Atrial fibrillation (AFib) can feel quite different from person to person, but common sensations include:

• Palpitations: a fluttering, quivering, pounding, or racing heartbeat, sometimes described as "butterflies," "a fish flopping," or "thumping" in the chest

• Chest discomfort or pressure, which may feel like squeezing or fullness

• Fatigue or extreme tiredness, often the most common symptom, especially in those who don't feel palpitations

• Shortness of breath or difficulty catching your breath, even with mild activity or at rest

• Dizziness, lightheadedness, fainting, or confusion due to reduced blood flow to the brain

• Sweating and weakness

• Anxiety or a strange feeling in the chest, sometimes worse at night

• Some people may feel a sensation like their heart is too big for their chest or that it might jump out

Not everyone with AFib experiences all these symptoms; some may have no noticeable symptoms at all, especially older adults

. Because AFib can increase the risk of stroke and heart attack, any chest pain or severe symptoms should prompt immediate medical attention

. In summary, AFib often feels like an irregular, fast, or fluttering heartbeat accompanied by fatigue, breathlessness, and sometimes chest discomfort or dizziness