SADS - Sudden Arrhythmia Death Syndrome

By Dr T. Subramaniam (Siva)

In a medical context the term SADS is most often used in reference to Sudden Arrhythmia Death Syndrome. However, over the past few years the phrase, Sudden Adult Death Syndrome or SADS has been adopted by the media for referring to the more general notion of a sudden death of an apparently fit and healthy young person.

Sudden Adult Death Syndrome events are defined as non-traumatic, non-violent, unexpected occurrences resulting from cardiac arrest within as little as six hours of previously witnessed normal health.

This can also be called Sudden Death Syndrome – SDS, or Sudden Cardiac Death – SDC. Sometimes, it is also called Sudden Unidentified Death Syndrome – SUDS, when the pathologist finds no cause of death.

It is often difficult to consider that someone who is apparently young and fit may be at risk. There have been a number of reported incidents of misdiagnosis culminating in a tragedy that could have been avoided.

Sporty youngsters stress their hearts the most. If they have an underlying cardiac abnormality they are more likely to be at risk. Sport itself does not lead to cardiac arrest, but it can act as a trigger for a young person to die suddenly by exacerbating an undetected condition.
The majority of young sudden deaths are due to inherited forms of heart muscle disorder and irregular heartbeat.

The conditions which if undetected can lead to Sudden Cardiac Death are listed below:
* Hypertrophic Cardiomyopathy - (HCM)
* Arrhythmogenic Right Ventricular Cardiomyopathy – (ARVC)
* Dilated Cardiomyopathy – (DCMM)
* Myocarditis
* Coronary Artery Disease
* Ion Channelopathies (Long QT,
Brugada, Lev-Lenegres)
* Wolff (Wolfe) Parkinson White Syndrome (WPW)
* Coronary Artery Anomalies (CAAs)
* Marfan Syndrome
* Restrictive Cardiomyopathy

Other cardiac conditions: Endocardial Fibro Elastosis (EPE), Tachycardia

The commonest cause of sudden death in those under 30 years of age is Hypertrophic Cardiomyopathy (HCM). It is estimated that 10,000 people in the UK have this condition. The second most common cause is Arrhythmogenic Right Ventricular Cardiomyopathy – (ARVC).

Some of the conditions are caused due to an abnormality in genes. They are a hereditary disease in nature, i.e. it is passed on from the parents. The first two belong to this category.

A few are caused by viral infections, thereby causing Autoimmune Disorder. Coxsackie-B and ECHO are some of the commonest viruses. Dilated Cardiomyopathy, Myocarditis and Endocardial Fibro Elastosis belong to this category.

Ion Channelopathies and Wolff (Wolfe) Parkinson White Syndrome (WPW) are caused by defects in the pathway of electrical impulses in the heart.

Yet others like Coronary Artery Disease and Restrictive Cardiomyopathy are caused by other conditions such as Arteriosclerosis (narrowing of blood vessels), high blood pressure, cigarette smoking, excessive alcohol intake, other diseases (such as Amyloid, Sarcoidisis, Carcinoid Syndrome, Systemic Sclerosis) and radiotherapy to the chest.

Apart from these there are also congenital problems (due to birth defects) which cause conditions such as Marfan Syndrome and Coronary Artery Anomalies (CAA).

The symptoms of the above conditions are as follows:
* Shortness of breath
* Chest pain – usually brought on by physical exertion
* Palpitation – rapid, irregular heartbeat
* Light headedness; black outs
* Ankle swelling
* Lack of energy
* Generalised aches and pains
* Feeling feverish

If you suffer from any of these symptoms it does not mean that you have any of the cardiac conditions mentioned above. But if you visit your General Practitioner (GP) he or she may suggest that you undertake some tests and may refer you to a cardiologist (a heart specialist).

The investigative tests that are carried out are as follows.
* Chest x ray
* Electrocardiogram – ECG
* Echocardiogram
* Doppler Study

What should you do if diagnosed with any of the above disorders?

If your tests prove positive your specialist will advise you on lifestyle modifications. You will probable be advised not to participate in 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 you may not necessarily present any symptoms and can live a fairly normal life.

Treatments vary from one person to another depending on several criteria such as the type , age of the patient, stage of the disease and the immune system. The different forms of treatment are listed below.
* Drugs
* Electrical Cardioversion.
* Pacemaker
* ICD (implantable Cardioverter
Defibrillator)
* Catheter Ablation
* Surgical Ablation
* Heart Transplantation

Prevention
* Avoid smoking
* Avoid excessive alcohol consump tion
* Healthy diet
*Early detection by undergoing ECG testing and cardiac screening

Steps To Be Taken By The Government Offering ECG testing and cardiac screening to the general public to detect cardiac abnormalities. Increase supply of much needed medical equipment to clinics around the UK in order to detect cardiac abnormalities and to prevent sudden cardiac death.

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