“The heart has specialized cells that send electrical signals through the heart to produce each heartbeat. These specialized cells work together in an organized way to produce the heart rhythm,” explains Dr. Newton Wiggins, a cardiologist with The Chattanooga Heart Institute at CHI Memorial. “An arrhythmia is an abnormality in the heart rhythm; it is an electrical problem of the heart.”
Dr. Newton Wiggins Cardiologist, The Chattanooga Heart Institute at CHI Memorial
While some forms of arrhythmia make your heart beat too fast, others cause it to beat too slowly. Some arrhythmias even result in an irregular heartbeat. Experiencing one may feel like skipped heartbeats, fluttering, thumping, or racing. But the difference between an arrhythmia and a natural change in heart rate is arrhythmia’s abnormality. For instance, it’s normal, even expected, for your heart rate to increase during exercise, but it shouldn’t happen at rest.
The three most common forms of arrhythmia are bradycardia, tachycardia, and atrial fibrillation. The first, bradycardia, means your heart rate is too slow. It occurs when the electrical signals in your heart slow down or become blocked. Several factors, such as damaged heart tissue, imbalanced chemicals in your blood, and certain medications, can cause bradycardia, and you may experience dizziness, confusion, fatigue, and other symptoms.
Tachycardia is when your heart beats faster than normal while you’re at rest. A typical adult heart rate at rest is somewhere between 60 to 100 beats per minute. With tachycardia, rapid electrical signals take your heart rate much higher. When your heart rate is too high, the heart doesn’t pump blood throughout your body effectively. Your organs can become oxygen deprived, and you could develop shortness of breath, chest pain, or even lose consciousness. It can be caused by a congenital defect, anemia, smoking, and more.
“Atrial fibrillation, a subtype of tachycardia, is the most common arrhythmia,” says Dr. Harish Manyam, director of cardiovascular research and head of the Atrial Fibrillation Center at Erlanger Heart and Lung Institute. “It’s characterized by a rapid, erratic heartbeat.” It occurs when the atria, or upper chambers of your heart, begin to quiver or spasm instead of fully contracting to pump blood into the ventricles, or lower chambers.