Atrial fibrillation (also known as AF and AFib) is a condition in which your heart’s atria (the two upper chambers) flutter, or fibrillate. This causes an arrhythmia. To understand how the problem occurs, it’s important to appreciate how your heart functions.
The organ has four chambers: two atria (upper chambers) and two ventricles (lower chambers). Within the right atrium, a group of cells known as the sinoatrial node generates electrical impulses. These impulses spread throughout your atria, causing them to contract. As the contractions cause blood to move from the atria into the ventricles, the impulses travel to the atrioventricular node. This is another group of cells that sits between the ventricles and atria. Once the ventricles fill with blood, the impulses move from the atrioventricular node through the ventricles, causing them to contract.
In AFib, the electrical signals do not start at the sinoatrial node; they start elsewhere. Rather than following the uniform path described above, the signals spread erratically through your atria. That causes them to flutter. Moreover, the signals bombard the atrioventricular node which is unable to transmit the signals to the ventricles as quickly as it receives them. The result is that your atria will fibrillate and your ventricles will beat faster than normal, but your heart’s rhythm will be completely disorganized.
How It Impacts Your Life
Because your ventricles receive a barrage of electrical impulses, they contract more quickly than they should. They do so before they can fill completely with blood. As a result, when they contract, less blood is sent throughout your body. You may experience a shortness of breath, dizziness, and exhaustion after light physical activity.
You’ll also feel your heart beating more quickly and harder than is normal. This is due to the organ working harder to send a sufficient amount of oxygen-rich blood throughout your body.
The most serious complications of atrial fibrillation are stroke and heart failure. Stroke can occur as the result of blood clots that form within the atria, especially the left atrium. If one of the clots moves from the atrium, it can reach a carotid artery and cause a stroke. Heart failure can occur due to your ventricles beating too quickly as the result of receiving a stream of electrical impulses.
How Atrial Fibrillation Is Treated
Atrial fibrillation is not always dangerous. Mild cases may be treated with anticoagulants that will prevent clotting in the atria. However, severe cases are usually best addressed with surgery. Many years ago, open chest surgery was necessary in order for the surgical team to access the heart. Today, AFib can be resolved through a minimally invasive maze procedure.
During maze surgery, a surgeon will create a maze of scar tissue on the atria. The scarred tissue cannot conduct electricity, so the signals are forced to travel along the maze created by the surgeon. This helps to control the impulses and thereby, regulate the heartbeat. If you suffer from AF, ask your doctor whether a maze procedure is a viable solution.