Multifocal atrial tachycardia is a rapid heart rate that occurs when too many signals (electrical impulses) are sent from the upper heart to the lower heart.
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.
In multifocal atrial tachycardia (MAT), multiple locations within the heart fire signals at the same time. Too many signals lead to a rapid heart rate -- anywhere from 100 to 250 beats per minute. The rapid heart rate causes the heart to work too hard. If the heartbeat is very fast, the heart has less time to fill up with blood, so it doesn't have the right amount of blood to pump to the brain and the rest of the body.
MAT is most common in people age 50 and over. It is often seen in people with conditions that lower the amount of oxygen in the blood. These conditions include:
You may be at higher risk for MAT if you have:
Additional symptoms that may be associated with this disease:
An examination shows a rapid heartbeat of 100 to 180 beats per minute. Blood pressure is normal or low. There may be signs of poor circulation.
Tests to diagnose MAT include:
Heart monitors are used to record the rapid heartbeat. These include:
If you have a condition that can lead to MAT, that condition should be treated first.
Treatment for MAT includes:
MAT can be controlled if the condition that causes the rapid heartbeat is treated and controlled.
Call your health care provider if:
To reduce the risk of developing MAT, promptly treat the disorders that cause it.