Heart palpitations are the conscious awareness of your own heartbeat, and in most cases they signal something temporary and harmless rather than a serious cardiac problem. You might feel a flutter, a skipped beat, a sudden pounding, or a racing sensation in your chest, neck, or throat. While palpitations can be unsettling, they are one of the most common reasons people visit a doctor for a heart-related complaint, and the vast majority trace back to benign causes like stress, caffeine, or isolated extra beats that the heart produces routinely.
What You Are Actually Feeling
Most of the time, the sensation people describe as a “skipped beat” is not a beat that failed to happen. It is a premature beat followed by a slightly longer pause. The heart’s upper chambers (atria) or lower chambers (ventricles) fire a fraction of a second earlier than expected, then the heart compensates with a brief pause before the next normal beat. That pause, and the stronger-than-usual beat that follows it, is what you feel. These premature contractions come in two varieties: premature atrial contractions (PACs), which originate in the upper chambers, and premature ventricular contractions (PVCs), which originate in the lower chambers. PVCs tend to feel more dramatic because the ventricles are responsible for the heart’s main pumping action, producing a wider, more forceful beat that stands out from the normal rhythm.
Nearly everyone has occasional PACs and PVCs. They happen dozens or even hundreds of times a day in many people without ever being noticed. Awareness tends to spike during quiet moments, especially lying in bed at night, when there are fewer distractions competing for your attention. The palpitation is not the extra beat itself but your perception of it, which is why the same number of premature beats can feel alarming to one person and go completely unnoticed by another.
Stress, Adrenaline, and the Fight-or-Flight Response
Emotional and physical stress rank among the most common triggers. When you are anxious, frightened, or under pressure, your sympathetic nervous system floods the bloodstream with catecholamines, the family of hormones that includes adrenaline and noradrenaline. At low levels, these hormones simply speed up the heart and make it beat harder, which is useful if you need to run from danger. At higher levels, they can push calcium into heart muscle cells faster than normal, destabilizing the electrical signals that keep the rhythm steady and making premature beats more likely.1PubMed. Role of the excessive amounts of circulating catecholamines and glucocorticoids in stress-induced heart disease
This is one reason palpitations tend to cluster around stressful life events, sleep deprivation, or periods of burnout. The heart itself is structurally fine; the chemistry around it is just temporarily out of its comfort zone. For many people, reducing stress through exercise, sleep hygiene, or even slow breathing exercises can noticeably reduce how often palpitations occur, because those interventions dial down the catecholamine surge at its source.
Caffeine, Alcohol, and Other Substances
Caffeine is the substance people most often blame for palpitations, and the relationship is more nuanced than the usual advice to “cut back on coffee” suggests. Caffeine blocks adenosine receptors in the heart, inhibits certain enzymes involved in electrical signaling, and triggers a small release of catecholamines, all of which can theoretically promote irregular beats.2PubMed Central. Caffeine and Arrhythmias: A Critical Analysis of Cardiovascular Responses and Arrhythmia Susceptibility In practice, though, large population studies have found that moderate coffee consumption does not meaningfully change the heart’s electrical timing. In one analysis using data from the Third National Health and Nutrition Examination Survey, even people drinking six or more cups of coffee a day showed no significant shift in the electrical interval that governs heartbeat timing compared to non-drinkers.3PLoS ONE. Coffee, Alcohol, Smoking, Physical Activity and QT Interval Duration: Results from the Third National Health and Nutrition Examination Survey That does not mean caffeine can never trigger palpitations in a given individual, but it does mean the average person does not need to give up coffee as a first response.
Alcohol is a somewhat different story. Heavy or binge drinking has a clearer link to rhythm disturbances. The same survey data showed that binge drinkers had a modest but real prolongation of the QT interval compared to non-drinkers, a change that reflects slower electrical recovery and can set the stage for extra beats or more sustained rhythm problems.3PLoS ONE. Coffee, Alcohol, Smoking, Physical Activity and QT Interval Duration: Results from the Third National Health and Nutrition Examination Survey The phenomenon of palpitations or atrial fibrillation after a night of heavy drinking is common enough that clinicians sometimes refer to it informally as “holiday heart.” Nicotine, stimulant medications, decongestants containing pseudoephedrine, and recreational stimulants can all produce similar effects through their own catecholamine-boosting pathways.
The Anxiety Feedback Loop
One of the trickiest aspects of palpitations is how easily they feed on themselves. You notice an unusual heartbeat, your brain interprets it as a possible sign of danger, your anxiety rises, your heart rate increases in response, and the faster heart rate makes you notice even more beats. Researchers have documented this cycle in patients with panic disorder, showing that even small increases in heart rate can be perceived as catastrophic, which triggers more anxiety and further increases in heart rate.4PubMed. Anxiety induced by cardiac perceptions in patients with panic attacks: a field study
This feedback loop means that anxiety disorders are one of the most common non-cardiac causes of palpitations. People who are highly attuned to their own body sensations, a trait psychologists call interoceptive sensitivity, are more likely to notice benign rhythm variations that most people would ignore. For these individuals, cognitive behavioral therapy or other anxiety-focused treatments can be more effective at reducing palpitation symptoms than cardiac medications, because the problem was never really the heart.
Thyroid and Hormonal Influences
If your palpitations are persistent and come with weight loss, heat intolerance, tremor, or feeling wired despite being exhausted, an overactive thyroid gland may be the culprit. Excess thyroid hormone directly affects heart muscle, increasing both the rate and force of contraction and making rhythm disturbances more likely. Atrial fibrillation and sinus tachycardia are the most common arrhythmias linked to hyperthyroidism, and excess thyroid hormones are associated with significantly increased cardiovascular risk.5PubMed Central. Hyperthyroidism and the Risk of Cardiac Arrhythmias: A Narrative Review A simple blood test for thyroid function is one of the first things doctors check when palpitations are a new complaint, because treating the thyroid problem usually resolves the heart symptoms entirely.
Other hormonal shifts can produce palpitations too. Menopause-related changes in estrogen levels are a common trigger, and pregnancy deserves its own discussion (see below). Even the hormonal fluctuations of the normal menstrual cycle can cause transient palpitations in some people, particularly in the luteal phase when progesterone peaks.
Electrolyte Imbalances
Your heart’s electrical system depends on a precise balance of minerals, especially potassium and magnesium. When either runs low, the electrical properties of heart muscle cells change. Magnesium deficiency is particularly sneaky: without enough magnesium, cells struggle to hold on to potassium, because magnesium is needed for the pump that moves potassium into cells and sodium out. The result is a cascade of electrical instability that can manifest as premature beats or even more sustained arrhythmias.6PubMed. Relation between potassium, magnesium and cardiac arrhythmias
Common situations that deplete these minerals include heavy sweating, chronic diarrhea or vomiting, certain diuretic medications, and diets very low in fruits and vegetables. If you have been experiencing frequent palpitations and any of those apply, getting your electrolyte levels checked is a straightforward and often revealing step. Correcting a deficiency can stop palpitations within days.
The Gut Connection
This one surprises most people: palpitations can sometimes originate not from the heart but from the digestive tract. The vagus nerve, which runs from the brainstem down through the chest and into the abdomen, serves as a communication highway between the gut and the heart. Conditions like a hiatal hernia or severe gastroesophageal reflux can physically irritate the vagus nerve or press on structures near the heart, triggering rhythm disturbances. In one documented case, a patient with worsening palpitations linked to eating was found to have a high burden of PVCs caused by a hiatal hernia and reflux disease. After surgical correction of the hernia, the arrhythmia resolved completely.7PubMed Central. Rare and unusual presentation of gastrocardiac syndrome
If your palpitations reliably follow meals, especially large meals or meals that trigger acid reflux, and your cardiac workup comes back clean, this gut-heart interplay is worth investigating. Treating the reflux or hernia is far more effective than treating the arrhythmia in these cases, because the heart is responding to a stimulus rather than malfunctioning on its own.
Palpitations During Pregnancy
Pregnancy increases blood volume by roughly 40 to 50 percent, raises the resting heart rate, and reshapes the hormonal environment in ways that all promote palpitations. This makes rhythm awareness extremely common among pregnant individuals, and it is one of the most frequent cardiac complaints during pregnancy. Most of the time the palpitations are benign, driven by the same premature beats that happen in everyone, just amplified by the physiological demands of growing a fetus.
However, people with pre-existing structural or functional heart abnormalities face a genuinely increased risk of developing more serious arrhythmias during pregnancy, because the cardiovascular adaptations of pregnancy can unmask or worsen underlying conditions.8PubMed Central. Clinical approach to palpitations in pregnancy This is why palpitations in pregnancy should always be mentioned to a healthcare provider, even when they feel mild. In most cases the evaluation will be reassuring, but for the subset of people with undiagnosed valve problems or inherited rhythm disorders, pregnancy may be the first time the condition becomes apparent.
When Palpitations Are a Warning Sign
The overwhelming majority of palpitations are benign, but there are specific red flags that shift the picture. You should seek prompt medical attention if palpitations come with any of the following:
- Fainting or near-fainting: Losing consciousness or feeling like you are about to pass out suggests the heart’s rhythm is disrupting blood flow to the brain.
- Chest pain or pressure: This combination raises the possibility of coronary artery disease or another structural problem.
- Severe breathlessness: Difficulty breathing during palpitations may indicate a sustained arrhythmia that is compromising the heart’s pumping ability.
- Prolonged rapid episodes: A heart rate that suddenly jumps above 150 beats per minute and stays there for minutes or longer warrants evaluation, especially if it starts and stops abruptly.
Patients with palpitations accompanied by dizziness, excessive fatigue, or chest pain need acute stabilization and often referral for further workup.9PubMed Central. Palpitations: Evaluation and management by primary care practitioners A personal or family history of sudden cardiac death, inherited rhythm disorders, or structural heart disease also raises the stakes and warrants earlier and more thorough investigation, even if the palpitations feel similar to the benign variety.
How Doctors Investigate Palpitations
The challenge with diagnosing palpitations is that they are often intermittent. A standard 12-lead ECG in the doctor’s office captures about 10 seconds of heart rhythm, which is helpful only if the abnormal rhythm happens to be occurring right then. A traditional 24-hour Holter monitor extends the window but still misses events that happen less than once a day.
Longer-term monitoring has proven substantially more effective. In a head-to-head comparison, seven-day continuous ECG patches detected arrhythmias in about 35 percent of patients, compared to 19 percent with standard 24-hour Holter monitors.10PubMed Central. The efficacy of detecting arrhythmia is higher with 7-day continuous electrocardiographic patch monitoring than with 24-h Holter monitoring For events that are even less frequent, implantable loop recorders can sit under the skin and record heart rhythm continuously for up to three years.
Beyond rhythm monitoring, doctors typically check blood work for thyroid function, electrolytes, and anemia. An echocardiogram may be ordered to look at the heart’s structure, particularly if there is a murmur or other clue pointing to a valve problem. The diagnostic workup is graduated: the more red flags present, the more extensive the testing.
What Smartwatches Can and Cannot Tell You
Consumer wearable devices have become surprisingly capable at detecting certain arrhythmias, particularly atrial fibrillation. Meta-analyses have found that smartwatch-based detection achieves roughly 96 percent sensitivity and 94 percent specificity for atrial fibrillation, which puts it in the same neighborhood as some medical-grade monitors.11American College of Cardiology. Smartwatches and Atrial Fibrillation: What Works and What Needs Improvement? For someone with infrequent but symptomatic episodes, the ability to capture a rhythm strip at the moment you feel something odd can be genuinely useful.
The limitation is that smartwatches are optimized for atrial fibrillation and tend to be less reliable for other types of arrhythmia. They can also generate false alarms, especially during exercise or when the watch shifts on the wrist, and a single-lead wrist tracing does not provide enough information for a definitive diagnosis. Think of a smartwatch notification as a reasonable prompt to schedule a medical evaluation, not as a diagnosis in itself.
The Reassuring Long-Term Picture
Perhaps the most important thing to know is that in people with structurally normal hearts, even frequent premature beats carry little long-term risk. A study following apparently healthy adults aged 60 and older found that having 100 or more premature ventricular beats in 24 hours, or even runs of repetitive extra beats, did not predict a higher rate of future coronary events compared to people without those beats.12The American Journal of Cardiology. Long-term prognostic significance of ambulatory electrocardiographic findings in apparently healthy subjects ≥60 years of age Similarly, research on otherwise healthy volunteers found that frequent or repetitive ventricular extra beats triggered by exercise did not predict increased heart-related illness or death over a follow-up period averaging more than five years, and none of the study subjects ended up needing anti-arrhythmic drugs.13Journal of the American College of Cardiology. Prevalence and long-term significance of exercise-induced frequent or repetitive ventricular ectopic beats in apparently healthy volunteers
These findings matter because the fear of what palpitations might mean often causes more distress than the palpitations themselves. Once structural heart disease has been ruled out, you can generally regard isolated extra beats as a quirk of the heart’s electrical wiring rather than a sign of something dangerous. Treatment focuses on managing symptoms and triggers rather than eliminating every premature beat, since those beats are a normal part of how a human heart operates.
Palpitations That Deserve Ongoing Attention
There is a meaningful exception to the reassuring picture above: when premature ventricular beats are extremely frequent, occurring in more than about 15 to 20 percent of all heartbeats over a 24-hour period, they can gradually weaken the heart muscle over months or years, a condition sometimes called PVC-induced cardiomyopathy. This is rare, but it is why doctors sometimes recommend catheter ablation for people who have a very high PVC burden even in the absence of symptoms. The good news is that if the PVCs are successfully suppressed, the heart muscle tends to recover its strength.
Sustained arrhythmias, meaning abnormal rhythms that last more than a few seconds and involve rates above 100 beats per minute, also require closer follow-up. Supraventricular tachycardia, atrial flutter, and atrial fibrillation each have their own management pathways and long-term implications, but they share the common thread of being identifiable and treatable once properly diagnosed. Unlike the fleeting premature beats most people feel, these sustained rhythms usually produce symptoms that clearly interfere with daily life, which is what prompts evaluation in the first place.