Similar term(s): dysrhythmia, irregular heart rhythm.
An arrhythmia (also called dysrhythmia or irregular heart rhythm) is an irregular or abnormal heartbeat.
An arrhythmia can involve a change in the rhythm, producing an uneven heartbeat, or a change in the rate, causing a very slow or very fast heartbeat.
Cleveland Clinic Heart Center
Treating the Heart, Blood Vessels and Circulation
Ventricular fibrillation, for instance, is one of several conditions known as "arrhythmias".
Circulatory system - Pacemaker - Ventricular fibrillation
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