Hypertrophic cardiomyopathy: symptoms, causes, forms and treatment
Author Ольга Кияница
Hypertrophic cardiomyopathy (HCMC) is a condition in which some of the cardiac muscle becomes thickened and stiff. This makes it difficult for the heart to work and pump blood throughout the body.Depending on where the thickening occurs, there are some or other hemodynamic disorders.
HCM is considered the most common hereditary heart disease and affects about 1 in 500 people in the UK. Pathology can affect adults and children, as well as men and women ...
To establish the diagnosis of hypertrophic cardiomyopathy, various methods of research using the type of echocardiography, electrocardiography, magnetic resonance imaging are used. In the future, in most cases, surgical treatment is performed, which significantly improves the prognostic conclusion and quality of life of the patient.
Video: Hypertrophic cardiomyopathy. Death in absolute health
Description of hypertrophic cardiomyopathy
In HCMC, the muscular walls of the ventricles of the heart (lower chambers) become thickened. In the area of damage, muscle cells may seem disorganized (or "disorderly"). HCM usually affects the left ventricle and, in particular, the interventricular septum (the region of the myocardium in the middle of the heart that separates the right and left ventricles). However, the disease can also affect the right ventricle.
"At present, the criterion of HCM is considered to increase the thickness of the myocardium more than or equal to 1.5 cm in the presence of diastolic dysfunction (impaired relaxation) of the left ventricle. (en.wikipedia.org)
On average, the thickness of the wall of the left ventricle in an adult is 12 mm, while in HCMC, the figure reaches 15 mm or more.
The thickening of the myocardium disrupts the ventricle, since it is difficult to relax and fill the heart chamber with blood.Depending on the area and the size of the thickening, the volume of the ventricle (the amount of blood it can hold) is normal or reduced (holds less blood than usual).
Types of hypertrophic cardiomyopathy
Depending on where the thickened area is located in the heart, the corresponding types of HCM are isolated. This division also affects what symptoms may occur and what treatment will be prescribed.
- Apical hypertrophy - a thickened area is at the base of the heart, which often leads to a decrease in the volume of the ventricle.
- Symmetrical hypertrophy - thickening affects the entire left ventricle, which also leads to a decrease in its volume.Sometimes this condition is called "concentric" hypertrophy.
- Asymmetric hypertrophy of the septum without obstructions - defeat occurs in the area of the septum of the heart."Without obstacles" means that the thickening does not affect or limit the movement of blood ejected from the heart.
- Asymmetric hypertrophy of the septum with an obstruction - a thickening similar to the previous type concerns the interventricular septum of the heart. However, unlike the above variant, the thickened area forms an obstacle that affects the blood circulation that leaves the heart. When this happens, the ventricle must work hard to pump out blood. The mitral valve can also be damaged, which can not normally close. This means that the blood forms a reverse outflow into the left atrium, called mitral regurgitation. In some cases, the disorder can cause noise, which is sometimes heard through the stethoscope.
Causes of hypertrophic cardiomyopathy
HCMC usually occurs against a background of a genetic mutation and, as a rule, one gene disorder (rather than several, combining together). Disease is often inherited as an autosomal dominant trait. This means that the mutated gene is found on one of the autosomes (not linked to the sex of the chromosomes). Therefore, the child from one sick parent will have a 50% chance of inheriting hypertrophic CML.
Mutations in different genes can influence the development of signs of HCM. Therefore, even at birth with a mutation in a person, the disease may not develop. Also in this case, any symptoms will not appear until adolescence or earlier than 20 years.
In some patients, minor symptoms are identified. Sometimes it happens at an older age and talk about the "late start of HCMC." In addition, there are some genetic diseases, such as Anderson-Fabry disease, which can be complicated by HCM.
Taking into account the reasons mentioned above, it is important that the relatives of the first line (children, brothers, sisters and parents) associated with the patient on HCM, also be examined according to the diagnostic plan. In such cases, genetic testing is first considered, which includes analysis of the genotype, respectively, of the hcmp mutation, as determined by the patient.
In one family, relatives may suffer from the same genetic mutation, but it often manifests itself in different ways, because of what the symptoms and severity of the course of the disease is different.
Symptoms of hypertrophic cardiomyopathy
There is a wide variation in the symptoms of HCMC, while some people may not have symptoms at all, but others have a very serious clinic.
Common symptoms include the following.
- Palpitation (feeling that the heart beats too fast, hard or like "flutter"). Such sensations are caused by arrhythmias (when electrical impulses that control the rhythm of the heart are disturbed).
- Pain in the chest - is caused by a decrease in the level of oxygen entering the heart.
- Dizziness or fainting occurs due to a decrease in the amount of oxygen or blood flow in the brain, most often against the background of arrhythmias.
- Shortness of breath or shortness of breath - the fluid accumulates in the lungs, making breathing difficult.
- Fatigue - when the function of the heart is disturbed, less energy is transferred to the tissues, which causes excessive fatigue.
HCMC can cause arrhythmias (abnormal heart rhythms), since broken muscle cells often affect normal electrical conduction in the heart, which controls the heart rhythm. This violation leads to a change in the rhythm of the heart, and it too quickly, slowly or randomly decreases. Most often in HCMC, atrial fibrillation, ventricular fibrillation and ventricular tachycardia are determined.
Atrial fibrillation (AF) - is associated with a violation of electrical conductivity, which usually contributes to the reduction of the heart muscle. With AF, multiple electrical impulses are generated from the atrial walls, which cause them to rapidly contract and work inconsistently. This often leads to the formation of a turbulent blood flow in the atrium, while the heart ejects blood less effectively. Some of these impulses pass into the ventricles and can cause a typical fast and irregular heart rhythm.
AF may increase the risk of blood clots, which contributes to the development of a stroke. It is important that most people with AF take appropriate medications to prevent such pathological changes.
Ventricular tachycardia (VT) - occurs due to abnormal electrical activity, formed in the walls of the ventricles. In this case, the heart contracts abnormally quickly (more than 100 beats per minute). This rapid rhythm can cause the heart to not effectively pump blood, which in severe cases leads to loss of consciousness.
Ventricular fibrillation (FV) - with this pathology, the ventricles contract uncoordinated, they seem to "tremble" and do not work normally, so the blood is pumped inefficiently. This condition is life-threatening, since it can lead to cardiac arrest, so in such cases urgent treatment with a defibrillator is required.
Obstruction of left ventricular outflow
This condition occurs when a thickened area of the heart muscle prevents blood from leaking from the left ventricle.Symptoms include fatigue, shortness of breath, and chest pain. Some people have symptoms during rest, while other patients complain during a workout when the heart is stressed.
Complications of hypertrophic cardiomyopathy
HCM can lead to additional complications.
- Heart failure - the heart stops working effectively because of what it "fails" to pump enough blood at an allowable pressure to meet the needs of the body. This complication is determined by weight gain (due to fluid retention), shortness of breath, coughing, swelling, palpitations, dizziness and fatigue.
- Stroke - there is a slight increased risk of stroke in people with AF. Usually this condition is controlled by medication.
- Sudden cardiac death can occur due to dangerous arrhythmias, such as ventricular fibrillation, which can cause the heart to stop. The risk of sudden death is relatively small.
A note on the progression of HCM
In some people, HCMC develops to a stage known as the "burnout phase" or scarring. This is when the hypertrophied left ventricle begins to lose muscle cells and connective tissue develops in their place. The chamber cavity expands (increases). This pathology can lead to the formation of dilated cardiomyopathy, rather than hypertrophic. To support cardiac function, additional therapy may be required.
Diagnosis of hypertrophic cardiomyopathy
There are several tests that are often used to diagnose HCM.
- The history of the disease - draws attention to any previous symptoms that may be not only in the patient, but also in other family members. In doing so, the patient's pedigree is carefully studied.
- Physical examination - search for any signs of the disease and other health problems.
The results of the medical history and physical examination provide important information for the diagnosis and determine which of the following tests are needed:
- ECG (electrocardiography) - the electrical activity of the heart is evaluated and, if there are characteristic changes, arrhythmias are determined (abnormal heart rhythms). The ECG can also be performed during exercise. Most patients with HCM have abnormal ECG.
- Echocardiography (echocardiography) - an ultrasound scan of the heart, which is based on the use of sound waves to create an echo, when they fall into the diagnosed parts of the body. The method allows to consider the structure of the heart and its functionality.
- An ECG stress test is tests performed during exercises, for example, on an exercise bike or a treadmill.
- Holter monitoring - ECG recording is performed for a certain period of time (for example, several days). "Holter" is an ECG device that is worn at the waist or in the pocket, which allows you to move and walk.
- MRI (magnetic resonance imaging) - a scan is performed that creates high-quality images and is used to view the structure and functions of the heart. MRI photos clearly show any presence of fibrous tissue.
Treatment of hypertrophic cardiomyopathy
The goal of treating patients with HCM is to control symptoms and reduce the risk of complications. Some people may not need treatment at all.
- Beta-blockers - they are designed to prevent the development of arrhythmias, can also be used to reduce the symptoms of obstruction of outflow from the left ventricle.
- Calcium channel blockers - reduce the force with which the heart contracts, thereby reducing the obstruction of ventricular outflow.
- Antiarrhythmic drugs - reduce the severity of abnormal heart rhythms and help keep the heart rate within the limits of the norm.
- Anticoagulants (blood thinners) can be used in people with arrhythmias to reduce the risk of blood clots, which can lead to a stroke.
- Diuretics (diuretics) - reduce the amount of fluid in the lungs or around the ankles by stimulating the kidneys to urinate. Although they are not always provided to patients with HCM, they can be useful in some cases.
Some people, when drug treatment was ineffective or dangerous arrhythmias were identified, special devices can be implanted to eliminate irregular rhythms. In rare cases, a pacemaker can be used to treat LVOTO symptoms.
- Cardioverter-defibrillator - is installed in any dangerous forms of arrhythmia, which otherwise could lead to cardiac arrest and sudden death.
- Pacemaker - these devices either send electrical impulses on demand, or work continuously, which allows you to maintain a normal heart rate.
Indications for the use of a cardioverter-defibrillator
The European Society of Cardiology has developed guidelines for determining the level of risk for sudden cardiac death for a particular patient. Danger is calculated taking into account a number of risk factors. Some of them are as follows:
- Age of the patient.
- The thickness of the left ventricle.
- The presence of a family predisposition to sudden death.
- Presence of fainting (loss of consciousness) due to arrhythmias.
- The level of blood pressure during exercise.
- Presence of episodes of ventricular tachycardia.
Patients with a high risk of sudden death will usually be offered a cardioverter-defibrillator implantation to reduce the chance of cardiac arrest.
Surgical effects in HCM include removing the affected area of the heart muscle in order to reduce obstructions and optimize blood flow through the heart chambers. To do this, one of the two most practicable methods is used today.
- Alcohol septal ablation - is based on a very accurate introduction of alcohol directly into the zone of thickening of the heart. This reduces the area of the heart muscle immediately around the site of the injected substance, which in turn reduces the size of the pathological formation. This is a very specialized form of treatment and is not suitable for everyone.
- Septal myectomy - during this operation, a part of the thickened muscle is removed, which makes it possible to improve the permeability of the heart chamber for blood flow. This form of surgery is performed on the open heart.
Heart transplantation is an extreme and accessible to a small number of people method that can be performed by transplantation. Indication for its conduct is a serious condition of the heart and a lack of response to treatment. During the operation, the unhealthy heart is removed and the heart is transplanted from the donor.
In addition to drugs and medical devices, ways can be used to reduce the effect of HCM on lifestyle. Below are recommendations that can help.
- The use of alcohol should be minimized - with excessive use of alcoholic beverages, the heart rate rises and blood pressure increases.
- It is important to practice a healthy diet - a balanced diet can help maintain body weight within normal limits, which will reduce the effect on the heart, and will also strengthen health.
- Reducing salt intake can help reduce water retention in the body and normalize blood pressure, especially with severe cardiac dysfunction. The specific amount of salt consumed is discussed with the attending physician.
- Smoking cessation is especially important, as it is a direct way to improve health, as well as the efficiency of the heart and blood vessels (because of smoking, the oxygen level in the blood can decrease, and the blood vessels may contract). The therapist or a special support service for smokers may help to stop smoking.
- Use of caffeine should be minimized - some people are more sensitive to caffeine than others, and this can cause them to flutter atrial. For those who are sensitive to caffeine, you must limit the amount of tea and coffee consumed with caffeine and avoid consuming high-calorie caffeine (for example, energy drinks, strong coffee and high cocoa chocolate).
In addition, people with heart disease are recommended to perform exercises. Moderate charging can be useful for people with HCM, depending on what symptoms are detected. In the presence of HCM, it is important to talk with your doctor about what exercise is appropriate in a particular case. If possible, you can conduct cardiac rehabilitation, which involves the implementation of special physical exercises.
Video: Hypertrophic cardiomyopathy. Why the heart is angry
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