What are palpitations?
Palpitations are unpleasant sensations of excessively strong, rapid and/or irregular heartbeats. In many people who experience palpitations, no heart disease or abnormal heart rhythms (arrhythmias) can be found and the cause of the palpitations is unknown.
In others, palpitations may be caused by arrhythmias of different types (heartbeats that are too slow, too rapid, irregular, or too early) or by other heart conditions such as leaking valves. Sometimes the underlying cause is unrelated to the heart — anaemia or an overactive thyroid gland, for instance, can cause palpitations. Palpitations can occur in everyone at some time during exercise, stress, pain or fright, but a normal heartbeat should return quickly.
What causes palpitations?
Palpitations can be triggered in some people by heavy smoking, excessive caffeine (from tea, coffee or cola drinks), food sensitivities or allergies, certain food colourings and preservatives, and some types of medications or reactions to medications. Fever may also cause an increased or abnormal heart rate while it is present.
Excessive levels of thyroid hormone or hormone rushes in pregnant women often cause a faster heart rate and may cause palpitations briefly. One condition sometimes seen in women is called paroxysmal atrial tachycardia (PAT), which causes the heart to beat rapidly (often twice the normal rate). It is associated with faulty electrical conduction between the chambers of the heart, and may last for a few seconds or several hours before returning to normal.
Palpitations may also be a symptom of several different types of arrhythmias, heart disease or heart attack. Sometimes the heart may have inappropriate beats (called ectopic beats or premature extrasystoles) which may give the sensation of palpitations but are not considered serious unless occurring frequently. Atrial fibrillation (AF), where the heart beats rapidly and irregularly, is another common cause of palpitations.
Certain medications that are used for asthma, angina pain, respiratory and lung conditions, and depression may have palpitations as a side effect. Excessive alcohol intake is known to cause palpitations in some people.
There are a number of other causes of palpitations but these are not as common. Inadequate supplies of oxygen in the blood, as seen in anaemia, can be a cause, so too can acid reflux (stomach acid rising back up the oesophagus). Palpitations can be one of the symptoms of a rare adrenal gland tumour called phaeochromocytoma.
What can your doctor do?
Your doctor may evaluate your palpitations through blood tests, electrocardiograms (ECGs), echocardiograms, a Holter monitor (a portable ECG machine that can monitor heartbeat for 24 hours), exercise stress tests, and a test of the coronary arteries. Rarely, electrophysiological studies are needed to determine the cause of an abnormal heart rhythm by applying small electric currents directly to the heart and recording its response.
Blood tests can also measure the levels of thyroid hormone, potassium, magnesium and medications that may be causing the palpitations. Your doctor may also check for food sensitivities and allergies.
Treatment of palpitations
Palpitations that are not related to specific arrhythmias or heart disease may not require specific treatment and your doctor may advise you to reduce emotional and physical stress. Your doctor may prescribe medications to regulate abnormal heartbeats.
What you can do
- Reduce physical stress and emotional stress where possible.
- Stop smoking.
- Reduce your intake of caffeine and alcohol.
- Beware of food sensitivities and avoid preservatives and food colourings where possible.
- Review your medications, including over-the-counter medications such as cold and flu preparations, eye drops and herbs and supplements, with your doctor or pharmacist.
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4. MedlinePlus Medical Encylopedia. A service of the US National Library of Medicine and the National Institutes of Health. Paroxysmal supraventricular tachycardia [updated 2008, May 12; accessed 2009, May 11]. Available at: http://www.nlm.nih.gov/medlineplus/ency/article/000183.htm
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