Sudden cardiac arrest - Who is at higher risk and what can be done to reduce the risk?

A sudden cardiac arrest occurs when there is an abrupt loss of heart function. It is a medical emergency that can lead to sudden cardiac death.

It can occur due to a variety of heart conditions, with the most common cause from a sudden onset of abnormal heart rhythm (arrhythmia). A cardiac arrest can also occur during a heart attack.

Want to find out more about sudden cardiac death and heart attack?

Send in your questions and Clinical Associate Professor Jonathan Yap, Consultant from the Department of Cardiology at National Heart Centre Singapore (NHCS), a member of the SingHealth group, will answer your questions in this month’s ‘Ask the Specialist’ Q&A forum.

This 'Ask the Specialist' forum has closed. Thank you for your interest and participation.

1. Question by yongcc36
I starting to pay attention to my heart when I have first onset "severe heart attack alike" symptoms in 2018. I have done ALL the necessary heart screening (except CT/MRI) and the results are negative however the symptoms did not disappear till date. My concern out of the test is i feel tougher in the treadmill test (been repeating the test every year), the recent test was stopped when target HR achieved and it took longer for recovery (to normal HR). I do have sleep disorder (insomnia) which I'm not sure if that's the reason of accelerating the underlying heart condition? What else I could do? Thank you Dr.

Answered by Clinical Associate Professor Yap:
Importantly, you should aim to lead a healthy lifestyle and diet. You should regularly screen for cardiovascular risk factors like cholesterol, sugar and blood pressure. It is not clear what symptoms you are experiencing but if you are persistently symptomatic, it is advisable to seek a formal consultation with a doctor to assess if this is actually related to the heart.

2. Question by MM2709
I experience chest tightness, nausea and some light-headedness from time to time, even when at rest. For a female above 50yo, do these symptoms indicate heart issues? I am within healthy weight and have low cholesterol levels (for both total cholesterol and LDL levels), without any other medical issues.  Besides CT scans, are there any other non-invasive checks I can go for to determine if I have underlying heart issues and what's the cost?

Thank you for your kind attention.

Answered by Clinical Associate Professor Yap:
It is good to hear that your weight is within healthy range and that your choleseterol is well controlled. If you are having chest tightness, especially if this occurs during exertion, you should see a doctor for a formal assessment. If deemed necessary by your doctor, there are various tests that can done to check for coronary artery disease, these include stress tests, such as an exercise stress test that uses a treadmill.

3. Question by teikchai
Dear Prof Jonathan Yap,
Good morning.
I am under the care of a Dr who has been investigating my "breathlessness" problems. I am writing to you to seek an additional opinion please.
Can you pls tell me whether I have a high risk of getting a Cardiac Arrest, Heart Attack or Stroke?

I am very active physically. Every weekend I work in my little garden for a few hours, I run about 7kms 2 or 3 times a week (doing HITTS quite ofter) and I also play Golf every Sun. In addition, after my last consultation with my Dr, I have made an effort to fully abstain from all alcohol, eat very much more greens and have avoided red meats where all possible. I get regular 7 hours sleep every night.

I look forward to your views and advice, and also answering any other questions that you may have.
Many thanks in advance.

Answered by Clinical Associate Professor Yap:
It is heartening to hear that you are leading a healthy lifestyle with regular exercise and healthy diet. This will help in lowering your risk of a cardiovascular event. It will also be good to check your cardiovascular risk factors including cholesterol, blood pressure and sugars. It is not clear what breathless issue you have, as you seem to be able to do much exercise. However, it is good that you are already seeing a doctor for a proper assessment.

4. Question by chow78
I always have this dull aching pain on the right side of my chest. It usually last 1-2 days. Seen a GP before who keeps saying that it's because I hardly exercise or stretch and it's the muscle stretch that is causing the dull pain. How do I when to trust the GP and when to see the specialist?

Answered by Clinical Associate Professor Yap:
Cardiac chest pain is generally brought on by exertion or stress and relieved by rest. The pain tends to be a heavy sensation in the centre or left side of your chest. Of course, there are exceptions to this. It is good that you have consulted your GP on this. If the symptoms persist or worsen, you may discuss with your GP if a heart specialist referral is warranted.

5. Question by ac
Hi Dr, 
As a layman, I'm confused what is the difference between sudden cardiac arrest and heart attack. How would you describe the difference to a lay person?
How is the treatment different for sudden cardiac arrest and for a heart attack?
Also, is it true that even healthy, active people can get sudden cardiac arrest? If that is true, then how is it preventable?

Answered by Clinical Associate Professor Yap:
A heart attack occurs when the blood vessels supplying your heart are blocked, resulting in injury to your heart muscles. Sudden cardiac arrest occurs when your heart stops suddenly. This can be due to a heart attack amongst many other reasons. The treatment for sudden cardiac arrest will include basic and advanced cardiopulmonary resuscitation to try and "revive" the heart, following which treatment is directed towards the cause of the cardiac arrest. Treatment of heart attack includes medications, risk factor and lifestyle control and opening up of the blocked heart arteries either by ballooning/stenting or coronary bypass, depending on further assessment of the individual’s condition

6. Question by Kenneth
Hi Dr,
I am currently 37 years of age. For the past 2 months, encountering these symptoms: constant lower left/right abdominal pain, occasional chest pain, numbness in arms and legs. Had done full health screening, CT calcium score and CT abdominal with constract.

No major findings, CT calcium score of zero. I do have high LDL for a couple of years. 
BP and heart rate are in the normal range. I am lightweight of 55kg.

Should I be worried about my cardiac health?

Answered by Clinical Associate Professor Yap:
Cardiac chest pain is generally brought on by exertion or stress and relieved by rest. The pain tends to be a heavy sensation in the centre or left side of your chest. Your symptoms seem quite vague and you should be properly assessed by a doctor. Having a calcium score of zero does portend a lower risk profile. If your LDL is high, it is advisable to work on lowering it.

7. Question by PegarX
Hi Dr,
My nephew got diagnose with brugada but is asymptomatic and no family history. is he at higher risk for sudden cardiac arrest?  if so, how best to prevent it from happening and is it necessary for his family members to undergo testing as well?
With thanks, Pegar

Answered by Clinical Associate Professor Yap:
As your nephew has been diagnosed with brugada, the risk of a sudden cardiac arrest may be higher as compared to the general population. As he is asymptomatic, it may be in his favour. It is advisable for him to consult his doctor to discuss on the medications to take or avoid to reduce the risk of sudden cardiac arrest. He should also actively seek medical treatment for any febrile illness to expediently bring down his fever, if any. His family members could also consider going for screening, as there is a possible genetic component to the disease.

About Clin Assoc Prof Jonathan Yap

Clinical Associate Professor Jonathan Yap is a Consultant with the Department of Cardiology at NHCS. His sub-specialty interest is in interventional cardiology, pulmonary hypertension and structural heart disease including transcatheter aortic valve interventions (TAVI) for aortic stenosis.

Clin Assoc Prof Yap has a keen interest in education and research. He is involved in several ongoing research projects and has published extensively in many international scientific journals. He is also the editor of an electrocardiogram (ECG) teaching app.

Because #healthiswealth #healthforgood

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