Coronary angiography( coronaroangiography) - Causes, symptoms and treatment. MF.
Apr 28, 2018
Indications for coronarography
Procedure Decoding of results
It is known that in the heart there are blood vessels that supply blood with oxygen contained in myocardium( heart muscle).These vessels are called coronary( coronary, or their own heart).Their normal functioning is very important for the proper functioning of the heart muscle, which, in turn, depends on the well-being of the whole organism. In the case of clogging of the lumen of blood vessels with a thrombus or an atherosclerotic plaque, acute or chronic hypoxia of the heart tissues( lack of oxygen) occurs, leading to necrosis( tissue death).As a result, such diseases as ischemic heart disease( IHD) and myocardial infarction develop. In most cases, such diseases are easily diagnosed by the results of clinical examination, ECG and ultrasound of the heart.
But it is not always possible to determine the presence of pathology of the coronary arteries on the basis of only these data and to develop a certain therapeutic tactics. Sometimes a doctor needs to literally "look" in the heart of a person to understand what pathological processes are taking place in this important organ. Is it feasible?
The possibilities of modern medicine are constantly expanding. A hundred years ago, doctors could not imagine that someday they would be able to see from inside the heart of a living person, to see how it beats, to assess how its internal structures and blood vessels work. At present, all this has become possible thanks to special equipment and high-tech research methods. Coronaroangiography( CAG) is one such technique.
Coronary angiography( or coronary angiography) is an instrumental method for diagnosing cardiovascular diseases, which is carried out by introducing an X-ray contrast substance into the cardiac system of the heart, as a result of which the doctor receives X-ray images of the coronary arteries, followed by an assessment of their patency. This study allows to determine the degree of blood flow disturbance in these arteries due to thrombus, atherosclerotic imposition, vascular spasm( for example, as with Prinzmetal angina), clarify the presence of myocardial ischemia, and determine further actions of the doctor in terms of cardiosurgical treatment - the need for stentingthe arteries or aorto-coronary shunting( CABG).
Indications for coronarography
The main indications for this diagnostic method are the following:
- acute myocardial infarction in patients whose stenting is regarded by the doctor as necessary( within the first 12 hours from the onset of clinical manifestations);
- severe stable angina pectoris 3 - 4 FC( functional class);
- stable angina with signs of severe ischemia with minor physical exertion;
- variant angina of princemetal;
- absence of effect from the spent drug therapy, in this case the question of the expediency of stenting or CABG is being decided;
- a previous myocardial infarction accompanied by fatal rhythm disturbances( ventricular fibrillation, complete AV blockade, etc.) or clinical death;
- high risk of sudden cardiac death;
- impossibility of ECG or ultrasound of the heart with exercise( low tolerance of physical activity, as well as for patients with low ejection fraction by ultrasound);
- before surgery on heart valves in patients over forty years of age, as well as with chest and heart pain;
- specification of the diagnosis for clinical or occupational indications - in cases when the results of other survey methods are questionable;
- recurrence of angina or myocardial infarction within 9 to 12 months after stenting and CABG, respectively.
Contraindications for coronarography
There are no absolute contraindications for this method.
From the relative contraindications can be noted the following: acute infectious diseases, anemia( reduction of hemoglobin in the blood), pathology of the coagulation system with a possible risk of prolonged bleeding, stroke, acute or chronic diseases of other organs( acute surgical or gynecological pathology, decompensation of diabetes, bronchialasthma, etc.).
For each patient, indications and contraindications are determined by a cardiologist, cardiac surgeon, and, if necessary, by physicians of other specialties, strictly individually.
Preparing for the
Study Before drinking coronary angiography, it is very important to keep drinking and eating regimens. The study is performed strictly on an empty stomach( the last meal for 6 to 8 hours), since it is possible to develop vomiting during intravenous contrast and aspiration( ingression) of vomit. Two to three hours before the study, it is allowed to drink not very large amounts of clean drinking water for the proper functioning of the kidneys, since they have to remove the contrast material from the body.
In the case of a planned research, when a patient is sent from a polyclinic or a cardiac hospital, the following examination methods should be in his hands: a general urine test, a clinically developed blood test with platelet count, prothrombin index, clotting time and other coagulation factors, biochemical blood test, HIV tests, syphilis, hepatitis B and C, ECG results, echocardiography( ultrasound of the heart).
If the patient is delivered for urgent investigation( ambulance team, cardiac or resuscitation department with suspicion of myocardial infarction), the survey data can be carried out urgently if necessary.
How is coronarography performed?
Coronary angiography is an invasive method of diagnosis, that is, in the process of research is introduced into the tissues and organs of the human body. It is carried out in planned or emergency order. In a planned examination, the patient is hospitalized a few days before in the cardiological or cardiosurgical department of the hospital, where the necessary diagnostic methods are performed, as described above, at the discretion of the attending physician.
Before the nurse takes the patient on a gurney to the X-ray room, he undergoes premedication - the administration of analgesics and sedatives( ketorol, Relanium intramuscularly or intravenously).The patient is then transferred to the desk in the room, an anesthetized place for puncture of the radial artery( on the wrist) or femoral artery( in the groin) by the method of subcutaneous anesthesia with lidocaine or other anesthetics, then proceed directly to the puncture( puncture of the skin and artery).After the access to the artery( most often radial), an introducer is introduced into it - a sterile disposable tube with a valve preventing the ingress of blood into it and a side port for introducing contrast. Through the introducer introducer is introduced, reaching the radial artery of the aorta with coronary sinuses in it. Next, a catheter is inserted into the conductor and installed in the mouths of the right and left coronary arteries, an X-ray contrast material is introduced through this catheter, which allows you to see the artery shadow on the screen, as the arteries and heart absorb x-rays without contrast. At the same time, an X-ray examination is performed, which makes it possible to evaluate the coronary artery in different projections( the artery lies not in one plane).
The results of contrasting are displayed on the installation screen, and then saved in the computer with further evaluation and interpretation of the results. After a successful contrast, the catheter is either removed or the doctors decide whether to have an emergency balloon angioplasty or insert a stent into the narrowed artery.
After the end of the procedure, a pressure bandage is applied on the wrist, which does not require further dressings, and the patient is delivered to the ward. The whole procedure takes about 15 - 30 minutes, without causing painful sensations in the patient, not counting the puncture site( puncture).
After a routine examination, the patient remains in the cardiology department for several days to assess the general condition and decide on further treatment options. If necessary, the time of hospitalization can be increased in accordance with the need for cardiosurgical treatment.
In the case of an emergency test, the patient is transferred to the cardiovascular department for further monitoring and treatment.
Interpretation of the results of coronarography
The evaluation of data obtained during coronary angiography is performed by an x-ray surgeon, cardiac surgeon and cardiologist. Depending on the degree of narrowing of the coronary arteries, the following terms are distinguished:
- occlusion of - complete blockage of the artery by an atherosclerotic plaque or thrombus - the lumen of the artery is narrowed by more than 90% according to the results of coronary angiography;
- stenosis - partial narrowing of the artery lumen by 30 to 90% - distinguish estuarial stenosis( at the mouth of the artery or no more than three millimeters from its origin), local stenosis( over 1 to 3 mm of the artery), extended stenosison a significant portion of the artery narrowing its lumen);
- aneurysm of the artery ( protrusion of the wall, which interferes with normal blood flow and is fraught with rupture of the wall with bleeding);
- calcification of the artery ( deposition of calcium salts, usually in combination with atherosclerotic plaques in the artery wall, which also calls for narrowing and disturbance of blood flow along this artery).
The figure shows partial obstruction of the coronary artery.
The results are important for doctors in terms of the need for surgical treatment. So, for example, with a degree of narrowing of the artery lumen by more than 75%, the patient is shown cardiosurgical reperfusion( restoration of blood flow) of the myocardium.
Complications of coronarography
Since this study is invasive, and especially carried out on the heart, there is a risk of complications developing in statistics in two cases out of a hundred. Mortality in coronary angiography is less than 1%.However, in very rare cases, it is possible to develop ventricular fibrillation, coronary artery thrombosis with the development of extensive myocardial infarction, stroke, thrombosis of the radial artery, infectious inflammation at the puncture site, acute renal failure as a response to the excretion of contrast through the kidneys, allergic reaction to contrast medium, up to the development of anaphylactic shock.
Prevention of complications is a careful collection of anamnesis for kidney diseases, anaphylactoid( allergic) reactions, especially for iodine preparations, as well as the timely administration of anticoagulants( heparin, fractiparin, warfarin).
The remote complications may be the statistical data that low doses of radiation, obtained during visualization of the heart, increase the risk of cancer in patients by an average of 3%.
Doctor therapist Sazykina O.Yu.