Cardiac arrhythmia occurs when your heartbeat is too fast, too slow or irregular. When a heart is in arrhythmia, there may not be enough blood flow throughout the body, causing potential damage to the brain, heart and other vital organs. Arrhythmia can be a symptom of structural heart disease.
In a normal heart, electrical signals run from the upper atria to the two lower ventricles in a regular, repetitive rhythm. This causes the heart muscle to contract from top to bottom and pump blood throughout the body. When these signals are irregular, or arrhythmic, the atria and/or the ventricles can quiver instead of beating normally, affecting blood flow.
Arrhythmias are classified by the speed of the heart rate they cause (fast or slow) and by where they originate (atria or ventricles).
Atrial fibrillation or A-fib is very common, This rapid heart rate is caused by chaotic electrical impulses in the atria. These signals result in rapid, uncoordinated, weak contractions of the atria that in turn produce an irregular, rapid rhythm of the ventricles. Left untreated, a-fib can lead to serious complications such as stroke.
Atrial flutter is similar to atrial fibrillation and can also lead to stroke.
Supraventricular tachycardia refers to many forms of arrhythmia that originate above the ventricles (supraventricular). An example is Wolff-Parkinson-White syndrome, which occurs when you are born with an extra electrical pathway.
Ventricular tachycardia is a rapid, regular heart rate that doesn't allow the ventricles to fill and contract efficiently to pump enough blood to the body. Ventricular tachycardia can often be a medical emergency. Without prompt medical treatment, ventricular tachycardia may worsen into ventricular fibrillation.
Ventricular fibrillation happens when rapid, chaotic electrical impulses cause the ventricles to quiver ineffectively instead of pumping necessary blood to the body. This serious problem is fatal if the heart isn't restored to a normal rhythm within minutes. Most people who experience ventricular fibrillation have an underlying heart disease or have experienced serious trauma, such as being struck by lightning.
Long QT syndrome is a heart disorder that carries an increased risk of fast, chaotic heartbeats. The rapid heartbeats, caused by changes in the electrical system of your heart, may lead to fainting, and can be life-threatening. In some cases, your heart’s rhythm may be so erratic that it can cause sudden death. You can be born with a genetic mutation or heart defect that puts you at risk of long QT syndrome. Several medications may cause long QT syndrome.
Although a heart rate below 60 beats a minute while at rest is considered bradycardia, a low resting heart rate doesn’t always signal a problem. If you’re physically fit, you may have an efficient heart capable of pumping an adequate supply of blood with fewer than 60 beats a minute at rest.
If you have a slow heart rate and your heart isn’t pumping enough blood, you may have one of several bradycardias, including:
Arrhythmias diagnosis has three parts: Information about a patient’s medical and family history, a physical examination and various tests and procedures. A cardiologist or electrophysiologist, a specialist in arrhythmias, usually will coordinate the diagnosis.
Many heart rhythm problems do not require any treatment at all. But some do and treatments can vary depending on the severity of your condition. Options may include: