What Are The Different Types Of Abnormal Heart Rhythms?

Dr. Douglas Zipes answers the question: 'Types Of Abnormal Heart Rhythms?'

ByABC News
November 24, 2008, 9:47 AM

— -- Question: What are the different types of abnormal heart rhythms?

Answer :The heart has upper chambers -- the atrium -- and bottom chambers -- the ventricles. And, the different types of arrhythmias can originate in one of those different chambers. So when an arrhythmia starts in the upper chamber, we call that a supraventricular -- simply meaning it's above the ventricles -- abnormal heartbeat. And that can be a very fast heartbeat -- two, three-hundred times a minute -- or it can be an irregular heartbeat so that there are just extra beats associated with it.

And when the arrhythmia originates in the bottom chambers -- the ventricles -- we call that a ventricular arrhythmia. And again, it can be a very fast beat such that it's called a ventricular tachycardia -- 'tachy' meaning fast, -- 'cardia' meaning heart -- so a ventricular tachycardia. And when it gets very fast, we call that fibrillation or ventricular fibrillation, which is responsible for sudden death.

But the bottom chamber can also beat at a irregular basis so that there are just premature beats, and we call those premature ventricular contractions similarly to the upper chamber atrial premature contractions.

So there is a whole range of rapid heartbeats or irregular heartbeats that can occur.

And then finally, the heartbeat can get too slow. That can be due to the pacemaker part of the heart, called the sinus node, that doesn't beat fast enough. Or at times it beats at a normal rate, but the impulse gets blocked from the upper chamber to the bottom chamber and we call that heart block. And that can cause very slow heart rates: 20, 30 beats a minute.