Atrial Fibrillation Causes

Atrial fibrillation may be associated with various cardiovascular diseases which promote the development of arrhythmia, and its maintenance. Such conditions include:

• Myocardial infarction, which is accompanied by heart muscle damage;
• Arterial hypertension – the frequent increase of the blood pressure;
• Chronic heart failure – the disturbance and worsening of the heart contractile function;
• Coronary artery disease - which is observed in 20% of atrial fibrillation patients;
• Heart defects – both congenital and acquired (mitral valve defect, rheumatic heart disease formed against the background of rheumatism);
• Inflammatory heart diseases – myocarditis, pericarditis;
• Cardio sclerosis – a disease which is accompanied with the formation of scars on the heart;
these scars reduce the heart contractility;
• Sick sinus syndrome.

Also, there are risk factors not connected with any heart pathology, including:

• Hyper-functioning of the thyroid gland – hyperthyroidism, which causes the intoxication with the thyroid hormones called Graves' disease (thyrotoxicosis). The thyroid function abnormality may be the only atrial fibrillation cause and can promote the development of its complications;
• Intoxication caused by the medicine overdose (For example, cardiac glycosides used for the treatment of heart failure), narcotic drugs, smoking, alcohol abuse or excessive coffee consumption;
• Electrolyte imbalance (changes in the potassium, magnesium or calcium blood levels) – hypokalemia (the low level of potassium in blood) as a result of the overuse of diuretic agents or food poisoning;
• Diabetes mellitus – suffering from this condition greatly increases the risk of having atrial fibrillation, especially if a patient also has high blood pressure or obesity;
• Stresses and neuropsychic overstrain;
• Sleep apnea, and particularly in combination with hypertension, diabetes or organic heart diseases, may be a characteristic factor of atrial fibrillation, as apnea causes increased pressure in atria, as well as their enlargement and alterations in the autonomic nervous system state.

Next chapter: Symptoms of atrial fibrillation