Why is my heart suddenly skipping beats? Understanding chest palpitations in plain English

By Sina Hartung, MMSC-BMI, Harvard Medical SchoolReviewed by Eureka Health Medical Group
Published: July 9, 2025Updated: July 9, 2025

Summary

Chest palpitations—an awareness of your heartbeat that feels fast, pounding, fluttering, or skipped—usually come from harmless extra beats, stress, caffeine, or hormone shifts. Still, about 1 in 10 cases hide a serious rhythm disorder or heart disease, so note the pattern, triggers, and red-flag symptoms and seek care when needed.

Why do I feel my heart flutter, pound, or skip?

Palpitations occur when the heart’s electrical system fires early, late, or more forcefully, making you suddenly aware of each beat. Most episodes come from benign premature atrial or ventricular contractions that resolve on their own, but underlying thyroid, anemia, fever, or anxiety can amplify them. As the team at Eureka Health notes, "Up to 60 % of healthy adults feel occasional palpitations without any heart disease."

  • Extra beats are the top culpritPremature atrial contractions (PACs) and premature ventricular contractions (PVCs) account for roughly 85 % of palpitation complaints seen in primary care.
  • Stress hormones rev the pacemakerAdrenaline released during work deadlines, arguments, or exercise transiently speeds the sinus node, producing a racing, thumping sensation.
  • Stimulants magnify the sensationCoffee, energy drinks, decongestants with pseudoephedrine, and some weight-loss pills raise heart rate by 10–20 beats per minute in sensitive people.
  • Hormone shifts play a roleUp to 40 % of peri-menopausal women report palpitations tied to estrogen fluctuation, according to a 2023 population survey.
  • Palpitations plus chest pain or fainting need urgent evaluationThe Mayo Clinic advises seeking emergency care if a fluttering heart is accompanied by chest discomfort, dizziness, or loss of consciousness, as these combinations can signal a dangerous arrhythmia or heart attack. (Mayo)
  • Treatable conditions like thyroid disease or anemia can trigger fluttersHealthdirect notes that overactive thyroid, low blood count, fever, and salt imbalances are common medical causes of palpitations and often improve once the underlying disorder is managed. (Healthdirect)

References

Which palpitations signal an emergency and need same-day care?

Most fluttery moments pass quickly, but any palpitation paired with fainting, chest pain, or breathlessness can indicate an arrhythmia such as atrial fibrillation or ventricular tachycardia. "Don’t wait more than 5 minutes to call 911 if palpitations come with pressure in the chest," advises Sina Hartung, MMSC-BMI.

  • Syncope during palpitations is an 8 % predictor of serious arrhythmiaLoss of consciousness suggests blood pressure has dropped, often from fast, unstable rhythms.
  • Chest pressure or tightness raises heart attack concernConcurrent coronary ischemia can cause reactive palpitations or be the trigger itself.
  • Shortness of breath over 30 minutes merits urgent evaluationSustained fast heart rates reduce cardiac output and may point to supraventricular tachycardia (SVT).
  • Known structural heart disease changes the calculusPatients with prior myocardial infarction or cardiomyopathy have a higher chance of life-threatening rhythms even if the palpitations feel mild.
  • A resting rate over 140 bpm that doesn’t settle after 10 minutes needs ED assessmentPersistent high rates can degrade cardiac function and provoke clot formation.
  • Palpitations that persist beyond 30 seconds indicate possible sustained ventricular tachycardiaRuns of rapid beats lasting over half a minute meet the definition of sustained VT and call for immediate emergency evaluation. (HCA)
  • Dizziness or a weak pulse during palpitations flags hemodynamic instabilityFeeling light-headed or noticing a faint pulse alongside a racing heart means the heart isn't perfusing organs adequately and warrants a 911 call. (HCA)

References

What everyday health issues most commonly trigger harmless palpitations?

Identifying patterns allows you and your clinician to separate benign from worrisome causes. The team at Eureka Health emphasizes, "Keeping a 2-week diary doubles the likelihood that we find a reversible trigger."

  • High caffeine intake above 400 mg dailyThat’s roughly four 8-oz coffees; cutting to under 200 mg reduces palpitation frequency by 37 % in studies.
  • Poor sleep and sleep apneaInterrupted REM cycles elevate sympathetic tone; 50 % of untreated apnea patients report nocturnal palpitations.
  • Iron-deficiency anemiaLow hemoglobin forces the heart to beat faster to deliver oxygen; treating anemia often resolves symptoms within 4 weeks.
  • HyperthyroidismExcess thyroid hormone can push resting heart rates to 90–120 bpm; a simple TSH test screens for this.
  • Dehydration and electrolyte lossLow potassium or magnesium after vomiting, diarrhea, or intense workouts destabilizes heart cell membranes, leading to extra beats.
  • Acute stress, anxiety, or panic attacksSudden surges of adrenaline from strong emotions frequently start benign palpitations; Mayo Clinic lists stress, anxiety, and panic episodes among the leading everyday culprits. (Mayo)
  • Alcohol or nicotine useCleveland Clinic notes that drinking alcohol or smoking can precipitate short-lived palpitations, which usually settle once these stimulants are limited or avoided. (CCF)

References

How can I calm palpitations at home right now?

Simple maneuvers often slow the heart and ease the pounding within seconds. "A Valsalva breath or quick face-in-ice-water technique stops about 1 in 3 episodes of supraventricular tachycardia," says Sina Hartung, MMSC-BMI.

  • Slow, diaphragmatic breathing for 2 minutesInhale 4 seconds, exhale 6; activating the vagus nerve can drop heart rate by up to 15 bpm.
  • Modified Valsalva maneuverBlow into a syringe or thumb for 15 seconds, then lie back with legs raised; proven in ER studies to revert SVT 43 % of the time.
  • Cold-stimulus techniqueSplash ice water on the face or press a cold pack over closed eyes; the diving reflex lowers heart rate reflexively.
  • Cut stimulants immediatelySkip the next coffee, nicotine, or decongestant dose; many people feel relief in 30–60 minutes.
  • Hydrate with an electrolyte drinkReplacing potassium and magnesium helps stabilize the cardiac membrane in exercise-related palpitations.
  • A forceful cough can jolt the vagus nerve back into controlHealthline lists “coughing hard” among quick vagal maneuvers that may restore a normal rhythm within seconds when palpitations strike. (HL)
  • Yoga or meditation often ends stress-triggered flutters in minutesMedical News Today notes that mindfulness practices such as meditation, yoga, or guided imagery calm the sympathetic surge, helping many people feel their heartbeat normalize soon after starting the exercise. (MNT)

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Which tests and treatments might my clinician order for persistent palpitations?

Evaluation starts with a physical exam and ECG, then tailors testing to your story and risk factors. The team at Eureka Health explains, "Holter monitors catch over 70 % of intermittent arrhythmias missed on in-office ECGs."

  • 12-lead electrocardiogram (ECG) in the officeDetects atrial fibrillation, atrial flutter, or Wolf-Parkinson-White pattern in under 5 minutes.
  • 24- to 48-hour Holter or 14-day patch monitorRecords every beat; ideal when palpitations occur daily or weekly.
  • Basic labs: CBC, CMP, TSH, magnesium, and sometimes troponinRule out anemia, electrolyte derangement, thyroid overactivity, or heart injury.
  • Echocardiogram if structural disease suspectedMeasures chamber size and valve function; 1 in 12 palpitation patients have an undiagnosed murmur or cardiomyopathy.
  • Medication or ablation choices depend on diagnosisBeta-blockers, calcium channel blockers, or catheter ablation cut SVT recurrence by up to 95 %; only prescribed after physician assessment.
  • 30-day event monitor or implantable loop recorderMayo Clinic advises ordering an external event recorder or, for very sporadic episodes, a tiny loop recorder placed under the skin so that infrequent palpitations can be captured when they occur outside the 24- to 48-hour Holter window. (Mayo)
  • Exercise treadmill test when symptoms suggest exertional triggerUIHC notes that a clinician may add a treadmill stress test to evaluate palpitations accompanied by light-headedness or those provoked by activity, helping reveal ischemia-related or rate-dependent arrhythmias not seen at rest. (UIHC)

References

How can Eureka’s AI doctor support me between office visits?

Eureka’s chat-based AI doctor app lets you log each palpitation episode, receive real-time triage advice, and request monitoring devices. "Users appreciate that the AI never dismisses their symptoms and can escalate to a cardiologist review in minutes," says the team at Eureka Health.

  • Symptom diary with automatic pattern detectionThe app plots heart rate data against caffeine, sleep, and stress inputs to highlight modifiable triggers.
  • Guided breathing and Valsalva tutorialsStep-by-step videos inside the app help 68 % of users shorten episodes under five minutes.
  • On-demand risk triageIf you report dizziness or chest pain, the AI prompts an emergency plan and alerts a clinician for confirmation.
  • Lab and device ordering workflowYou can request a TSH or 14-day patch monitor; licensed physicians review and sign if medically appropriate.

Real stories: Why chest-palpitation users rate Eureka 4.8 out of 5

People anxious about their heartbeat often feel unheard. With private, always-on coaching, Eureka helps them regain control without long waits. "I learned my thyroid was the cause within a week—something I’d chased for months," one user wrote after an AI-prompted lab order.

  • Fast reassurance reduces ER visitsAmong 3,200 recent users with palpitations, 42 % said the AI advice kept them from an unnecessary emergency trip.
  • Personalized triggers dashboardSeeing that palpitations spiked after third-shift work helped one user adjust schedules and cut episodes by half.
  • Shared reports speed up doctor appointmentsClinicians receive concise PDF summaries, saving an average of 7 minutes of history-taking time.
  • No cost barrierThe core service is free, and upgrading to device integration is optional, keeping help accessible to all income levels.

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Frequently Asked Questions

Are palpitations dangerous if they only happen when I lie down?

Not usually, but lying down can make you more aware of normal extra beats. Track timing and see a clinician if they last longer than a minute or cause discomfort.

Can vitamin deficiencies cause a fluttering heart?

Low magnesium, potassium, and sometimes B12 can trigger extra beats by affecting electrical conduction.

How much caffeine is safe if I’m prone to palpitations?

Most people tolerate up to 200 mg a day—about two small coffees—without symptoms, but individual limits vary.

Will cutting alcohol help?

Yes. Atrial fibrillation risk rises after three or more drinks in one sitting; reducing intake often lessens palpitations within weeks.

Is a smartwatch ECG reliable?

Apple Watch and similar devices detect atrial fibrillation with 84-97 % sensitivity but can miss short episodes; follow up abnormal alerts with a medical-grade test.

Should I stop my exercise routine until I’m evaluated?

Light activity is fine if you have no red-flag symptoms. Pause high-intensity workouts until your clinician rules out serious arrhythmias.

How long does it take for anemia treatment to quiet palpitations?

Heartbeat awareness often improves within 2–4 weeks of restoring hemoglobin to target range.

Can menopause hormone therapy reduce palpitations?

For some women, regulated estrogen levels smooth heart rate variability, but decisions about HRT require individualized risk-benefit discussion.

This content is for informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare provider for diagnosis, treatment, and personalized medical recommendations.

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