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Tell me about the types of irregular heart beat.
Atrial fibrillation is a very common irregular heart rhythm that causes the atria, the upper chambers of the heart, to contract abnormally. Atrial flutter. This is an arrhythmia caused by one or more rapid circuits in the atrium.
How serious is an irregular heart beat?
Coronary artery disease can cause dangerous arrhythmias like atrial fibrillation, or AFib. It's a rapid, quivering heartbeat that can lead to heart palpitations, blood clots, heart attack and stroke.

Question: What are the different types of tachycardia?
Self-contained rewrite: What are the different types of tachycardia?