What are palpitations?

Palpitations are the sensation of a rapidly or irregularly beating heart.

How do they occur?

Palpitations can occur normally when your heart is working hard. For example, you might feel a rapid or irregular heartbeat when you have just exercised, have a fever, or are feeling anxious. At these times your heart may pump faster or increase the amount of blood it pumps with each beat. This is a normal response to lifting weights, walking up a hill, or becoming emotionally excited. Often you may not even notice this increased heart activity.

Medical conditions that can also cause palpitations include:

• anemia

• anxiety

• some thyroid problems

• hypoglycemia (low blood sugar)

• mitral valve prolapse, a mild deformity of one of the valves in your heart.

A very common cause of palpitations is the overuse of stimulants, including caffeine (coffee, tea, sodas), nicotine, diet pills, and medications such as decongestants. Accidental overdose of some medicines can cause palpitations. Examples of such medicines are theophylline, antidepressants, and thyroid hormone replacement.

Another less common cause of palpitations is a type of abnormal heartbeats called premature beats, PVCs (premature ventricular contractions), or ectopic beats. These are abnormal beats that are not a problem if they occur just once in a while. However, if they occur frequently or in sequence, they can lead to problems.

What are the symptoms?

Palpitations may feel like your heart is:

• jumping around your chest

• skipping a beat

• fluttering

• pounding

• racing.

Occasionally, you may feel lightheaded or short of breath when you have palpitations. Usually, however, palpitations occur without other symptoms. Generally they last for a few seconds to a few minutes.

How is it diagnosed?

Your medical history is important. Your health care provider will want to know:

• when your palpitations occur

• whether any other symptoms are present

• how long you have been having the palpitations

• how long the palpitations last

• if your symptoms get better or worse with certain activities

• if you have been using any stimulants or medications.

Your health care provider will do a physical exam to check for possible cardiac and thyroid gland causes of palpitations.

An electrocardiogram (ECG) helps rule out serious heart rhythm disturbances. This test measures the electrical activity of your heart. You may need to wear a Holter monitor (a portable ECG) for 24 to 72 hours. This gives your provider a chance to see the ECG pattern when you have symptoms. However, sometimes symptoms do not occur when you are wearing the monitor.

Sometimes an echocardiogram is done. An echocardiogram uses sound waves to show images of your heart on a computer. It is a way to check for structural problems that might be causing palpitations.

Your health care provider may test a sample of your blood for anemia and thyroid problems. Testing your blood sugar level may also be done. However, a test of your blood sugar level may be helpful only if the blood is drawn at the time you are having palpitations.

How is it treated?

Palpitations are treated by treating the underlying cause. Stimulant use and anxiety are the two most common causes of palpitations and can be hard to treat. It can be difficult for people to give up stimulants such as caffeine and nicotine. It is also sometimes hard to identify the source of anxiety. A combined approach of counselling and medication can be used to treat anxiety.

Diet is another possible cause. Your health care provider may suggest that you change your diet and see if the palpitations go away.

If your palpitations persist and are frequent, or if they are producing significant symptoms, your health care provider may show you several physical maneuvers that may be used to slow your pulse without medication.

Your health care provider may prescribe medicine to take either at the time the palpitations occur or every day to prevent palpitations. It usually takes only a few hours for the medicine to start working. It may be possible to stop taking the medicine after a few months.

How can palpitations be prevented?

The best way to prevent palpitations is to avoid overuse of stimulants, such as cigarettes or caffeine-containing coffee, tea, or soda.