia, which makes it indispensable in the diagnosis of coronary artery disease (coronary heart disease).
To each according to his needs
Since 2007 in the USA,Western Europe and a number of other developed countries scintigraphy has become widespread. More than fifteen million people have already used this medical service. There it is a rather routine procedure that does not take much time and effort.
In the post-Soviet space, the situation is fundamentally different. At the moment, there are about two hundred gamma cameras for scintigraphy in operation in Russia (compared to the American thirteen thousand). And they are available only at the level of highly specialized care.
How does it work?
A patient prepared for the procedure is injected into a vein with a radiotracer drug that contains a vector molecule and radioactive isotopes. Their work is interconnected, since the vector has a chemical affinity (disposition) 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 places of the best and worst blood supply.
What does a scintigraphy show?
Thanks to this imaging method, you can carefully view and evaluate the blood supply to the heart muscle, both as a whole and in individual parts. Find areas with insufficient blood flow, as well as differentiate places where heart tissue has died from those that can still be saved. In postinfarction patients, scars and areas of ischemia are easily detected. In addition, the specialist can predict, based on the results of the study, whichcomplications should be expected and how soon.
Indications for the procedure
Since this procedure is quite an expensive pleasure, its purpose must be justified. It is carried out in the following cases:
1. For apparently he althy people before important sports competitions and long-term surgical interventions under general anesthesia to eliminate the risk of complications or injuries.
2. For the diagnosis of coronary artery disease, if there are all the prerequisites for making such a diagnosis.
3. As a method of testing 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 may 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 medical or diagnostic procedure, the patient receives recommendations from the doctor, the observance of which will help to conduct the study more fully and less traumatically for the person:
- the study is done on an empty stomach;
- the day before it you can not drink coffee, Coca-Cola, tea, eat chocolate;
- you need to stop taking medications that stabilize the heart;
- do an ultrasound to rule out pregnancy, and nursing mothers should prepare milk in advance, as the babyit will not be possible to breastfeed for two days;
- men the day before the study should not use drugs to improve erection;- be sure to tell your doctor if you have bronchial asthma.
Radionuclide preparations
Myocardial scintigraphy is not complete without the use of radioactive drugs. There are now many types of them, depending on the purpose of the study:
- MIBI, or sestamibi, is used to study the work of the heart, has a tropism for the heart muscle.
- Mono- and bisphosphonates have an affinity for bone tissue, are used to diagnose cancer and its complications, as well as injuries.
- Diethylenetriaminepentaacetic acid detects kidney pathology.
- Pertechnates are used for thyroid testing.
- Iodine-123 is for thyroid imaging.
Drugs have already appeared on the modern pharmacological market, thanks to which it is possible to diagnose specific forms of oncological diseases. These substances are injected into the human body intravenously, so you need to find out in advance if the patient has allergies.
Stress tests
Myocardial stress scintigraphy is performed 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). The indications for such a procedure are reliable changes in the ECG, complaints characteristic of coronary heart disease. One ofThe most difficult part of the procedure is obtaining high-quality visualization of the left ventricle. The criteria for a positive sample are:
- Left ventricular ejection fraction not more than 35%.
- Increased ejection fraction during hard work by more than 5%.
- Reliable manifestation of impaired contractility.
- Local disorders of cardiomyocyte contractility at minimal load.
Scintigraphy results
Myocardial scintigraphy provides several types of images of the heart muscle. First, these are still, so-called static, pictures. This is a two-dimensional (flat) representation of an organ. Most often, bones, endocrine glands, etc. are examined in this way.
Secondly, there are dynamic or moving images that allow you to evaluate the work of hollow organs. They are obtained as a result of adding 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 the organ lesion.
Some specialists, when conducting myocardial scintigraphy, also connect SPECT (single photon emission computed tomography) to obtain three-dimensional images of the organ under study. This is often done when a pathology of the heart or brain is suspected.
Is the method safe?
In Russia, scintigraphy is performed only in exceptional casesmyocardium. Contraindications to this study are simple: lack of individual sensitivity to the radioisotope preparation. 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 practically harmless. Occasionally, patients experience side effects from medications or exercise, but the discomfort usually resolves quickly 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 polyclinic or in a therapeutic hospital to determine whether there is a need for such an expensive study. Many heart diseases can be detected with 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, at the Russian Research Institute of Gerontology of the Ministry of He alth and Social Development of the Russian Federation, the N. N. A. N. Bakulev and in the Department of Radiation Diagnostics of the Clinical Center of the MMA named after. I. M. Sechenov.
Price policy in public and private medical institutions may differ, sometimes even veryessential. Therefore, it makes sense to carefully study the services that a particular hospital offers and then decide whether the requested amount suits you for such a study as myocardial scintigraphy. The price in Moscow may vary depending on the scope of the procedure and the location of the procedure. The cost is somewhere in the region between seven and eight thousand rubles. This is just for simple research. But there are patients who require myocardial scintigraphy with a load. 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 he alth status, and also helps to choose the best treatment 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 pulmonary disease at the earliest stages.
