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.
Detailed Synonyms for also known as in English. also known as: also known as adv. also known as so called; alias; known as; named; what they call; going by the name of; also known as; called so called adj. alias adv. known as adj. named adj. what they call adj.
In most cases, you probably want formerly  known as, referring to an old name that is no longer used.  For example, Benin, formerly known as Dahomey, is a country in  Wâ¦est Africa..    In the alternative, formally known  as refers to a fancy name that is usually abbreviated in  ordinary use. For example, The UK, formally known as the United  Kingdom of Great Britain and Northern Ireland, is a country in  Europe..