Medical Information
Hypertrophic Cardiomyopathy (HCM)
What is Hypertrophic Cardiomyopathy?
Sudden Death Syndrome is the term, which is now used to describe unexpected and unexplained death occurring in apparently healthy young people. When the heart is examined by an expert pathologist a probable cardiac cause of death is found in the majority. Hypertrophic Cardiomyopathy (HCM) is the most common cause of sudden death in those under 30 years of age. It is a relatively uncommon heart disease although is estimated that ten thousand people in the United Kingdom have the condition. In a healthy heart beat results from electrical signals starting at the top and passing down through the heart. HCM is a disease, which interrupts these vital electrical signals, which keep the heart beating. It is an incurable disease, which causes excessive thickening of the myocardium (the muscle in the heart). Heart muscle may thicken in individuals who have high blood pressure or who have prolonged athletic training, but in HCM patients the muscle thickens without an obvious cause. HCM was first recognised in the late 1950?s and has been known by a number of names, hypertrophic obstructive cardiomyopathy", "idiopathic hypertrophic sub-aortic stenosis" and "muscular sub-aortic stenosis" but it is generally referred to as HCM.
What causes Hypertrophic Cardiomyopathy?
HCM is caused by abnormalities in genes which make the protein responsible for contraction of the heart (sarcometric contractile proteins) It is a hereditary disease i.e. it is passed on from parents. In the majority of cases the condition is inherited from a defective gene of one of the parents. It is a disease that can affect both men and women of any ethnic origin. The condition is present from conception and excessive growth of the muscle may begin before birth when the foetal heart is developing. The overgrowth of muscle interferes with the heart?s normal contracting and relaxation.
Symptoms
Symptoms and severity can vary from person to person. They may begin in infancy, childhood or in middle or elderly life. Some patients never have any symptoms of HCM and the disease can cause unexpected sudden death during or after excessive exertion. The reason for the onset of symptoms is not known and no particular symptom or complaint is unique to HCM sufferers. Many do not even realise that they have the disease and it is not until a member of the family presents that other family members are screened and are found to have the condition. As it is a hereditary condition if a parent presents then there is a fifty fifty chance that each child will also have the disease. The most common symptoms of HCM are: Shortness of breath Chest pains (usually brought on by physical exertion) Palpitation (rapid, irregular heart beat) Light-headedness, blackouts If you suffer from any of these symptoms it does not mean that you have HCM but if you visit your General Practitioner he/she may suggest that you undertake some tests any may refer you to a cardiologist (a heart specialist).
How is Hypertrophic Cardiomyopathy diagnosed?
Because the symptoms of HCM are similar to those of other conditions certain tests need to be carried out. An electrocardiogram (or ECG) records the electrical signals from the heart. The test is painless. Electrodes are placed on the chest, ankles and wrists. If the patient has HCM the ECG usually reveal an abnormal electrical signal due to the thickening of the muscle and further tests may be carried out. More often than not an echocardiogram (ECHO) will also be carried out. Again this is painless and is very similar to an ultrasound scan performed on pregnant women. In this test the ECHO produces a picture of the heart. It is an entirely safe test and the thickness of the heart muscle can be measured. Together with equipment called a Doppler, the ultrasound can produce a colour image of the blood flow within the heart and can measure the heart?s contractions and filling. Advances in molecular genetics means that in some centres, the condition may be diagnosed using a blood test.
What Treatment Is Available?
There is no cure at present for Hypertrophic Cardiomyopathy. Treatment is aimed at preventing complications and improving symptoms. Treatment can be obtained through drugs, specialised pacemakers, or in some cases, surgery. Drugs are given initially when a patient presents some or all on the symptoms. A variety of drugs are used in the treatment of HCM and the choice of treatment will vary from patient to patient. The relieve palpitations, breathlessness and chest pains beta-blockers may be used. These are widely used for other types of heart disease and high blood pressure and work by slowing the heart beat which reduces its force of contraction. Other drugs may be used to try and reduce the thickening of the muscle. However, in patients with severe symptoms, who don?t respond to well to treatment with drugs, surgery may be suggested. A surgical myectomy, where some muscle is removed, is usually successful in the relief of symptoms. The operation involves removing a portion of the thickened muscle, which widens the outflow tract in the left ventricle and relieves obstruction. There are other forms of treatment, which are occasionally recommended for people with HCM. Electrical Cardioversion ? this is for sufferers of atrial fibrillation (irregular heart beat). It is carried out under general anaesthetic and involves the patient being given a small electric shock to the chest, which restores the normal heartbeat. Pacemaker ? In HCM sufferers the normal electric signal may fail; if so a pacemaker can be fitted. This is a small box containing a battery, which is placed in the chest under the skin and ensures the heart receives the necessary electrical signals. ICD (Implantable Cardioverter Defibrillator) ? In cases which rapid heart beat cannot be controlled by drugs an ICD may be fitted. This is similar to a pacemaker where a box is implanted under the skin in the abdomen. The box has fine wires which are attached to the heart to record an deliver electrical impulses in the absence of normal electrical impulses.
What Should You Do If You Are Diagnosed With Hypertrophic Cardiomyopathy?
If your tests prove positive your specialist will advise you on lifestyle Modifications. You will probably be advised not to participate in continuous strenuous activities e.g. competitive sports. For many people the condition should not significantly interfere with their lifestyle and can be controlled by drugs. It will be necessary for you to have annual check-ups. However, the severity of the disease varies from person to person and even if you have been diagnosed with HCM you may not necessarily present any symptoms and can live a fairly normal life. We are greateful to Camilla Wheeler of the Community Education Department, Yorkshire Television, for permission to reproduce information on Hypertrophic Cardiomyopathy from a factsheet produced to coincide with a 3-D programme on Sudden Death Syndrome, first transmitted in April 1995
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)
What is ARVC?
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is probably the second most common cause of unexpected sudden death in the young. The disorder is characterised by a progressive replacement of normal right ventricular muscle cells by fibrous tissue and fat. Initially this may only involve specific regions of the right ventricle but later on it becomes global and may even involve the ventricle as well. ARVC was first recognised in the late 1970?s and the Cardiovascular Group at the University of Padova in Italy have developed particular expertise in the condition.
What Causes ARVC?
The precise cause of ARVC is not known. The condition is normally familial and is passed on in the genes from one generation to the next. The pattern of inheritance is autosomal dominant such that the child of an affected parent will have 50% chance of inheriting the abnormal gene. The disease affects men and women equally and has been recognised in people of diverse ethnic origin.
Symptoms
Clinical presentation is usually with symptoms of arrhythmia and occasionally with sudden death. Typical arrhythmia symptoms are of rapid heart beat associated with light-headedness or fainting episodes. Unlike most cardiomyopathies, shortness of breath and chest pains are unusual symptoms and tend only to occur in older patients.
How is ARCV Diagnosed?
The diagnosis of ARVC can be problematic and usually requires specialist expertise. The investigations are similar to those performed in the diagnosis of hypertrophic and other cardiomyopathies and include an electrocardiogram and a two dimensional echocardiogram. The features, however, are often very subtle as in the early stages the condition is often confined only to the right ventricle. Other methods of imaging the right side of the heart are sometime useful and these include magnetic resonance imaging.
What Treatment Is Available?
The majority of patients with this condition are asymptomatic for many years unless arrhythmias develop. Treatment in the majority then aims to prevent or at least control arrhythmia with drugs. When drug treatment is unsuccessful, implantable cardioverter defibrillator and other specialised treatments may be necessary, these include: Catheter Ablation ? This involves the delivery of electrical energy via a catheter inserted in the groin to the area in the right side of the heart where the arrhythmia is originating from. The overall effect is to create a small scar which is incapable of transmitting any arrhythmia. Surgical Ablation ? In individuals whom the arrhythmias are originating from many different sites in the right side of the heart. Occasionally it is necessary to perform open-heart surgery. At the operation, the electrical pathway of the arrhythmia can be mapped, identified and destroyed.
Dilated Cardiomyopathy (DCM)
What is Dilated Cardiomyopathy?
In Dilated Cardiomyopathy the main pumping chambers of the heart are dilated and contract poorly. This results in a low output of the blood from the heart and features of heart failure, with build up of fluid behind the left side of the heart leaving the congestion in the lungs and breathlessness. Occasionally the right side of the heart is also involved with fluid accumulating in the body tissues, particularly the ankles and abdomen.
What Causes Dilated Cardiomyopathy?
The cause of Dilated Cardiomyopathy remains uncertain, but it is probable that there are many different factors which are important. These include viral infection. Usually viral infections are self-limiting illnesses as the body?s defence mechanism is able to control the virus, prevent it from spreading and kill it. Enteroviruses are common causes of viral infections often presenting with flu like symptoms. One of the Enteroviruses, CoxsackieB, can affect the heart but does not usually cause permanent damage. In some instances however, the evidence suggests that the virus may either persist within the heart or trigger an auto immune process that continues to damage the heart muscle.
Auto Immune Disease
Normally the body's immune system provides a defence against infection. Occasionally however, for reasons that are uncertain, the immune system may be activated mistakenly to attack its own self. Viruses are believed to be a common cause or trigger of the auto immune process which is seen in several conditions including rheumatoid arthritis where the joints are damaged, juvenile onset diabetes mellitus where the pancreas is damaged and the thyroiditis where the thyroid gland may be involved. In these auto immune conditions, antibodies circulating in the blood develop to the tissue or organ which is being attacked. In dilated Cardiomyopathy, antibodies against the heart are found in approximately 30% of patients and in a similar proportion of the asymptomatic relatives. This and other evidence suggests that an auto immune component may play an important part in the development and progression of Dilated Cardiomyopathy. The significance of the cardiac antibody is asymptomatic first degree relatives is under study; in other conditions (diabetes) the presence of the antibody in asymptomatic relatives identifies those at risk of developing the condition.
Genetics
Recently it has become apparent that Dilated Cardiomyopathy is familial in at least 20% of cases. Evaluation, however, of the family has potential to clarify the genetic contribution to the development of the condition within individual families.
Other Aspects
Excessive alcohol consumption has a depressant effect on the heart muscle and can exacerbate an underlying cardiomyopathy. Abstinence from further alcohol prevents further damage to the heart muscle and often allows the heart to recover.
Pregnancy
There is a form of Dilated Cardiomyopathy which develops during late pregnancy and in the period shortly following childbirth. The cause is uncertain, but it is believed that the additional demand of pregnancy on the heart may be triggering factor in the development of the condition.
Symptoms
Symptoms will depend on the stage and evolution of the condition. Shortness of breath ? this is a common symptom which becomes worse with exertion. It is caused by the build-up of fluid and elevated pressure in the lungs. When severe, there may be marked breathlessness, even at rest. Lack of energy ? If the cardiac output is low and the body is not able to get enough blood, the muscles are unable to contract normally and easily become tired. Ankle swelling ? when the right side of the heart fails to expel the blood it receives, the fluid builds up in the body tissues. This is called oedema and usually presents initially in the ankles. Chest pain ? this may occur at rest or during exercise. Though the cause of the pain is usually not clear, it is important to emphasise that the pain is not due to coronary artery disease (coronary arteries are normal in dilated cardiomyopathy) and that the pain does not cause damage to the heart. Arrhythmias ? arrhythmias are a common complication. The heart can either beat too rapidly (tachycardia) or too slowly (bradycardia). Such arrhythmias are often associated with an uncomfortable awareness of the heart beat (palpitations) and/or accompanied by dizziness and fainting.
How Is Dilated Cardiomyopathy diagnosed?
This diagnosis relies on a careful history and physical examination to document symptoms or abnormalities on the physical examination suggestive of cardiac failure. An electrocardiogram should be performed to look for evidence of damage to the heart
What Treatment Is Available?
Treatment aims to improve the symptoms of heart failure and to prevent complications, particularly those arising from the development of arrhythmia. Heart failure treatment includes water tablets (diuretics) to rid the body of excess fluid, angiotensin converting enzyme inhibitors to reduce the amount of work the heart has to do, and digoxin to improve the contractile performance of the heart. Anti arrhythmic drugs may be necessary if arrhythmias are documented. Occasionally Brady arrhythmias develop and a pacemaker may be necessary. A small number of patients with dilated cardiomyopathy do not respond to medical treatment and deteriorate to such an extent that their quality of life and prognosis is poor. At this stage, an individual should be referred to a specialist hospital for assessment of the potential role of cardiac transplantation.
Restrictive Cardiomyopathy (RCM)
What is Restrictive Cardiomyopathy?
Restrictive Cardiomyopathy is the rarest of the cardiomyopathies. It is characterised by increased stiffness of the heart muscle, usually due to scar tissue, which prevents adequate filling of the chambers of the heart. The actual pumping action of the heart is usually normal. The cause of scar tissue is unknown in the majority of cases. In some cases it may be due to very rare conditions which cause infiltration of the heart, infection and drugs. Hypertrophic Cardiomyopathy may also behave in a similar fashion. In advanced cases reduced filling of the left heart chamber causes a build up of pressure and occasionally fluid in the lungs. Reduced filling of the right heart causes a build up of pressure and fluid in the lower abdomen.
Conditions that can cause Restrictive Cardiomyopathy
· Idiopathic
· Endomyocardial Fibrosis
· Infiltrative disorders (Amyloid, Sarcoid, Haemochromatosis)
· Carcinoid Syndrome
· Systemic Sclerosis
· Radiotherapy to the chest
Symptoms
The main symptom of Restrictive Cardiomyopathy are breathlessness and ankle swelling. In some cases the diseased heart may beat rapidly or with an abnormal pattern resulting in palpitations. Occasionally the rhythm disturbance is severe enough to cause "blackouts". Sudden death is a recognised feature.
Diagnosis
The diagnosis is confirmed with a combination of ECG and Echocardiography. In some cases the patient will undergo an invasive cardiac catheter study to measure the pressures within various chambers of the heart.
Genetics
A familial form of the disease is recognised but it is not know how common this is. There is no cure for Restrictive Cardiomyopathy but a variety of drugs are available to treat symptoms. Patients with severe heart failure, despite medication, are assessed for heart transplantation.
Treatment
Is with diuretics and drugs which control disturbances of heart rhythm. Very advanced cases, when medical therapy proves ineffective, are referred for transplantation.
Myocarditis
What is Myocarditis?
The term Myocarditis implies inflammation of the heart muscle. It is usually due to a viral illness and the most commonly implicated viruses are Coxsackie B and Echo virus. Viral Myocarditis is relatively common and most cases are very mild and therefore never come to the attention of the doctor or are never detected clinically. Some cases are severe and lead to considerable impairment in the capacity of the pump efficiency resulting in severe heart failure. Sudden death is a recognised complication, usually occurring during or just after exertion. It is the result of poor contraction of the heart or electrical instability of the heart due to the inflammation of the heart muscle.
Symptoms
Most patients feel feverish and have generalised aches and pains as with any other viral illness. When the heart is severely affected the patients feel tired and breathless. Chest pain and palpitations are relatively common.
Signs
Apart from a rapid heart rate, the doctor may not find any other abnormalities when examining the patients with mild Myocarditis; however, in severely affected individuals there is evidence of heart failure.
How Is Myocarditis diagnosed?
The ECG will show transient changes which are usually non-specific and occur in many other cardiac diseases, however, in light of the patient?s symptoms and the presence of a fever may raise the suspicion of Myocarditis. An echocardiogram (ultrasound of the heart) will reveal an enlarged heart which is poorly contracting. In very mild cases both the ECG and the echocardiogram may be normal and in these situations one should exercise caution and not participate in any sporting activity when symptoms of a flu like illness are present. In patients presenting with florid cardiac symptoms and signs the diagnosis can be confirmed by a biopsy (small specimen of the heart) taken from the right ventricle.
Treatment
Complete rest is indicated in all patients! Patients with heart failure and complicated electrical disturbances of the heart require hospital admission to manage these complications. The use of steroids in reducing inflammation of the heart is reserved to very sick patients who have clear evidence of the condition on the biopsy.
Prevention of Sudden Death
Refrain from sporting activity until all symptoms have subsided and the ECG and echocardiogram appearances are normal.
Clinical Outcome
Over ? of the patients improve within two weeks without any complications. Approximately 10% of patients proceed to develop dilated cardiomyopathy and require life long treatment with heart failure medication.
Coronary Artery Disease (CAD)
This is usually associated with recognised risk factors such as raised blood fats, cigarette smoking and high blood pressure. Rarely there may be a developmental abnormality of the coronary arteries such that one or other vessel is either missing or has an abnormal origin, such that the muscle it is supplying is in jeopardy.
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, sex, 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.
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.
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
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.
Wolff - Parkinson-White Syndrome (WPW)
What is Wolff (Wolfe)-Parkinson-White Syndrome? Wolff (Wolfe)-Parkinson-White (WPW) is a very rare cause of sudden death. It results from an additional electrical connection between the atria (upper chambers of the heart) and the ventricles (lower chambers of the heart). This extra or accessory electrical pathway is present in approximately 1.5 per 1,000 people. It runs in families in less than 1% of cases. In the majority it is completely silent and only detected on a routine ECG. In a small proportion of patients the extra electrical pathway allows conduction of the electrical pathway generating an electrical circuit which produces a very rapid heart rate. Most patients tolerate this well but some experience very troublesome palpitations, light-headedness and blackouts. A very small minority of patients may die suddenly from ventricular fibrillation.
Symptoms
Palpitations are the main symptoms. They can occur at any time and some patients learn to control them by holding their breath for prolonged periods. In many instances the palpitations remain until they are terminated by medical therapy in the accident and emergency department.
Signs
When the patient is experiencing palpitations the heart rate is usually in excess of 150 beats per minute. When the patient has no symptoms there is nothing to find on examination.
How is Wolff (Wolfe)-Parkinson-White diagnosed? WPW is diagnosed by performing an ECG. The ECG usually shows two abnormalities when the patient is free of symptoms ? a short PR interval and a delta wave. It is often an incidental finding during a routine ECG check as part of a medical insurance or detected by a cardiologist when a patient is referred with palpitations.
Treatment
The ideal treatment in patients with symptoms is to destroy the extra electrical pathway, a procedure termed radio frequency catheter ablation. This is done by passing a wire into the heart, often via the large artery (femoral artery) in the leg. The abnormal pathway is located by electrical stimulation and destroyed by passing a high current through it. This takes approximately 2-3 hours and requires one night in hospital. For patients above 25 years without any symptoms there is no need for further tests. Younger patients (under 25 years) are most at risk of sudden death and require further tests to assess their risk of developing life threatening electrical disturbances. This is best done by performing an exercise test under the supervision of a cardiologist. The abrupt disappearance of the delta wave on the ECG as the heart rate increases is a good sign. Obviating the need for any further investigation, however, if this does not happen then further electrophysical testing is recommended before one can be reassured.
Coronary Artery Anomalies (CAAs)
What are CAAs
The heart is supplied by two main arteries known simply as the left coronary artery and the right coronary artery. Both arteries are branches of the largest artery in the body which is the aorta. The aorta in turn, arises from the left ventricle which is the main pumping chamber of the heart. The left and right coronary arteries originate from the left and right side respectively. Occasionally both arteries originate from the right side of the aorta. The anomaly or oddity is usually safe but in a few unfortunate cases can predispose to exercise related death making coronary artery anomalies the second commonest cause of death in young athletes (aged below 25 years) after the cardiomyopathies.
Symptoms
Warning symptoms are sometimes present and include chest pain or blackouts during physical exercise. The exact mechanisms for the cause of death is not entirely certain but it is thought that the abnormal path taken by the artery causes it to "kink" or "become squashed" between large vessels which are greatly stretched with blood during exercise. The consequent loss of blood supply to the heart can lead to the development of a heart attack or electrical abnormality of the heart, producing sudden death.
How are CAAs Diagnosed
Screening for this coronary artery anomaly is possible using ultra sound imaging of the heart which is essentially the same equipment used to diagnose cardiomyopathy. In thin athletic individuals the aorta and the origins of both coronary arteries are easy to visualise. In those individuals which symptoms in whom the coronary arteries cannot be seen with the ultrasound it is possible to perform a more detailed, yet non-evasive (not requiring introduction of needles or small tubes into the body) test known as a MRI (Magnetic Resonance Imaging) scan which is good in visualising the coronary arteries. Coronary artery anomalies may or may not run in families but the abnormality is always looked for when screening any individual with a family history of premature sudden death.
Treatment
Treatment involves surgical plumbing of the left coronary artery to the left side of the aorta. Many other coronary anomalies have been described which are generally without the risk of exercise related death.
Marfan Syndrome
What Is Marfan Syndrome?
The Marfan Syndrome is an inherited disorder of connective tissue which affects many organ systems, including the skeleton, lungs, eyes, heart and blood vessels. This condition, first described by Dr Marfan in 1896, can affect both boys and girls of any race or ethnic group. It is estimated that over 5,000 people in the United Kingdom have Marfan Syndrome. A syndrome is a collection of physical features which, when they occur together, enable a physician to recognise a certain condition. Most affected people will not show all the signs and complications of Marfan Syndrome.
What Causes Marfan Syndrome?
Connective tissue, which holds the body together, binding skin to muscle, muscle to bone, is made of fine fibres and "glue". This tissue provides the stretchy strength of tendons and ligaments around joints, and in blood vessel walls. It is also important in eye and lung. In Marfan Syndrome a fine fibre called fibrillin is deficient in all these locations, accounting for the unusual stretchiness and weakness of tissues. A gene for Marfan Syndrome has been located on chromosome 15. It directs the production of fibrillin. An error in this gene results in diminished fibrillin production. Marfan syndrome is, in 75% of cases, an inherited disorder of connective tissue ? 25% of cases occur as a result of a spontaneous mutation. Each offspring of an affected person bears 50-50 chance of inheriting the condition. The affected child will probably affected in the same way as the parent, but it may also be more or less severely affected. In 75% of cases one parent will also be affected, so apparently unaffected parents should be screened. The severity and pattern of disease are variable even within one family.
How Can You Recognise Marfan Features?
Signs and severity of the condition vary greatly. Diagnosis is made after a careful physical examination, particularly focusing on the three main systems involved:
· Eyes
· Heart
· Skeleton (including the jaw).
Certain tests such as an Echocardiogram (an Electrocardiogram is insufficient), chest and skeletal X- rays and a careful eye examination using a slit lamp are useful in making the diagnosis.
Salient Features
· Eyes: Subluxation or dislocation of lens, myopia and unstable refraction, detachment of retina, strabismus, glaucoma.
· Mouth: High arched palate, crowding of teeth.
· Heart: Dilations of ascending (and sometime descending) aorta, incompetence of aortic and mitral valves, aneurysm and dissection of aorta.
· Skeletal: Tall thin build, with long limbs and fingers, spinal curvature, flattening of chest (with pigeon or funnel deformity), with arm span greater than height.
What Treatment is Available?
All complications of the Marfan?s Syndrome are amenable to correction. The major life threatening complication affects the aorta, which is the major vessel arising from the main pumping chamber of the heart. Due to abnormalities in the connective tissue in the wall of the aorta there is enlargement of the aorta. When the aorta becomes very enlarged or dilated there is a possibility of tear developing in the wall (aortic dissection) or the entire aortic wall rupturing (aortic rupture). Both conditions are a medical emergency. Rupture of the aorta results in death within seconds or minutes whereas with dissection of the aorta there is often time for treatment.
To prevent both complications it is important to keep an eye on the size of the aorta. This is easily done by performing regular ultrasonic scans of the heart in those individuals affected by the condition.
If the aorta shows signs of becoming enlarged, further enlargements can be prevented by using drugs known as beta-blockers, which reduce the pressure (and hence the stress) within the aorta. These drugs do not serious complications but should not be given to anyone with asthma.
If treatment with these drugs does not halt enlargement then an operation is required. This involves strengthening the wall of the aorta with a supportive tube made from Dacron. The tube is placed so that it is in contact with the inner wall of the aorta and the enlarged portion of the aorta is sewn around this tube. Results from the operation are very good and although the operation is very delicate very few people die as a result of the operation.
Enlargement of the aorta can cause disturbance in the function of the aorta valve (leaky aortic valve). The function of the aortic valve is to prevent blood from going back into the heart once it has been pumped out. Malfunction of the valve causes a leakage of blood back into the heart. If the leak is very severe it causes breathlessness. In these situations the aortic valve is replaced by a prosthetic valve at the time of repair of the aorta.
Another complication which affects three quarters of people with Marfan?s but can sometimes be serious in 1 in 10 patients is leaking of the mitral valve. The abnormal connective tissue of the mitral valve causes it to leak mitral when the heart contracts. Constant leaking of the valve causes the main pumping chamber to work harder. If the leak is severe the main pumping chamber starts to tire and eventually fails. The main symptoms when this occurs are breathlessness, tiredness and palpitation. In this situation the valve is surgically repaired or a new prosthetic valve is inserted.
Apart from the heart the other site where complications can have serious consequence is the lungs. The lung can occasionally collapse (pneumothorax) out of the blue. This is rarely life threatening but sometime a one way valve is created which allows air into the thorax but does not allow air out. The build up of air causes an increase in pressure in the thorax which can compress the normal lung and the heart and the great vessels causing collapse and rapid death. Fortunately the complication is easy to recognise and can be treated very promptly by inserting a small needle into the affected side to let the air out.
Complications affecting the eyes, mouth and the skeleton are not life threatening and can be corrected.
Sports Guidelines
PLEASE REMEMBER EACH PATIENT IS AFFECTED DIFFERENTLY AND OUR GENERAL RECOMMENDATIONS NEED TO BE DISCUSSED WITH THE PATIENT?S OWN MEDICAL ATTENDANTS AND PARENTS
RECOMMENDED ? (NOT HIGH LEVEL COMPETITION)
Swimming, Cycling (on the level), Badmington, Cricket, Netball, Tennis, Archery, Fencing, Sailing, Table Tennis, Skiing, Canoeing, Golf, Bowls, Skating, Shotput, Discus, Javelin, Racketball, Football (no "heading"), Hockey.
The child should be allowed to rest when tired.
CONTRAINDICATED
(TO PREVENT DAMAGE TO: E = EYE; H = HEART; J = JOINTS; L = LUNGS)
Boxing (E)
Distance Running (H, J)
Rugby (H, J)
Weight-Lifting (H, J)
Rowing (H, J)
Squash (E, H)
Karate/Judo (H, J) Sky Diving (L)
Hang Gliding (L)
Deep Sea Diving (L)
High Altitude Mountaineering (L)
High Diving (E)
Trampolining (J)
Wrestling (H, J)
Marfan Syndrome
What Is Marfan Syndrome?
The Marfan Syndrome is an inherited disorder of connective tissue which affects many organ systems, including the skeleton, lungs, eyes, heart and blood vessels. This condition, first described by Dr Marfan in 1896, can affect both boys and girls of any race or ethnic group. It is estimated that over 5,000 people in the United Kingdom have Marfan Syndrome. A syndrome is a collection of physical features which, when they occur together, enable a physician to recognise a certain condition. Most affected people will not show all the signs and complications of Marfan Syndrome.
What Causes Marfan Syndrome?
Connective tissue, which holds the body together, binding skin to muscle, muscle to bone, is made of fine fibres and "glue". This tissue provides the stretchy strength of tendons and ligaments around joints, and in blood vessel walls. It is also important in eye and lung. In Marfan Syndrome a fine fibre called fibrillin is deficient in all these locations, accounting for the unusual stretchiness and weakness of tissues. A gene for Marfan Syndrome has been located on chromosome 15. It directs the production of fibrillin. An error in this gene results in diminished fibrillin production. Marfan syndrome is, in 75% of cases, an inherited disorder of connective tissue ? 25% of cases occur as a result of a spontaneous mutation. Each offspring of an affected person bears 50-50 chance of inheriting the condition. The affected child will probably affected in the same way as the parent, but it may also be more or less severely affected. In 75% of cases one parent will also be affected, so apparently unaffected parents should be screened. The severity and pattern of disease are variable even within one family.
How Can You Recognise Marfan Features?
Signs and severity of the condition vary greatly. Diagnosis is made after a careful physical examination, particularly focusing on the three main systems involved:
· Eyes
· Heart
· Skeleton (including the jaw).
Certain tests such as an Echocardiogram (an Electrocardiogram is insufficient), chest and skeletal X- rays and a careful eye examination using a slit lamp are useful in making the diagnosis.
Salient Features
· Eyes: Subluxation or dislocation of lens, myopia and unstable refraction, detachment of retina, strabismus, glaucoma.
· Mouth: High arched palate, crowding of teeth.
· Heart: Dilations of ascending (and sometime descending) aorta, incompetence of aortic and mitral valves, aneurysm and dissection of aorta.
· Skeletal: Tall thin build, with long limbs and fingers, spinal curvature, flattening of chest (with pigeon or funnel deformity), with arm span greater than height.
What Treatment is Available?
All complications of the Marfan?s Syndrome are amenable to correction. The major life threatening complication affects the aorta, which is the major vessel arising from the main pumping chamber of the heart. Due to abnormalities in the connective tissue in the wall of the aorta there is enlargement of the aorta. When the aorta becomes very enlarged or dilated there is a possibility of tear developing in the wall (aortic dissection) or the entire aortic wall rupturing (aortic rupture). Both conditions are a medical emergency. Rupture of the aorta results in death within seconds or minutes whereas with dissection of the aorta there is often time for treatment.
To prevent both complications it is important to keep an eye on the size of the aorta. This is easily done by performing regular ultrasonic scans of the heart in those individuals affected by the condition.
If the aorta shows signs of becoming enlarged, further enlargements can be prevented by using drugs known as beta-blockers, which reduce the pressure (and hence the stress) within the aorta. These drugs do not serious complications but should not be given to anyone with asthma.
If treatment with these drugs does not halt enlargement then an operation is required. This involves strengthening the wall of the aorta with a supportive tube made from Dacron. The tube is placed so that it is in contact with the inner wall of the aorta and the enlarged portion of the aorta is sewn around this tube. Results from the operation are very good and although the operation is very delicate very few people die as a result of the operation.
Enlargement of the aorta can cause disturbance in the function of the aorta valve (leaky aortic valve). The function of the aortic valve is to prevent blood from going back into the heart once it has been pumped out. Malfunction of the valve causes a leakage of blood back into the heart. If the leak is very severe it causes breathlessness. In these situations the aortic valve is replaced by a prosthetic valve at the time of repair of the aorta.
Another complication which affects three quarters of people with Marfan?s but can sometimes be serious in 1 in 10 patients is leaking of the mitral valve. The abnormal connective tissue of the mitral valve causes it to leak mitral when the heart contracts. Constant leaking of the valve causes the main pumping chamber to work harder. If the leak is severe the main pumping chamber starts to tire and eventually fails. The main symptoms when this occurs are breathlessness, tiredness and palpitation. In this situation the valve is surgically repaired or a new prosthetic valve is inserted.
Apart from the heart the other site where complications can have serious consequence is the lungs. The lung can occasionally collapse (pneumothorax) out of the blue. This is rarely life threatening but sometime a one way valve is created which allows air into the thorax but does not allow air out. The build up of air causes an increase in pressure in the thorax which can compress the normal lung and the heart and the great vessels causing collapse and rapid death. Fortunately the complication is easy to recognise and can be treated very promptly by inserting a small needle into the affected side to let the air out.
Complications affecting the eyes, mouth and the skeleton are not life threatening and can be corrected.
Sports Guidelines
PLEASE REMEMBER EACH PATIENT IS AFFECTED DIFFERENTLY AND OUR GENERAL RECOMMENDATIONS NEED TO BE DISCUSSED WITH THE PATIENT?S OWN MEDICAL ATTENDANTS AND PARENTS
RECOMMENDED ? (NOT HIGH LEVEL COMPETITION)
Swimming, Cycling (on the level), Badmington, Cricket, Netball, Tennis, Archery, Fencing, Sailing, Table Tennis, Skiing, Canoeing, Golf, Bowls, Skating, Shotput, Discus, Javelin, Racketball, Football (no "heading"), Hockey.
The child should be allowed to rest when tired.
CONTRAINDICATED
(TO PREVENT DAMAGE TO: E = EYE; H = HEART; J = JOINTS; L = LUNGS)
Boxing (E)
Distance Running (H, J)
Rugby (H, J)
Weight-Lifting (H, J)
Rowing (H, J)
Squash (E, H)
Karate/Judo (H, J) Sky Diving (L)
Hang Gliding (L)
Deep Sea Diving (L)
High Altitude Mountaineering (L)
High Diving (E)
Trampolining (J)
Wrestling (H, J)
Other Cardiac Conditions: Endocardial Fibroelastosis (EFE)
What is EFE?
The term ENDOCARDIAL FIBROELASTOSIS (EFE) refers to the thickening of and the replacement of the heart muscle with fibrous tissue. It may be related to viral infections, such as the Coxsackie virus (a form of common cold) or rarely, may have an inherited nature. Doctors feel that the inevitable fatal outcome is triggered by a gene once the virus has been contracted. Unfortunately, it is frequently fatal in affected children.
Genetics
The doctors are, as yet, unable to identify the gene.
Treatment
If identified before death there is no cure for the condition except for anti-arrhythmic drugs as short-term treatment, or in longer term, a heart transplant.
Diagnosis
There is to date no clear information as to how a many children die of this condition, also how many cot deaths are actually caused by EFE and not identified as such. It is a fact that some parents do not find out the cause of death in their children due to the lack of expertise and investigation carried out at post-mortem.
Tachycardia
Definition
A heart rate exceeding 100 beats per minute.
Classification
A tachycardia can be either physiological (normal response) or pathological. Examples of a physiological tachycardia are during exercise, in pregnancy or in situations of anxiety or excitement (?flight, fright, fight?). A pathological tachycardia can be due to either a primary cardiac abnormality or a non-cardiac factor. Non-cardiac factors may include anaemia, over-activity of the thyroid gland or chronic liver disease. In these situations the heart itself is normal and is purely responding to increased ?demand? due to other abnormalities. Tachycardia of primary cardiac origin is best classified according to the site of origin of the electrical activity generating the heart rhythm. There are four chambers in the heart with the two upper chambers (atria) being electrically connected to the lower chambers (ventricles) via an atrio-ventricular node (AV node). The electrical impulse is normally generated by the sino-atrial node (SA node), situated in the right atrium.
Tachycardia can be divided as follows:
· Tachycardia originating in the atria:
Sinus tachycardia
Atrial tachycardia
Atrial flutter
Atrial fibrillation
· Tachycardia originating in the AV nodes:
Re-entry tachycardia
· Tachycardia originating in the ventricles:
Sustained ventricular tachycardia
Non-sustained ventricular tachycardia
Symptoms
Individuals with tachycardia can present with a variety of symptoms. Most are well and unaware of their tachycardia but symptoms can include:
· Shortness of breath
· Palpitations
· Chest tightness or pain
· Dizziness or being light-headed
· Collapse
· Passing large volumes of urine
Tachycardias of ventricular origin tend to be symptomatic more often.
Management
If tachycardia is suspected investigations are conducted to diagnose the exact nature, as treatment depends on the type of tachycardia. Tests may include resting ECG, 24 hour ECG recording, exercise ECG and in some rare cases invasive electrophysiological studies. The patients may also need investigations to look for other heart disease causing tachycardia (e.g. high blood pressure, coronary artery narrowing). Obviously non-cardiac causes of tachycardia also need to be investigated (e.g. thyroid disease). Treatment is mostly by medication (e.g. beta-blockers) but in some cases may require radio frequency catheter ablation or implantation of pacemakers or defibrillators. Other factors contributing to heart disease also need addressing.
Antibiotic Prophylaxis
What is Antibiotic Prophylaxis?
This term refers to the use of anitbiotics to prevent the infection of the inner lining of the heart (infective endocarditis), particularly the heart valves. Antibiotic prophylaxis is used in patients who are considered to be at a high risk of developing infective endocarditis and are undergoing any procedure where infection may be introduced in the blood stream such as a dental procedure or surgery.
Who is at risk?
Individuals at risk include patients with abnormalities of the heart valves (usually detected on physical examination by a heart murmur), prosthetic material within the heart (e.g. metallic heart valve) or ?holes? in the heart.
Treatment
The prophylaxis is usually in the form of a singe or double large dose of a penicillin antibiotic. If the individual is allergic to penecillin, then erythromycin is used.