Cardiac arrhythmia - a very complicated section of cardiology. The heart of man works all his life. It contracts and relaxes from 50 to 150 times per minute. In the systole phase of the heart is reduced, allowing the blood flow and delivery of oxygen and nutrients throughout the body. In the phase of diastole, it is resting. It is therefore very important that the heart beats at regular intervals. If a shorter period of systole, the heart does not have time to fully provide the body with the movement of blood and oxygen. If the reduced period of diastole - the heart has no time to rest.
Irregular heartbeat - a violation rate, rhythm and sequence of contractions of the heart muscle.
The heart muscle - the myocardium consists of muscle fibers. There are two types of fibers:
the working myocardium or contractile, providing reduced conductive myocardium creates an impetus to reduce the working myocardium and provides the holding of this pulse.
Heart muscle is provided by electrical impulses that arise in sinuauricular or sinus node, which is located in the right atrium. Then the electrical impulses are distributed conductive fibers of the atria to the atrioventricular node, located at the bottom of the right atrium. From the atrioventricular node bundle of His starts. He goes to the interventricular septum and divides into two branches - the right and left bundle-branch block. Bundle-branch block, in turn, are divided into small fibers - Purkinje fibers, in which an electrical impulse reaches the muscle fibers. Muscle fibers are reduced by an electric pulse in systole and relax in its absence in diastole. Frequency of normal (sinus) rate reduction of about 50 contractions during sleep in peace, to 150-160 in the physical and emotional stress, limit exposure to high temperatures.
Regulating effect on the activity of the sinus node have an endocrine system, through the blood contained in the hormones and the autonomic nervous system - its sympathetic and parasympathetic divisions. Electrical impulse in the sinus node is due to the difference of concentrations of electrolytes inside and outside the cells and their movement across the cell membrane. The main participants in this process - potassium, calcium, chlorine, and less sodium.
The causes of cardiac arrhythmias are not fully understood. It is believed that the main two reasons are changes in the nervous and endocrine regulation, or functional disorders, and abnormalities of the heart, its anatomical structure - organic disorders. This is often a combination of these root causes.
The increase in heart rate over 100 per minute is called sinus tachycardia. Muscle contraction of the heart with full heart and complexes on the electrocardiogram did not change, just registered a rapid rate. This may be a reaction to a healthy person to stress or physical stress, but can be a symptom of heart failure, various poisoning, diseases of the thyroid gland.
Slowing of heart rate less 60 per minute is called sinus bradycardia. Cardiac ECG complexes are also unaffected. Such a condition can occur in a physically well-trained people (athletes). Bradycardia accompanied as thyroid disease, brain tumors, mushroom poisoning, hypothermia, etc.
Conduction disorders and heart rate - this is a very frequent complication of cardiovascular disease. The most common of the cardiac arrhythmias occur:
arrythmia (an extraordinary reduction) atrial fibrillation (an abnormal rhythm completely) paroxysmal tachycardia (rapid heart rate acceleration from 150 to 200 beats per minute).
Classification of arrhythmias are very complicated. Arrhythmias and blockades can arise anywhere in the cardiac conduction system. From the point of arrhythmias or blockades depends on their appearance.
Arrhythmia or atrial fibrillation, the patient felt a heartbeat, the heart beats more often than usual, or there are interruptions in the heart.
If the patient feels freezing, cardiac arrest and at the same time it happen dizziness and loss of consciousness, the more likely the patient's blockade of the cardiac rhythm or bradycardia (slowing of heart rate).
Upon detection of a patient's cardiac rhythm should conduct a full investigation to clarify the cause of the arrhythmia.
The main method of diagnosis of cardiac rhythm is the electrocardiogram. ECG helps to determine the type of arrhythmia.
However, some arrhythmias occur sporadically. Therefore, for diagnostic use Holter monitoring. This study provides a record of the electrocardiogram in a few hours or days. If the patient has a normal life, and keeps a diary in which notes on the clock they performed the action (sleep, rest, exercise). In deciphering the electrocardiogram ECG data are compared with the diary. Ascertain the frequency, duration, time of occurrence of arrhythmias and their relationship with physical activity, while analyzing the signs of heart failure of blood supply.
Echocardiography can detect diseases contributing to the development of arrhythmias - prolapse valve, congenital and acquired heart disease, cardiomyopathy, etc. Apply more sophisticated methods of investigation: