Modern methods for diagnosing heart disease have reached unprecedented efficiency. In addition to the standard cardiogram, there is a whole list of ways to detect pathologies. One of the most effective modern methods is stress echocardiography with physical activity. Who is diagnosed? What are the prerequisites for the procedure? What is stress echocardiography aimed at? We will try to answer these and other questions.
What is a stress echocardiogram?
Stress ECG is a modern method for studying ischemic diseases, which is characterized by creating a load on the patient's body, which leads to an increase in the frequency of contractions of the heart muscle.
Local contractility disorders of individual tissue sections are a direct sign of the development of pathology. In most cases fixminimal deviations in the work of the heart muscle during a conventional electrocardiogram in a calm state is simply impossible. On the contrary, stress echocardiography allows to determine with high accuracy the presence of ischemic pathologies in the early stages of development.
A Brief History
The principles of the diagnostic technique were described in the medical literature by American researchers of coronary heart disease R. Rost and L. Vann in 1979. A few years later, the first ever stress echocardiography was performed on a horizontal bicycle ergometer. Subsequently, the co-authors of the scientific treatise L. Erbel and S. Berte, who joined the project, proposed replacing physical activity with the use of pharmacological and electrostimulating methods of influencing the cardiovascular system of patients during research.
In domestic practice, M. Alekhin was engaged in the improvement of the diagnostic method. "Stress echocardiography" (PDF-format) is a popular guide today. In this scientific work, the researcher reflected all the experience of diagnostics accumulated over many years. Here, the specialist managed to display the evidence base, which confirms the feasibility of the procedure in order to study cardiac ischemia and other diseases of the cardiovascular system.
Diagnostic principle
Stress echocardiography is based on the premise thatwith the formation of ischemia in the cardiac myocardium, the ability of the left ventricle to contractility in the area of the coronary artery worsens. A prerequisite for the development of pathology are violations of venous blood flow.
Stress echocardiography allows you to record the reaction of individual zones of the left ventricular myocardium to increased, sharp loads that are exerted on the patient's body. In addition to bringing the cardiovascular system into a state of overstrain during the study, the visualization of the performance of the heart muscle in the form of a graph is carried out in parallel, which makes the method an effective tool for complex diagnostics.
Preparing for the study
In preparation for the diagnosis, the patient is prescribed pharmacological preparations containing nitrates, which can slow down the heart rate and lower blood pressure. Thus, the heart muscle is protected from the active production of adrenaline during stressful loads, which can cause a general deterioration in the patient's condition.
On the day of the study, the patient is allowed to use nitroglycerin, with the help of which probable angina attacks are stopped. However, the patient must warn the cardiologist in advance about taking funds containing a substance.
Recommendations for stress echocardiography include not eating approximately 6 hours before the diagnosis. Before the study, limited fluid intake is also encouraged. The day before the diagnosis, the patient must give up caffeine, because ita tonic effect on the body can affect the accuracy of the results. Smoking is prohibited immediately before the procedure.
Indications for diagnostics
In what cases is this type of diagnostic used? Stress echocardiography is prescribed for patients:
- if painless myocardial ischemia is suspected;
- need for coronary artery assessment;
- study of myocardial tissue viability;
- past myocardial infarction, chronic forms of coronary heart disease;
- need for surgical intervention aimed at bypass, stenting, angioplasty of the coronary arteries;
- necessity to evaluate the results of drug therapy;
- forming a prognosis for the development of cardiac pathologies;
- assessing the likelihood of complications after treatment of cardiovascular diseases;
- preparation for complex operations on the heart, lungs, aorta;
- need to detect congenital abnormalities of the heart valves;
- carrying out an examination aimed at assessing the patient's ability to work.
Contraindications
He alth problems that prevent stress echocardiography in Vladimir and other cities include acute myocardial infarction. Patients with aortic aneurysm, severe arterial stenosis, acute heart failure, hereditary defects are also not allowed to study.hearts. Due to the risk of blockage of the heart muscle valves by blood clots, stress echocardiography with exercise is contraindicated in patients who suffer from severe thrombophlebitis. The reason for refusing the procedure is also individual intolerance to the components of pharmacological preparations, which are mandatory introduced into the body in preparation for the study.
Relative contraindications
When absolutely necessary, the stress test may be subjected to:
- pregnant women;
- people with minor mental disorders;
- patients who suffer from obesity;
- persons with partial pancreatic dysfunction;
- diabetic patients who experience decompensation of the main manifestations of the disease.
The decision to conduct diagnostics in these categories of patients is made by the doctor.
Load test
Stress echocardiography (Nizhny Novgorod or another city - no matter where it is performed) can be performed using various stress tests. The nature of the test used is determined by the objectives and the objective clinical situation. For example, to determine the tolerance of the patient's body to increased stress, as well as suspicions of the likely development of heart attacks, dynamic tests are used. In this case, the study is carried out using a treadmill or bicycle ergometer.
More tolerable for elderly patients istreadmill load. In particular, such an approach to diagnostics does not provoke the occurrence of radicular pain, which can develop when using a bicycle ergometer, on which the patient has to sit in an uncomfortable position. The main disadvantage of the treadmill is the inability to generate graphs with the results of the study directly during the test. The factor that signals the need to stop the stress test is the excess heart rate.
Pharmacological test
About 40% of patients who require stress echocardiography in Yekaterinburg and other cities are not able to adequately endure increased physical activity. Such patients are prescribed a pharmacological test.
Currently widely used stress echocardiography with "Dobutamine". The introduction of a substance into the body opens up the possibility of simulating the conditions that occur during physical exertion. The use of this solution allows you to increase the level of blood pressure, increase the contractility of the heart muscle. The increase in tissue oxygen demand when using the drug causes manifestations that become a good basis for detecting signs of myocardial ischemia.
Dipyridamole is often used as an alternative to Dobutamine. The test is based on a gradual increase in the dose of a substance in the body. At each stage, the presence of violations of cardiac contractility of the myocardium is investigated. If, with the introduction of the priority norm"Dipyridamole" in the body, the heart rate is about 120 beats per minute, an additional dose of "Atropine" is applied in the amount of 1 mg. At the end of the test, 240 mg of Aminophylline, a drug that acts as an antidote to Dipyridamole, is administered intravenously.
Analysis of results
The result of stress echocardiography is obtaining two-dimensional graphic images. The latter make it possible to identify failures in the contractility of the left heart ventricle. When deciphering the results, the degree of thickening and mobility of myocardial tissues in individual zones is taken into account.
Preliminary analysis of charts is performed by a specialist immediately after they are received. Upon completion of the diagnosis, the cardiologist can view the video of the study in slow motion. Separate fragments of the procedure are often stored on computer disks and represent a good information base for subsequent diagnostic measures.
Where to do a stress echocardiography?
To conduct a study using a stress test or a pharmacological test, it is enough to contact the nearest cardiography center. Specialized offices of state medical institutions are capable of performing diagnostics. A more expensive option for the procedure may be to make an appointment at a private clinic that has the equipment necessary for testing and has the appropriately qualified specialists.
Benefits of diagnosing myocardial ischemia with stress echocardiography
Among the main advantages of the method are the following:
- An impressive list of opportunities to study the functioning of the heart muscle.
- Portability of echocardiography equipment, which allows testing outside the hospital.
- Relatively low cost of diagnostics.
- Possibility of a qualitative assessment of the nature of myocardial thickening.
- Safety of the procedure for the patient.
Flaws
If we talk about the disadvantages of stress echocardiography, it is worth noting, first of all, the presence of difficulties in assessing the quantitative results of samples. For this reason, the determination of accurate results is possible only when the diagnosis is carried out by an experienced, highly qualified researcher.
Among other things, technical problems often occur during tests. The probability of their appearance on average is about 5-10%.
In closing
Stress echocardiography is still quite an innovative method for studying coronary heart disease. Carrying out such a diagnosis is prescribed primarily to patients who have twitched with standard electrocardiographic tests, which did not allow them to obtain enough information to identify pathologies. Finally, stress echocardiography can detect coronary artery stenoses that remain unclear after angiography.
