Heart palpitations are the feelings of having a fast-beating, fluttering or pounding heart. Stress, exercise, medication or, rarely, a medical condition can trigger them. Although heart palpitations can be worrisome, they're usually harmless. In rare cases, they can be a symptom of a more serious heart condition, such as an irregular heartbeat (arrhythmia), that might require treatment.

Symptoms

Heart palpitations can feel like your heart is:

Skipping beats

Fluttering rapidly

Beating too fast

Pounding

Flip-flopping

You might feel heart palpitations in your throat or neck, as well as your chest. They can occur when you're active or at rest.

When to see a doctor

Palpitations that are infrequent and last only a few seconds usually don't need to be evaluated. If you have a history of heart disease and have palpitations that occur frequently or worsen, the consult your doctor immediately.

Seek emergency medical attention if heart palpitations are accompanied by:

Chest discomfort or pain

Fainting

Severe shortness of breath

Severe dizziness

Occasionally heart palpitations can be a sign of a serious problem, such as an overactive thyroid gland (hyperthyroidism) or an abnormal heart rhythm (arrhythmia). Arrhythmias might cause a very fast heart rate (tachycardia), an unusually slow heart rate (bradycardia) or an irregular heart rhythm.

Complications

Unless a heart condition is causing your heart palpitations, there's little risk of complications. For palpitations caused by a heart condition, possible complications include:

Fainting: If your heart beats rapidly, your blood pressure can drop, causing you to faint. This might be more likely if you have a heart problem, such as congenital heart disease or certain valve problems.

Cardiac arrest: Rarely, palpitations can be caused by life-threatening arrhythmias and can cause your heart to stop beating effectively.

Stroke: If palpitations are due to a condition in which the upper chambers of the heart quiver instead of beating properly (atrial fibrillation), blood can pool and cause clots to form. If a clot breaks loose, it can block a brain artery, causing a stroke.

Heart failure: This can result if your heart is pumping ineffectively for a prolonged period due to an arrhythmia, such as atrial fibrillation. Sometimes, controlling the rate of an arrhythmia that's causing heart failure can improve your heart's function.

Diagnosis

If your doctor suspects your palpitations are caused by an arrhythmia or other heart condition, tests might include:

Electrocardiogram (ECG): In this noninvasive test, a technician places leads on your chest that record the electrical impulses that make your heart beat.
An ECG can help your doctor detect irregularities in your heart's rhythm and structure that could cause palpitations. The test will be performed either while you rest or during exercise (stress electrocardiogram).

Holter monitoring: You wear this portable device to record a continuous ECG, usually for 24 to 72 hours, while you keep a diary of when you feel palpitations. Holter monitoring is used to detect heart palpitations that aren't found during a regular ECG exam.

Event recording: If you don't have irregular heart rhythms while you wear a Holter monitor or if the events occur less than once weekly, your doctor might recommend an event recorder.

Echocardiogram: This noninvasive exam, which includes an ultrasound of your chest, shows detailed images of your heart's structure and function.Ultrasound waves are transmitted, and their echoes are recorded with a device called a transducer that's held outside your body. A computer uses the information from the transducer to create moving images on a video monitor.