Overview
Atrial fibrillation (atrial fibrillation) is a violation of the rhythm of the heart, in which there is no mechanical atrial systole and there is a chaotic electrical activity of their myocardium, the condition is accompanied by irregular contractions of the ventricles and hemodynamic disorders.
Signs of atrial fibrillation on the ECG:
1. The absence of clearly defined p waves with their replacement by fibrillation waves with different amplitudes and frequencies from 350 to 600 per minute. Most clearly, changes are recorded in 1 chest lead (v1);
2. Irregular RR intervals.
The prevalence of atrial fibrillation in the general population is 1 to 2%.
In most cases, the development of fibrillation is associated with organic pathology of the organs of the cardiovascular system, which create a substrate for maintaining fibrillation, however, the appearance of this symptom complex does not always fit into any nosological category, in such a situation they speak of isolated atrial fibrillation.
Diseases that contribute to the occurrence of atrial fibrillation
• Hypertension;
• Damage and malformations of the valvular apparatus of the heart;8/
• Congenital heart defects;
• Chronic ischemic heart disease and acute myocardial infarction;
• Severe chronic cardiovascular insufficiency (stage 2, ii-iv fc);
• Various variants of cardiomyopathy and cardiomyodystrophy (including toxic and alcoholic);
• Hyper- and hypothyroidism;
• Violation of carbohydrate metabolism and diabetes mellitus type 1 and 2;
• Obesity;
• Pickwick's syndrome (sleep apnea);
• Chronic kidney disease.
Lifestyle factors contributing to atrial fibrillation
Certain medications, narcotic substances, tobacco smoking, neuropsychic overstrain, heart surgery, electric shock, and the presence of HIV infection can also provoke atrial fibrillation.
Why is atrial fibrillation dangerous?
Violation can lead to the development of chronic heart failure. Inconsistent contraction of the heart chambers can significantly affect hemodynamics. Lack of coordinated atrial contraction can reduce cardiac output by about 10%. This reduction is usually well tolerated, except in cases of increased ventricular rate, when the rhythm becomes too fast (eg, more than 140 beats/minute) or when patients initially have borderline or reduced cardiac output. Heart failure might result in such circumstances.
Development of acute cerebrovascular accident. The risk of ischemic stroke is 1.5% in people aged 50-59 and 23.5% in people aged 80-89. Particularly dangerous is paroxysmal atrial fibrillation with frequent disruptions of the sinus rhythm. The risk of developing cerebral thrombosis increases especially during the period of disruption and restoration of sinus rhythm. Allocate so-called. Atherothrombotic subtype of acute cerebrovascular accident by ischemic type.