Many people with A-fib experience a rapid heartbeat, which can make it feel as though the heart is missing a beat or pounding in their chest. Other people may feel dizzy, faint, or inexplicably anxious.
People with A-fib may have difficulty breathing, particularly when lying down.
Most people will have these feelings from time to time, but anyone who notices them happening more regularly, or more intensely, may have A-fib.