- What aneurysm
- How does the heart
- What to aneurysm notexploded
- heart aneurysm in children
If a person has become faster than before, tired, occasionally complains of a dry cough, sometimes feels a shortage of air or had swollen limbs - it does not necessarily mean that he has tosleep or relax.Such symptoms may indicate the development of an aneurysm of the heart - the disease, which is most often a complication of myocardial infarction, but may appear as a result of hypoxia, cardiac muscles, which developed as a result of other causes.
This term refers to the protrusion of the outer wall of the heart or the partition between his ventricles or atria.Thus, there is a normal body wall indentation sized finger or a more pronounced (1 to 20 cm).It is directly connected with the cavity of the heart, with the remaining three sides it is surrounded by its own wall.The latter, like, and are formed from the same fabric as the rest of the body, but they are modified and do not perform the same operation as normal (eg, the myocardium of the heart of the aneurysm is not reduced).
aneurysm is formed when some portion of the heart no longer receives it needs for oxygen.It can be acute - with prolonged spasm or instant overlapping the artery that feeds the heart thrombus or embolus (a larger diameter than the supply vessel will suffer, the greater portion of ischemia).Lack of oxygen can develop chronic - when carrying blood to the heart vessels gradually education grows, overlapping the lumen (usually atherosclerotic plaque), or when the coronary artery compresses the growing tumor.
heart aneurysm develops not only in the ischemic area, but also where there is an inherent weakness of the heart wall, or violation of its contractility.
Aneurysms of the aorta of the heart - it is a separate disease, not associated with the protrusion of the heart wall, and discussed in a separate article.Here, in the largest artery of the body - the aorta - developing an extension that is less stable than the protrusion of the heart wall.
Blood, available in the ventricle, pressure on all body wall evenly.But ischemic or thinning area harder than others, carry the pressure, and he begins to cave in under him, stuck out.So it formed an aneurysm.in the area of the aneurysm myocardium can not be reduced at all (be akinetic), and may be bulging during systole and "get involved" in diastole (called dyskinesia wall).
blood pressure acts on the aneurysm wall, leading to its further thinning.If this pressure is not controlled, it develops a complication of the disease, as a rupture of the aneurysm wall, which is often lethal.
heart aneurysm has a 2 "favorite" localization - where blood pressure as much as possible.It:
- left ventricular wall (it works great right in the norm) that protrudes outwards;
- interventricular septum, which bulges into the right ventricle moan.
In these areas more likely to develop myocardial infarction, after which 10-25% of the cases and forms of heart aneurysm.
aneurysm is dangerous not only to their rupture, but complications such as:
- Heart Failure.It develops due to the fact that part of the volume of blood remains in the cavity of the aneurysm and is not included in the general circulation.The larger the aneurysm, the greater the amount of blood lost.
- mural thrombus.They appear in the cavity of the aneurysm, for the reason that the blood is not exchanged every 0.8 seconds, as in the heart during its operation.The stagnant blood "turns on" the clotting system, because of what and formed clots.These blood clots can migrate out of the aneurysm cavity, forming thromboembolism, and clog blood vessels of suitable diameter, causing the death of the body portion, fueled this vessel.
Radical treatment of the aneurysm - surgery, when the protrusion is excised, and formed after the defect is sutured.Such treatment is associated with risks for the patient.
How does the heart
This organ about the size of a human fist, located in the chest cavity.Normally, it takes up space on the right edge of the sternum to a line drawn through the middle of the left clavicle.The fifth intercostal space left on this line, if you put a finger to 2, you can feel the heartbeat.There is his tip.
heart consists of three layers.The inner and outer - endocardium and epicardium - consist of a thin fabric.From the first heart valve made his task - to prevent the blood swirls inside heart.The outer layer, the epicardium, spliced with the lining of the heart (heart bag, pericardium).Its mission - to strengthen the heart wall.
Middle layer is best developed.This is the myocardium - the muscle layer.When cutting in systole, it emits oxygen-rich blood from the lungs came in large vessels coming from the heart.In diastole (relaxation period), the heart, which is essentially a pump, creating inside a negative pressure sucks the blood inward from the vena cava.
Reducing heart chambers, which in humans four (2 2 atrium and ventricle) occur in a specific order.Manages the sequence of the particular muscle cells with electrical activity.They paved among "ordinary" cardiomyocytes "track", along which extends an electrical impulse - from the atria to the ventricles.In this manner they are reduced: first the atria and then the ventricles.
inner shell forms the valves - and two trilobal education, which must pass the blood in one direction only.Reasons
disease Almost 95% of heart aneurysm is the result of myocardial infarction, mainly when it is developed in the left ventricle.This aneurysm ventricle of the heart is not always develop at once (the classification of the disease will be discussed below), it can trigger such events in post-MI as:
- consumed a large amount of liquid;
- exercise, causing tachycardia;
- recurrent myocardial infarction.
Besides myocardial infarction cardiac aneurysm may cause:
- injuries: closed (with a blunt object) and open (when a traumatic thing made a hole in the chest wall and the wounded heart), including postoperative - caused after heart surgery;
- wall congenital heart disease: more on this, read on - in the "heart aneurysm in children";
- damage by ionizing radiation of the heart, when radiation therapy to the chest organs;
- infectious heart damage: in syphilis, tuberculosis, infective endocarditis, rheumatic disease, fungal endo- or myocarditis.Germs can get into the heart cavity of infected thrombi, if leg vein or (less often) hands were inflamed.The latter is characteristic for people after an accident, to engage in extreme sports, as well as combatants.
Some causes require more detailed consideration.
This - the most common cause of cardiac aneurysm.It occurs when the artery feeding heart portion overlaps more than 75% of thrombus, atherosclerotic plaque or emboli.As a result, site of the heart, which is fed by this vessel, dies at greater or lesser extent.
least likely caused by a sudden heart attack - in response to the entering of a vasoconstrictor substances in the body - is a spasm of the coronary artery (the name is a vessel that feeds the heart).Most often there develops deposition "wrong" fats - atherosclerosis.
wither may vary the depth of the heart section.In some cases, it suffers only endocardium or epicardium, myocardium and almost unaffected.After this heart attack cardiac aneurysm does not develop.Over 90% of cases of this disease - a complication after transmural, that is, covering all wall myocardial infarction.
myocardium can not regenerate, so the location of dead heart tissue forms a scar.Scar tissue properties differ significantly from the muscle, the blood pressure so it is beneath (mainly, when there is only at the stage of formation of) bends that forms an aneurysm.
For postinfarction aneurysm is characterized by such symptoms:
- localization - in the left ventricle (in which the blood pressure is highest);
- large size (more than 5 cm in diameter);
- diagnosed on ultrasound of the heart in the first weeks after a heart attack;
- prone to a progressive increase in the probability of a break.
Germs do not cause directly to the development of an aneurysm, but they, through the allocation of toxins and other waste products provoke an inflammation of the heart muscle - myocarditis.scar - In some cases, especially if the place of dead connective tissue is formed by cells of the myocardium.Here and there is a cardiac aneurysm.
most dangerous of its ability to cause myocarditis such microorganisms:
- influenza viruses;
- enteroviruses Coxsackie;
- diphtheria bacillus;
- fungus Candida;
- Epstein-Barr virus.
heart tissue heart aneurysm in infants often occurs when in utero disrupt the normal development of the heart tissue, eg, in the myocardium "caught" the connective tissue.While the fetus is in utero, ensuring its tissue of oxygen carried by saturated with this gas maternal blood.As soon as he is born, he has to do it himself - by breathing.First breath and cry greatly increase the pressure in the vessels that carry blood from the lungs to the heart, which increases the intracardiac pressure.As a result, where the thin, there and tear - supple, malformed portions sag under the pressure of the blood.Since forming an aneurysm.
chances of abnormal areas above, if during pregnancy a woman:
- drink alcohol;
- takes medication for the treatment of pregnant unresolved;
- suffered measles, influenza, rubella;
- working in hazardous occupations.
In some cases, the aneurysm fade with time.But predisposition is, and the chance of recurrence of the aneurysm - if borne viral or bacterial infections - higher than that of other people.
If surgical correction of various defects of the heart surgeons put on the heart of the seams.If the healing goes well, the scar in this place is thin, the heart does not interfere.But even if the operation went perfectly, but in the postoperative period was tachycardia, or increased intraventricular pressure, can form a large and extended scar after bulges under pressure, and there is formed an aneurysm.
Cardiac aneurysm can occur as a result of direct injury of the heart, and when it injury or compression, when the integrity of the chest does not change.aneurysm formation mechanism is different:
- if there has been an open wound, at this point formed a scar, and in its place - an aneurysm.Pathological enlargement of the heart area may develop through a different mechanism: when wounding thing to do in the heart of a small hole out of it gradually, with each reduction in pericardial cavity is ejected a small amount of blood.The work joins the connective tissue, it "sews" the defect so as to form a "bag" of adhesions, in which blood is present.This is - the false aneurysm;
- in the case of damage to a closed fluid from the blood vessels into the bruised leaves of the heart tissue, soaking her.This causes myocarditis, after which the connective tissue formed at the site of normal prior-cardiomyocyte cells.
Toxic myocarditis as a cause of heart aneurysm
inflamed myocardium of the heart is not only under the influence of microorganisms.Some substances are poisons for myocardial cells, causing inflammation therein.It:
- large amounts of thyroid hormones;
- increased amount of uric acid in the blood (gout, diseases of the kidneys);
- substances for which there is an individual intolerance (allergy).Most often it is antibiotics, local anesthetics, vaccines, serum substance injected stinging insects or poisonous animals.
example, lupus erythematosus and dermatomyositis.Here, the heart is affected its own antibodies, which the immune system has developed, considering the myocardial cells alien.At the site of the inflamed tissue forms a scar, and then - an aneurysm.
inflammation of the myocardium, followed by the formation of scar here can be caused by radiotherapy of the tumor diseases of the organs, which are localized in the thoracic cavity.Directional, such as lung cancer, gamma ray beam falls on the heart and that it causes inflammation, followed by scarring.
There disease, the cause of which is unclear (this is called the word "idiopathic").Here normal myocardial cells progressively replaced by connective tissue, heart wall changes its properties, becomes pliable and eventually aneurysm formed here.
Aneurysm of the heart - it is education, which can have a different location, wall structure, dimensions, shape and mechanism of formation.If the disease has developed as a result of a heart attack, it is important and even the timing of its occurrence.Therefore, the classification of the disease is extensive.It is carried out on the basis of cardiac ultrasound (echocardiography).
At the time of appearance
so classified only postinfarction aneurysm, and they are:
a) Acute .Formed in the initial 14 days of the occurrence of the death of myocardial cells;wall consists of of dead myocardium.If the protrusion is small, there is a chance that the body itself of its "smooth out" with the help of dense scar.But if a large degree, it is very dangerous from any increase in intraventricular pressure may increase rapidly and even rupture.
b) Subacute , appearing at 3-8 week post-MI.The wall consists of a thickened endocardium, there are cells of the connective tissue of varying degrees of ripeness.These aneurysms more predictable, as the fabric of their performing, almost formed and is more dense (less responsive to fluctuations in intraventricular pressure).
in) Chronic , which are formed after 8 weeks from the date of formation of myocardial necrosis.The wall consists of three layers: the endocardium and epicardium, between which is the former muscle layer.
Chronic aneurysm, having, though thinned, but rather a dense wall, grow slowly and rarely broken, but they are characterized by other complications:
- clots that are formed as a result of stagnation;
- rhythm disorders, the cause of which is that the normal myocardium is interrupted by an aneurysm consisting of tissue, which does not conduct impulses.
On the mechanism of formation
- True .They consist of the same walls as the heart.Intramural may contain different amounts of connective tissue.This type we are considering.
- False .The wall of these aneurysms is made up of leaf bags or cardiac adhesions.Blood is in such an artificial "bag" gets through a defect in the wall of the heart.
- Functional .Myocardium - a wall of an aneurysm - is quite viable, but has low contractility.It protrudes only during systole.