An irregular heartbeat most commonly feels like a fluttering, pounding, or racing sensation in your chest. Many people describe it as a “skipped beat,” a sudden thud, or a brief flip-flopping feeling behind the breastbone. These sensations are called palpitations, and they’re one of the most common reasons people visit a primary care provider, accounting for roughly 16% of visits in one study.
Common Sensations and What Causes Them
The most frequently reported feeling is a skipped beat, but your heart doesn’t actually skip anything. What happens is that your heart fires an extra beat slightly early, then pauses briefly before the next normal beat. During that pause, your heart fills with more blood than usual. The beat that follows is extra forceful because of all that extra blood, and that strong thump is what you actually feel. So the sensation of a “skip” is really the contrast between a quiet early beat and the heavy one that comes after it.
Other common descriptions include:
- Fluttering: a light, rapid quivering in the chest, sometimes extending into the throat or neck
- Pounding or thumping: a hard, noticeable beat that feels like your heart is hitting your chest wall
- Racing: a sudden burst of fast heartbeats that may come on without any physical exertion
- Flip-flopping: the sensation that your heart turned over or did a somersault
Some people notice these feelings in their chest, while others feel them more in their throat or even their stomach. You might notice them more at night when you’re lying quietly in bed and there’s less sensory distraction. The intensity varies widely. For some people the sensation is barely noticeable, while for others it’s startling enough to cause a jolt of adrenaline, which can then make the feeling worse.
Symptoms That Can Come Along With It
An irregular heartbeat doesn’t always arrive alone. Depending on what’s causing the rhythm change, you might also experience lightheadedness or dizziness, shortness of breath, chest tightness or pressure, or a general feeling of fatigue. Brief, isolated palpitations without any of these additional symptoms are usually benign. When the rhythm disturbance is more sustained, though, your heart may not pump blood efficiently enough, which is what produces those secondary symptoms.
Anxiety Palpitations vs. a Heart Problem
This is the distinction most people searching this topic really want to understand. Anxiety and panic attacks can produce palpitations that feel identical to a cardiac arrhythmia: the same racing, pounding, and chest-tightening sensations.
A few patterns help separate the two. Palpitations caused by anxiety tend to start suddenly, coincide with feelings of stress or panic, and resolve within a few minutes once you calm down. They come and go quickly. Palpitations from a heart rhythm problem are more likely to occur without an obvious emotional trigger, last longer than a few minutes, happen repeatedly over days or weeks, or occur during rest or sleep.
Neither of these patterns is a perfect diagnostic rule. Sometimes anxiety triggers a real arrhythmia, and sometimes a sudden arrhythmia triggers anxiety. The key signal worth paying attention to is sustained palpitations combined with chest pain, trouble breathing, dizziness, or confusion. That combination warrants immediate medical attention regardless of whether anxiety is also present.
Common Triggers
Many people notice palpitations only in specific situations. Caffeine is one of the most common triggers. It stimulates your nervous system and can cause your heart to race, your blood pressure to rise, and your rhythm to become irregular. If you notice your heart pounding after coffee, energy drinks, or even chocolate, caffeine sensitivity is a likely contributor. Alcohol, nicotine, decongestants, and some supplements (especially those containing stimulants) can produce similar effects.
Beyond substances, dehydration, poor sleep, intense exercise, and hormonal shifts (particularly during menstruation, pregnancy, or menopause) can all trigger episodes. Thyroid problems, especially an overactive thyroid, are another well-known cause. Sometimes identifying and removing a trigger is all it takes to stop the episodes entirely.
How Doctors Capture What You’re Feeling
The tricky part about diagnosing an irregular heartbeat is that it often isn’t happening when you’re sitting in a doctor’s office. A standard electrocardiogram (EKG) only records a few seconds of your heart’s rhythm, so if your palpitations are intermittent, it may look completely normal.
That’s where wearable heart monitors come in. These are small devices, often smaller than a deck of cards, that record your heart’s electrical activity over a longer window. A Holter monitor records continuously for 24 to 48 hours and works well if your symptoms are frequent. If your episodes are more sporadic, your doctor may use a patch recorder that sticks to your chest and monitors for up to two weeks, or a loop memory monitor that you activate when symptoms start. The loop recorder captures not just the moment you press the button but also a minute or two before and after, which helps catch the beginning of an episode you might not have noticed right away.
For people whose episodes are very rare, there are implantable loop recorders that sit just under the skin and monitor for years. Some consumer smartwatches can also record a basic EKG tracing, which can give your doctor useful data if you happen to capture an episode at home. The goal with all of these tools is the same: to match what you’re feeling to what your heart is electrically doing at that exact moment.
What’s Considered Normal
Nearly everyone experiences occasional premature heartbeats. They’re so common that most cardiologists consider them a normal variant, especially in people under 50 with no underlying heart disease. Having a handful of skipped beats per day, or even a few dozen, is generally not cause for concern if they come and go and aren’t accompanied by fainting, chest pain, or prolonged episodes of racing.
The line between “normal quirk” and “worth investigating” depends on frequency, duration, and context. Palpitations that last only a second or two and happen a few times a week are very different from episodes that last minutes, happen daily, or leave you lightheaded. Sustained palpitations alongside chest pain, breathlessness, fainting, or confusion represent the clearest signal that something beyond a benign extra beat is going on.