Cardiac dysrhythmia, also called cardiac arrhythmia, is common, particularly as people age. It can occur in a healthy heart and is not necessarily a major concern. However, it can be an indication of a more dangerous, potentially life-threatening problem.

Definition

Arrhythmia is a condition in which the heart displays abnormal electrical activity. It can happen as a result of health issues, such as heart disease, or may be a temporary condition caused by an outside factor, like excess caffeine consumption.

Causes

Arrhythmia occurs when the heart develops an abnormal rhythm; it may be caused from scarring of the heart tissue, heart disease, high blood pressure, diabetes or an overactive thyroid gland.

Outside Causes

A person with a normal, healthy heart may experience arrhythmia from triggers such as smoking, too much alcohol or caffeine, drug abuse, stress, medications or dietary supplements and herbal treatments.

Types of Arrhythmias

Bradycardia (too slow a heartbeat) and tachycardia (too fast a heartbeat) can both be caused by problems with the heart's natural pacemaker or with the heart's conduction. Atrial fibrillation, a quivering heartbeat, is caused when the parts of the heart's atria emit uncoordinated electrical signals. Premature ventricular contraction, which feels like a skipped heartbeat, occurs when an extra beat comes sooner than normal--it may have no cause or be caused by disease or injury to the heart.

Other Rhythm Disorders

In Adams-Stokes Disease a normal heartbeat is interrupted, causing a heart block. Atrial flutter, a fast, steady heartbeat, usually caused by heart disease, chronic obstructive pulmonary disease or as a result of open-heart surgery. In sick sinus syndrome or sinus arrhythmia, the heartbeat changes in rate from fast to slow. In Wolff-Parkinson-White syndrome, the heart's electrical signal ricochets between the atria and ventricles, causing a fast heart rate.

Source:

American Heart Association: Types of Arrhythmias

Mayo Clinic: Heart Arrhythmias: Causes

Mayo Clinic: Heart Arrhythmias: Symptoms