Zipcodes in Twentynine Palms, CA (San Bernardino County) Cities in San Bernardino County, CA. * Not found in the U.S. Census 2000 data. Location may not be an incorporated place or boundary may be approximate.
About Arrhythmia. An arrhythmia is an abnormal heart rhythm. Learn about the heart's structure and why abnormal heart rhythms may cause problems. Read more.
Atrial fibrillation (A-tre-al fi-bri-LA-shun), or AF, is the most common type of arrhythmia (ah-RITH-me-ah). An arrhythmia is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.trial fibrillation (A-tre-al fi-bri-LA-shun), or AF, is the most common type of arrhythmia (ah-RITH-me-ah). An arrhythmia is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.