Heart CT is a method of layer-by-layer scanning of the structures of the heart, based on the registration of an X-ray beam that has passed through the tissues using ultra-sensitive detectors. Computed tomography enables 3-dimensional reconstruction of the heart and is used to detect valve defects (calcification of the valves, developmental abnormalities), myocardial lesions (hypertrophy, scars), pathology of the pericardium and chambers of the heart, determination of myocardial contractile function.
The fields of application of heart CT in cardiology are extremely wide. The technique can be used to clarify echocardiographic data – assessment of the anatomy and functioning of the chambers, the condition of the valves in various cardiopathology. The study is a marker of coronary atherosclerosis and is performed to identify and assess the degree of calcification of the coronary arteries in patients with questionable stress tests, initial signs of cardiosclerosis, atypical pain syndrome; allows differentiation of non-ischemic heart failure (myocarditis, cardiomyopathy) and ischemic genesis.
Heart CT and coronary vessels is performed in the absence of reliable indications for invasive coronary angiography in the case of a suspected or doubtful diagnosis of coronary artery disease. As a method of non-invasive diagnostics, the procedure is indispensable for assessing the condition of coronary shunts and stents, detecting aneurysms, anomalies in the development of coronary arteries. In acute thoracalgia, it helps to carry out urgent diagnostics of PE, myocardial ischemia, aortic dissection, pneumothorax, and other pathologies accompanied by acute chest pain. The possibilities of heart CT in detecting tumors of the heart, constrictive pericarditis, thrombosis of the heart cavities are invaluable. The examination is carried out to clarify complex defects in which the main arteries, veins, bronchi, trachea are involved.
When planning a heart CT scan, contraindications are taken into account, including pregnancy, a permanent form of atrial fibrillation, frequent extrasystole, severe somatic condition and mental disorders. Since computed tomography involves the introduction of iodine-containing contrast, additional limitations to the study are the serum creatinine level > 130 microns / l (or > 1.5 mg / dl), hyperthyroidism, severe bronchial asthma, intolerance to iodine-containing drugs, excess body weight of the patient exceeding the maximum load on the tomograph (more than 180-220 kg).
Methodology of conducting
When performing a heart CT scan, it is recommended to maintain an interval after eating for at least three hours, do not take medications that increase heart rate (atropine, caffeine, theophylline, etc.) on the day of tomography. In patients with allergies to iodine-containing contrast, the issue of using hypoosmolar or isoosmolar contrast agents is being resolved. Before the procedure, an infusion catheter is inserted into the peripheral vein. The required heart rate for CT of the heart is less than 70-65 beats per minute. The patient is placed on the tomograph table on his back with his hands raised up, contrast is introduced. During the study of the heart, ECG synchronization is used in a prospective or retrospective mode. Scanning begins on inspiration after a short breath delay.
After scanning, the results are processed to recreate 3-dimensional reconstructions of the heart and blood vessels. According to the CT of the heart, the anatomy of the coronary arteries is analyzed (type of blood supply, branching variants, developmental anomalies); the presence and X-ray morphological appearance of atherosclerotic plaques (calcified, soft, mixed); the degree, localization and extent of stenosis (hemodynamically significant or hemodynamically insignificant), the state of shunts and patency of stents in the case of previous surgery. When assessing the functional parameters of the heart, the volumes and dimensions of the chambers, the thickness of the myocardial wall, contractility, the condition of the valve apparatus (the presence of stenosis or valve insufficiency) are taken into account.
The results are given to the patient in the form of snapshots, CD or DVD recordings, and a study protocol. Based on the data obtained, the cardiologist is determined with indications for further conservative treatment or cardiac surgery.