Multifocal atrial tachycardia

Definition of Multifocal atrial tachycardia

Multifocal atrial tachycardia is a that occurs when too many signals (electrical impulses) are sent from the upper heart to the lower heart.

Causes, incidence, and risk factors

The human heart gives off electrical impulses, or signals, which tell it to beat. Normally, these signals begin in an area of the upper right chamber called the sinoatrial node (sinus node or SA node). This node is considered the heart’s “natural pacemaker.” It helps control the heartbeat. When the heart detects a signal, it contracts (or beats). The normal heart rate in adults is about 60 to 100 beats per minute. The normal heart rate is faster in children.

Signs and tests

An examination shows a rapid heartbeat of 100 to 180 beats per minute. is normal or low. There may be signs of poor circulation.


If you have a condition that can lead to MAT, that condition should be treated first.

Expectations (prognosis)

MAT can be controlled if the condition that causes the rapid heartbeat is treated and controlled.


Issam Mikati, MD, Associate Professor of Medicine. Feinberg School of Medicine, Northwestern University, Chicago, IL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 5/4/2010

Heart, section through the middle
Heart, front view

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