Causes of atrial fibrillation and their prognosis
The most common causes are damage to or impairment of the function of the heart muscle as a result of myocardial infarction, hypertension or cardiomyopathy, as well as valvular heart disease, hyperthyroidism, and SSS. In many cases, AF is idiopathic, i.e. without any obvious reason.
IHD (i.e., stenosing atherosclerosis of the coronary arteries) is not in itself a cause of atrial fibrillation (AF). However, arrhythmia often complicates myocardial infarction in both acute and long-term periods and serves as an indicator of extensive myocardial damage.
Many of the listed causes of atrial fibrillation (AF) can be identified or excluded by clinical examination, ECG and echocardiography. To exclude hyperthyroidism, it is necessary to determine the level of thyroxine and thyroid-stimulating hormone in the serum. If an SSS is suspected, outpatient ECG monitoring may be required.
Prevalence of Atrial Fibrillation (AF)
The prevalence of atrial fibrillation (AF) increases with age. In the UK, when examining male civil servants, FP was found at 0.16, 0.37 and 1.13% of people aged 40–49, 50–59 and 60–64 years, respectively. Among patients monitored by British general practitioners, arrhythmia was detected in 3.7% of patients over 65 years of age.
According to the Framingham study, it was found that 7.8% of men aged 65-74 years suffer from atrial fibrillation (AF). The prevalence of arrhythmias among men aged 75-84 increases to 11.7%. It is estimated that the probability of occurrence of AF in a person’s life is 26%.
Even among those who do not have heart failure and do not tolerate myocardial infarction, this risk is about 15%. In men, arrhythmia occurs 1.5 times more often than in women.
Atrial fibrillation (AF) prognosis
The main factor determining the prognosis is the presence or absence of organic heart disease. For example, with MI, the prognosis is unfavorable, since AF is usually the result of extensive myocardial damage. Many studies have shown that with idiopathic AF, the prognosis is favorable.