What is Atrial Fibrillation?
Atrial fibrillation (AF or A-Fib) is the most common type of irregular heartbeat, affecting 1-2% of the general population. The prevalence of AF increases with age, and approximately 5-15% of those between 80-90 years of age are affected. Individuals with heart conditions such as pericarditis, cardiomyopathy, abnormal heart valves, or congenital heart defects are at greater risk of atrial fibrillation.
Atrial fibrillation happens when the electrical signals in the heart's upper chambers (atrium) cause the atrium to beat rapidly and irregularly, resulting in an irregularly fast heart rhythm. As a result, the heart may not be able to efficiently pump enough blood around the body or out of the atrium with each heartbeat. If left untreated, atrial fibrillation can lead to heart failure.
Individuals with atrial fibrillation have a five-fold increased risk of experiencing a stroke that can be potentially fatal, as this condition can lead to the formation of blood clots that obstruct the artery responsible for supplying the brain with blood.
Causes of Atrial Fibrillation
- Heart diseases, including heart attacks caused by the blockage of heart vessels, such as coronary artery disease or acute myocardial infarction; abnormal heart valves; heart muscle diseases, such as cardiomyopathy and myocarditis; high blood pressure (hypertension); and irritation of the membrane surrounding the heart (pericarditis).
- Other conditions include an overactive thyroid gland (hyperthyroidism), lung diseases such as emphysema and sepsis, postoperative complications, cerebral hemorrhage, and stroke.
- The causes of some conditions are unknown.
Types of Atrial Fibrillation
- First diagnosed atrial fibrillation: This is the initial diagnosis of atrial fibrillation. If it occurs only once, it is called acute atrial fibrillation, which is a common arrhythmic problem after heart surgery. If it occurs multiple times, it is classified as paroxysmal atrial fibrillation and requires treatment.
- Paroxysmal atrial fibrillation: In this case, the atrial fibrillation starts suddenly and then stops on its own. In most cases of paroxysmal AF, the episodes will stop within 24 hours, although they can last up to 7 days.
- Persistent atrial fibrillation: When the atrial fibrillation lasts for more than 7 days or cannot stop on its own, it is called persistent AF.
- Long standing persistent atrial fibrillation: If the atrial fibrillation lasts for over a year, and the doctor and patient decide to treat the condition and return the heartbeat to normal, it is classified as long-standing AF.
- Permanent atrial fibrillation: If the atrial fibrillation lasts for over a year and the doctor and patient decide not to treat the condition, it is permanent AF.
Symptoms of Atrial Fibrillation
Over half of patients with atrial fibrillation do not show any visible symptoms and are considered asymptomatic. The condition is typically discovered when a patient seeks medical attention for a related complication, such as paralysis of a body part. Patients who do experience symptoms may have the following:
- Palpitations, irregular heartbeat
- Shortness of breath, weakness
- Becoming tired easily during exercise
- Decrease in ability to exercise
- Chest pain
- Lightheadedness
- Difficulty breathing
- Fainting
Tests and Diagnosis of Atrial Fibrillation
- Check heart rate and rhythm
- Perform an electrocardiogram
- Other laboratory tests, including:
- Anemia or kidney function test
- Thyroid function test
- Chest x-ray
- Perform an echocardiography
Treatment Options of Atrial Fibrillation
The main objectives when treating atrial fibrillation are to reduce symptoms and complications, with the ultimate goal of minimizing mortality rates and hospitalization. The specific treatment chosen will depend on factors such as the patient's age, medical history, current symptoms, other medical conditions, and type of atrial fibrillation. There are several options available, including:
- Medications, which can be used to:
- Slow the heart rate (rate control)
- Control the heart's rhythm (rhythm control)
- Reduce the risk of blood clots that can form and cause blockages in any part of the body, but particularly in the brain
- Electrical cardioversion, which is used to restore a normal heart rhythm immediately in urgent situations. However, this procedure cannot prevent the recurrence of atrial fibrillation, and a regular rhythm must be maintained through either long-term medication or ablation.
- Radiofrequency or cryoablation, which can be used to eliminate the abnormal signals that cause atrial fibrillation. This procedure can restore normal heart rhythm immediately and prevent any future recurrence of atrial fibrillation.
