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Palpitations and arrhythmia
MRC Research Fellow and General Practioner University of Southampton, UK
E-mail: caes{at}soton.ac.uk
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Abstract |
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 TOP Abstract What the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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Palpitations are the sensation of rapid, irregular or forceful heart beats. They are common and may indicate an arrhythmia. Abnormal heart rhythms may present with palpitations, chest pain, syncope or even sudden death, but are often silent, only detected when a doctor or nurse notices an abnormal rhythm when examining the patient for another reason. The aim of this article is to provide a strategy for the GP in training to assess whether palpitations signify an arrhythmia or not, and describe the features and management of the more common arrhythmia seen in general practice.
Primary care management GPs in training must be able to manage primary contact with patients who have a cardiovascular problem and co-ordinate care with other primary care health professionals, cardiologists and other appropriate specialists (including making timely and appropriate referrals), leading to effective and appropriate acute and chronic disease management. In addition they should be able to promote cardiovascular well-being by applying health promotion and disease prevention strategies appropriately, and describe strategies for early detection of cardiovascular problems that may already be present but have not yet produced symptoms.
The knowledge base
Person-centred care
Specific problem-solving skills and scientific aspects
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Assessment of palpitations |
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TOPAbstractWhat the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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History and examination can exclude significant problems in most patients. Ask about the duration, frequency, pattern and rhythm of the palpitations. Ask the patient to tap out the rhythm if the arrhythmia is not present at the time the patient is seen. Enquire about precipitating or relieving factors and associated symptoms such as chest pain, collapse or funny turns, sweating, breathlessness or hyperventilation.
Past history may also give a clue about whether palpitations indicate arrhythmia. Has the patient had previous episodes? Does the patient have a history of heart disease or thyroid disease? Is there a family history of syncope, arrhythmia or sudden death? Some drugs – prescription, over-the-counter, herbal or illicit – can cause arrhythmia, so take a full drug history. Ask about lifestyle factors. Excess caffeine can cause palpitation, as can alcohol. Smokers have a higher risk of coronary artery disease that may, in turn, cause arrhythmia. Finally ask about occupation. Arrhythmias may prevent a patient driving or directly prevent a patient carrying on certain occupations, such as pilot or train driver.
When examining a patient with palpitations, perform a general examination checking specifically for anaemia, anxiety, signs of thyrotoxicosis or other systemic disease. Perform a full cardiovascular examination checking blood pressure, pulse rate and rhythm, jugular venous pressure, heart size, heart sounds and murmurs and for evidence of left ventricular failure.
A resting 12-lead electrocardiogram (ECG) is all that is needed to investigate most patients with palpitations. If the ECG is abnormal or there are any other concerning factors, consider referral for an ambulatory ECG (if suspected asymptomatic arrhythmia or episodes are less than 24 h apart) or cardiac memo (if episodes are more than 24 h apart), an ECG if the patient is less than 50 years of age or is a murmur or left ventricular failure is detected clinically, or an exercise test if the palpitations are exercise related. Baseline blood tests to consider include a full blood count and erythrocyte sedimentation rate (or equivalent), urea and electrolytes, a blood glucose, and serum calcium. If there are any clinical symptoms or signs of thyrotoxicosis, check thyroid function tests.
Look for red flag symptoms that suggest serious underlying disease
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Investigation if family history of sudden death |
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TOPAbstractWhat the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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Management of relatives of victims of sudden cardiac death is outlined in the National Framework for Coronary Heart Disease. All first degree relatives of victims of sudden cardiac death who died under the age of 40 years, should be referred to a heart rhythm specialist for further evaluation. This may include tests of cardiac function and genetic testing.
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Ventricular ectopic beats |
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TOPAbstractWhat the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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Ventricular ectopic beats are additional broad QRS complexes, without p-waves, superimposed on a regular sinus rhythm (Figures 1 and 2). They are common and the patient may present will a feeling of ‘extra beats’ or palpitations. Although ventricular ectopics are usually of no clinical significance, they may rarely be a presenting feature of viral myocarditis. The following features require action:
- Frequent ectopics (more than 100 an hour) on ECG: refer urgently to cardiology
- R on T phenomenon on ECG: rarely ectopics can cause ventricular fibrillation - particularly if coinciding with the T wave of a preceding beat (‘R on T phenomenon’ – Figure 3). If this occurs frequently (more than 10 times a minute), then admit as an acute cardiac emergency.
- After myocardial infarct: ventricular extrasystoles after myocardial infarct are associated with increased mortality. Refer to cardiology.
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If there are no sinister features on ECG, explain the benign nature of the condition. Advise avoidance of caffeine, alcohol, smoking and fatigue. Beta-blockers, such as atenolol, can be helpful for patients unable to tolerate ectopics despite reassurance.
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Tachycardia |
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TOPAbstractWhat the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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Tachycardia is defined as a heart rate of greater than 100 beats per minute in an adult. Tachycardia may be physiological, in response to another condition or a drug, or pathological. If pathological, tachycardia may originate in the ventricles producing a broad complex tachycardia or be supraventricular resulting in a narrow complex tachycardia. Supraventicular tachycardia (SVT) may be regular (paroxysmal SVT) or irregular (atrial fibrillation).
Physiological sinus tachycardia
If a patient describes palpitations as fast, regular heart beats with no other associated cardiac symptoms, a physiological sinus tachycardia is the likely explanation. ECG done when the patient is not having symptoms should be normal. If the ECG is taken when the patient is having symptoms, it should be normal except for the rate. Reasons for physiological sinus tachycardia include infection (such as pneumonia), shock (for example due to bleeding or anaphylaxis), pain, exertion, anxiety and emotion. Drugs and certain foods and drinks, such as those containing caffeine or alcohol, may also cause sinus tachycardia and palpitations and patients who have recently undergone gastric surgery are prone to palpitations after eating due to rapid gastric emptying – a phenomenon known as dumping. Dumping usually settles within six months of surgery.
A physiological tachycardia also results from heart damage, for example, following a myocardial infarct (the heart must beat faster if the power is reduced to maintain the cardiac output) but tachycardia is then usually, but not always accompanied by other cardiac symptoms such as chest pain and other ECG changes.
Broad complex tachycardia
Ventricular tachycardia (VT) causes broad QRS complexes (each QRS complex occupies more than three small squares) at a rate of more than 100 beats a minute on ECG (Figure 4). VT may be silent, or present with palpitations, chest pain, breathlessness and/or collapse.
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VT is always a medical emergency. Call for emergency ambulance support. Give the patient oxygen whilst awaiting ambulance back up and consider giving intravenous amiodarone (300 mg) or lidocaine (1mg/kg). If the patient has no pulse, treat as a cardiac arrest. Patients with recurrent VT may require surgery, and/or insertion of an implantable cardioverter defibrillator.
The long QT syndrome (LQTS)
LQTS is a heart condition associated with prolongation of repolarization following depolarization of the cardiac ventricles. It is associated with syncope and sudden death due to ventricular arrhythmias, often associated with exercise or excitement. ECG characteristically has a prolonged QT interval. The genetic form can be inherited as an autosomal dominant or recessive form, and may be associated with syndactyly or neural deafness. Refer any patient with a family history of sudden cardiac death for specialist assessment and genetic counselling. Antenatal screening is possible if the gene mutation is known.
Paroxysmal supraventricular tachycardia (SVT)
Paroxysmal SVT is a reasonably common condition that may affect any age group including children. It is usually caused by an additional electrical connection between the atria and ventricles. Patients present with sustained episodes of fast regular palpitations lasting minutes to hours, and usually accompanied by other symptoms such as breathlessness, chest pain and/or near-collapse or collapse. Attacks tend to be recurrent, although there may be months or years between attacks, and may sometimes be precipitated by exertion. ECG during an attack shows a narrow QRS complex tachycardia (unless the patient has bundle branch block too) with a regular rate of 130–250 beats per minute (Figure 5). If the rate is exactly 150 beats per minute, suspect atrial flutter with 2:1 block.
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If you see a patient with paroxysmal SVT during an attack, get an ECG if possible. Try to terminate the attack (but ensure a defibrillator is available as rarely terminating the attack may provoke other arrhythmias). There are several ways to do this
- Carotid sinus massage – only attempt this on one side at a time. Do not attempt to do this if the patient is elderly, has ischaemic heart disease, is digoxin toxic, has a carotid bruit, or history of stroke or transient ischaemic attacks
- The Valsalva manoeuvre – ask the patient to take a breath and breathe out against a closed nose and mouth
- Ice on the face – this is particularly effective for children
- Pressure on closed eyes – avoid if the patient has any ocular conditions
If the attack continues, then admit the patient as a medical emergency. If the attack stops, or the diagnosis is from history alone or made on the basis of a report from an ambulatory ECG, then refer to cardiology for advice on further management enclosing a copy of the ECG during an attack if available. Refer urgently if the patient has chest pain, dizziness, collapse or breathlessness during attacks. Advise patients to avoid caffeine, alcohol and smoking as these can all precipitate attacks. Treatment options are beta-blockers (such as sotalol), verapamil or amiodarone. In some cases it is possible to ablate the re-entrant pathway.
Atrial fibrillation
Atrial fibrillation (AF) is a common disturbance of cardiac rhythm which may be episodic (paroxysmal) or chronic. It is characterized by a rapid irregularly irregular narrow QRS complex tachycardia with absence of p-waves (Figure 6). AF affects less than 1% of adults under the age of 60 years, but in excess of 8% of adults over 60 years, and is associated with a five times increase in the risk of stroke. AF has its own clinical domain within the Quality and Outcomes Framework and quality points are available for diagnosis of AF, maintaining a register of patients with AF and treating patients with aspirin or anticoagulants to decrease the stroke risk (Table 1). Although there is no cause found for AF in 12% of patients, AF may result from coronary heart disease, valvular heart disease (and in particular mitral valve disease), hypertension (especially if associated with left ventricular hypertrophy), and cardiomyopathy.
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In the community, acute episodes of AF may be precipitated by acute infection, high alcohol intake, acute cardiac events such as myocardial infarct or acute pericarditis, pulmonary embolus or hyperthyroidism. Acute episodes may be asymptomatic, or may cause palpitations, chest pain, fatigue, breathlessness, light headedness and/or syncope. An acute episode of AF may also present with a stroke or transient ischaemic attack. Patents in AF typically have an irregularly irregular pulse rate with an apex rate considerably higher than the radial pulse rate.
Management of AF aims to relieve symptoms, prevent thromboembolism and reduce risk of stroke and maintain cardiac function. Broadly there are two approaches, rate or rhythm control. These, together with reasons for choosing a particular course of action are outlined in Figure 7.
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Risk factors for stroke are:
- Patient age – the risk is increased in patients aged 65 years or older
- Previous history of ischaemic stroke or transient ischaemic attack
- Diabetes mellitus
- Cardiac failure
- Valve disease, and
- ECG showing left ventricular dysfunction or mitral valve calcification.
If a patient in AF is aged less 65 years and has no additional risk factors for stroke, give aspirin 75–300 mg daily as stroke prophylaxis. If a patient in AF is aged 65 years or more, or has one or more additional risk factors for stroke, consider anticoagulation with warfarin (maintaining the INR between 2 and 3) in preference to aspirin. A dose regimen for starting warfarin in the community is outlined in Table 2. Weigh the risks of prescribing warfarin against the benefits (Table 3), taking the patient's wishes, mental and physical health and social circumstances into consideration (Box 1).
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| Box 1. Clinical case scenario Mrs Smith is 88 years old and usually fit and well, but has been feeling a bit rough over the past couple of months and has noticed some palpitations. You examine her and find that she is in fast AF with a rate of 110 beats per minute. She does not appear to have any particular risk factors or cause for her AF, apart from mild hypertension for which she is taking ramipril, and had all her routine bloods including thyroid function tests done recently as part of her annual hypertension review. Your diagnosis is confirmed with an ECG. How should you manage her? In this case there are two major decisions to make:
This is the first presentation of lone AF in an other wise very fit lady, despite her age. Mrs Smith would be a suitable candidate for referral for cardioversion. However, when you discuss this with her she is reluctant to undergo the procedure and thinks that she is too old. She agrees to start atenolol to slow her heart rate. Mrs Smith is compus mentis and has no undue risk factors for gastrointestinal bleeding. In view of her age and hypertension, she falls into a high risk group for stroke. You discuss her risk of stroke, risk of gastrointestinal bleeding and the option of being treated with aspirin or warfarin. She is frightened of having a stroke as she was a carer for her husband who was disabled as a result of stroke. She is very keen to minimize her risk and agrees to start warfarin, even though she knows that this will entail regular monitoring blood tests.
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Risk of serious gastrointestinal bleeding in patients taking warfarin is approximately 9 per thousand patients per year. In addition, there is the inconvenience to the patient of having to have regular blood tests for warfarin monitoring. Stroke risks are cumulative, so if there is more than one additional risk factor (such as diabetes and hypertension), then benefits of anticoagulation increase. Patients undergoing cardioversion should be anticoagulated for 3 weeks prior to the procedure and for 4 weeks after successful cardioversion unless cardioversion is undertaken within two days of onset of AF.
For well patients (i.e. those with no history of valvular or ischaemic heart disease or left ventricular dysfunction) with infrequent episodes of symptomatic paroxysmal AF, consider a ‘pill-in-the-pocket’ approach to medication with a beta-blocker if systolic blood pressure is over 100 mmHg and resting heart rate is greater than 70 beats per minute. Provide a supply of beta-blockers (such as atenolol 50 or 100 mg tablets) to take just when symptomatic.
Refer for a specialist opinion (to cardiology, general medicine or care of the elderly) as an emergency if the patient has a fast rate of AF and is compromised by the arrhythmia (for instance has chest pain, hypotension or more than mild heart failure) or is a candidate for DC or chemical cardioversion. Refer through out-patients if there is uncertainty about diagnosis or treatment, or if symptoms are not controlled using standard treatment.
Atrial flutter
Patients with atrial flutter present in much the same way as patients with AF. ECG shows a regular saw-tooth baseline at a rate of 300 beats per minute with a narrow QRS complex tachycardia superimposed at a rate of 100 or 150 beats a minute. In primary care, manage in the same way as AF. Specialist drug treatment may differ.
Wolff–Parkinson–White (WPW) syndrome
In WPW syndrome, a congenital accessory conduction pathway (the bundle of Kent) is present between atrium and ventricle. WPW syndrome predisposes the patient to SVT and AF. ECG characteristically shows a short P-R interval followed by a slurred upstroke (delta wave) into the QRS complex (Figure 8). In all cases refer to cardiology. Treatment is with anti-arrhythmics and/or ablation of the accessory pathway.
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Bradycardia |
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TOPAbstractWhat the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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Bradycardia is defined as a heart rate of less than 60 beats per minute in an adult. It is often an incidental finding, but may present with faints or blackouts, drop attacks, dizziness, breathlessness or lack of energy. Examination shows slow pulse rate, normal or low blood pressure and sometimes signs of secondary heart failure. ECG usually confirms diagnosis. Ambulatory ECG may help with diagnosis of intermittent bradycardia (such as sick sinus syndrome). Consider checking thyroid function tests if symptoms or signs suggestive of hypothyroidism. If taking digoxin, check digoxin levels.
Sinus bradycardia
Constant bradycardia with p-waves on ECG and P-R interval of less than 0.2 seconds (one large square) – see Figure 9. May be normal in fit adults (for example, athletes) or due to drugs. Cardiac pathological causes include sick sinus syndrome and inferior myocardial infarct. Non-cardiac causes include hypothyroidism, hypothermia, raised intracranial pressure and jaundice. If symptomatic, admit for urgent assessment. If asymptomatic and heart rate is less than 40 beats per minute despite treatment of reversible causes, refer for a cardiology opinion.
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Atrio-ventricular (AV) node block or heart block
Heart block has many causes – ischaemic heart disease, drugs (such as verapamil and digoxin), myocarditis, cardiomyopathy and Lyme disease (rare). There are three main types of heart block:
- First degree block: the ECG shows a fixed P-R interval of greater than 200 ms (1 large square) – Figure 10
- Second degree block: two types are described. In Mobitz type I (Wenckebach) heart block, the ECG shows a progressively lengthening P-R interval followed by a dropped beat (Figure 11). In Mobitz type II heart block, the ECG shows a constant P-R interval with regular dropped beats (e.g. 2:1 – every second beat is dropped) – Figure 12. Mobitz type II block is often associated with drug toxicity
- Third degree or complete heart block: the ECG shows P-P intervals to be constant and R-R intervals to be constant, but not related to each other – Figure 12
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Untreated second and third degree heart block have a mortality of around 35%. Refer all patients to cardiology even if asymptomatic. If symptomatic (systolic blood pressure of less than 90 mmHg, left ventricular failure, heart rate of less than 40 beats per minute) admit as an emergency. Give 3 mg intravenous atropine (once only) and oxygen (if available) whilst awaiting admission.
Stokes Adams attacks
A Stokes Adams attack is a cardiac arrest due to AV block. Attacks result in sudden loss of consciousness and often some limb twitching due to cerebral anoxia. The patient becomes pale and pulseless but respiration continues. Attacks usually last about 30 s but are occasionally fatal. On recovery the patient becomes flushed. Refer to cardiology if suspected.
Sick sinus syndrome
Sick sinus syndrome is a common condition amongst elderly patients due to sinus node dysfunction causing bradycardia. Bardycardia may be associated with asystole, sinoatrial block (complete heart block), AF or SVT alternating with bradycarida (tachy/brady syndrome). If the patient is symptomatic, the heart rate is less than 40 beats per minute or there are pauses of greater than three seconds on ECG (Figure 13), refer to cardiology for pacemaker insertion.
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Pacemakers |
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TOPAbstractWhat the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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Pacemakers electrically stimulate the heart to beat. They may be used to treat symptomatic bradycardia, and second or third degree heart block. They may also be used to suppress resistant tachycardia. The pacemaker box is attached under the skin of the chest, usually medial to the left axilla, under local anaesthetic. Wires are fed via the great veins of the chest to the heart under X-ray and/or ultrasound guidance. Pacemakers are classified according to:
- The chamber paced - atrium, ventricle or both (‘dual’)
- The chamber sensed - atrium, ventricle or both (‘dual’)
- The mode of response to sensing - inhibited output, triggered, inhibited and triggered (‘dual’).
Therefore, a VVI pacemaker paces the ventricle (‘V’), and senses the ventricle (‘V’). In inhibited mode (‘I’), if the ventricle beats spontaneously the pacemaker will not fire. If the pacemaker is in operation a pacing ‘spike’ (vertical line) is seen on ECG. In devices pacing on demand a spike will not be seen if the natural rate is in excess of the rate set on the pacemaker.
Pacemakers last between 7 and 15 years. Regular checks are made by pacemaker clinics to ensure the pacemaker remains operational. Reprogramming through the skin is possible. Batteries can be changed via a small surgical procedure under local anaesthetic. Patients may drive with a pacemaker, but they should inform the DVLA and their insurance company and stop driving for a month after insertion. After death, pacemakers must be removed before cremation can take place. A fee is payable.
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References |
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TOPAbstractWhat the GP curriculum...Assessment of palpitationsInvestigation if family history...Ventricular ectopic beatsTachycardiaBradycardiaPacemakersReferences |
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– Implantable cardioverter defibrillators (ICDs) for the treatment of arrhythmias - a review of guidenace no.11. (2006) Accessed via http://www.nice.org.uk/guidance/index.jsp?action=byID&r=true&o=11566 [date last accessed 30.11.07].
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