Heart palpitations happen when you become aware of your heartbeat in a way that feels abnormal, whether it’s pounding, fluttering, racing, or seeming to skip a beat. Most of the time, palpitations are harmless and triggered by something identifiable like stress, caffeine, or hormonal shifts. But in roughly 37% of people who show up to an emergency department for palpitations, a more serious underlying cause is found, so understanding the full picture matters.
What’s Happening Inside Your Heart
Your heart runs on a precise electrical system that tells each chamber when to contract. A palpitation is what you feel when that timing gets disrupted, even briefly. The most common disruption is a premature ventricular contraction (PVC), where the lower chambers of the heart fire too early. This creates the sensation of a “skipped beat,” though the heart doesn’t actually skip. It contracts prematurely, then pauses slightly longer than usual before the next normal beat. That pause, followed by a stronger-than-normal contraction, is what you feel thumping in your chest.
Similar early beats can originate in the upper chambers too. These premature contractions are extremely common and happen in most people at some point, often without any awareness at all. The difference between someone who notices them and someone who doesn’t often comes down to body awareness, stress levels, and whether other factors are amplifying the irregularity.
Everyday Triggers You Might Not Suspect
Caffeine is the classic culprit, but several less obvious triggers can set off palpitations. Spicy or rich foods can cause heartburn, which sometimes triggers a quickly beating heart because of the proximity of the esophagus to the heart. High-carbohydrate and high-sugar foods can spike your blood sugar, and the subsequent crash is especially likely to cause palpitations if you’re prone to low blood sugar. High-sodium foods, common in processed and canned products, can also play a role.
Chocolate contains a naturally occurring compound from cacao called theobromine that directly increases heart rate. Aged cheeses, cured meats, dried fruit, and alcohol all contain an amino acid called tyramine that raises blood pressure and can trigger palpitations. Even some dietary supplements taken with meals can be responsible, including bitter orange, ginseng, and hawthorn.
Alcohol deserves special attention. Drinking can trigger atrial fibrillation, an irregular rhythm that starts in the heart’s upper chambers and can feel like sustained fluttering or racing. This connection holds even for moderate drinkers and is sometimes called “holiday heart” when it follows a bout of heavier-than-usual drinking.
Nicotine, dehydration, and poor sleep round out the lifestyle triggers. If your palpitations come and go, keeping a simple log of what you ate, drank, and did in the hours before each episode can reveal a pattern surprisingly fast.
Anxiety and the Fight-or-Flight Response
Anxiety is one of the most common reasons people feel their heart palpitate, and the mechanism is straightforward. When you feel uneasy or threatened, your autonomic nervous system activates the fight-or-flight response, flooding your body with adrenaline. This increases your heart rate and the force of each contraction, making you acutely aware of your heartbeat.
The frustrating part is that this can become a feedback loop. You notice your heart beating faster, which makes you more anxious, which makes your heart beat faster still. Panic attacks are especially likely to produce intense palpitations alongside shortness of breath and chest tightness, which can feel alarmingly similar to a cardiac event. If you’ve had palpitations evaluated and they’ve been deemed benign, recognizing the anxiety connection can itself reduce how often they happen. Breathing exercises, regular physical activity, and stress management techniques all help interrupt that cycle at its source.
Hormonal Shifts and Palpitations
Fluctuating hormone levels are one of the most common causes of palpitations in women, particularly during three windows: the days around a menstrual period, pregnancy, and menopause. Big surges in estrogen and progesterone make the heart more sensitive to changes in rhythm. During pregnancy, blood volume increases by nearly 50%, which means the heart has to work harder with every beat, making palpitations more noticeable.
Palpitations during menopause often show up alongside hot flashes and can feel alarming, but they’re typically tied to the hormonal transition rather than to a new heart problem. That said, cardiovascular risk does increase after menopause, so new or persistent palpitations during this stage are worth discussing with a doctor to rule out other causes.
Medical Conditions Beyond the Heart
Not all palpitations originate from a heart problem. An overactive thyroid gland speeds up your metabolism and heart rate, often producing palpitations as one of the earliest noticeable symptoms. Anemia, where your blood carries less oxygen than normal, forces the heart to beat faster to compensate. Electrolyte imbalances, particularly in potassium, magnesium, and calcium, can directly destabilize the heart’s electrical signals and cause irregular or fast rhythms. Dehydration, heavy sweating, vomiting, and certain medications can all throw off your electrolyte balance.
Fever, an overactive adrenal gland, and even some cold medications containing stimulants can trigger palpitations as well. When palpitations are persistent or hard to link to an obvious trigger, these non-cardiac causes are often what testing reveals.
When Heart Conditions Are the Cause
Sometimes palpitations point to a structural or electrical problem in the heart itself. Coronary artery disease, prior heart attack, heart failure, and congenital heart defects can all create conditions where the heart’s electrical signals take the wrong path, producing frequent or sustained irregular rhythms. Scarring from previous heart disease or injury makes the tissue electrically unstable, increasing the likelihood of premature beats and more complex arrhythmias.
Frequent PVCs that happen in isolation are usually benign, but when they become very frequent or occur alongside other heart conditions, they can lead to additional types of irregular heartbeat over time. This is why persistent, worsening, or newly occurring palpitations deserve medical evaluation, particularly if you have known risk factors for heart disease.
Techniques That Can Stop an Episode
If you’re in the middle of a palpitation episode and it feels like a fast or fluttering rhythm rather than chest pain, a set of physical techniques called vagal maneuvers can help. These work by stimulating the vagus nerve, which acts as a brake on your heart rate.
- Valsalva maneuver: Lie on your back, take a deep breath, then bear down as if you’re trying to exhale through a blocked straw, keeping your nose and mouth closed. Hold for 10 to 30 seconds. This is the most widely used technique.
- Diving reflex: Take several deep breaths, hold your breath, and submerge your entire face in a bowl of ice water for as long as you can tolerate. Alternatively, press a bag of ice water or an ice-cold wet towel firmly against your face.
- Coughing forcefully: A hard, sustained cough can sometimes reset the rhythm.
These maneuvers work best for episodes of supraventricular tachycardia, a type of fast rhythm originating above the ventricles. They won’t help with every type of palpitation, but they’re safe to try and can end an episode within seconds.
Signs That Need Immediate Attention
Most palpitations pass on their own and don’t signal danger. But if palpitations occur alongside severe shortness of breath, chest pain, or fainting, that combination requires emergency medical attention. These symptoms together can indicate a dangerous arrhythmia, reduced blood flow to the heart, or another acute cardiac event. Palpitations that last several minutes without letting up, come with lightheadedness that makes you feel like you might pass out, or happen during physical exertion when they never did before also warrant prompt evaluation.
How Palpitations Are Evaluated
Because palpitations are often intermittent, catching them on a test can be tricky. An electrocardiogram (EKG) records your heart’s electrical activity but only captures a snapshot of the moment you’re hooked up. If your palpitations come and go, a Holter monitor, a portable device you wear for 24 to 48 hours, records your heart rhythm continuously so irregularities that happen once or twice a day can be caught. For even less frequent episodes, event monitors can be worn for weeks, recording only when you press a button or when the device detects an abnormal rhythm automatically.
Blood tests for thyroid function, electrolyte levels, and blood count help rule out the non-cardiac causes. If a structural problem is suspected, an echocardiogram (an ultrasound of the heart) can show how well the chambers and valves are working. In many cases, the evaluation is reassuring. The palpitations turn out to be benign PVCs or anxiety-related, and the path forward involves managing triggers rather than treating a heart condition.