Understanding the causes of atrial fibrillation

Atrial Fibrillation – Understanding the Causes 

PREVIOUS                NEXT 

Atrial Fibrillation – Understanding the Causes 

Understanding the causes of atrial fibrillation

The heart consists of four chambers that are important for moving blood around the body. So when blood is returning from other organs in the body to the heart it enters a blood chamber called the right atrium, here the blood collects. When the right atrium is full the blood then enters into the right ventricle and then is sent to the lungs to pick up oxygen. On the return journey the blood collects in the left atrium. Similar to what’s happened in the right atrium previously, blood falls into the right ventricle. When the right ventricle is full the heart muscle squeezes blood from this chamber to go round the body. This provides the body with oxygen for it to survive.

In patients that have atrial fibrillation the atria, ie the top two chambers of the heart do not contract in a regulated manner that I have just described, instead these chambers contract randomly and sometimes at a rate that’s so fast that the heart muscles are unable to relax sufficiently. The consequence of this is that the hearts ability to do its job properly is reduced.

The abnormal contraction of the upper two chambers of the heart is due to electrical impulses inappropriately being sent to the chambers that result in the excessive number of contractions thereby overriding the normal control system which is the Sino Atrial Node. The symptoms of this is the highly irregular pulse rate seen in people with atrial fibrillation.

People who are at greater risk from atrial fibrillation are usually over 65 years of age. Episodes of atrial fibrillation have been associated with situations where somebody may have consumed excessive amounts of alcohol or smoking.

Patients with atrial fibrillation can be grouped into one of four general categories.

The first group is called paroxysmal atrial fibrillation. These Patients that have transient symptoms, ie. Which come and go, and that only last up to 48 hours without the need for treatment. Point to second group is patients that have persistent atrial fibrillation here the symptoms can persist for more than 7 days if left untreated. And the third group of patients are described as having long standing persistent atrial fibrillation. These patients may experience symptoms continuously for a year or more. The fourth population is described as those with permanent atrial fibrillation. As the title states, these patients present with the disorder all the time.

People at risk of atrial fibrillation

It is important to appreciate that atrial fibrillation, affects over a million people in this country, and is the most common heart rhythm disturbance disorder. Although the disorder can present in adults of any age it is more common in older people. Statistics show that 7% of people over 65 have atrial fibrillation and it is more prevalent in men than women.

Patients that have other conditions such as high blood pressure or hypertension, atherosclerosis which is the thickening of the insides of blood vessels, or issues with their heart valves are at greater risk of developing atrial fibrillation.