Palpitations

Arrhythmias Overview of Abnormal Heart Rhythms Abnormal heart rhythms (arrhythmias) are sequences of heartbeats that are irregular, too fast, too slow, or conducted via an abnormal electrical pathway through the heart. Heart disorders are... read more range from harmless to life threatening.

The most common arrhythmias include

Both of these arrhythmias usually occur in people without a heart disorder and are harmless. The premature beat itself is not felt. What is felt is the following normal heartbeat, which occurs after a slight delay and is slightly stronger than usual. Although people feel as if their heart skipped a beat, it actually did not.

Other arrhythmias that cause palpitations and may be caused by serious heart disorders include

These other arrhythmias involve the heart beating much faster than normal. Arrhythmias in which the heart beats too slowly rarely cause palpitations, although some people do feel the slow rate.

Some arrhythmias (for example, atrial premature beats, ventricular premature beats, or PSVT) often occur in people who have no serious underlying disorders. Others are often caused by a serious heart disorder or a disorder elsewhere in the body.

Serious heart disorders include angina Angina Angina is temporary chest pain or a sensation of pressure that occurs while the heart muscle is not receiving enough oxygen. A person with angina usually has discomfort or pressure beneath the... read more , heart attack Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) Acute coronary syndromes result from a sudden blockage in a coronary artery. This blockage causes unstable angina or a heart attack (myocardial infarction), depending on the location and amount... read more (acute coronary syndrome), congenital heart diseases (for example, the Brugada syndrome or congenital long QT syndrome Torsades de Pointes Ventricular Tachycardia Torsades de pointes ventricular tachycardia is a specific type of ventricular tachycardia that occurs in people who have a particular disorder of the heart's electrical activity called a long... read more ), disorders of heart valves, and conduction system disturbances (for example, Wolff-Parkinson-White syndrome Wolff-Parkinson-White (WPW) Syndrome Wolff-Parkinson-White syndrome is a disorder in which an extra electrical connection between the atria and the ventricles is present at birth. People may have episodes of a very rapid heartbeat... read more ).

Disorders not related to the heart that may cause arrhythmias include

Arrhythmias that cause the heart to beat too fast can cause complications (particularly in older people). If the heart goes too fast, it may not be able to pump blood adequately, and people may feel faint or pass out or develop heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more . Heart failure occurs mainly in people who have previously had heart failure or a heart attack, although it can occur in other people if the heart rate is very fast or if the heart beats too fast for a long time. A rapid heart rate also increases the oxygen needs of the heart muscle. People who have narrowing of the arteries to the heart muscle (coronary artery disease Overview of Coronary Artery Disease (CAD) Coronary artery disease is a condition in which the blood supply to the heart muscle is partially or completely blocked. The heart muscle needs a constant supply of oxygen-rich blood. The coronary... read more ) can develop chest pain due to angina or a heart attack (which may be fatal).

Some arrhythmias, particularly ventricular tachycardia, are unstable and can lead directly to cardiac arrest.

In people with palpitations, certain symptoms and characteristics are cause for concern. They include

People who have palpitations and any warning signs should go to an emergency department right away, as should those who have continuous, ongoing palpitations. Those who have fainting, chest pain, or shortness of breath should call emergency services.

People without warning signs who have occasional palpitations or had an episode that stopped should call their doctor. The doctor will determine how quickly they need to be seen based on their age, underlying conditions, and other symptoms.

Doctors first ask questions about the person's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination helps determine the possible cause.

Doctors ask

Sometimes doctors ask the person to tap out the rate and cadence of palpitations because the pattern of beats can help them determine the cause.

The physical examination begins with the doctor checking the vital signs (pulse, temperature, and blood pressure). The pulse rate and whether the pulse is regular or irregular help suggest causes. An elevated temperature suggests fever is the cause. A low blood pressure does not suggest a cause but indicates extreme urgency.

Doctors listen to the heart for abnormal sounds that might indicate a valve disorder or heart inflammation. They listen to the lungs for sounds that indicate heart failure. They look at and feel the front of the neck to see if the thyroid gland is enlarged or inflamed.

Palpitations that occur with other symptoms, such as shortness of breath, chest pain, weakness, fatigue, or fainting, are more likely to result from an abnormal heart rhythm or a serious disorder.

Even though most causes of palpitations are not serious, testing typically is done.

ECG Electrocardiography Electrocardiography (ECG) is a quick, simple, painless procedure in which the heart’s electrical impulses are amplified and recorded. This record, the electrocardiogram (also known as an ECG)... read more is done. If the ECG is done while the person is having palpitations or an abnormal pulse rate, the diagnosis is usually clear. However, only a few of the possible causes produce an abnormal ECG when people are not having palpitations. Thus, people who have intermittent palpitations may need to wear an ECG monitor for a day or two (Holter monitoring—see figure ) or for a longer period (event recorder) to detect brief or irregularly occurring abnormal rhythms. In some people, doctors may insert a device underneath the skin to monitor the heart beat. This device is called a loop recorder, and it continuously monitors the person's heartbeat. Doctors can then use an external monitor to check the loop recorder for abnormal heart rhythms. Some commercially available products such as fitness trackers, which monitor heart rate, and other trackers that monitor track heart rhythms, are available for smart phones and watches but provide more limited information.

Laboratory testing is needed. Doctors do a complete blood count and measure serum electrolytes, including potassium, magnesium, and calcium. Doctors may measure other substances in the blood (cardiac markers) if the person has other symptoms that suggest a possible acute coronary syndrome Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) Acute coronary syndromes result from a sudden blockage in a coronary artery. This blockage causes unstable angina or a heart attack (myocardial infarction), depending on the location and amount... read more . Doctors measure levels of thyroid hormone in the blood if they suspect an overactive thyroid and measure levels of other hormones in people who may have pheochromocytoma Pheochromocytoma A pheochromocytoma is a tumor that usually originates from the adrenal glands’ chromaffin cells, causing overproduction of catecholamines, powerful hormones that induce high blood pressure and... read more . Other tests may be done, depending on what other causes doctors suspect.

Imaging is sometimes needed. In people with ECG findings that suggest heart disease, doctors do echocardiography Echocardiography and Other Ultrasound Procedures Ultrasonography uses high-frequency (ultrasound) waves bounced off internal structures to produce a moving image. It uses no x-rays. Ultrasonography of the heart (echocardiography) is one of... read more and sometimes magnetic resonance imaging Magnetic Resonance Imaging (MRI) of the Heart With magnetic resonance imaging (MRI), a powerful magnetic field and radio waves are used to produce detailed images of the heart and chest. This expensive and sophisticated procedure is used... read more (MRI) of the heart. People with symptoms during activity require stress testing Stress Testing Stressing the heart (by exercise or by use of stimulant drugs to make the heart beat faster and more forcibly) can help identify coronary artery disease. In coronary artery disease, blood flow... read more sometimes with stress echocardiography or nuclear scanning.

Electrophysiologic (EP) testing Electrophysiologic Testing Electrophysiologic testing is used to evaluate serious abnormalities in heart rhythm or electrical conduction (see Overview of Abnormal Heart Rhythms). In people in whom an arrhythmia is already... read more is done when people's symptoms are severe and doctors suspect a dangerous heart rhythm problem that was not found with other tests. In this test, doctors pass small electrodes through a vein into the heart. The electrodes record the heart's electrical activity in more detail than an ECG does.