Heart Palpitations: What They Mean and When to Worry

What palpitations feel like

People describe them in different ways, and the description is a useful clue:

Common harmless causes

Extra beats

Premature atrial or ventricular contractions are early beats followed by a brief pause and a stronger next beat. Almost everyone has some. They are more noticeable at rest, lying on your left side, or at night. See premature ventricular contractions.

Lifestyle triggers

• caffeine, energy drinks and pre-workout supplements
• alcohol, especially binge drinking ("holiday heart")
• nicotine and vaping
• recreational drugs such as cocaine, amphetamines and cannabis
• lack of sleep and dehydration
• large, heavy meals

Emotions and anxiety

Stress, anxiety and panic attacks release adrenaline, which speeds the heart and makes you more aware of it. Palpitations from anxiety are usually fast and regular.

Hormones

Pregnancy increases blood volume and heart rate. Menopause, periods and an overactive thyroid all commonly cause palpitations.

Medicines

Decongestants such as pseudoephedrine, asthma inhalers, thyroid medicine, some antidepressants, ADHD stimulants and some herbal products, including bitter orange and ephedra, can trigger palpitations.

Other medical causes

Fever, anemia, low blood sugar, low potassium or magnesium, and dehydration all raise the heart rate.

Heart rhythm causes

• Atrial fibrillation: irregular and often fast. More common after 60 and with high blood pressure. It raises stroke risk.
• Supraventricular tachycardia: sudden bursts of 150 to 250 beats per minute in otherwise healthy, often younger people. See paroxysmal supraventricular tachycardia.
• Atrial flutter.
• Ventricular tachycardia: a dangerous fast rhythm from the lower chambers, usually in people with heart disease. It can cause fainting or cardiac arrest.
• Wolff-Parkinson-White syndrome, long QT syndrome and other inherited conditions.
• Postural tachycardia syndrome (POTS): the heart rate jumps by 30 or more beats per minute on standing.

Heart palpitations: when to call 911

Call 911 or your local emergency number, or go to the nearest ER, if palpitations come with any of these:

• chest pain or pressure
• fainting, nearly fainting or severe dizziness
• severe shortness of breath
• confusion or trouble speaking
• a very fast heart rate at rest that does not settle
• palpitations brought on by exercise

These can signal a dangerous rhythm, a heart attack or a blood clot in the lungs.

What you can do during an episode

• Sit or lie down so you do not fall if you feel faint.
• Breathe slowly: in for 4 seconds, out for 6.
• Check your pulse at your wrist or neck for 30 seconds and double it. Note whether it is regular or irregular. A smartwatch ECG recording is useful to show your doctor.
• For known SVT, your doctor may have taught you vagal maneuvers, such as bearing down as if straining for 15 seconds, which can stop an episode.

How doctors find the cause

Your doctor will ask how the palpitations start and stop, how long they last, how fast they feel, what you were doing, and about caffeine, alcohol, drugs, medicines and family history. They will check your pulse, blood pressure and heart sounds.

Tests often include an ECG, blood tests for anemia, thyroid function and electrolytes, and a heart monitor worn for 24 hours to 2 weeks, or longer with a patch or implantable loop recorder if episodes are rare. An echocardiogram looks for structural heart disease. For full details, see heart palpitations as a condition.

Reducing palpitations

• Cut back on caffeine, alcohol and nicotine.
• Sleep 7 to 9 hours and stay hydrated.
• Exercise regularly, which lowers resting heart rate and anxiety.
• Use relaxation techniques, yoga or breathing exercises.
• Review medicines and supplements with a pharmacist.

Frequently asked questions

When should I call 911 for heart palpitations?

Call 911 or your local emergency number if palpitations come with chest pain, fainting or near fainting, severe breathlessness, confusion, or a very fast heartbeat at rest that will not settle. Palpitations during exercise also need urgent assessment.

Are heart palpitations dangerous?

Most are not. They are usually caused by harmless extra beats, stress, caffeine or hormones. They are more likely to be serious if you have heart disease, faint, have chest pain, or have a family history of sudden death at a young age.

Why do I get palpitations at night?

At night there are fewer distractions, so you notice your heartbeat more, especially lying on your left side. Alcohol, late caffeine, large meals, reflux, sleep apnea and anxiety can also trigger extra beats at night.

Can anxiety cause heart palpitations?

Yes. Anxiety and panic release adrenaline, which speeds and strengthens the heartbeat. These palpitations are usually fast and regular. Your doctor may still want an ECG to rule out a rhythm problem, especially if palpitations start suddenly or happen without stress.

What do skipped heartbeats mean?

A skipped beat is usually an early (premature) beat followed by a pause and a stronger beat. Occasional ones are normal. Very frequent extra beats, or extra beats with fainting or breathlessness, should be checked with an ECG and heart monitor.