Cardiac Crisk in the Young

CRY Cardiac Risk in the Young.




Medical Information

Hypertrophic Cardiomyopathy (HCM)
Arrhythmogenic Right Ventricular Cardiomyopathy ARVC)
Dilated Cardiomyopathy (DCM)
Myocarditis
Coronary Artery Disease (CAD)
Ion Channelopathies (Long QT, Brugada, Lev-Lenegre's....)
Wolff (Wolfe) Parkinson White Syndrome (WPW)
Coronary Artery Anomalies (CAAs)
Marfan Syndrome
Restrictive Cardiomyopathy (RCM)
Other Cardiac Conditions -
Endocardial Fibroelastosis (EFE), Tachycardia
Long QT Syndrome, Brugada & Ion Channelopathies



The Ion Channelopathies are rare disorders of the DNA code (known as "mutations") in specific genes that can cause sudden death due to heart rhythm disturbances. The genes in question produce proteins that are found mainly on the outside of cells and regulate electrical activity. They are therefore, not detectable at the time of post mortem.

The proteins involved in the Long QT Syndrome consist of two of the potassium "channels" which regulate the behaviour of potassium ions moving from the inside to the outside of the cell. In addition, a sodium "channel" is also affected and this regulates the behaviour of sodium ions that move from the outside to the inside of cells. The same sodium channel protein has also been found to have mutations in the Brugada Syndrome, Lev-Lenegre’s Syndrome and Idiopathic Ventricular Fibrillation without Brugada ECG changes.

Catecholaminergic Polymorphic VT has been associated very recently with another protein (hRyR2) that is found inside the cell and regulates the release of calcium ions into the rest of the cell.

Long QT Syndrome
In this condition the potassium channels do not behave as efficiently as normal or the sodium channel over-activates. This results in an electrical disturbance in the cell called prolonged repolarisation. This can be reflected on the ECG as lengthening of the time period known as the "QT interval", hence the name, Long QT Syndrome. This is also known as the Romano Ward Syndrome (the commonest form) and Jervell Lange-Neilsen Syndrome (a rare form associated with deafness).

Symptoms

Blackouts are the most common problem, although sometimes palpitations can be problematic. The other main effect of the condition is sudden death. There is however, a wide spectrum of severity and these vary according to the type of gene involved, ***, age and length of the QT interval.

The potassium channel Long QT syndrome is associated with sudden death related to exercise or when startled or aroused suddenly, while the sodium channel form is associated with death while asleep.

Signs

There are no physical signs of the condition.

Diagnosis

This involves observation of the ECG for the lengthening of the QT interval and abnormality of other parts of the ECG that represent repolarisation. These are the T Waves. Unfortunately, the wide spectrum of the condition means that many individuals might be carriers but not exhibit any ECG changes. It may require repeated ECGs, exercise tests and 24-48 hour tape monitoring to see any hint of the condition. There does not appear to be much role for more aggressive tests such as electro-physiological studies. Future diagnosis might be improved however, by genetic testing. Unfortunately, this is limited, because only 50% of known Long QT patients have mutations of the previously mentioned genes. There is an additional problem in that families with identified mutations appear to have a specific change to the DNA code, which is not found in other families (known as a "private" mutation).

This is further complicated because each individual carrier of the same mutation may be affected with differing severity, even if they are from the same family. This makes decisions on management of the condition very difficult.

Management

If it is decided that the risk to an individual is great enough that treatment is required, then drugs are invariably used. The commonest drug is a beta-blocker. This blocks the affects of adrenaline and associated natural chemicals in the body that have an action on the heart. This does appear to be successful in reducing the risk of sudden death. There are other more recent trends in drug treatment that have yet to be clarified that appear promising. These involve using specific classes of drugs that block disturbances in the heart rhythm that cause sudden death (known as antiarrhythmics).

If the risk is felt to be great enough, special devices may be used in addition to medication. Pacemakers that control the heart rate have been used successfully, as have cardiac defibrillators (ICDs). These are similar to Pacemakers, except they are also able to shock the heart when a rhythm disturbance occurs that might be life threatening. In addition to these measures, we do advise patients with Long QT Syndrome to avoid excessive exercise or strenuous athletic activities.

Drugs to avoid

Top of the page

Brugada Syndrome
This condition was first identified and then further clarified from the late 1980’s onwards. It is a rare condition in the western world that appears to be considerably more common amongst young men in South East Asia. It is also known as "Sudden Unexpected Death Syndrome" (SUDS). It has very recently been associated with mutations in the sodium channel, but this appears to only account for 20% of sufferers. The sodium channel behaves abnormally in that movement of sodium ions into the cells is restricted. This results in changes on the ECG, but no abnormalities in the structure of the heart. These changes have been described as follows "right bundle branch block with J point elevation and concave ST elevation".

Symptoms

Blackouts, palpitations and sudden death.

Signs

There are no physical signs associated.

Diagnosis

This is again, on the basis of the ECG appearance, which may be present or absent. If it is absent then there are tests that can bring it out. These are known as provocation tests that use short injections of drugs that are "anti-arrhythmic", i.e. attempt to control the hearts’ rhythm. There is some controversy now as to how reassuring a negative result is. The role for electro-physiological testing is still awaited.

Because of the small proportion of sufferers have been identified with these mutations, genetic testing is limited in it’s application.

Management

The condition can carry a poor prognosis, particularly in those who are symptomatic, i.e. at least a 10% death rate per year. It is therefore standard practice at present to use an ICD to protect most patients. Drug therapy has not appeared to be successful but there may be a role for electro-physiological studies to differentiate those people who do or do not require an ICD.

Top of the page

Lev-Lenegre’s Syndrome

This is another very rare condition where the hearts’ conduction of electrical impulses is affected. This results in the gradual development over time of heart block that may result in death due to the cessation of the heart rhythm i.e. asystole, or escape rapid rhythm disturbances, i.e. ventricular arrhythmias. Only certain cases have had sodium channel mutations associated with them, so again genetic testing’s usage is limited.

Symptoms

Blackouts and dizziness are the usual symptoms and the findings may be detected on ECG or 24-48 hour Holter monitoring. Electro-physiological study may also assist in diagnosis.

Management

The successful treatment appears to be permanent pacemakers, which stop the heart slowing excessively, although this may not prevent the ventricular arrhythmias. Therefore, addition medical treatment with tablets may be appropriate or even an ICD

Top of the page

Idiopathic Ventricular Fibrillation
There has been one report of patients with this condition, which is similar to Brugada, but without the associated ECG changes, who also had sodium channel mutations. The treatment again revolves around the use of ICDs.

Top of the page

Catecholaminergic Polymorphic VT

In early 2001, two research groups reported mutations in the hRyR2 protein mentioned above. This is a rare condition found in young people who can black out or die suddenly when exerting themselves.

The diagnosis only appears to be easily made when these rhythm disturbances have been recorded and recognised. The sufferers respond dramatically to beta-blockers and a restriction of exercise, and have a much better outlook on treatment.

Variable presentation of Brugada syndrome: lessons from three generations with syncope

Adrian Plunkett, senior house officer1, J A Hulse, consultant paediatrician1, B Mishra, consultant cardiologist2, J Gill, consultant cardiologist3
1 Department of Paediatrics, Maidstone Hospital, Maidstone ME16 9QQ, 2 Department of Cardiology, Maidstone Hospital, 3 Department of Cardiology, St Thomas's Hospital, London SE1 7EH


Correspondence to: A Plunkett adrianplunkett@doctors.org.uk





General practitioners see many patients with syncope but in only a few cases is this due to a primary cardiac arrhythmia. Nevertheless, identifying such patients is important because some familial arrhythmias are associated with a risk of sudden death. We describe how a recently defined arrhythmia, Brugada syndrome, caused syncope in three generations of one family. The cases show the importance of taking an adequate family history when assessing patients with syncope and how this information is crucial to diagnosis and management.

Brugada syndrome is an inherited cardiac disease causing ventricular tachyarrhythmias in patients with structurally normal hearts.1 Since its first description in 1992, the number of cases reported worldwide has grown substantially, and it is thought to account for many cases of unexpected sudden death.

The syndrome is characterised by a history of syncope or cardiac arrest and a characteristic electrocardiographic pattern: right bundle branch block and ST segment elevation in V1 to V3. Most cases are inherited as an autosomal dominant trait, explaining a strong family history of syncope or sudden death.2 Some patients have normal resting electrocardiographic appearances but the classic changes can be induced by giving ajmaline, an antiarrhythmic drug.3


Case 1

A 27 year old woman presented with three episodes of sudden loss of consciousness over six weeks. She had no palpitations and no consistent precipitants. On each occasion she was unconscious for a few seconds before regaining consciousness. She had had similar episodes when she was 7 years old. These had been investigated by a neurologist, but no diagnosis had been made. In the intervening years she had been symptom free.

Examination showed no abnormality, but her resting electrocardiogram showed partial right bundle branch block (fig 1). Twenty four hour cardiac monitoring and echocardiography gave normal results. However, a patient activated electrocardiograph showed ventricular tachycardia during a symptomatic spell. An electrophysiological study showed ventricular tachycardia during ventricular stimulation. She had magnetic resonance imaging of the heart to rule out right ventricular dysplasia, and this showed no abnormality.

Fig 1 Resting electrocardiogram of case 1 showing partial right bundle branch block with normal precordial ST segments





In view of the electrocardiogram and the recurrent ventricular tachycardia, in a structurally normal heart, a diagnosis of Brugada syndrome was made. A cardioverter defibrillator was implanted to prevent any life threatening arrhythmias. Since then she has remained well.


Case 2


The mother of case 1, a 49 year old woman, had had idiopathic epilepsy diagnosed for many years. Since the age of 7 years she had had episodes of dizziness and loss of consciousness. The episodes were variable in nature and occasionally associated with chest pain, sweating, and fitting activity, such as rigidity and shaking of the limbs.

After her daughter had Brugada syndrome diagnosed, she was referred to the cardiologist who had been looking after her daughter. Her resting electrocardiogram appeared normal, but an ajmaline test provoked changes consistent with Brugada syndrome (fig 2). She had a cardioverter defibrillator inserted and has since been free of symptoms.


Fig 2 Electrocardiograms from case 2, taken while resting (top) and after being given ajmaline (bottom). Note ST segment elevation in V1-V3 after ajmaline

Case 3


The woman in case 1 had an 8 year old son with Down's syndrome. Trisomy 21 (47 XY,+21) with partial atrioventricular septal defect was diagnosed after birth. He had corrective surgery for the atrioventricular septal defect at 3 years of age. Before this surgery he had collapsed several times in what were thought to be drop attacks. The attacks resolved after the cardiac surgery.

He presented to hospital aged 6 years after an episode of collapse associated with cyanosis and unconsciousness. His electrocardiogram showed partial right bundle branch block, which was attributed to his previous cardiac surgery. Results of 24 hour cardiac monitoring and electroencephalography were normal.

He continued to have dizzy spells and collapses, culminating in a severe episode at school, three months after his mother had Brugada syndrome diagnosed. The episode was witnessed by his teacher, who reported that his pulse rate was extremely rapid during the attack. Subsequent investigations confirmed that he had Brugada syndrome, and he has remained free of symptoms since the insertion of a cardioverter defibrillator.


Case 3

The family history of patients with syncope should be carefully evaluated for evidence of familial causes of sudden cardiac death. The commonest of these is hypertrophic cardiomyopathy, which has an estimated prevalence of 1:500 to 1:5000.4 Other causes include hereditary arrhythmias (such as long QT syndromes and Brugada syndrome) and hereditary structural defects (such as arrhythmogenic right ventricular dysplasia). These conditions are rare compared with other causes of syncope. Careful history taking and simple investigations are therefore needed to identify patients who warrant referral for specialist assessment.

Diagnosing Brugada syndrome is not straight-forward as it exists in many forms. The syndrome is inherited as an autosomal dominant trait, but expression varies—for example, the typical electrocardiographic pattern is often absent or transitory.5 The syndrome is most common in men of South East Asian origin, but it has been described in many different age groups and ethnic origins.5

Our report shows the difficulty in diagnosing Brugada syndrome in atypical cases. Case 2 had symptoms but normal resting electrocardiographic appearances. Diagnosis in such patients depends on unmasking concealed conduction abnormalities by giving intravenous antiarrhythmic drugs such as ajmaline. This test is useful because symptomatic patients are at risk of sudden death if left untreated.6

Case 2 also illustrates the difficulty in distinguishing cardiac causes of loss of consciousness from neurological causes. Investigations in all cases of unexplained syncope should include resting and 24 hour electrocardiography. However, normal results do not exclude Brugada syndrome, and if the patient is at risk an ajmaline test should be considered.

Diagnosis is further complicated by unrelated conditions such as right ventricular dysplasia, in which the electrocardiogram may show the typical Brugada-like pattern and the patient is prone to sudden arrhythmic death.7 Structural heart disease must therefore be excluded before diagnosing Brugada syndrome.

Identification of a genetic abnormality is helpful in distinguishing Brugada syndrome. Furthermore, identification of a recognised mutation will facilitate screening of relatives. The genetic defect is a mutated cardiac sodium channel gene (SCN5A) on chromosome 3.8 The mutant sodium channel shortens the cardiac action potential, making parts of the cardiac tissue vulnerable to re-entry circuits. There are several recognised mutations causing Brugada syndrome, but in many cases a recognised mutation is not found. Such genetic heterogeneity may explain the heterogeneity of expression between individuals.

The prognosis for patients with Brugada syndrome is poor unless they are treated. Mortality is thought to be up to 10% a year.5 Drug treatment is not effective, but an implantable cardioverter defibrillator has been shown to prevent sudden death.3




--------------------------------------------------------------------------------
A family history should be taken in all patients with unexplained syncope
Contributors: AP wrote the paper. JAH and BM supervised and revised the paper. JG contributed to the diagnosis and management of the cases. JAH is the guarantor.

Competing interests: None declared.


Brugada P, Brugada J. Right bundle branch block, persistent ST segment elevation and sudden cardiac death: a distinct clinical and electrocardiographic syndrome. J Am Coll Cardiol 1992;20: 1391-6.[ISI][Medline]
Corrado D, Buja, G, Basso C, Nava A, Thiene G. What is the Brugada syndrome? Cardiol Rev 1999;7: 191-5.[Medline]
Brugada P, Brugada R, Brugada J. The Brugada syndrome. Curr Cardiol Rep 2000;2: 507-14.[Medline]
Codd MB, Sugrue DD, Gersh BJ, Melton LJ. Epidemiology of idiopathic dilated and hypertrophic cardiomyopathy. Circulation 1989;80: 564.[Abstract]
Naccarelli GV, Antzelevitch C. The Brugada syndrome: clinical, genetic, cellular, and molecular abnormalities. Am J Med 2001;110: 573-81.[CrossRef][ISI][Medline]
Brugada J, Brugada R, Brugada P. Right bundle branch block and ST-segment elevation in leads V1 through V3. A marker for sudden death in patients without demonstrable structural heart disease. Circulation 1998;97: 457-60.[Abstract/Free Full Text]
Izumi T, Ajiki K, Nozaki A, Takahashi S, Tabei F, Hayakawa H, Sugimoto T. Right ventricular cardiomyopathy showing right bundle branch block and right precordial ST segment elevation. Intern Med 2000;39: 28-33.[ISI][Medline]
Towbin JA. Cardiac arrhythmias: the genetic connection. J Cardiovasc Electrophysiol 2000;11: 601-2.[ISI][Medline]

BMJ 1999;319:1092 ( 23 October )

News
MRI found suitable for detecting coronary heart disease Deborah Josefson , San Francisco

Traditional electrocardiographic exercise stress tests for heart disease may soon be supplanted by cardiac magnetic resonance imaging (MRI).

Researchers from Wake Forest University School of Medicine in Winston Salem, North Carolina, investigated the technique of fast cinematic, cardiac magnetic resonance imaging to detect ischaemic heart disease in patients unsuitable for the usual stress echocardiography (Circulation 1999;100:1676-9, 1697-702).

Classically, patients with suspected coronary artery disease are referred for exercise stress testing and are hooked up to electrocardiographic and blood pressure monitors while doing progressively more intensive exercise on a treadmill.

Treadmill based stress tests are not suitable for many people, such as some postoperative patients, frail elderly people, amputees, and many patients who are obese or have chronic lung diseases that limit their exercise capacity.

To accommodate this problem, pharmacological stress tests were introduced to mimic the effect of exercise on the heart. Stress tests using the drugsdobutamine, dipyridamole, or adenosinecoupled with either echocardiographic or radionuclide based imaging of the heart are usually performed.

The drugs are used to induce vasodilation and tachycardia, simulating exercise. Echocardiography is then done to assess the effect of these vasodilatory drugs on left ventricular contractility. Wall motion abnormalities induced by these drugs may signify underlying coronary artery disease.

Alternatively, radionuclide perfusion scans which measure the uptake of various radioactive substances by the heart are also performed in this population.

Unfortunately, both tests have serious limitations, which may make them unsuitable for the very population for which they were intended. Because echocardiography relies on transmission of sound waves and their reflection back to produce an image, patients who are obese, have chronic lung conditions (such as emphysema), or have had cardiothoracic surgery will have suboptimal stress echo results with poor image quality.

To circumvent these problems, Dr Gregory Hundley and colleagues from Wake Forest University investigated fast cinematic cardiac magnetic resonance imaging as a technique for dobutamine based stress tests. A total of 163 patients ranging in age from 30 to 88 years were selected for the tests. Ten patients were removed from the study, six because they could not fit into the machine and four because of anxiety.

Of the remaining 153 patients, 139 underwent the full testing. The test lasted an average of 144 minutes, including preparation and recovery time; time in the scanner itself averaged 53 minutes.

All patients had previously undergone traditional dobutamine stress echocardiography, but had suboptimal images, despite the use of an advanced techniquesecond harmonic imagingto improve resolution.

Most of the patients tested were obese, with 41%of patients above 150%of their ideal body weight and 80%above 120%of ideal weight. Thirty two per cent of the patients had had a coronary artery bypass graft, and 21%had chronic obstructive lung disease.

Thirty six of the 139 patients had evidence of ischaemia induced by dobutamine; 103 lacked it. Forty one of the study subjects underwent coronary angiography within five weeks of the imaging stress test.

As measured against this gold standard, fast cinematic magnetic resonance imaging was 82%sensitive in detecting 70%or greater stenosis in a single coronary artery and 88%sensitive in detecting that degree of stenosis in two vessels. It was 100%accurate in diagnosing left main coronary artery disease as well as occlusion in three vessels.

The authors concluded that "MRI can be used to assess contractility continuously during a stress test and to detect inducible ischemia in patients poorly suited for stress echocardiograms."

PREHOSPITAL CARE

The ABC of community emergency care
3 Chest pain C Laird1, P Driscoll2 and J Wardrope3
1 BASICS Scotland, Auchterarder, UK
2 Accident and Emergency Department, Hope Hospital, Salford, UK
3 Accident and Emergency Department, Northern General Hospital, Sheffield, UK


Correspondence to:
Mr C Laird
BASICS Scotland, Collyhill Lodge, Auchterarder PH3 1ED, UK; claird@basics-scotland.org.uk


Keywords: chest pain

Chest pain is the commonest reason for 999 calls and accounts for 2.5% of out of hours calls. Of patients taken to hospital about 10% will have an acute myocardial infarction (AMI). Evidence suggests that up to 7.5% of these will be missed on first presentation. There are a number of other life threatening conditions, which can present as chest pain and must not be overlooked. The objectives of this article are therefore to provide a safe and comprehensive system of dealing with this presenting complaint (box 1).


Box 1 Objectives of assessment of patients with chest pain

To undertake a primary survey of the patient and treat any immediately life threatening problems

To identify any patients who have a normal primary survey but have an obvious need for hospital admission

To undertake a secondary survey considering other systems of the body where dysfunction could present as chest pain

To consider a list of differential diagnoses

Discuss treatment based on the probable diagnosis(es) and whether home management or hospital admission is appropriate

Consider follow up if not admitted







PRIMARY SURVEY
ABC principles


Primary survey—If any of the following present treat immediately and transfer to hospital

Airway obstruction

Respiratory rate <10 or >29 per minute

O2 sats <93%

Pulse <50 or >120

Systolic BP <90 mm Hg

Glasgow coma score <12







PATIENTS WITH NORMAL PRIMARY SURVEY WITH OBVIOUS NEED FOR HOSPITAL ADMISSION
There are four life threatening medical conditions that can present with chest pain. These are:


Acute coronary syndrome (ACS)

Massive pulmonary embolus

Dissection of the thoracic aorta

Tension pneumothorax

The history and a brief examination may lead you to suspect that one of these is the probable diagnosis but often in the early stages, patients may not have significant abnormal physical signs. Nevertheless, urgent hospital admission must be arranged if you suspect any of the above or any other life threatening diagnosis.

In the case of myocardial infarction it should be remembered that 50% of sudden cardiac deaths occur within one hour of the start of a myocardial infarction and 75% within three hours. In addition, the benefits of thrombolysis are directly related to the length of time between the onset of symptoms and its delivery. For both these reasons it is important that if you suspect a myocardial infarction you have immediate access to a defibrillator and can deliver thrombolysis or arrange rapid transportation to a facility where it can be delivered.





View larger version (108K):
[in this window]
[in a new window]
Figure 1 Defibrillator.





SECONDARY SURVEY (INCLUDING HISTORY TAKING)
Having dealt with the potential life threatening cases you will be left with a group of patients with whom a more thorough clinical examination will be required before considering whether they can be either treated and left at home, or referred elsewhere.
Take a history of the presenting complaint, gather relevant information, and perform an examination (see article 2 in this series and journal web site (http://www.emjonline.com/supplemental) on examination).

For patients with chest pain—respiratory, cardiovascular, abdominal, and musculoskeletal examinations are appropriate.





View larger version (130K):
[in this window]
[in a new window]
Figure 2 Patient with chest pain.




The following points may be helpful in reaching a diagnosis in a patient presenting with chest pain.
Type of pain
There are three main categories of chest pain that patients present with. These are:


Typical cardiac pain

Pleuritic chest pain

Atypical chest pain

To differentiate these types of pain it is important to differentiate the two broad categories of pain of which patients will complain. These are somatic and visceral. Somatic pain originates from the chest wall (skin, ribs, and intercostal muscles), pericardium (fibrous and parietal layer), and the parietal pleura. Pain from these structures is transmitted to the brain by the somatic nerve fibres that enable the brain to accurately locate the site of the problem. This means the patient may be able to accurately locate the area of pain. In the case of pleuritic chest pain, it will also be specifically related to movements of breathing. Consequently if the patient is asked to take a deep breath they will experience more pain. Visceral pain in contrast originates from the deeper thoracic structures (heart, blood vessels, and oesophagus) and is carried in the autonomic nerve fibres. These give a less precise location of the pain, and the pain is generally described as a discomfort, heaviness, or ache.


Always ask about the relation of the pain to breathing, movement, exercise, and rest.




Progress of symptoms
Gain a detailed impression of how the pain started. Pain that has wakened the patient should be regarded as significant.

Duration of pain
Typical cardiac pain that lasts less than 15 minutes is defined as angina. Acute coronary syndrome pain lasts more than 15 minutes but it would be unusual for it to continue for over 24 hours. Chest pain lasting only a few seconds is unlikely to be cardiac.

Associated symptoms
Inquire if the patient has nausea, vomiting, shortness of breath, sweating, cough, and sputum production. Have they had any leg swelling, injury, or recent surgery?

Previous similar symptoms
A previous history of ischemic heart disease makes it much more probable that the pain is cardiac. However, patients with heart disease do have other chest problems and the patient may say that the pain is different from their usual symptoms.

Risk factors
The presence of risk factors for cardiovascular disease should increase your suspicion as to a cardiac cause for the pain (box 2).


Box 2 Important risk factors for angina or acute coronary syndrome

Smoking

Hypertension

Diabetes

Strong family history (that is, ischaemic heart disease onset <60 years)

High cholesterol concentrations






Medical history/drugs allergies
(See article 2 of the series on examination.)

It is important during the history taking to ask the patient about their medical history as they may already have had an illness that could present as chest pain A drug history is also important, specifically ask about aspirin (you may need to give this), and if they have taken GTN, warfarin, or other cardiac medications.

Social history and substances
(See article 2 of the series on examination.)

Some illegal drugs such as cocaine may cause chest pain. Patients with a history of alcohol misuse or illegal drug use are at increased risk of developing chest infections and suffering from thromboembolic disease.

Examination
(See article 2 of this series on examination.)

Vital signs
Unless you are transporting the patient immediately, always measure a full set of vital signs.

General
Is the patient confused/anxious, short of breath? This indicates a critical situation. Go back to primary survey.

Is the patient obviously in pain? Are they pale/sweaty? Have they been sick? If the answer to any of these questions is positive, there is a greater likelihood of serious disease.

Cardiovascular
Pay special attention to the rate and rhythm of the arterial pulse and the level of the jugular venous pulse. Ask the patient to take a deep breath, look for an increase in pain during inspiration. Follow this by listening to the heart sounds and the lung bases. Finish by examining the ankles, calves, and foot pulses (for oedema/signs of DVT).

Chest wall tenderness reproducing the patient’s pain is suggestive of musculoskeletal pain but studies have shown this sign to be present in up to 15% of patients with confirmed myocardial infarction. Therefore this sign on its own should never be used to exclude a myocardial infarction.

Tests
An ECG is indicated in patients with chest pain. Under the age of 30, ischaemic heart disease is uncommon but if the pain is typical, obtain a 12 lead ECG. Detailed interpretation of the ECG is beyond the scope of this text but readers are referred to the texts in the further reading section at the end of this article. An abnormal ECG in a patient with chest pain is an indication for admission to hospital.


DIFFERENTIAL DIAGNOSIS
Table 1 shows a list of the differential diagnoses classified by the type of pain they present with.
DIFFERENTIAL DIAGNOSIS



View this table:
[in this window]
[in a new window]
Table 1 Differential diagnoses



Cardiac pain
Pain arising from the heart may present as either "typical cardiac pain" or "atypical chest pain". The former is described as a central heavy or crushing pain that may radiate to the jaw, neck, shoulder, or arm.
Ischaemic cardiac pain originates from the myocardium when its blood supply is insufficient for its needs. It can be broadly divided into two categories—angina and acute coronary syndrome.

On a clinical basis, angina is arbitrarily defined as lasting less than 15 minutes. It is often related to increased myocardial oxygen demand, for example, stress or exercise. All ischaemic cardiac pain lasting more than 15 minutes, or less than 15 minutes but recurring on a regular basis, is classified as acute coronary syndrome. This includes a variety of conditions including:


Infarction with ST elevation (STEMI)—usually progresses to Q wave MI (QMI)

MI confirmed but no Q developed (NQMI)—usually no ST elevation either (NSTEMI)

MI occurring with left bundle branch block (LBBB) hiding ST elevation

ACS without serological evidence of MI = unstable angina

Angina is caused by a narrow coronary artery, which at times of increased myocardial oxygen demand cannot supply sufficient blood to the muscle. Unstable angina and NQMI are normally associated with a thrombus partially occluding a coronary artery. These thrombi are unstable and can break off leading to myocardial ischaemia and infarction. ST elevation myocardial infarction (STMI) is caused by a thrombus completely occluding a coronary artery.

Features of ischaemic cardiac pain

Features of ischaemic cardiac pain

Precipitated by exertion

Radiation of pain to jaw, neck, shoulder, or arm

Relieved by GTN

Previous history of similar pain relieved by rest or GTN

History of ischaemic heart disease

Age (unusual less than 35 years but not impossible)

Risk factors—a history of smoking, hypercholesterolaemia, hypertension, diabetes mellitus, or a family history of ischaemic heart disease in relatives under 60 years







TREATMENT
Angina
Consider this diagnosis if the pain lasted less than 15 minutes or settles within five minutes of GTN administration and is a single episode. If pain is recurrent, consider it to be acute coronary syndrome and refer. If the patient is young (35–70) and this is the first episode of typical ischaemic pain and has come on at rest, refer even with one episode.

Myocardial infarction
Initial/general—carry out a full ABC assessment and provide oxygen and analgesia (appropriate to the diagnosis). A defibrillator must be taken to any patient complaining of chest pain.


JRCALC MI management

Administer 400 µg GTN where systolic BP is estimated >90 mm Hg

Give high flow oxygen via a non-rebreathing mask

Where appropriate move to the ambulance at this stage

If pain persists consider a second dose of 400 µg GTN where systolic BP is estimated >90 mm Hg

Give aspirin 300 mg orally

Obtain intravenous access if not already achieved

Monitor BP for hypotension and position patient appropriately

If pain continues, morphine 2.5 mg–10 mg intravenously may be administered (nalbuphine 10–40 mg may be given as an alternative)

Pain assessment scoring should be carried out before and after analgesia has been administered

Remove to nearest suitable receiving hospital without delay for urgent thrombolytic therapy







Empowerment
If trained in thrombolysis then


Ensure the patient has the indications (typical chest pain+appropriate ST elevation; LBBB)

Ensure the patient has no contraindications

Explain risks and benefits

Obtain consent and administer thrombolysis






Who can be left at home?
Consider this option if the patient has a history of angina, and they have had a typical episode lasting less than 15 minutes, they are well and the ECG is normal. They must of course be told to call for assistance if the pain recurs. It is desirable to have a relative or carer stay with them, or to do a check by visit or telephone in a few hours.

Pericarditis
The pericardium is a double layer of tissue, which envelops the heart (fig 3). It has an outer thick, fibrous layer that is attached to the base of the great vessels and the diaphragm. The gap between the heart and this fibrous layer is called the pericardial space. This is covered by a thin, serous layer, which lines the inner surface of the fibrous pericardium as well as the outer surface of the heart. Normally the two serous layers slide over one another during the movement of the heart, an action facilitated by the small amount of fluid in pericardial space. However, in pericarditis the surfaces become swollen, tender, and inflamed. This usually results from infection but it can result from autoimmune reactions, after myocardial infarction and cardiac surgery.





View larger version (117K):
[in this window]
[in a new window]
Figure 3 Diagram of the pericardium.




Pericarditis commonly presents as chest pain described as midline and sharp. The pain is made worse by movement and breathing whereas sitting up and leaning forward may relieve it. The pain my radiate to the back, neck, or left shoulder and is associated with dyspnoea, tiredness, and fever.
Dissecting aortic aneurysm
In this condition blood breaks through the inner lining of the aorta and creates a false passage between the endothelium and the outer wall. In doing so it may occlude the branches of the aorta and give rise to a variety of conditions including stokes. It may also track proximally and burst through into the pericardium or damage the aortic valve. One of the signs of this can be disparity between the upper limb blood pressure recordings.

Typically the patient presents with severe, "ripping/sharp" chest pain radiating through to the back. Diagnosis is difficult but is made easier by thinking of the condition, particularly in those with a higher risk (for example, hypertension or Marfan’s syndrome). Examination may reveal a difference in the blood pressure between the left and right arm. There may be murmurs heard over the back (fig 4).





View larger version (130K):
[in this window]
[in a new window]
Figure 4 Dissecting aortic aneurysm.




Patients with ACS, pericarditis, or thoracic aortic dissection will usually have had problems identified in the primary survey. If not, correct any ABC abnormality, give pain relief and arrange immediate admission to hospital.
Cervical root pain
This occurs when one of the nerves that exits the cervical spine is irritated by a structures within the vertebral column.

The pain is limited to the upper chest and the neck and is usually precipitated by neck movement.

These patients will not normally require admission. Treatment will be from the following options: analgesia, non-steroidal anti-inflammatory drugs, muscle relaxants, and a soft cervical collar.

Chest wall pain
This is pain originating from the ribs or chest wall musculature, or both. It may be related to trauma in which case the area of tenderness is at the site of injury. In non-trauma cases, the pain and tenderness are usually over the anterior chest wall.

Treatment is with non-steroidal anti-inflammatory drugs.

If associated with major trauma, patients should be admitted.

Pneumothorax
A pneumothorax is the complete or partial collapse of a lung.

There is usually a sudden onset of sharp chest pain and dyspnoea. The pain is normally one sided and may radiate to the back. Risk factors include obstructive pulmonary disease, trauma, and tall thin young people.

Treat any ABC abnormality and provide oxygen and analgesia. This patient will need to be sent to hospital.

Pulmonary embolism
This occurs when a clot forms within the venous system of the body and then travels to the lungs and obstructs part of the pulmonary circulation (fig 5). The onset of symptoms is sudden, often unilateral and associated with dyspnoea and tachypnoea (respiratory rate >20).





View larger version (77K):
[in this window]
[in a new window]
Figure 5 Deep venous thrombosis.




Risk factors include a recent history of trauma or surgery, venous stasis, or hypercoagulability. The pre-test probability of a pulmonary embolism can be predicted from the table 2.



View this table:
[in this window]
[in a new window]
Table 2 Pre-test probability of pulmonary embolism Well’s criteria



The vital signs may be abnormal and hence the patient will be primary survey positive. If this is not the case, but pulmonary embolism is suspected, appropriate resuscitation should be started, if required, and the patient sent to hospital.
Infection
The patient may have a history of a current or recent upper respiratory tract infection and a productive cough. On examination there may also be fever and breathlessness.

To make decisions on treatment and whether the patient can be left at home, the following guidelines from The British Thoracic Society should be used:

Admit if:-

Children


Oxygen saturation <92%

Respiratory rate >50 breath/min, under 1 year 70 breath/min

Difficulty in breathing

Grunting

Signs of dehydration

Family not able to provide appropriate observation and supervision

Unable to take antibiotics because of vomiting

Adults


Confused

Oxygen saturation <92%

Respiratory rate >30 breath/min

Low blood pressure (systolic <90 mm Hg, diastolic < 60 mm Hg)

>50 years of age or have coexisting disease

Unable to take antibiotics because of vomiting

Treatment
If admission is not planned encourage the patient to rest, drink plenty of fluids, and not to smoke. Pleuritic pain should be treated with simple analgesics.

Amoxicillin is the antibiotic of choice for adults with erythromycin or clarithromycin as an alternative for patients who are hypersensitive to penicillins.

All children under 1 year should be examined by a doctor.

Amoxycillin is the first choice of antibiotic for children under 5. Alternatives are co-amoxiclav, cefaclor, erythromycin, clarithromycin, and azithromycin.

In children over 5, erythromycin or clarithromycin may be used as a first line treatment as mycoplasma pneumonia is more prevalent in this older age group.

Arrange review within 24 to 48 hours.

Oesophageal pain
This pain is caused by acid reflux from the stomach burning the oesophageal mucosa.

The pain may be of variable onset relieved by antacids, burning in nature, radiate to between the shoulder blades, and be accompanied by swallowing difficulties. Pain may be related to eating.

Treatment is with antacids, H2 antagonists, or proton pump inhibitors. If it does not respond to treatment, or swallowing difficulties develop, the patient should be admitted.

Beware of labelling pain as oesophageal or chest wall pain unless you have specific reasons that support this diagnosis.


Pitfalls
It is important to remember that oesophageal pain may be relieved with GTN and that some anginal pain may appear to be relieved by antacids. This is especially true of acute coronary syndrome where the pain may well be intermittent and appears to "settle".






DIAGNOSES FOR EXCLUSION
Having undertaken all of the above the flow chart (fig 6) will help you reach a diagnosis. It is vital to appreciate that included in the chart are:






Figure 6 Diagnoses for exclusion.





Acute coronary syndrome

Pulmonary embolism

Dissection of the thoracic aorta

Pneumothorax.

Interpretation of findings
These conditions require the patient to be admitted to hospital as soon as possible and it is important that these conditions are not missed. Thus if a convincing diagnosis of a condition other than these four cannot be reached the patient should be admitted to hospital. Individual symptoms or signs are unreliable (for example, there is no guarantee that a somatic pain is not originating from the heart or that heart pain will not disappear after the administration of an antacid). It is therefore unwise to exclude the diagnosis based on a single symptom, physical sign, or investigation. Instead it should be based on several supporting pieces of information.


TREATMENT AND DISPOSAL
Treat and Refer—ACS, dissecting aortic aneurysm, pleuritic chest Pain (depending on diagnosis and condition of patient), pneumothorax, gastrointestinal pain (depending on condition of patient or not settling with appropriate treatment)

Treat and Leave—stable angina, cervical root pain, chest wall pain, pleuritic chest pain (depending on diagnosis and condition of patient), gastrointestinal pain (depending on condition of patient or not settling with appropriate treatment)


FOLLOW UP ARRANGEMENTS (IF NOT ADMITTED)
Arrange review if indicated before normal working hours or, if not, notify the responsible GP with appropriate information at the start of normal working hours.





View this table:
[in this window]
[in a new window]
Table 3 Summary of causes and types of chest pain




FURTHER READING

Diagnosis

Panju AA, Hemmelgarn BR, Guyatt GH, et al. Is this patient having a myocardial infarction? JAMA 1998;280:1256–63.[Abstract/Free Full Text]

Klompas M. Does this patient have an acute thoracic aortic dissection? JAMA 2002;287:2262–72.[Abstract/Free Full Text]

ECG interpretation

Foster B.12 Lead electrocardiography for ACLS providers. Philadelphia: WB Saunders, 1996.

Meek S, Morris F. ABC of clinical electrocardiography: introduction. I—Leads, rate, rhythm, and cardiac axis. BMJ 2002;324:415–18. (http://bmj.bmjjournals.com/cgi/conte...l/324/7334/415)[Free Full Text]

Meek S, Morris F. ABC of clinical electrocardiography: introduction. II—Basic terminology. BMJ 2002;324:470–3. (http://bmj.bmjjournals.com/cgi/conte...4/7335/470?eaf)[Free Full Text]

Morris F, Brady WJ. ABC of clinical electrocardiography: acute myocardial infarction—Part I. BMJ 2002;324:831–4. (http://bmj.bmjjournals.com/cgi/conte...4/7341/831?eaf)[Free Full Text]

Meek S, Morris F. ABC of clinical electrocardiography: acute myocardial infarction—part II. BMJ 2002;324:963–6. (http://bmj.bmjjournals.com/cgi/conte...4/7343/963?eaf)[Free Full Text]

Channer K, Morris F. ABC of clinical electrocardiography: myocardial ischaemia. BMJ 2002;324:1023–6. (http://bmj.bmjjournals.com/cgi/conte.../7344/1023?eaf)[Free Full Text]

Heart and lung sounds

http://www.vh.org/adult/provider/internalm...lungsounds.html

Auscultation Assistant. (http://www.med.ucla.edu/wilkes/intro.html)

Treatment

Boehringer Ingelheim.Thrombolysis up front version 2.2. Bracknell: Boehringer Ingelheim, May 2003.

British Thoaracic Society. Guidlelines for the management of community acquired pneumonia in childhood. Thorax 2002;57(suppl 1):1–24.[Free Full Text]

British Thoaracic Society. Guidelines for the management of community acquired pneumonia in adults. Thorax 2001;56(suppl 4):1–64.[Free Full Text]

Joint Royal Colleges Ambulance Liaison Committee.Guidelines version 2. London: JRCALC Royal College of Physicians, 2002. (http://www.asancep.org.uk/JRCALC/guidelines.htm)