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A D _ 0 3 3 _ _ _ MA R 1 3 _ 0 9 . p d f Pa ge 3 3 5 / 3 / 0 9 , 4 : 2 6 PM HowtoTreat www.australiandoctor.com.au PULL-OUT SECTION inside COMPLETE HOW TO TREAT QUIZZES ONLINE (www.australiandoctor.com.au/cpd) to earn CPD or PDP points. Initial assessment Cardiac monitoring strategies Case studies The authors DR SUSAN CORCORAN, cardiologist, Caulfield Hospital, Alfred Health, Caulfield, Victoria. DR DAVID LIGHTFOOT, emergency physician, Monash Medical Centre, Clayton, Victoria. Palpitations Background PALPITATIONS are a common symptom in primary practice. The term is used to describe an uncomfortable awareness of the heart beating and does not necessarily indicate that the patient has an arrhythmia. For a patient complaining of palpitations, the initial assessment is guided by three principles: • Do the palpitations represent an arrhythmia? • Are the palpitations a symptom of associated heart disease? News • Are the palpitations a symptom of comorbid non-cardiac disease? Initial assessment of patients with palpitations should always involve two parallel courses of investigation: investigating the palpitations themselves (often involving cardiac-monitoring strategies); and assessing for and managing underlying cardiac and non-cardiac conditions that may result in palpitations and require management in their own right. Patients who present with palpita- tions will most frequently be found to have sinus rhythm, sinus tachycardia, or atrial or ventricular ectopy as the cause of their symptoms. However, 20-30% of patients will be found to have rhythms requiring further investigation and/or management. Most frequently these will be atrial fibrillation or other forms of supraventricular tachycardia. Ventricular tachycardia rarely causes palpitations, and more commonly presents with syncope or presyncope. Comment Prognosis of a patient presenting with palpitations in general relates not to the cause of the palpitations themselves but to the prognosis of the underlying cardiac and non-cardiac conditions with which they are associated. A common exception to this rule is sustained atrial arrhythmias (atrial fibrillation and flutter), which are associated with risk of stroke. The risk of stroke however, increases with the number of comorbid conditions. CPD points cont’d next page Classifieds www.australiandoctor.com.au – medicine at your fingertips www.australiandoctor.com.au 13 March 2009 | Australian Doctor | 33 A D _ 0 3 4 _ _ _ MA R 1 3 _ 0 9 . p d f Pa ge 3 4 5 / 3 / 0 9 , 1 1 : 4 5 AM HOW TO TREAT Palpitations Initial assessment Aim THE aim of the initial assessment is to: • Make a clinical diagnosis as to the most likely cause of the palpitations based on: — description of the symptoms. — the patient’s age. — comorbidities. • Identify features in the history that indicate the patient may be at risk of a serious cause for the palpitations, for which early or emergent cardiology referral is indicated: — palpitations in association with syncope or presyncope. — onset of palpitations during exercise. — sustained palpitations in association with known structural heart disease. — sustained palpitations in association with other symptoms suggestive of significant heart disease, eg, dyspnoea or angina. History of the symptoms A clinical diagnosis as to the likely cause of a patient’s palpitations can often be made by the description of the palpitations. In general it is helpful to ask: • In what circumstances did the palpitations occur? • Did they commence when lying, sitting or standing? • Did they come on at rest or with exercise? • Were they regular or irregular? • How fast were they? • Did they come on suddenly? • Did they stop suddenly? • How often are they occurring? • Is there any relationship between medication, alcohol or drugs and the palpitations? • Could the patient have been dehydrated? • If the patient was feeling anxious, was this before or after the onset of the palpitations? Remember that palpitations are an uncomfortable awareness of the heart beating and do not always reflect a tachyarrhythmia. Patients who are dehydrated or anxious may be uncomfortably aware of a resting pulse rate of 80-100 beats/minute in sinus rhythm. Many medications can cause sinus tachycardia as a side effect (table 1). It is often helpful to tap out different heart rates to obtain an indication of how fast the rhythm was that the patient experienced. How does sinus rhythm/sinus tachycardia feel when it causes palpitations? 34 Table 1: Medications that can cause sinus tachycardia Medications with anticholinergic actions Agents acting on the central nervous system: • tricyclic antidepressants • antipsychotics: — chlorpromazine — clozapine — haloperidol/droperidol — quetiapine — olanzapine Agents used for bladder function disorders: • oxybutynin • solifenacin • tolterodine Agents used for the GI system: • atropine • hyoscine compounds • hyoscyamine • prochlorperazine Antihistamines (promethazine) Bronchodilators (ipratropium) Bronchodilators Beta agonists, eg, salbutamol Theophylline Antihypertensives Dihydropyridine calcium antagonists: • felodipine • amlodipine • lercanidipine Diuretics (dehydration) Clonidine Hydralazine Cold and flu remedies, eg, pseudoephedrine, ephedrine Weight-loss remedies, eg, sympathomimetic appetite suppressants Stimulants Caffeine Nicotine Amphetamines Cocaine Table 2: Likely causes of palpitations according to age and underlying heart disease Underlying heart disease Likely cause of palpitations Nil – age <50 Sinus rhythm, sinus tachycardia, atrial or ventricular ectopy Re-entrant supraventricular tachycardia Nil – age >50 As above plus atrial arrhythmias Ischaemic heart disease Sinus rhythm, sinus tachycardia, atrial or ventricular ectopy Atrial arrhythmias (Ventricular tachycardia) Cardiomyopathy Sinus rhythm, sinus tachycardia, atrial or ventricular ectopy Atrial arrhythmias (Ventricular tachycardia) Hypertensive heart disease, valvular heart disease Sinus rhythm, sinus tachycardia, atrial or ventricular ectopy Atrial arrhythmias Sinus rhythm may be experienced as palpitations when the rate is excessive for the level of exertion at the time it occurs. Sinus rhythm is usually experienced as palpitations with gradual onset and offset. Patients most commonly complain of symptoms occurring at rest, sitting or lying or with prolonged standing. The rhythm is regular but may feel forceful. When tapped out it is usually at a rate of 80-120 beats/minute. Rarely, patients who have conditions associated with an inappropriate sinus tachycardia can develop sinus rates up to 160 beats/minute while standing at rest. How do ectopic beats feel when they cause palpitations? Atrial and ventricular ectopics are often experienced as a flutter followed by a pause then a big thump. Ventricular ectopics in particular are experienced as a ‘skipped beat’ and may result in a pulse deficit. This is because the ectopic comes early in the cardiac cycle, resulting in a short ventricular filling time | Australian Doctor | 13 March 2009 Table 3: Non-cardiac diseases predisposing to palpitations Condition Thyrotoxicosis Anaemia Acute and chronic lung disease, pulmonary hypertension Systemic infection or or inflammation Non-cardiac surgery Likely cause of palpitations Sinus tachycardia, atrial arrhythmias Sinus tachycardia Sinus tachycardia, atrial arrhythmias Sinus tachycardia, atrial arrhythmias, atrial or ventricular ectopy Sinus tachycardia, atrial arrhythmias, atrial or ventricular ectopy and therefore a low volume output for that beat. Resetting of the sinus pacemaker results in a pause after the ectopic. The post-ectopic beat therefore has a long filling time and thus it produces a large volume output — the thump. Ventricular ectopics often cause an uncomfortable feeling in the throat and a need to cough, due to a reversal of the normal activation pattern of the heart, resulting in contraction of the atria against closed atrioventricular valves and increased peripheral and pulmonary venous pressures for that beat. Patients are most commonly aware of ectopic beats when sitting or lying quietly, such as when driv- ing the car, sitting reading, watching television or in bed at night. They may be more symptomatic if the patient is dehydrated and can occur in association with intercurrent illnesses such as respiratory illnesses. How does atrial fibrillation feel when it causes palpitations? Atrial fibrillation does not always cause palpitations; some patients may be entirely asymptomatic. When it is symptomatic patients are usually aware of a sudden onset and offset of symptoms. Many patients are aware of the irregularity of the rhythm, particularly if it is tapped out for them. Onset is unrelated to pos- www.australiandoctor.com.au Atrial and ventricular ectopics are often experienced as a flutter followed by a pause then a big thump. ture, although in a subset of patients episodes begin more frequently at night. The duration can vary considerably. How does re-entrant supraventricular tachycardia feel when it causes palpitations? Re-entrant supraventricular tachycardia is of sudden onset and offset. It is a rapid regular rhythm, commonly 170-200 beats /minute. It is often associated with a tight feeling in the throat and chest, due to simultaneous activation of the atria and ventricles. Patients may have discovered that the Valsalva manoeuvre can occasionally terminate the arrhythmia. How does ventricular tachycardia feel when it causes palpitations? Sustained ventricular tachycardia rarely presents with palpitations unless it is one of the forms of ventricular tachycardia that occur in normal hearts, such as right ventricular outflow tract (RVOT) ventricular tachycardia . In most other cases, ventricular tachycardia occurs in association with structural heart disease and presents with syncope, presyncope or shortness of breath due to the loss of atrioventricular synchrony. Non-sustained ventricular tachycardia is often felt in the throat and may be followed by a pause and thump, as with ventricular ectopy. Clinical history A detailed past history is essential. The past history may give an indication as to the cardiac rhythms a patient is at risk of developing (table 2). Patients with a past history of heart disease are at increased risk of developing cardiac arrhythmias. Non-cardiac diseases may also predispose patients to cardiac arrhythmias, for example, atrial fibrillation in thyrotoxicosis. A family history may indicate rare but serious inherited rhythm disorders such as long-QT syndrome, particularly if there is a family history of early unexplained sudden cardiac death. Medications, over-thecounter preparations, recreational drugs (including high caffeine intake from coffee and energy drinks and high nicotine intake) may cause sinus tachycardia or trigger arrhythmias such as atrial fibrillation or re-entrant supraventricular tachycardia in a predisposed patient. Age is also a helpful risk stratifier. Younger adults A D _ 0 3 5 _ _ _ MA R 1 3 _ 0 9 . p d f (<50) are most likely to have normal hearts, therefore they are more likely to have the rhythms that cause palpitations in normal hearts. These include sinus rhythm, sinus tachycardia, and atrial or ventricular ectopy as a cause for their palpitations. This group of patients may also present with re-entrant supraventricular tachycardia. Older patients and those with a past history of heart disease are at greater risk of having a more serious cause for their palpitations. They are less likely to have a normal heart and are likely to have a greater number of comorbid conditions. Pa ge 3 5 5 / 3 / 0 9 , 1 1 : 4 7 AM Figure 1: Sinus rhythm with a short PR interval, delta waves and abnormal QRS axis as seen in Wolff-Parkinson-White syndrome. Clinical examination Unfortunately, most patients present between episodes of palpitations. The purpose of the clinical examination, in the absence of the symptomatic rhythm, is to assess for underlying cardiac or non-cardiac conditions that predispose the patient to particular arrhythmias (see tables 2 and 3). Blood pressure and pulse should be taken supine and after standing for five minutes to assess for postural hypotension or tachycardia. The patient should be assessed for: • Clinical signs of current systemic infection or inflammation. • Clinical signs of anaemia or thyroid disease. • Cardiorespiratory examination to assess for: — signs of valvular heart disease (murmurs). — signs of heart failure Figure 2: Sinus tachycardia with frequent unifocal ventricular ectopics, each followed by a compensatory pause. (elevated jugular venous pressure, enlarged heart, oedema or pulmonary congestion). — signs of chronic lung disease. An ECG must be performed on all patients presenting with palpitations. The ECG may indicate underlying electrical disorders or evidence of heart disease that will predispose the patient to certain arrhythmias. For example, it may reveal the short PR interval and delta waves of Wolff-Parkinson-White syndrome (figure 1), which predisposes the patient to reentrant supraventricular tachycardia. It may perhaps demonstrate left ventricular hypertrophy and left atrial enlargement — predisposing the patient to atrial fibrillation. Occasionally you may capture the symptomatic rhythm, such as ventricular ectopics (see figure 2). Investigations Baseline investigations An FBC, serum electrolytes, magnesium and thyroid function studies are a simple set of screening tests commonly performed in a patient who presents with palpitations. Further investigations Further investigation is performed for two purposes: to attempt to document the cardiac rhythm at the time of symptoms; and to further assess for underlying cardiac or non-cardiac disease, if indicated, based on the initial history, ECG and baseline bloods. Cardiac monitoring strategies THE purpose of cardiac monitoring strategies is to obtain symptom –rhythm correlation. The technique used will depend on the frequency of symptoms. Holter monitoring Holter monitoring involves continuous cardiac monitoring for 24hours. The patient is unable to shower during the time period and presses a button to mark symptoms. Holter monitoring is widely available. It is helpful for symptoms that are occurring daily. It can be helpful to confirm a clinical diagnosis of ventricular ectopy and to assess the frequency of ectopy (see box ‘How to treat ventricular ectopy’, page 36). Cardiac event monitoring Event monitors are usually worn for 1-2 weeks and are useful if the patient’s symptoms are occurring weekly. They are less widely available than Holter monitors and are associated with a higher incidence of technical problems but are often very useful in diagnosing palpitations. Cardiac event monitoring can be It can often be difficult to obtain symptom–rhythm correlation in patients with infrequent symptoms. performed in two different ways. The first involves continuous monitoring for a period of a week. The patient is able to remove ECG electrodes for showering and reapply new ones afterwards. The monitor has a continuous loop recording mechanism. The patient presses the button when symptoms occur. The device freezes a variable amount of ECG pre- and post-activation. This information can sometimes then be transmitted over a telephone line. Some event monitors of this type also store automatically detected but asymptomatic arrhythmias. A second type of monitor is placed against the chest during symptoms, which it then records for a variable duration — usually 30-90 seconds. This device is not useful for very brief palpitations, as they will have finished by the time the device is applied and therefore will not be captured. Monitoring in the patient with infrequent palpitations Holter monitoring is generally not helpful in patients whose symptoms occur infrequently. However, www.australiandoctor.com.au on occasion it may reveal asymptomatic rhythms that may require treatment in their own right, such as prolonged episodes of atrial tachyarrhythmias. Long-term (three years) implantable cardiac monitors are available that continuously record the patient’s heart rhythm and can store arrhythmias automatically or during the patient’s symptoms. However, these are usually reserved for investigating patients with syncope. Alternative strategies depend on the duration of the symptoms on each occasion. These include giving the patient a request form for an ECG to be performed during symptoms. Depending on the severity of the symptoms and the comorbidities present, the patient may be instructed to call an ambulance or present to the emergency department with the symptoms. It can often be difficult to obtain symptom–rhythm correlation in patients with infrequent symptoms. A clinical diagnosis may be made on the basis of the history and comorbidities. Further investigation then focuses on risk stratification. For example, a patient who gives a history consistent with paroxysmal atrial fibrillation will need to be assessed for exacerbating factors such as hypertension that will require treatment. An assessment for stroke risk and need for anticoagulation will also need to be made. Electrophysiological testing Electrophysiological testing is an invasive study of the cardiac electrical system performed in a cardiac catheterisation laboratory. The heart is accessed via the venous system, most commonly using the femoral vein. Electrode catheters that can both record cardiac signals and stimulate the heart are passed via the veins to the heart and positioned predominantly within the right heart chambers. The left side of the heart may be accessed, when required, by crossing the interatrial septum. Electrophysiology studies are used to examine the electrical system of the heart and to assess the patterns of cardiac activation cont’d next page 13 March 2009 | Australian Doctor | 35 A D _ 0 3 6 _ _ _ MA R 1 3 _ 0 9 . p d f Pa ge 3 6 5 / 3 / 0 9 , 1 1 : 4 8 AM HOW TO TREAT Palpitations from previous page How to treat ventricular ectopy in the patient, thus determining if they have the substrate for a particular arrhythmia. Attempts are made to induce the suspected arrhythmia using pacing manoeuvres and medications. Ablation, using radiofrequency current or cryotherapy, may be used to destroy a small area of cardiac tissue critical to the maintenance of an arrhythmia. Depending on the arrhythmia this can often be curative. In other circumstances it may be part of a broader management strategy that includes medications and/or devices such as pacemakers and defibrillators. An electrophysiological study (EPS) may be performed when assessing a patient with palpitations when the history is suggestive of an arrhythmia known to be inducible during an EPS. On other occasions the EPS is performed with a view to proceeding to ablation after a diagnosis has been made. Echocardiography While the echocardiogram will not identify the rhythm causing the palpitations, it is a useful tool for risk stratification. The patient with a normal echocardiogram and normal ECG, with symptoms occurring at rest, is at very low risk of having an adverse outcome and likely to have a benign cause for their palpitations. Exercise stress testing Exercise stress testing is generally not indicated for investigating palpitations unless they occur with exertion or immediately post exertion, or the patient also has symptoms of ischaemic heart disease. In these circumstances the aim of test- • Although generally benign, ventricular ectopy can occur in association with underlying heart disease • Ventricular ectopics themselves are rarely the target of treatment • Prognosis relates to the presence and severity of underlying heart disease • Management is focused on: — Excluding coexistent heart disease — Optimising management of coexistent heart disease — Optimising cardiovascular risk-factor management • All patients with symptoms suggestive of ventricular ectopy require an ECG and clinical cardiovascular examination • Baseline bloods are generally also indicated Further investigation: — Holter or event monitoring can be helpful to confirm ventricular ectopy as the mechanism of the patient’s symptoms and to assess the frequency of ventricular ectopy Benign ventricular ectopy • Infrequent ectopics (<0.1% of beats) occurring at rest in association with a normal clinical examination and baseline ECG are considered benign • Echocardiography is not indicated in these circumstances but can be useful for providing further reassurance, particularly in an anxious patient • Stress testing is not indicated in these circumstances unless the patient has other symptoms concerning for ischaemic heart disease • Management of benign ventricular ectopy: — Patient reassurance — Identify and remove triggering factors (caffeine, alcohol, nicotine, dehydration, stress) — If very symptomatic a beta blocker can be trialled. Anti-arrhythmic agents are rarely used and may be harmful When is further investigation/referral indicated? • Historical or patient factors may indicate serious underlying heart disease associated with the ectopics. Further investigation and cardiology referral is indicated for patients with the following features: — Ventricular ectopy occuring with exertion or immediately post exertion — Ventricular ectopy associated with syncope or presyncope — Ventricular ectopy that is very frequent (>1% of beats on Holter monitoring) — A baseline ECG that is significantly abnormal — When advice regarding optimisation of management of known heart disease is required — When previously undiagnosed heart disease is discovered in the course of investigation for the palpitations • In these circumstances further investigation is targeted at assessing for underlying heart disease or reassessing patients with known heart disease. This will allow for optimal management of the underlying condition with which the ventricular ectopy is associated — If not performed recently, echocardiography is indicated to assess cardiac structure and function — Stress testing (± nuclear/echocardiographic imaging) may be performed to assess for ischaemic heart disease or rare arrhythmic disorders (eg, long QT syndrome) — Coronary angiography may be required if significant coronary disease is suspected after the initial evaluation ing is to reproduce the palpitations or assess for coexistent ischaemic heart disease that requires treatment in its own right. Cardiac perfusion imaging, coronary angiography, cardiac CT or MRI While these are not required for How to manage common findings on Holter monitoring Ventricular ectopics (see box at left) Atrial ectopics • Rare atrial ectopics (<0.1%) are a common normal finding • More frequent atrial ectopy is found less commonly. It does not require treatment unless the patient is symptomatic Brief supraventricular tachycardia episodes • Brief (<1 minute) supraventricular tachycardia episodes are a common normal finding, particularly in patients over 50 • Infrequent episodes require no specific treatment • Frequent episodes can indicate a propensity to longer episodes of atrial arrhythmias at other times. They should prompt assessment of modifiable risk factors for atrial fibrillation and assessment of thromboembolic risk • Aspirin may be started if not contraindicated. Anti-arrhythmic or AV-node blocking agents may be initiated if symptomatic Non-sustained ventricular tachycardia • This is an uncommon finding on Holter monitoring • Structural heart disease should be excluded • Assessment of cardiac function and cardiology referral is appropriate investigating palpitations, initial investigation of the patient may reveal cardiac conditions that require further assessment using these modalities. Authors’ case study 1 MR AB, 65, presents complaining of palpitations. He has noticed them on and off for the past few weeks. They can occur at any time and are not related to posture or exercise. He cannot identify any particular precipitating or relieving factors. They can last from a few seconds up to 20 minutes. They are rapid but he is not sure if they are regular or irregular. He feels uncomfortable with the palpitations and prefers to sit still with them. He does not feel lightheaded or faint when they occur. He has never had chest pain and has normal exercise tolerance. Symptoms are currently occurring a few times a week. Mr AB has a past history of hypertension for 15 years and type 2 diabetes for five years. He stopped smoking five years ago and has a 20pack-year history of smoking. His current medications are perindopril/indapamide 4mg/1.25mg mane, aspirin 100mg daily and metformin 500mg bd. Mr AB’s blood pressure is 36 Figure 3: ECG demonstrating criteria for left ventricular hypertrophy and left atrial enlargement. 150/90mmHg on examination. He is in sinus rhythm with a pulse rate of 88 | Australian Doctor | 13 March 2009 beats/minute. His cardiovascular examination is normal. His ECG demonstrates cri- teria for left ventricular hypertrophy and left atrial enlargement (figure 3). www.australiandoctor.com.au Approach to management The approach in this patient is to determine the cause of his palpitations while simultaneously addressing his overall cardiovascular risk: A D _ 0 3 7 _ _ _ MA R 1 3 _ 0 9 . p d f Pa ge 3 7 5 / 3 / 0 9 , 1 1 : 4 8 AM successful at capturing his rhythm during his usual symptoms. Approach to management of atrial fibrillation/flutter Atrial fibrillation and flutter are some the most complex rhythms to manage. When assessing a patient with these arrhythmias there are four key principles: 1. Why? What are the predisposing cardiac and non-cardiac factors that require treatment in this patient, eg, pneumonia, thyroid disease, uncontrolled hypertension? 2. Anticoagulation? • Are there any serious contraindications to anticoagulation? • If no serious contraindications, which anticoagulant should be used? Use the CHADS2 scoring table below for patients with non-valvular atrial fibrillation/flutter. Condition Points C Congestive heart failure or LVEF <35% 1 H Hypertension (or treated hypertension) 1 1 A Age ≥75 years D Diabetes 1 Prior TIA or stroke 2 S2 The S2 indicates that a history of prior TIA or stroke earns the patient two points. Points are added to achieve the CHADS2 score. Recommendations based on the score are shown below: CHADS2 score Risk Anticoagulation therapy 0 Low Aspirin 81-325mg/day 1 Moderate Aspirin 81-325mg/day or warfarin (INR 2.0-3.0) ≥2 Moderate or high Warfarin (INR 2.0-3.0) 3. Rate control This is the initial focus of management after deciding about anticoagulation. 4. Rhythm control Managing a patient with atrial fibrillation will include decisions about maintenance of sinus rhythm. This may involve a combination of strategies over time. These decisions will often be made in consultation with a cardiologist or physician. • Mr AB has the known risk factors for cardiovascular disease of age, male gender, hypertension, diabetes and prior smoking. A family history and fasting lipids will complete this assessment. • After this initial assessment he is at least at moderate risk of a cardiovascular event in the next five years. • Because of his comorbidities, including evidence of cardiac end-organ damage due to hypertension, he is at risk of serious cardiac arrhythmias, in particular, atrial fibrillation. Atrial fibrillation as a cause of his palpitations would place him at risk of thromboembolic events (see box, Approach to management of atrial fibrillation/flutter). • A ventricular arrhythmia is less likely as the cause of his symptoms. However, evaluating his ventricular function (with an echocardiogram) will assist in the risk assessment for ventricular arrhythmias and aid with further management. This patient should be referred early for specialist cardiology care. In addition to arranging an early cardiology referral: • Baseline blood tests including thyroid function tests should be performed. Fasting lipids and assessment of diabetic control (HbA1C and testing for microalbuminuria) will assist in further assessing his cardiovascular risk. • As his hypertension control is suboptimal, antihyper- tensives should be added or the dose increased. • If no contraindications exist, lipid-lowering therapy should be started after lipid estimations, baseline creatine kinase and LFTs are performed. In the setting of diabetes the target LDL cholesterol is ≤ 2.0 mmol/L, HDL >1.0mmol/L and triglycerides <1.5 mmol/L. Further assessment of the palpitations Mr AB is most likely to have a paroxysmal atrial arrhythmia as the cause of his intermittent palpitations because: • The sudden onset and offset is against sinus tachycardia. • The palpitations are rapid and the description is not Progress consistent with ectopics. • Re-entrant supraventricular tachycardia uncommonly first presents in this age group. • A ventricular arrhythmia is very unlikely in the absence of significant structural heart disease. Cardiac monitoring is likely to be helpful in these circumstances, as the palpitations are occurring fairly frequently. Because the palpitations are occurring a few times a week, a 24-hour Holter monitor has about a 30% chance of capturing his rhythm at the time of symptoms. An event monitor is much more likely to be helpful. Given the frequency of symptoms, a monitor worn for 12 weeks is very likely to be Mr AB has normal baseline electrolyte levels, FBC and thyroid function. His HbA1C is 7% and there is no microalbuminuria. His total cholesterol is 6.0mmol/L, LDL 4.5mmol/L and HDL 1.1mmol/L, with triglycerides 2.0 mmol/L. He is referred to a diabetic educator for further dietary management of diabetes and hypercholesterolaemia and started on a statin. His blood pressure on review is 130/80mmHg after initiation of amlodipine 5mg daily. A cardiac echo reveals mild left ventricular hypertrophy and moderate left atrial enlargement but normal ventricular size and function and no significant valvular heart disease. Cardiac event monitoring during brief palpitations reveals paroxysms of atrial fibrillation with a ventricular rate of 150 beats/minute. Mr AB is seen by a cardiologist, who adds sotalol 80mg bd for both rhythm and rate control of atrial fibrillation. Amlodipine is stopped because of concerns he may become hypotensive. Although his atrial fibrillation has been short-lived thus far, future episodes may last longer and are likely to be less symptomatic with initiation of sotalol. Sotalol will only prevent the recurrence of atrial fibrillation long term in 40% of people. Therefore, given a CHADS 2 score of 2 (see box, above), he is started on warfarin for prophylaxis against stroke, aiming for an INR of 2-3. Aspirin is continued for thromboprophylaxis against other vascular events. Authors’ case study 2 MS CD, 35, presents with a history of palpitations, occurring on and off over the last six weeks. They make her feel very uncomfortable. She often has to cough with the episodes and feels her heart stops and then cuts back in with a big thump. She feels strange with the episodes but does not feel as though she will faint. She is very anxious, as the palpitations have occurred a number of times while driving her children to school. She has also noticed them when reading in bed at night. She feels otherwise well and exercises three times a week at the gymnasium without any symptoms. She occasionally notices the palpitations driving to or from the gym but never when exercising or immediately after exercise. Currently symptoms are occurring daily. Ms CD does not smoke. She drinks two glasses of wine three nights a week. Her only current replacement in his 70s. On examination Ms CD’s blood pressure in 120/65mmHg and her pulse is 75 beats/minute and regular. Her cardiovascular examination is unremarkable. An ECG is performed: the trace shows sinus rhythm with a normal QT interval. Approach to management This history is consistent with benign ventricular ectopy. This patient has no concerning features in her history or on examination. She has a clinically normal heart and a normal ECG. She requires minimal investigations and reassurance after these investigations are confirmed to be normal. Investigations medication is the oral contraceptive pill. She has no other medical problems. There is no family history of arrhythmias and no one in the family has died suddenly. Her grandfather had a heart valve www.australiandoctor.com.au • Baseline electrolytes, FBC and thyroid function studies • No further investigations are necessary — this is a classic history. However, patients are often anxious to have the diagnosis ‘proven’. In these circumstances, if palpitations are occurring daily, a Holter monitor can be useful to demonstrate the ectopy at the time of the patient’s symptoms. Palpitations occurring weekly can usually be documented on an event monitor. • Echocardiography is not indicated when the patient has infrequent ectopy and a normal baseline ECG and examination. However, it can be helpful for reassuring the patient that they have a normal heart. Management • Reassurance that, although very uncomfortable, the ectopy is benign. • Explain the mechanism whereby ectopics cause a ‘flutter, pause, thump’. • Try to identify precipitating factors such as dehydration, caffeine or over-the-counter preparations containing stimulants such as pseudoephedrine. cont’d next page 13 March 2009 | Australian Doctor | 37 A D _ 0 3 8 _ _ _ MA R 1 3 _ 0 9 . p d f Pa ge 3 8 5 / 3 / 0 9 , 1 1 : 5 1 AM HOW TO TREAT Palpitations Summary Authors’ case study 3 MS EF, 23, presents with three episodes of palpitations over the past six months. The palpitations are very rapid and she thinks they are regular. They have come on after an argument with her now exboyfriend, on another occasion when drinking strong coffee to stay awake while studying late at night, and recently the day after a ball where she drank a lot of alcohol. She thinks they start and stop suddenly, and they have lasted up to one hour. She feels very anxious with the palpitations. They make her feel tight in the chest and throat. Ms EF is single and lives in a share house; her family live interstate. She is in her fourth year of university studying arts/law. She also works part time as a waitress. She has been under a lot of stress lately because of financial and study pressures. She recently broke up with her boyfriend of two years. Between episodes she feels well and attends spin classes at the local gym three times a week. Ms EF is otherwise well. She had childhood asthma and occasionally experiences symptoms now after viral infections. There is no family history of heart disease and her parents are well. Her only current medication is the oral contraceptive pill. On examination her blood pressure is 115/65mmHg and she is in sinus rhythm with a rate of 65 beats/minute. Her cardiovascular examination is normal. An ECG is in sinus rhythm at a rate of 65 beats/minute and is normal. FBC, electrolytes and thyroid function are normal. Approach to management This young woman has a normal ECG and clinically normal heart. She has no cardiac symptoms between episodes. This history is suggestive of either: • Sinus tachycardia — the palpitations have occurred in circumstances of stress, dehydration and caffeine excess. — the palpitations are regular. • Re-entrant supraventricular tachycardia — the palpitations are of sudden onset and offset. — they are rapid and regular and cause tightness in the throat. — they are triggered by circumstances of increased sympathetic activity. Investigations Cardiac monitoring The palpitations are very infrequent so monitoring techniques are unlikely to be useful. As the palpitations have lasted for up to one hour, Ms EF could be given an ECG 38 Figure 4. Atrioventricular nodal re-entrant tachycardia. Fast pathway Right atrium Bundle of His AV node Left bundle branch Slow pathway Right bundle branch Figure 5. Atrioventricular re-entrant tachycardia. A: Orthodromic tachycardia – the impulse follows the normal direction of conduction then re-enters the atria via an accessory electrical pathway. B: Antidromic re-entry – the circuit occurs in the reverse direction. (See box below for further description.) A. B. Orthodromic atrioventricular re-entry Antidromic atrioventricular re-entry Accessory pathway Accessory pathway • Palpitations are a common symptom. • An ECG should be performed in all patients with palpitations. • Frequency of symptoms should be considered before arranging cardiac monitoring. Holter monitoring is not useful unless the symptoms are occurring daily. • Patients at risk of an adverse outcome can be identified by assessing for comorbid cardiac and non-cardiac conditions. • A cardiac echo is a useful tool for risk-stratifying patients with palpitations. • Patients under 50 with a normal ECG and examination, with palpitations occurring at rest and not associated with syncope or presyncope, usually have a very good prognosis. • Older patients and those with a significantly abnormal ECG or examination or known structural heart disease are more likely to have an adverse outcome. An early cardiology referral should be made. Further reading request form to have an ECG with symptoms, or requested to present to the emergency department with the palpitations. (However, she should not drive herself.) Echocardiography Although not specifically indicated in these circumstances, an echocardiogram can provide further reassurance that there is unlikely to be a serious underlying cause for the palpitations. This can be particularly useful in a situation where it may take some time to confirm the clinical diagnosis. Electrophysiological studies This is a circumstance when referral to a cardiac electrophysiologist with a view to an EPS would be warranted. There are many features of this history to suggest reentrant supraventricular tachycardia as a mechanism. An EPS would determine if the patient has the substrate for this arrhythmia, and the arrhythmia can usually be induced if it is the cause. Curative ablation could then be offered. | Australian Doctor | 13 March 2009 Re-entrant supraventricular tachycardia This is the likely cause of palpitations in a patient who presents with sudden onset of rapid regular palpitations. It occurs in patients with structurally normal hearts who have the electrical substrate for these rhythms. There are two common types. Atrioventricular nodal re-entry • This is the most common cause of re-entrant supraventricular tachycardia. Despite its common name, this rhythm is not confined to the compact AV node but rather is re-entry occurring within the tissue surrounding the AV node. • For it to occur there must be critical differences in the conducting properties of two bundles of fibres that approach the AV node known as the ‘fast’ and ‘slow’ pathways. If these differences are present, re-entry can occur (see figure 4). • As the conducting properties of these pathways can change with age, a patient can develop the substrate for this arrhythmia at any age. Patients with this arrhythmia most commonly present in mid-life. • In these circumstances the ECG is usually normal. Intermittent first-degree AV block, or firstdegree AV block after an atrial ectopic can be a clue to the presence of the substrate for this arrhythmia. Atrioventricular re-entry • In this circumstance the patient is born with an accessory electrical pathway that allows an impulse to travel down the normal conducting system, then back up to the atria via the accessory pathway, initiating a loop of re-entry (orthodromic re-entry). This results in a narrow complex regular tachycardia (see figure 5A). • This can occur in the reverse direction also (antidromic re-entry), but in this circumstance the tachycardia has a broad complex because the ventricles are activated via an inefficient path and so take longer to depolarise (see figure 5B). • Patients often present in childhood and may have the resting ECG features of Wolff-ParkinsonWhite syndrome. The accessory pathway may however be ‘concealed’ and the ECG entirely normal. As symptoms usually occur infrequently, monitoring techniques are a waste of time (and money) in these conditions. Patients with symptoms suggestive of these arrhythmias may be referred for early electrophysiological studies, which can confirm the diagnosis. Ablation may then be offered for cure of these rhythms, at low risk to the patient. Alternatively the patient may opt for medical, or no treatment, if symptoms are infrequent. www.australiandoctor.com.au • Sulfi S, et al. Limited clinical utility of Holter monitoring in patients with palpitations or altered consciousness: analysis of 8973 recordings in 7394 patients. Annals of Noninvasive Electrocardiology 2008; 1:39-43. • Medi C, et al. Clinical update – atrial fibrillation. Medical Journal of Australia 2007; 186:197202. • Zimetbaum P, Josephson ME. Evaluation of palpitations. New England Journal of Medicine 1998; 338:1369-77. Online resources • Heart Rhythm Society, About patient education: www.hrsonline.org/Patient Info/ • Heart Rhythm Society, Patient education PDFs: www.hrsonline.org/Educat ion/Resources • HealthInsite, Arrhythmia: www.healthinsite.gov.au/to pics/Arrhythmia cont’d page 40 A D _ 0 4 0 _ _ _ MA R 1 3 _ 0 9 . p d f Pa ge 4 0 5 / 3 / 0 9 , 1 1 : 5 2 AM HOW TO TREAT Palpitations GP’s contribution DR ROSS WILSON Bathurst, NSW Case study Mr EB, 64, owns a small business selling batteries for cars and trucks. He has been under considerable stress because of both the global financial crisis and his wife recently developing metastatic breast cancer necessitating chemotherapy. He has no significant past medical history; his height is 180cm and weight 70kg. His presenting complaint is an irregular thumping in his chest and the feeling that he may faint when these episodes occur. He has not lost consciousness, still regularly walks 3-4km daily and despite his age, plays squash weekly. He has not experi- Ambulatory monitor results enced any of his palpitations while exercising. Physical examination is unremarkable. He is normotensive, with no stigma of thyroid disease and dual heart sounds. ECG shows sinus rhythm and is within normal limits. Haematology, done partly at his request, is normal. Thyroid function tests, cholesterol and triglycerides are normal. His Holter monitor report is shown at right. Questions for the author Should we further investigate Mr EB? Yes. Mr EB has recent onset of frequent ventricular ectopy with associated presyncope. Given his age alone, he has a 5-10% fiveyear risk of cardiovascular events. He should have a cardiac echo to assess his ventricular function and a stress test to assess for ischaemic heart disease. What role would beta blockade play in controlling his symptoms? Beta blockers are variably effective in suppressing ventricular ectopy and may cause side effects. A trial of beta blockade could be discussed with the patient if investigations are unremarkable. Will reassurance and stress management have any role or effect? Often a patient is very reassured if cardiac investigations are unremarkable, and can learn to ignore the ectopy. Although reduction of stress is often mentioned in the management of ventricular ectopy, there are no studies to demonstrate its benefit. How to Treat Quiz Duration of recording Resting ECG report Average heart rate (range) Rhythm during recording Patient-reported events Ventricular ectopy Supraventricular ectopy Bradycardia/pauses Tachycardia ST-segment changes Other Conclusions 23:43 hours Sinus rhythm, within normal limits 65bpm (range 48-93 bpm) Sinus rhythm Nil events reported by patient, although event button pushed eight times, with no arrhythmia at any time Moderately frequent uniform ventricular ectopy with no complex ventricular arrhythmias apart from a very occasional couplet. Ventricular ectopy persisted throughout the 24-hour period Occasional supraventricular ectopy with only one fourbeat run of SVT Nil Nil No significant ST-segment changes Nil Resting ECG shows sinus rhythm No patient-reported events Moderately frequent simple ventricular ectopy Occasional supraventricular ectopy with a single four-beat run of SVT of no clinical significance INSTRUCTIONS Complete this quiz online and fill in the GP evaluation form to earn 2 CPD or PDP points. We no longer accept quizzes by post or fax. The mark required to obtain points is 80%. Please note that some questions have more than one correct answer. Palpitations — 13 March 2009 1. Claire, 38, presents with palpitations on and off for a few months. She describes the sensation of her “heart skipping a beat”, followed by a “thump”. Claire mainly notices the palpitations when watching TV or lying in bed at night. She is otherwise well and takes no prescribed medications. Which TWO statements are correct? a) It is important to ask if Claire has felt lightheaded or faint with the palpitations b) It is not important to ask whether the palpitations occur with exercise c) Asking about a family history of heart disease is not important as it is unlikely to be of relevance d) It is important to enquire about any use of overthe-counter (OTC) medications and recreational drugs 2. The palpitations are occurring every day, which is making Claire anxious, but she does not feel unwell with them. They never occur when she is exercising. Her family history is unremarkable. Claire’s cardiovascular examination is normal. Which TWO statements are correct? a) Claire’s history is typical of benign ventricular ectopy and therefore no investigations are required b) Claire should have an ECG c) Claire should have baseline bloods including FBC, electrolytes, magnesium and thyroid function tests d) Claire should have a chest X-ray 3. Claire’s ECG shows sinus rhythm and is normal. She undergoes Holter monitoring, which demonstrates infrequent ventricular ectopics (<0.1% of beats) at rest. Which TWO statements are correct? ONLINE ONLY www.australiandoctor.com.au/cpd/ for immediate feedback a) Claire can be reassured that infrequent ventricular ectopics (<0.1% of beats) at rest in association with a normal clinical examination and ECG are considered benign b) Claire needs to have an echocardiogram to exclude structural heart disease c) Claire’s management should include identification and removal of any triggering factors such as caffeine or dehydration d) Claire should be started on an antiarrhythmic agent 4. Which TWO statements about re-entrant supraventricular tachycardia are correct? a) Re-entrant supraventricular tachycardia is of sudden onset and offset b) Re-entrant supraventricular tachycardia only occurs in patients with structurally abnormal hearts c) Cardiac event monitoring is the best method of diagnosing of re-entrant supraventricular tachycardia d) Ablation may be curative for re-entrant supraventricular tachycardia 5. Which TWO statements about atrioventricular re-entrant tachycardia are correct? a) Atrioventricular re-entrant tachycardia is the most common cause of re-entrant supraventricular tachycardia b) Atrioventricular re-entrant tachycardia always presents with a narrow complex tachycardia c) In atrioventricular re-entrant tachycardia the ECG may be entirely normal d) The ECG in atrioventricular re-entant tachycardia may have the resting features of Wolff-Parkinson-White syndrome 6. Which TWO statements about atrioventricular (AV) nodal re-entrant tachycardia are correct? a) Patients with atrioventricular nodal reentrant tachycardia are born with an accessory electrical pathway b) Patients with atrioventricular nodal reentrant tachycardia most commonly present in childhood c) In atrioventricular nodal re-entrant tachycardia the ECG is usually normal d) Intermittent first-degree AV block can be a clue to the presence of the substrate for atrioventricular nodal re-entrant tachycardia 7. Barbara, 67, presents with episodic palpitations. The episodes last up to an hour and have been 2-3 weeks apart. The palpitations start and stop suddenly and can occur at any time. She describes them as fast and irregular, and feels uncomfortable with them, but not faint. Barbara has hypertension and type 2 diabetes, but is otherwise well. She takes an ACE inhibitor and metformin. Her BP is 145/90mmHg but cardiovascular examination is otherwise normal. An ECG shows sinus rhythm and meets the criteria for left ventricular hypertrophy. Which TWO statements are correct? a) Barbara’s history is suggestive of sinus tachycardia as a likely cause of her palpitations b) Barbara should have baseline blood tests for palpitations including FBC, electrolytes, magnesium and thyroid function tests c) In addition to the usual baseline blood tests, Barbara should have an assessment of her lipids and diabetes control d) A 24-hour Holter monitor would be the best method of cardiac monitoring for Barbara 8. Barbara is found to have paroxysmal atrial fibrillation. An echocardiogram shows a normal left ventricular ejection fraction and no significant valvular disease. What is her CHADS2 score? a) 0 b) 1 c) 2 d) 3 9. Barbara does not have any serious contraindications to anticoagulation. Based on her CHADS2 score, what would be the recommendation regarding anticoagulation therapy? a) Anticoagulation therapy would not be recommended b) Aspirin at a dose of 81-325mg/day c) Warfarin with a target INR of 1.5-2.0 d) Warfarin with a target INR of 2.0-3.0 10. Which THREE statements regarding some common findings on Holter monitoring are correct? a) Rare atrial ectopics (<0.1% of beats) are a common normal finding b) All patients with atrial ectopy that is more frequent (>0.1% of beats) require treatment c) Brief (<1 minute) supraventricular tachycardia episodes are a common normal finding and if infrequent do not require specific treatment d) Frequent episodes of brief (<1 minute) supraventricular tachycardia can indicate a propensity to longer episodes of atrial arrhythmias at other times CPD QUIZ UPDATE The RACGP now requires that a brief GP evaluation form be completed with every quiz to obtain category 2 CPD or PDP points for the 2008-10 triennium. You can complete this online along with the quiz at www.australiandoctor.com.au. Because this is a requirement, we are no longer able to accept the quiz by post or fax. However, we have included the quiz questions here for those who like to prepare the answers before completing the quiz online. HOW TO TREAT Editor: Dr Wendy Morgan Co-ordinator: Julian McAllan Quiz: Dr Wendy Morgan NEXT WEEK Chronic pelvic pain can be a symptom of many different conditions of the GI, urological and genital tracts. Nearly three times as many women as men experience chronic pelvic pain. Understanding the dynamic relationship of the organs in the pelvic area in treating chronic pelvic pain in women is the subject of next week’s How to Treat. The author is Dr Jason Abbott, senior lecturer in obstetrics and gyaecology, University of New South Wales, Sydney, and the school of women’s and children’s health, Royal Hospital for Women, Randwick, NSW. 40 | Australian Doctor | 13 March 2009 www.australiandoctor.com.au