Scintigraphy of the myocardium: a description of the procedure, contraindications and recommendations

In the world of high technologies, a period has already come when science and medicine go hand in hand and help each other improve. Basically, this is the new methods of diagnosing diseases, their detection at earlier times. Now everyone has a hearing about 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 - scintigraphy of the myocardium.

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 isotope data in the body in the process of fixing their radiation.

Perfusion myocardial scintigraphy is essentially the same study as described above, but using radioactive thallium. It is produced both with loading tests, and without them. It allows to establish precisely the focus of ischemia, which makes it irreplaceable in the diagnosis of coronary artery disease (ischemic heart disease).

To each according to the needs

Since 2007, scintigraphy has become widespread in the USA, Western Europe and a number of other developed countries. This medical service has already benefited more than fifteen million people. There it is a fairly routine procedure that does not take much time and effort.

In the post-Soviet space the situation is radically different. At the moment, about two hundred gamma cameras for scintigraphy are in operation in Russia (compared to the US thirteen thousand). And they are available only at the level of highly specialized assistance.

How it works?

Prepared for the procedure, a patient is injected into the vein with a drug-radio indicator, which contains a vector molecule and radioactive isotopes. Their work is interrelated, since the vector has a chemical tropism (location) to a particular organ or tissue of the human body. And the isotope emits gamma rays 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 scintigraphy show?

Thanks to this method of visualization, you can carefully review and evaluate the blood supply to the heart muscle, both in its entirety and in its individual parts. To detect areas with insufficient blood flow, and also to differentiate the places where the tissue of the heart has died, from those that can still be saved. In postinfarction patients, scars and areas of ischemia are easily identified. In addition, a specialist can predict by results of a 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 practically healthy people before important sports competitions and long surgical interventions under general anesthesia in order to exclude the risk of complications or injuries.

2. For the diagnosis of IHD, if there are all prerequisites for the formulation of such a diagnosis.

3. As a method of checking the effectiveness of the treatment: aortocoronary shunting, angioplasty, drug therapy.

4. To check the heart after a myocardial infarction (but not immediately after it, since repeated heart attacks may occur).

As a rule, this method allows you to accurately put a topical diagnosis and verify it.

Preparation of the patient for the procedure

Before each treatment or diagnostic procedure, the patient receives recommendations from the doctor, observance of which will help to conduct the study more fully and less traumatically for a person:

- The study is done on an empty stomach;
- One day before it can not drink coffee, Coca-Cola, tea, there is 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, because the baby can not be given breast for two days;
- Men should not use preparations to improve their erection the day before the test;
- Be sure to tell your doctor about the presence of bronchial asthma.

Preparations of radionuclides

Scintigraphy of the myocardium can not do without the use of radioactive drugs. There are now many types, depending on the purpose of the study:

- MIBI, or sestambi, is used to study the work of the heart, it 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.

- Pertechnics are used to study the thyroid gland.

- Iodine-123 is designed for visualization of the thyroid gland.

On the modern pharmacological market, drugs have already appeared, thanks to which it is possible to diagnose specific forms of oncological diseases. In the human body, these substances are administered intravenously, so you need to find out in advance whether the patient has any allergies.

Load tests

Stress-scintigraphy of the myocardium is carried out in the same way as an analogous study on electrocardiography. To create a stressful situation, the patient is offered to work out on the simulators (treadmill, bicycle). Indications for such a procedure are reliable changes on the ECG, complaints typical of coronary heart disease. One of the complexities of the procedure is obtaining a qualitative visualization of the left ventricle. The criteria for a positive sample are:

1. Fraction of ejection of the left ventricle is not more than 35%.
2. The increase in the ejection fraction during intensive work is more than 5%.
3. Reliable manifestation of breach of contractility.
4. Local disturbances of contractility of cardiomyocytes with minimal load.

Scintigraphy results

Scintigraphy of the myocardium allows obtaining several types of images of the heart muscle. Firstly, these are static, so-called static images. This is a two-dimensional (flat) mapping of the organ. Most often in this way, they examine the bones, endocrine glands, and so on.

Secondly, there are dynamic or moving images, allowing to evaluate the work of hollow organs. They are obtained as the result of addition of 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 damage.

Some specialists, when performing myocardial scintigraphy, also include Ophtex (single photon emission computed tomography) to obtain three-dimensional images of the organ under investigation. Often this is done with suspicion of a pathology of the heart or brain.

Is the method safe?

In Russia, only in exceptional cases, scintigraphy of the myocardium is performed. Contraindications to this study are simple: the 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 research 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, discomfort quickly passes and people return to normal life.

How to get to the study

Where can I make 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 identified by more accessible methods.

As already mentioned above, in the post-Soviet space the possibility to conduct such testing is available only in large cities. Myocardial scintigraphy in Moscow is conducted in several private clinics, as well as in the SPC of interventional cardiology, in the Research Institute of Gerontology of the Russian Ministry of Health, the Cardiovascular Surgery Center. AN Bakulev and in the department of radiation diagnostics of the Clinical Center of MMA named after. I. M. Sechenov.

The price policy in public and private medical institutions can differ, sometimes even very significantly. Therefore, it makes sense to carefully study the services that a specific hospital offers and then decide, arranges the requested amount for a study such as myocardial scintigraphy. The price in Moscow can 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 just for a simple study. But there are patients who need 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 state of health, and also helps to choose the optimal therapeutic tactics.

Myocardial scintigraphy is a relatively new, non-invasive, safe and painless way of examining the heart muscle. By combining the achievements of modern computer technology and discoveries in the field of radioactive substances, it became possible to diagnose ischemic lung disease at the earliest stages.