Medically reviewed by Nachiket J. Patel, MD, FACC, FSCAI. Last reviewed July 2026.
Palpitations are the sensation that your heart is racing, pounding, fluttering, pausing, or skipping a beat. Many are not dangerous, but the safest way to understand recurrent symptoms is to record the heart rhythm while they are happening and interpret that rhythm in the context of your symptoms and heart health.
Palpitations describe what you feel; they do not tell us the cause. You may notice a hard thump after a pause, a rapid regular heartbeat that starts and stops suddenly, or an irregular flutter.
The cause may be an early beat from the upper or lower chambers. It may also be atrial fibrillation, atrial flutter, supraventricular tachycardia, a slow rhythm, or—less commonly—a more dangerous rhythm. Sometimes the rhythm is normal but fast because of fever, dehydration, anemia, pain, stress, or thyroid disease.
That is why I try not to label palpitations from the sensation alone. The most useful question is: What was the heart rhythm at the exact time you felt the symptom?
What can trigger palpitations?
Contributors include poor sleep, stress, illness, dehydration, alcohol, nicotine, stimulants, decongestants, supplements, hormonal changes, anemia, thyroid problems, and electrolyte abnormalities. Caffeine affects people differently; note the amount and timing rather than assuming it is the cause. In other patients, palpitations reflect an electrical or structural heart problem.
A trigger does not prove that a symptom is harmless. Palpitations during exercise, symptoms in someone with cardiomyopathy or known valve disease, or a family history of unexplained sudden death deserve timely evaluation.
When to call 911
Call 911 for palpitations accompanied by:
- Chest pain or pressure
- Severe or rapidly worsening shortness of breath
- Fainting, collapse, or difficulty waking
- New facial droop, arm weakness, speech difficulty, confusion, or another possible stroke symptom
- A sustained very fast or very slow pulse with severe weakness, sweating, or a feeling that you may pass out
Do not drive yourself when you may be having a heart or neurologic emergency. Even if the rhythm settles, describe what happened and how long it lasted.
Palpitations without these emergency features still warrant prompt contact with a clinician when they are new, prolonged, increasing, brought on by exercise, or associated with near-fainting.
What the evaluation is like
The first visit begins with the story: whether the heartbeat felt regular or irregular, fast or slow, began suddenly, and came with chest discomfort, shortness of breath, dizziness, or fainting.
An electrocardiogram, or ECG, may identify an ongoing arrhythmia or electrical clue. A normal office ECG cannot exclude a rhythm that comes and goes.
Selected patients may need blood testing, an echocardiogram, or an exercise test when symptoms occur with exertion. Not every patient needs every test.
Choosing the right heart monitor
Ambulatory monitoring is most useful when the type and duration of the monitor match how often symptoms happen. A 24- or 48-hour Holter monitor may work well for daily symptoms. A patch, mobile telemetry monitor, or event monitor may be more useful when episodes occur less often. Rare but concerning events sometimes require much longer monitoring, including an implanted loop recorder.[1]
The goal is to match the rhythm with the symptom. Palpitations may occur during an arrhythmia, isolated premature beats, or a normal rhythm. Each result leads to a different conversation.
Consumer watches can provide clues when they capture a tracing during symptoms. Save the tracing or PDF—not only the automated label or heart-rate number. Devices can misclassify rhythms, so the result still needs clinical review.[2]
What you can do now
If you are stable and the episode is not an emergency, keep a short record that includes:
- The exact start and stop time
- What you were doing just before it began
- Whether the pulse felt regular or irregular
- The heart rate, if you can check it safely
- Chest discomfort, shortness of breath, dizziness, or near-fainting
- Possible contributors such as poor sleep, illness, dehydration, alcohol, caffeine, or a new medication
Bring a complete list of prescriptions, over-the-counter products, energy products, and supplements. If a watch or home device recorded the event, bring the tracing. Do not stop a heart medication or take an extra dose based only on a home reading unless your clinician has given you specific instructions.
How treatment is chosen
Treatment depends on the rhythm, symptom burden, and underlying heart health. The plan may include reassurance, correcting a reversible contributor, medication, cardioversion, catheter ablation, or—for selected slow-rhythm problems—a pacemaker. These treatments address different problems.[3][4][5]
Atrial fibrillation requires a separate assessment of stroke risk. Feeling well—or having only brief symptoms—does not by itself answer whether stroke-prevention medication is appropriate.[3]
Frequently asked questions
Does a skipped beat mean I have atrial fibrillation?
No. Premature beats commonly feel like a pause followed by a stronger thump. Atrial fibrillation is typically irregular, but the sensation alone cannot reliably distinguish the two. An ECG tracing during symptoms is far more useful.
What if the monitor shows a normal rhythm while I feel palpitations?
That is still useful information. It may show that the symptom is not being caused by a dangerous arrhythmia, although the complete result and symptom pattern still need interpretation.
Can dehydration cause palpitations?
Yes. Dehydration can increase the heart rate and may make premature beats more noticeable. It can also change blood pressure, kidney function, and electrolytes. Ask for individualized fluid guidance if you have heart failure, kidney disease, or a prescribed fluid limit.
Can anxiety cause palpitations?
Stress and anxiety can increase adrenaline and make the heartbeat faster or more noticeable. That does not mean every palpitation should be dismissed as anxiety. Recurrent or concerning symptoms deserve a rhythm-based evaluation.
Is an irregular-heart-rhythm alert from my watch a diagnosis?
No. Save it for review, but do not treat it as a final diagnosis. Call sooner if it occurs with chest pressure, shortness of breath, fainting, or neurologic symptoms.
Dr. Patel’s Bottom Line
What I want patients to remember is this: palpitations are common, but guessing from the feeling is unreliable. Capture the rhythm, record the circumstances, and pay attention to associated symptoms. If the episode includes chest pressure, severe shortness of breath, fainting, or possible stroke symptoms, call 911. Otherwise, a careful history and the right monitor will usually move us much closer to the answer.
Sources and Further Reading
- 2017 ISHNE-HRS Expert Consensus Statement on Ambulatory ECG and External Cardiac Monitoring/Telemetry, Heart Rhythm, 2017.
- 2021 ISHNE/HRS/EHRA/APHRS Collaborative Statement on Mobile Health in Arrhythmia Management, Heart Rhythm, 2021.
- 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation, Circulation, 2024.
- 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia: Executive Summary, Circulation, 2016.
- 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay, Circulation, 2019.
Related heart and vascular information
Schedule an appointment
If you have recurrent palpitations, a racing or irregular pulse, or symptoms that have not been explained, request an appointment with Flow Heart & Vascular in Mesa, Arizona. Call 911 for emergency symptoms.
This page provides general education and does not replace individualized medical advice. Do not start, stop, or change a medication based only on this website.
