The Causes Behind Sudden Cardiac Arrest (SCA): When the Heart's Rhythm Breaks

Learn how an irregular heart rhythm can lead to life-threatening conditions or Sudden Cardiac Arrest (SCA) in an article featuring Dr. Koh Kok Wei, Consultant Cardiologist at Subang Jaya Medical Centre, in TheStar's Malaysia.

The Hidden Threat: Understanding Sudden Cardiac Arrest (SCA)

Shocking Incidents on the Field
It is always shocking to witness athletes collapsing and dying on the sports field. Such tragic occurrences have been seen several times in the sports world. Malaysia experienced this heartache when national basketball player Jacky Ng Kiat Kee passed away during an invitational tournament in China. His death was due to sudden cardiac arrest (SCA), a leading cause of death among young athletes worldwide.

The Unpredictable Nature of Sudden Cardiac Arrest (SCA)
What makes sudden cardiac arrest (SCA) especially scary is how unexpectedly it strikes. It can happen to anyone at any time, often without any warning. Even young, fit, and healthy athletes can be affected by SCA, as has been seen many times before.

Immediate Response is Crucial
According to Dr Koh Kok Wei, Consultant Cardiologist at Subang Jaya Medical Centre (SJMC) and Malaysia Heart Rhythm Society chairperson, an SCA victim's life can only be saved if cardiopulmonary resuscitation (CPR) is started immediately.  "CPR alone cannot revive the victim. It can only ensure that the oxygen supply to the brain is maintained. To save the victim, getting him to an automated external defibrillator (AED) within 5 to 10 minutes is crucial because only an AED can restart the heart," he explains. 

In Penang last year, a 49-year-old man was revived by five teenagers with the help of CPR and AED, 12 minutes after he suffered cardiac arrest while playing football.

The question is what causes SCA and is there a way to prevent it?

Causes and Prevention of Sudden Cardiac Arrest (SCA) 
Dr. Koh explains that SCA occurs when the heart's electrical system malfunctions, causing erratic or irregular heartbeats, known as arrhythmia. Arrhythmia itself is not a disease but a manifestation of an underlying problem. Common causes include coronary artery disease, heart blockage, or injury from a previous heart attack. The most common cause is hypertrophic cardiomyopathy, the thickening of the heart muscles.

Sometimes, there are prior symptoms like palpitations, but often, there are no warning signs before the heart suddenly stops. The best way to prevent SCA is to diagnose and treat the underlying heart problem that might cause a cardiac arrest.

Detecting Arrhythmia
"There are many diagnostic procedures to detect arrhythmia, with the first step being an electrocardiogram (ECG). The problem with ECG is that it is much like taking a picture that captures the heart rhythm at one particular instant and the person's heart might just be beating normally then.

"If someone has a family history of sudden deaths or has risk factors related to heart diseases, such as diabetes and hypertension, they are advised to go for a more thorough heart screening, which includes an echocardiogram, treadmill stress test and Holter monitor," elaborates Dr Koh.

Sometimes, even these tests cannot detect arrhythmia, but Dr Koh emphasises that it does not completely negate the possibility of people with risk factors, especially those with a family history of heart disease, getting SCA.

"In such cases, a diagnostic procedure is undertaken whereby healthcare professionals induce SCA within the hospital. Yes, many people get scared when they hear that their heart will be stopped deliberately, but it is better to see if there is a problem within a controlled medical environment where the doctors and cardiologists are already prepared to restart the heart, than have it happen somewhere else," he assures.

Implantable Cardioverter Defibrillator (ICD)
For undetectable arrhythmias, the only preventive measure is an implantable cardioverter defibrillator (ICD), which detects malfunctions and can send shocks to restart the heart. However, the high cost of ICDs makes them unaffordable for many Malaysians, contributing to the low survival rate of SCA victims in the country.

Knowledge of CPR for cardiac arrest can save lives
"There is a dire lack of awareness regarding SCA," says Dr Koh, who also believes the lack of knowledge leads to many people not receiving the primary care needed in emergency situations."

Many Malaysians confuse SCA with a heart attack when they are completely different. Heart attacks can lead to SCA but there are other things that can cause it, too. This lack of awareness causes people to ignore the necessity of taking safety training such as CPR.

"Every public place should have AED machines and there should be clear instructions as to its location. There should also be a professional available at all times to assist in using the machine because most people do not know how," he adds.

Based on Dr Koh's comments, taking lifesaving training in CPR that also teaches you how to use AED should be made mandatory in schools, universities and workplaces, because these techniques are the only thing that stands between life and death.

Life after Sudden Cardiac Arrest (SCA)
The survival rate for sudden cardiac arrest (SCA) is extremely low in Malaysia. For the very few people who survive, the fight for their life does not end there.

When the heart stops pumping blood, the brain is deprived of oxygen, leading to various medical issues. The longer the brain goes without sufficient oxygen, the more severe the consequences, which can include memory loss, partial paralysis, and psychological problems like post-traumatic stress disorder (PTSD).

Stories of Sudden Cardiac Arrest Survivors 
SCA survivor Jasmine Wylie shares her experience, saying, "I have roughly three years missing from my memory - a few weeks before the attack to a few years after. It is like I am a different person now. There are fundamental things that are very different from who I was before the attack, such as the way I think, how I perceive the world, and how I store and retrieve information in my brain." Jasmine is part of an SCA survivors support group on Facebook.

Lynn Cassano Russell, another member of the group, describes her ongoing struggles, "I experience frequent seizures and had a mild anoxic brain injury. I suffer from severe fatigue and weakness that don't seem to get better with time. While I can still perform tasks like showering and doing my hair, it takes me twice as long as before and tires me out quickly. Sometimes my head feels like it is spinning and only lying down helps. Daily life is such a struggle that I have been put on permanent disability because of the lasting effects."

The Importance of Support and Awareness
Jasmine Wylie emphasises the often-overlooked mental health aspect of recovery and the value of support groups. "The knowledge and wisdom of other survivors have made such a huge impact on how I have dealt with things, and I am very thankful to live in a time where I can belong to an online community, as you don't meet very many SCA survivors in regular life," she shares.

Unfortunately, there is a significant lack of awareness about SCA in Malaysia, and there are no dedicated support groups for local survivors and their families. This gap highlights the urgent need for widespread life-saving training and the establishment of robust support systems for those affected by SCA.

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Keeping Your Heart in Check with SJMC Heart Centre
For those looking to stay on top of their heart health, Subang Jaya Medical Centre (SJMC) Heart Centre offers comprehensive care and advanced diagnostic services. With a team of experienced cardiologists, including Dr. Koh Kok Wei, SJMC Heart Centre is dedicated to preventing and treating heart conditions, ensuring that your heart remains healthy. Regular check-ups and early detection can make all the difference. Visit SJMC Heart Centre to take proactive steps in maintaining your heart health and preventing life-threatening conditions like SCA.

Find out more about Subang Jaya Medical Centre | Heart, Vascular & Thoracic