Atrial fibrillation (AF) is the most common type of cardiac arrhythmia (irregular heart rate or rhythm), and it is the No. 1 cause of stroke, effecting 3.5 million Americans. AF occurs when electrical signals from the heart’s two upper chambers “fibrillate” or quiver.
During each heartbeat, electrical signals spread from the top of the heart to the bottom. The electrical signals begin in a group of cells called the sinus node or sinoatrial (SA) node, which are located in the right atrium. The signals travel from the SA node through the right and left atria, which cause the blood to pump through the ventricles. The signals then move to a group of cells called the atrioventricular (AV) node, which are located between the atria and ventricles. This signal leaves the AV node and travels to the ventricles, causing them to pump blood to the lungs and rest of the body.
Atrial fibrillation occurs when the normal electrical heart impulse is replaced by multiple, rapidly firing signals coming from the pulmonary veins that bring oxygenated blood to the left side of the heart. These signals cause the atria to fibrillate at a rate of 400bpm and bombard the heart’s conduction system, the AV node, with signals resulting in a fast pulse or racing heart. The AV node can’t send the signals to the ventricles fast enough, so as they are beating faster than normal they are not beating in line with the atria. This causes an irregular heartbeat that can cause ventricles to beat 100 to 175 times a minute, which is well beyond the normal 60 to 100 beats a minute.
AF usually causes no symptoms at all. Sometimes they come and go, while other times they are ongoing and permanent. When symptoms do occur, they include:
- Intermittent palpitations
- Trouble breathing
- Chest pain
Treatment for atrial fibrillation can include suppressive therapy with rhythm or rate control medications designed to prevent the attacks, and blood thinning medications to keep the heart from forming blood clots during an event. A curative approach can be achieved with a specialized, catheter-based procedure called an AF Ablation.
At the Ben and Zelda Cohen Heart Rhythm Center, we focus on catheter ablation, a procedure that isolates and permanently prevents these abnormal impulses from triggering this heart rhythm disturbance.
In this video, heart rhythm specialist Dr. Jeffery Banker discusses symptoms and treatment for atrial fibrillation.