Atrial fibrillation is a pervasive disorder in which the atria of the heart do not contract normally. Learn about its repercussions and how to identify and treat this problem.
Atrial fibrillation is a condition in which the heart’s atria (two of the four heart chambers) do not contract normally. The electrical signal that reaches the atria is irregular, and instead of producing an orderly contraction of the muscle cells, it produces a disorderly contraction. Classically and quite illustratively, it has been described that atrial fibrillation, the atria contract in a similar way as a “bag of worms” would.
The consequence of atrial fibrillation is that there is no effective beat in the atria. This causes blood to remain in the heart and can clot and lead to thrombi. These thrombi can leave the heart and block an artery anywhere in the body, especially when they reach the brain. The obstruction of a cerebral artery by a thrombus that has originated in the heart leads to cerebral infarction or stroke, with very serious consequences.
Another consequence of atrial fibrillation is that the electrical signal that passes from the atria to the ventricles does so quickly and in a disorderly manner. This results in arrhythmia, as ventricular beats occur with an irregular rhythm and faster than usual, called tachycardia.
Atrial fibrillation is a prevalent disease, especially in the population over 65 years of age. It affects 1-2% of the general population. Its prevalence is estimated to double in the next 50 years as the population ages. It is more common in men than women and more common in whites than blacks.
Types of atrial fibrillation
There are two types of atrial fibrillation :
- The paroxysmal atrial fibrillation, which occurs intermittently, with episodes of varying lengths and yields spontaneously.
- The atrial fibrillation chronic or persistent, which is sustained over time and usually not resolved spontaneously. In many cases, paroxysmal atrial fibrillation ends up leading to chronic atrial fibrillation.
The risk of developing atrial fibrillation increases with age. Atrial fibrillation usually appears in people with previous heart disease. The cardiac disorders most frequently associated with the development of atrial fibrillation are:
- Hypertensive heart disease, heart disease due to a chronic increase in blood pressure, puts excessive stress on the heart muscle.
- Diseases of the heart valves that separate the different chambers of the heart. For example, mitral stenosis (narrowing) or mitral regurgitation.
- The insufficient blood supply causes an acute myocardial infarction or ischemic heart disease to the heart.
- Having undergone heart surgery.
- In inflammation of the heart muscle (myocarditis) or the membrane that surrounds the heart ( pericarditis ).
Extracardiac causes can also cause atrial fibrillation:
- Excessive drinking. It usually gives short-term atrial fibrillation. It can occur after a weekend in which alcohol is consumed in excess (holiday heart syndrome or Saturday night heart ).
- The use of drugs that stimulate the heart, such as cocaine or amphetamines.
- Consumption of some medications such as theophylline (used in some lung diseases) or other heart stimulants such as caffeine.
- The hyperthyroidism. Elevation of thyroid hormones causes 5% of cases of atrial fibrillation. In turn, 13% of people with hyperthyroidism suffer from atrial fibrillation. So the possibility of hyperthyroidism should be studied in all people with atrial fibrillation.
- The apnea sleep.