What causes atrial fibrillation?
The cause of AF is not fully understood and men and women are equally susceptible to the disease. It is also age related – the older you become the more likely you are to develop AF. However, it is noted that AF is more likely to occur in patients who have other heart conditions, such as:
- High blood pressure
- Coronary artery disease
- Mitral heart valve disease(caused by rheumatic heart disease, valve problems at birth, or infection)
- Congenital heart disease (abnormality of the heart since birth)
It can also be associated with:
- Thyroid gland disorders
- Lung cancer and chest infections
- Pulmonary embolism
- Overactive thyroid
- Carbon monoxide poisoning
- Alcohol or drug abuse or misuse
While your risk of developing AF rises with the above mentioned problems, many people devlop AF for no explainable reason. When there is no known cause this is known as 'Lone AF'.
Types of atrial fibrillation
Early on, atrial fibrillation is often intermittent, meaning that it can come and go without warning. There may also be long spells between ‘episodes’. In fact, some people in this early stage of AF may not even be aware they have it, and this 'asymptomatic' AF may only be picked up when they are being tested for another condition.
AF falls into three categories, which also help to describe the progression of the disease.
- Paroxysmal AF – (PAF) episodes that stop within 7 days without treatment;
- Persistent AF – episodes lasting longer than 7 days, or less when treated;
- Permanent or longstanding persistent AF – continuous AF which has occurred for more than one year.