Introduction

Palpitation is the sensation of rapid, irregular, or forceful heartbeats or an awareness of one's own heartbeat.^[1] It does not necessarily imply pathology. It is not usually constant but occurs intermittently. Sometimes it is awareness of an intermittent thump in the chest when one heartbeat is rather more forceful than the rest.

There may be cardiac disease but often the problem is anxiety and undue circumspection.

Causes^[1]

• Various types of tachycardia - heart rate more than 100 beats per minute (BPM)
• Atrial fibrillation (AF) - rate is fast or slow
• Extrasystoles (ventricular or atrial)
• Bradycardia - heart rate less than 60 BPM - may cause an increased awareness of the heartbeat but is predominantly associated with syncope and presyncope

For more information, see separate dedicated articles: ECG Identification of Arrhythmias, Anti-arrhythmic Drugs, Defibrillation and Cardioversion, Atrial Fibrillation, Narrow Complex Tachycardia, Paroxysmal Supraventricular Tachycardias, Junctional Tachycardias, Ventricular Fibrillation, Atrial Flutter, Extrasystoles, and ECG Identification of Conduction Disorders.

Epidemiology

Palpitations may be the reason for 30 to 40% or referrals to cardiology clinics but, in most cases, there is no significant organic pathology. However, in a few there is serious and potentially fatal disease.

The elderly are more likely to be aware of their heartbeat but they are also more likely to have cardiac disease. A study from Hong Kong found that in the elderly both palpitations and abnormal rhythms were quite common in the elderly but bore little relationship to each other.^[2]

In athletes, the incidence of palpitations varies from 0.3% to 70%, depending on age and type of sport. Older athletes undertaking endurance sports have the highest incidence. Atrial fibrillation (AF) can account for up to 9% of rhythm disturbances in elite athletes and up to 40% in those with long-standing symptoms.^[3]

History

• Check what the patient means by palpitations. It should mean an awareness of the heart beating. It may really be a pulsatile tinnitus or a carotid bruit.
• Ask the patient how often it happens, how long it lasts and if there are any precipitating or relieving factors. Sometimes people are only aware of it whilst lying down at night.
• Is the rate regular or irregular?
• Ask the patient to tap out the beat. This may be regular or irregular. It may be a normal rate or fast. Try to estimate the rate.
• Are there any symptoms that accompany the palpitations, such as sweating or breathlessness? These may be organic or psychosomatic in origin.
• Is there any associated chest pain? If there is, it is of marked sinister significance.
• Enquire about consumption of caffeine. Palpitations may be related in time to consumption but assess daily intake too. Tea contains rather less caffeine than instant coffee whilst percolated coffee contains much more. Other drinks such as cola contain caffeine, and a brand of drink called Red Bull® contains so much caffeine that if it is taken by a sportsman who is then drug tested, he may well have a level of caffeine that is over the permitted limit.
• Ask about alcohol consumption.
• Ask about smoking. The level of nicotine in cigars tends to be rather higher than in cigarettes.
• In young people ask about use of illicit substances, especially cocaine, ecstasy - methylenedioxymethamfetamine (MDMA) - and amfetamines. High levels of anxiety can also result from withdrawal of sedatives such as benzodiazepines.
• If the problem is palpitations in a young sportsman during training, it is imperative to get an accurate diagnosis before high-intensity training is resumed.^[4] The assumption has been made that palpitations occurring at rest in athletes are benign but this theory has yet to be validated.^[3]
• Ask about general health and wellbeing. There may be great anxiety in the life at present. There may be shortness of breath on exertion, loss of weight or gain in weight, with ankle oedema.
• Does the patient have palpitations at present?

Examination

If the patient currently has the palpitations then it is easy to assess the rate and regularity of the pulse and to get an ECG to confirm the diagnosis but this is unusual. Nevertheless, it may be possible to gain information even if the patient is between attacks.

• Does the patient look well? Does the patient look anxious? Is there exophthalmos to suggest thyrotoxicosis? Are the fingers stained with nicotine? Do the hands feel warm or cold?
• Ask the patient to hold their arms outstretched in front of them with the palms down and to spread their fingers. A fine tremor may suggest thyrotoxicosis or anxiety. Sometimes placing a sheet of paper on the dorsum of the hand accentuates the tremor.
• Examination of the pulse can give a great deal of information. Firstly, assess the quality of the pulse. Is it full and bounding, rather weak or normal? Then, assess the quality of the artery. Is it soft and elastic or rather rigid? The brachial artery may be a better place to assess this. Is the rate regular? If irregular, it may be regularly irregular with irregularities at a constant interval or irregularly irregular with a chaotic rhythm. The former suggests ectopic beats. The latter suggests AF or flutter.
• Count the rate over an adequate interval. This will need to be longer if the rate is irregular or slow.
• Check the blood pressure
• Examine the heart, noting the position and character of the apex beat, any parasternal heave or thrills, the normality of the heart sounds and if there are any additional sounds.

Differential diagnosis

• The patient may simply be anxious but this is really a diagnosis of exclusion. Palpitations in patients who somatise more and have more health-related anxiety and more psychiatric distress are significantly less likely to be related to demonstrable cardiac arrhythmias.^[5] People who have had a cardiac transplant are more aware of their heartbeat, perhaps because they are naturally more anxious about their heart.
• It may be part of a panic attack.
• There may be an occasional "missed beat". This is really a misnomer, as what happens is a premature beat, usually from an ectopic source and this leads to a weak beat followed by a prolonged refractory period during which the ventricles fill more than usual and, when ejection occurs, it is more forceful than usual and so is noticed. Occasional ectopics are fairly common and usually of no sinister significance. They are more likely with a slow pulse.
• AF or flutter is often paroxysmal before AF becomes established. It is often quite fast but can be slow.The crucial feature is the random irregularity but this is more difficult to discern with a faster rate. AF is often associated with shortness of breath on exertion, as it tends to reduce cardiac output by about 20%.
• As a general rule, ventricular tachycardia (VT) has a rate of 120 to 160 BPM and supraventricular tachycardia (SVT) is 160 to 200 BPM.
• Paroxysmal tachycardia can result from a junctional re-entry phenomenon. This tends to produce a very fast rate, often in a young person. Wolff-Parkinson-White (WPW) syndrome is well documented. Lown-Ganong-Levine (LGL) syndrome has diagnostic criteria but there is dispute about whether it is really a separate disease entity.
• A hyperdynamic pulse may occur with anaemia and thyrotoxicosis. The latter may produce AF, especially in the elderly where that may be the only feature. The classical signs of thyrotoxicosis are often few or absent and the elderly may have "apathetic thyrotoxicosis." Drugs that reduce the resistance in the circulation may also be responsible. These can include nitrates and calcium channel blockers. Excessive use of a beta agonist inhaler will cause palpitations.
• Irregularities of rhythm may occur with cardiomyopathy.
• Bradycardia may produce palpitations, as a high stroke volume is required to meet the necessary cardiac output.
• Pheochromocytoma is a rare cause of paroxysmal palpitations. It tends to occur with multiple endocrine neoplasia syndromes - usually MEN2 - and usually runs in families.
• An insulinoma is also generally part of an MEN syndrome but usually MEN1 and, both this and the treatment of diabetes, may lead to hypoglycaemia that can cause an outpouring of catecholamines and palpitations.

Investigations

Primary care clinicians are unlikely to be able to make an accurate assessment of patients presenting with palpitations on the basis of history and examination alone. Further investigation is invariably needed.^[6]

• In the days before the ready availability of ECG machines, a technique used to differentiate between ectopic beats and AF was to exercise the patient. The faster heart rate would "pace out" the ectopics to give a more regular rate but in AF the rhythm would often become more irregular. This is largely of historical interest.
• The gold standard is a full 12 leads ECG taken at the time of palpitations. It should, however, be performed even if the palpitations have resolved. It may show an irregular rate and it is easy to deduce the type. There may be abnormalities suggestive of ischaemia, hypertrophy or cardiomyopathy. There may be occasional ectopics that are not currently causing symptoms. There may be incomplete heart block. There is a short PR interval in WPW syndrome and LGL syndrome and a delta wave in the former.
• Basic blood tests should include a full blood count, urea and electrolytes and thyroid function tests.
• A 24-hour ECG should be arranged (many GPs now have direct access to this). The patient is given a device to wear for 24 hours (a Holter monitor) which is returned to the hospital for analysis the following day. The time that palpitations start and finish should be noted so this can be correlated with the ECG recording.^[7] As a refinement, an event recorder can be used for patients whose palpitation frequency is less than daily.^[8] For added convenience, leadless monitors have been developed.^[9]
• If the problem is related to exercise then a treadmill ECG is required. Sometimes there is an irregularity at rest that is suppressed on exercise. These tend to be of rather less sinister significance than an irregularity that arises on exercise.
• Particularly if cardiomyopathy is suspected or if there are abnormal heart sounds, an echocardiogram may be indicated.

Management^[1]

Patients suffering from palpitations at the time of the consultation should be assessed to exclude any life-threatening arrythmia or any complications arising therefrom that might cause acute medical problems.

For patients who do not have palpitations at the time of the consultation but have a history of them, management is dependent upon the cause and is discussed in the articles about the various causes (see above under Causes for links).

Specialist referral^[1]

Following initial assessment, this should be considered for all people with:

• Symptoms suggestive of VT or SVT.
• Symptoms indicating serious complications of an arrhythmia.
• Risk factors for a serious arrhythmia:
• A family history of sudden cardiac death before 40 years of age.
• Evidence of major structural heart disease.
• A major ECG abnormality.

Following ambulatory monitoring, refer people with proven:

• VT
• SVT
• Atrial flutter
• Tachy-brady syndrome

Urgency of referral:

• All people with suspected or proven VT
• Clinical judgement should be used for other patients, based on:
  • The frequency of symptoms and their duration
  • A history of palpitations, accompanied by symptoms indicative of serious complications such as syncope, chest pain, or breathlessness

If no cause is found and it is felt that the patient is being simply too anxious or introspective, perhaps with a degree of cardiac neurosis then the first line is simply reassurance. If there is hypochondriasis due to depression, it should be treated. Otherwise, if treatment is needed, cognitive behavioural therapy (CBT) may be useful. Benzodiazepines are unlikely to produce a satisfactory long-term result, as they should not be used for more than 2 to 4 weeks; however, but SSRIs are safer and of proven effectiveness in panic attacks.^[10]

Patients who may not require referral

The threshold for referral will depend on individual clinical circumstances and the expertise of the individual clinician. The guidelines produced by Clinical Knowledge Summaries suggest the following may not need referral:

• Patients with characteristic symptoms of extrasystoles (missed beats followed by a strong beat, most noticeable at rest) if there is no evidence of IHD, major structural heart disease, or any major ECG abnormalities.
• Patients with sinus tachycardia may not need referral providing systematic examination is undertaken and appropriate investigations are arranged to exclude underlying causes (eg anaemia, heart failure, medication, chronic lung disease, thyrotoxicosis).

Prognosis

It is important to diagnose the serious causes of palpitations but, where no serious disease is found, the prognosis is not much different from matched controls as shown in several studies. In one from New York, there was cardiac disease is just under half of patients, a psychiatric diagnosis in about a third and no diagnosis in a sixth.^[11]