Atrial fibrillation (a-FIB) is the most common abnormal heart rhythm that occurs in 1 — 2% of the population of the globe. The frequency of occurrence strongly depends on age, younger than 40 years is 0.5% of the population over 65 is 5%, and those who are over 80 — 10%.
The pathogenesis of the disease is the changes in the automaticity of the myocardial cells, in which the sinus node ceases to be the main source of the cardiac rhythm. In this pathology in the muscle tissue of the Atria is generated pathological nerve impulses that guide the heart. It is believed that when atrial fibrillation occurs from 350 to 800 signals per minute.
The content of the article
The name of the disease was due to its specific reflection on the ECG, where instead of teeth P rasenanlage appear asymmetric f waves with very high frequency. Looking at them the impression of atrial fibrillation.
The differences in the generation of electrical impulses in a healthy heart and the atrial aritmeettisia disease
Atrial fibrillation, like any other disease, can develop on the background of existing pathology. The major diseases-predecessors include:
- CHD (coronary heart disease);
- defects of the mitral valve (located between the left atrium and ventricle);
- syndrome WPW (Wolff-Parkinson-white);
- SSSU (sick sinus syndrome node);
- arterial hypertension;
- diabetes mellitus;
- alcoholic myocardial (heart damage due to constant use of alcohol);
- electrolyte deficit – in most cases — the lack of magnesium and potassium.
Often provoke an attack of atrial fibrillation can:
- increased physical load or emotional arousal;
- alcohol, coffee;
- a rich meal.
Rarely the cause of the disease and trigger factors cannot detect. In this case, atrial fibrillation is considered to be idiopathic.
A major role in the pathology plays a nervous system. Increased tone a specific Department can provoke attacks. Vagal type of atrial fibrillation developed with the active influence of a parasympathetic link. The sympathetic division causes hyperadrenergic atrial fibrillation.
The mechanism of development of atrial fibrillation Disease occurs when the heterogeneity of the myocardium of the Atria. Because of this, in certain parts of the muscle appear the pathological lesions of generating nerve signals. In contrast to flutter, in this case, is the place to be not one or two focus, and their much greater number. As a result of the conduction of excitation from all these sources in the myocardium of the Atria occurs uncoordinated and ineffective contraction of the latter.
In case, if all the pulses are transmitted to the lower divisions, then the ventricles would be decreasing by analogy with atrial fibrillation: would develop ventricular fibrillation. This would lead to violation of the ejection of blood from the heart and death.
To prevent such a situation conducting system of the heart with a special “filter”. As it stands atrioventricular node, located between the Atria and ventricles. Thanks to this special structure, the delay excess number of nerve signals and the frequency of contractions of the ventricles is significantly below that of the Atria. This protects the body from sudden death with ventricular fibrillation.
Depending on the mechanism of occurrence, as mentioned above, there are two types of atrial fibrillation:
Characterization of the vagal type of atrial fibrillation:
- occurs more often in the male half of the population;
- the attacks begin when eating or at night;
- there is no dependence on physical load or stress;
- triggers can be tightly knotted necktie or the scarf, the rest or the horizontal position of the body, strongly tightened belt or bloating.
Hyperadrenergic variant is characterized by:
- the occurrence of seizures at any time of the day, rarely at night;
- the dependence of attack from physical or emotional condition;
- frequent occurrence in women.
In the course of the disease can have the following forms:
- Permanent chronic atrial fibrillation without sinus rhythm.
- Paroxysmal periodic “breakdowns” of the rhythm, and then recover.
Clinical manifestations the symptoms of atrial fibrillation
The peculiarity of this variant of development of atrial fibrillation is the alternating normal functioning of the heart with the leading source of rhythm of the sinus node and atrial fibrillation. The frequency of attacks may vary from one lifetime to several in a day. Sometimes this form eventually becomes constant.
In this embodiment, the arrhythmia out of the attack due to the normal functioning of the heart the person feels as usual. During the sharp rhythm disorders by type of atrial fibrillation, the condition is deteriorating. When self-medication or restoring normal heartbeat feeling becomes normal again.
When the occurrence of the attack (paroxysm) of atrial fibrillation the heart begins to contract ineffectively and quickly. The result is inadequate blood pumping and deliver it to vital organs. This leads to ischemia of tissues and body systems.
With frequent paroxysms or prolonged periods (episodes) irregular heartbeat the entire body gradually adapts to the work of the heart. Subjective health is deteriorating at the time of the transition to arrhythmia from normal sinus rhythm. During the already disturbed rhythm of the human condition and his feelings a little better.
Atrial fibrillation can manifest totally different symptoms. Common of which are:
- attack sudden palpitations;
- unpleasant sensations in the heart region;
- severe weakness, malaise;
- excessive sweating, cold extremities;
- the feeling of fear;
- dizziness up to loss of consciousness.
The above symptoms can disturb a person not only in atrial fibrillation. Almost all types of cardiac arrhythmias are accompanied by similar manifestations.
A permanent form
This condition of atrial fibrillation is characterized by lack of impulse generation in the sinus node. All idiopathic springs rhythm is located in the myocardium of the Atria. Paroxysmal form often becomes permanent. This happens either if you cannot restore sinus rhythm, or when too frequent paroxysms, when the restoration of normal heartbeat is not justified.
Condition, and symptoms in this embodiment, flow is determined by the heart rate (HR). If it is as close to 80 beats per minute, then the person might not even feel at this disease. With significantly increased or decreased heart rate health is deteriorating.
The concept of “heart rate in atrial fibrillation” is the number of contractions of the ventricles per minute. In this pathology to change the number of atrial is not possible.
Diagnosis of atrial fibrillation
Normal sinus rhythm and atrial fibrillation on ECG the Main methods to detect atrial fibrillation is an ECG examination and Holter monitoring. An important criterion for diagnosis and further treatment is heart rate at rest. This value is the starting point in selecting the dosage of the drug. Sometimes it is important to know the frequency with which the heart is reduced during exercise. For this additionally appointed the stress test.
Interpreting ECG diagnosis atrial fibrillation can be put under the following changes:
- There is no single prong P.
- Instead of them registered the waves of fibrillation f.
- Different amplitude and ventricular complexes QRS.
- QRS complexes are located at different distances from each other (uneven R-R).
All these data testify about the defective contraction and relaxation of individual myocardial fibers of the Atria.
Treatment option of the disease depends on the course and severity of developing complications. Permanent form does not require restoration of normal heartbeat and involves the correction of heart rate and increase contractility of the ventricles. Paroxysmal form requires the restoration of sinus rhythm as soon as possible.
The treatment of paroxysmal atrial fibrillation (stopping of the attack in paroxysmal form):
- To provide access of fresh air.
- To take a horizontal posture.
- Make The Sage. If an attack developed not for the first time to accept the doctor recommended anti-arrhythmic drug.
- In the case of a sharp deterioration or lack of effect within a few hours, you should seek qualified medical help.
Assistance in hospital, the restoration of the rhythm is made in two main ways:
- Introduction of antiarrhythmic drug intravenously.
- The use of electro therapy (using electric discharge).
The choice of tactics of treatment of the permanent form of atrial fibrillation should be treated with caution. In some cases it can go on and on restoring normal sinus rhythm.
The main task of permanent treatment arrhythmia – ensuring adequate blood supply to all organs of the body. You need to create the optimal heart rate. At high frequency using drugs, which contribute to the atrioventricular node to pass to the ventricles smaller number of nerve impulses. When the frequency of ventricular contraction is less than 40 beats per minute medical treatment is practically useless. In this case surgical intervention is necessary. Due to the increased risk of blood clots in the cavities of the Atria additional therapy aimed at prevention of their occurrence.
The main drugs used in atrial fibrillation:
- Antiarrhythmic drugs (Procainamide, Amiodarone).
- Beta-blockers (Inderal, Metoprolol).
- Calcium channel blockers (Verapamil).
- Antiplatelet Agents (Aspirin, Procard).
- Minerals and trace elements – compounds containing potassium and magnesium (Asparkam, Magnetic, Panangin).
- Cardiac glycosides (prescribed for accession of heart failure – Digoxin, Strophanthin).
Surgical treatment of the disease
In view of active development of science and medicine, surgical method for the treatment of arrhythmias is very promising. There are several different approaches:
- The physical destruction element of the atrioventricular node or bundle of pathological conduct nerve impulse to the ventricles from the atrium. This option is resorted to in the absence of effect from drug treatment. The operation resulted in the decrease in the heart rate is achieved by normalizing the number of signals to the ventricles. Quite often atrioventricular connection is completely blocked, and for the normal contraction of the ventricles they implanted a pacemaker (IVR – artificial pacemaker).
- Implantation of mini-defibrillator-cardioverter. This treatment option is more suitable for people who have paroxysms of atrial fibrillation are infrequent. This device automatically detects arrhythmias and produces an electrical impulse to restore normal heart activity.
Prevention of atrial fibrillation
If you have a history of at least one episode of paroxysmal atrial fibrillation it is important to identify its cause. This is necessary to prevent re-occurrences. The General plan of measures aimed at the prevention of arrhythmia:
- Treatment of diseases caused by a rhythm disturbance.
- Supplementation of magnesium and potassium. Eating foods rich in their content (pumpkin, watermelon, bananas).
- Continuous administration of small doses of antiarrhythmic agents (only on the advice of a cardiologist).
- Elimination of the influence of the high tone of the nervous system.
The last paragraph of effective prevention if there is evidence that vagal or hyperadrenalism arrhythmia.
Preventing attacks vagal type of atrial fibrillation:
- reduction of overweight;
- avoidance of constipation and bloating;
- the exclusion of horizontal body position after eating. The exception of excessive eating at night;
- avoiding abrupt bending of the trunk.
Prevention hyperadrenergic type:
- the increase in time of rest and sleep;
- avoiding stress and heavy physical exertion;
- the maximum decline in the consumption of coffee, strong tea, nicotine;
- receiving sedative herbal medicines (tincture of motherwort or Valerian).
Speaking about the possible complications of atrial fibrillation, you need to understand that they are divided into two types:
- When developing the paroxysm.
- Developing in the long standing arrhythmia.
The first group includes:
- OLIN – acute left ventricular failure (cardiogenic pulmonary edema);
- Stroke – acute impairment of cerebral circulation due to a lack of oxygen and nutrients;
- infringement of blood supply of any organ of the body.
The second group includes the so-called late complications:
- chronic heart failure in all its manifestations;
- increased blood clots and thrombosis in various organs (myocardial infarction, thromboembolic strokes).
Prediction of atrial fibrillation
The prognosis of the disease fully depends on timely diagnosis and treatment of diseases. Appropriate treatment, promotes normalization of heart rate and proper blood supply of the organs of the body, in the least degree leads to complications. However, even with proper treatment there is an increased risk of thrombosis and their complications.
Thus, in atrial fibrillation it is possible to maintain a normal lifestyle for a long time.