What Does AFib Feel Like?
Key Takeaways: Atrial fibrillation (AFib) is the most common irregular heartbeat, affecting more than 10 million Americans. AFib can feel like a fluttering, pounding, or racing heartbeat, along with fatigue, dizziness, or shortness of breath. Because AFib raises stroke and heart failure risk, early diagnosis and treatment are critical.
Atrial fibrillation, commonly referred to as AFib, is the most common type of irregular heart rhythm, impacting roughly 10.5 million Americans. It causes the upper chambers of the heart to beat chaotically, leading to a fast and irregular pulse. AFib can feel different for everyone – some people notice a fluttering or pounding heartbeat, while others experience shortness of breath, dizziness, or fatigue. Because AFib symptoms often overlap with those of a heart attack, recognizing the differences is critical for seeking timely care.
September is AFib Awareness Month, an event dedicated to raising awareness about this common heart rhythm disorder. In support of this important occasion, South Denver Cardiology would like to devote some time to educating you about some of the more important aspects of this complex condition and the serious issues it can cause.
What Is AFib? Definition & Overview
Atrial fibrillation (AFib) is a type of arrhythmia (irregular heart rhythm) that develops when the heart’s electrical signals misfire. Instead of steady, controlled impulses, the heart sends multiple signals at once, producing a fast, irregular rhythm:
- The upper chambers of the heart (atria) beat chaotically
- They fail to pump blood effectively into the lower chambers (ventricles)
- This disruption can lead to blood clots, stroke, or heart failure if untreated
Common AFib Symptoms
AFib symptoms are different for everyone. Some people notice no symptoms and are only diagnosed during a routine exam, while others experience severe, disruptive episodes.
The most common AFib symptoms include:
Heart-Related Sensations
- Heart palpitations (pounding or racing heartbeat)
- Fluttering or thumping in the chest
- Chest discomfort or pain
Breathing and Energy Issues
- Shortness of breath
- Fatigue and weakness
- Dizziness or lightheadedness
Other Symptoms
- Excessive sweating
- Anxiety
- Fainting or near-fainting
Some people may experience AFib symptoms that come and go. This condition, called paroxysmal atrial fibrillation, can result in symptoms that last anywhere from a few minutes to a few hours. In some instances, you may even experience symptoms for up to a week before your heart returns to a normal rhythm. Other people have more persistent and constant AFib symptoms. In these situations, medical treatment is generally necessary to restore a proper heart rhythm.
Women and older adults often have more subtle symptoms. They may experience weakness and fatigue without the more obvious signs of a heart condition, making it harder to diagnose AFib without a routine checkup.
Are AFib Symptoms Worse at Night?
AFib symptoms at night may feel more intense than daytime episodes. Common reasons include:
- Increased Awareness – Lying still at night makes palpitations easier to notice
- Sleep-Related Triggers – Sleep apnea, poor sleep quality, or sleeping on the left side can trigger episodes
- Greater Intensity – Symptoms like chest fluttering or shortness of breath may feel stronger when resting
How Are AFib Symptoms Different from Heart Attack Symptoms?
AFib and heart attacks share many common warning signs. Some of the overlapping symptoms include:
- Heart palpitations
- Fluttering sensation
- Chest discomfort
- Shortness of breath
- Fatigue
However, heart attacks often involve additional symptoms not typically associated with AFib. A heart attack can cause pain or discomfort in other areas of the upper body, such as your arms, back, jaw, neck or stomach. You may also experience nausea or break out in a cold sweat.
If you’re unsure whether you’re experiencing AFib or a heart attack, seek medical attention immediately.
Is AFib Dangerous?
Yes. While AFib itself is not immediately life-threatening, it increases the risk of serious complications:
- Stroke – AFib increases stroke risk about five times. Blood clots can form in the upper heart chambers, travel to the brain, and block blood flow.
- Heart failure – The heart’s reduced efficiency can weaken its function over time.
- Reduced life expectancy – Untreated AFib can shorten lifespan due to associated risks.
When Should I See a Cardiologist for AFib?
If you’re experiencing AFib symptoms for the first time, you should schedule an appointment with a cardiologist to ensure your condition is properly diagnosed. Since AFib shares common symptoms with other dangerous heart conditions, it’s important to determine whether AFib is the cause and rule out other issues such as heart attack.
If you’re currently managing AFib, you should seek medical attention immediately if you experience the following symptoms:
- Chest Pain – This could be a sign of a heart attack, which would require emergency treatment
- Severe Shortness of Breath – If this symptom comes on suddenly, makes it hard to breathe when resting or becomes worse over time, it may be a sign of a heart attack
- Fainting, Lightheadedness, or Near-Fainting – This may be a sign of low blood flow to your brain, which could be life-threatening
- Sudden Weakness, Numbness or Trouble Speaking/Seeing – These can potentially be symptoms of a stroke, which requires emergency treatment
- Severe Heart Palpitations While Feeling Sick – If your heart is beating extremely rapidly and irregularly (over 120 bpm) and you feel sick, go to the emergency room at once
- Severe Headache, Confusion, or Blurred Vision – These may be symptoms of a stroke
South Denver Cardiology Can Help You Manage AFib
At South Denver Cardiology, we have a dedicated Arrhythmia Clinic to help diagnose and manage a wide range of arrhythmias, including AFib. Our clinic is the premier treatment center for heart arrhythmias in the Denver area. Our team includes some of the most experienced electrophysiologists in the area who can help get your condition under control. Once your AFib is properly managed, we’ll transition you to the care of one of our cardiologists, who will serve as your primary care provider moving forward.
Our comprehensive approach to AFib and arrhythmia treatment is highly effective in:
- Managing symptoms
- Preventing hospitalization
- Preventing stroke
- Treating other contributing health issues
Contact us today to schedule an appointment. South Denver Cardiology serves patients in Denver, Littleton and the surrounding areas.
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