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.
An irregular heartbeat is an arrhythmia (also called dysrhythmia). Heart rates can also be irregular. A normal heart rate is 50 to 100 beats per minute. Arrhythmias and abnormal heart rates don't necessarily occur together. Arrhythmias can occur with a normal heart rate, or with heart rates that are slow (called bradyarrhythmias -- less than 50 beats per minute).