Myocardial infarction

Myocardial infarction - a disease characterized by the formation of necrotic lesion in the heart muscle as a result of infringement of coronary circulation. And myocardial infarction is usually observed among people older than 45 years. Men suffer from myocardial infarction in 4-5 times more often than women.
Etiology. The main cause myocardial infarction is thrombosis of a coronary artery (karunaratnam) as a result of atherosclerosis. Perhaps the development of myocardial infarction in the absence of organic changes in the coronary arteries due to their prolonged spasm. Factors predisposing to the development of myocardial infarction: fatigue, mental trauma, physical stress, Smoking, hypertension.
Pathogenesis. The development of thrombosis of a coronary artery contribute to atherosclerosis of these arteries, spastic their reduction (koronarospazm), changes in blood-blood (a reduction in blood heparin and decreased fibrinolytic activity of blood). Moreover, in conditions of deficiency of coronary blood flow creates a gap between the need in energy materials and the lack of their delivery. This is especially clear during exercise, when the blood pressure, as well as the excitement.infarct myocardial
Fig. 1. Heart attack posterior wall of the left ventricle with a gap (cross sections): 1 - the area of a heart attack; 2 - a blood clot in the back of the descending branch of the left coronary artery; 3 - the wall rupture of the heart. Fig. 2. The heart of the front-side of the left ventricular wall and interventricular septum on the background of scarring at the apex of the heart and in back papillary muscle: 1 - obliteration left circumflex artery; 2 - area of a heart attack; 3 - a blood clot in the right coronary artery; 4 - the old scar.
Pathological anatomy. For acute termination of blood flow to part of the heart muscle begins its anemia, and then death (necrosis Fig. 1-2). Later around the hearth necrosis formed inflammatory changes with the development of granulation tissue. Necrotic masses absorbed and replaced with scar tissue. Myocardial infarction, as a rule, develop in the left ventricle. Usually necrosis captures layers of the heart muscle, located under the endocardium (subendocardialnah form), but in severe forms can cover the entire thickness of the muscular layer (transmural heart attacks); thus there is the focal fibrinous pericarditis. Sometimes fibrin is deposited on the inner membrane of the heart, in the areas corresponding to necrosis of the myocardium,- wall postinfarction thromboangiitis. Thrombotic masses can break off and enter the total current of blood, causing an embolism vessels of the brain, lungs, abdomen and other
The clinical picture. In 1909, B. N. Samples and N. D. Strazhesko clearly and accurately described the clinical picture of acute myocardial infarction (Obraztsova - Strazhesko syndrome) was first identified options for its flow. Myocardial infarction begins in most cases, with pain in the heart, in the chest, sometimes covering the entire breast. They are intense, sometimes painfully "preying on", it is only the feeling of painful embarrassment. Pain in myocardial infarction very long (1/2 - 1 hour to several hours) and so intense that patients often rushing about from pains in bed, unable to find a place. As a rule, pain iradionet in the left shoulder and left hand, less frequently in the right shoulder.
Pain in heart attacks can go away and come back. Pain associated with myocardial infarction, as a rule, suddenly, after the unrest, increased muscle tension, and sometimes at the conclusion of the period of frequent and intensified attacks of angina pectoris (see). In some cases, to the fore in the clinical picture of myocardial infarction are shortness of breath and asthma cardiac asthma (asthmatic form of myocardial infarction). Sometimes pain in myocardial infarction are located in the abdomen. Patients feel that pain occur in the stomach or intestine (gastralgia form of myocardial infarction).
In rare cases, myocardial infarction without pain (painless form), and manifests itself immediately symptoms of cardiovascular insufficiency. Such variant of the disease is more likely to occur with repeated myocardial infarction.
The pulse of myocardial infarction small, frequent, often irregular. Blood pressure rises in the period of pain, and then begins to fall. The fall of it can be harsh and then develops a picture of collapse (cardiogenic collapse or shock). It is characterized by sudden weakness, paleness of skin, cold sweat, a faint flicker of pulse. The heart sounds in myocardial infarction become deaf, may listens pericardial friction noise. Sometimes heard and gallop rhythm. Meet heart arrhythmia (see) - arrythmia, blockade, atrial fibrillation, paroxysmal tachycardia. Poor circulation in myocardial infarction usually develops in left ventricular type: heart expanded mainly left lung congestive wet wheezing, may occur choking on the type of cardiac asthma, and further and pulmonary edema. 2-3-day sickness appear fever and leukocytosis by suction from the hearth of myocardial infarction necrotic products. The more necrosis, the higher and longer temperature rise and leukocytosis.
Fever (usually no more than 38 degrees) lasts 3-5 days, but sometimes more then 10 days. The number of cells increases to 12 000 to 14 000. From the 2nd week of the disease is accelerated ROHE, and the number of leukocytes is reduced.
Complications of myocardial infarction: 1) breaking hearts observed in the first days of myocardial infarction, before the formation of scar tissue in place of the heart muscle necrosis (death comes suddenly); 2) began testing leading to death; 3) acute cardiac aneurysm (see); 4) embolism causing the disorder of cerebral circulation, heart lung, damage to the organs of the abdominal cavity (see Thromboembolic disease).
The diagnosis. In addition to the clinical picture of special importance in electrocardiographic data, as with their help it is possible not only to establish the presence of myocardial infarction, but also to specify the localization, the depth and breadth of the defeat of the heart muscle. The differential diagnosis between myocardial infarction and angina should be taken into account that the pain in myocardial infarction differ from angina its intensity, pervasiveness and duration, not cropped nitroglycerin, and in some cases, and drug abuse.
The prognosis of myocardial infarction serious and depends on the prevalence of necrosis, General condition of the heart muscle, and following the sick in bed. The formation of a scar on the place of myocardial infarction is not less than 1/2 months, and during this period, the patient should be kept under continuous medical supervision. A special danger for the patient at any stage of the disease are physical tension, the early rising from bed, even natureline when urinating. Prediction must be especially careful in the first days of myocardial Re-infarction myocardial infarction significantly worsen the prognosis.

  • Treatment
  • Care
  • Exercises in myocardial infarction