What is atrial fibrillation?
Atrial fibrillation is a quivering or irregular heartbeat, or arrhythmia. Atrial fibrillation, also known as AFib or AF, can lead to blood clots, stroke, heart failure and other heart-related complications.
Learn about AFib
Learn About AFib and Your Heart
AFib can sometimes be felt as a quivering in the chest. Find out what’s happening in your heart during atrial fibrillation and how it can lead to a stroke and other medical problems.
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