“An estimated 1,000 Singaporeans die from sudden cardiac death (SCD) every year.”

This was shared by Clinical Associate Professor Ching Chi Keong, Senior Consultant from the Department of Cardiology and Director of Electrophysiology and Pacing at National Heart Centre Singapore (NHCS), a member of the SingHealth group.

Sudden death is usually caused by sudden cardiac arrest, which is a swift and unexpected loss of heart function. Sudden cardiac arrest (SCA) disrupts the normal pumping of blood throughout the body, and can lead to sudden cardiac death.

About half of these people are below the age of 60, according to a study carried out by NHCS in collaboration with the Health Sciences Authority. The study found that about 91 per cent of those who died from sudden cardiac death were males with a mean age of 46 ± 9 years.

Sudden cardiac arrest and heart attack: What is the difference?

“Sudden cardiac arrest is not the same as a heart attack. A heart attack happens because the heart’s blood supply is cut off, while sudden cardiac arrest is usually caused by electrical issues within the heart,” says Clin Assoc Prof Ching.

Sudden cardiac arrest is usually caused by an abnormality in the heart rhythm, known as arrhythmia.

Symptoms for cardiac arrest and heart attack also differ:

​Cardiac arrest symptoms

Sudden cardiac arrest often occurs without warning symptoms. A person with sudden cardiac arrest might lose consciousness, collapse suddenly and become pulseless.

Shortlived warning symptoms can include:

Heart attack symptoms

A heart attack can trigger life-threatening arrhythmia, leading to sudden cardiac arrest. The symptoms of a heart attack are typically more pronounced. They include:

  • Sudden onset of severe chest pain or discomfort lasting longer than 15 mins

  • Sudden onset of shortness of breath, with or without chest pain

  • New onset of chest pain or discomfort at rest or with minimal exertion

  • Cold sweat, nausea or lightheadedness typically associated with chest pain/discomfort or shortness of breath

Risk factors for sudden cardiac arrest

  • Personal or family history of coronary artery disease, cardiac arrest, heart attack, heart rhythm disorders, congenital heart defects, poor heart function and heart failure

  • Recurrent chest pain or fainting spells during physical exertion

  • Smoking

  • High blood pressure (hypertension)

  • High cholesterol (hyperlipidaemia)

  • Obesity

  • Diabetes

  • Excessive alcohol consumption

“A typical patient of sudden cardiac arrest is likely to be male, more than 35 years old and has a family history of early heart attack,” says Clin Assoc Prof Ching.

See page 2 to learn how arrhythmia (irregular heartbeat) can cause sudden cardiac arrest.

Ref: R14

Check out other articles on heart health:

Sudden Cardiac Arrest: Early Symptoms, Treatment and Tips

How to Survive a Heart Attack When Alone

Tips for a Healthy Heart

Sudden Chest Pains You Shouldn't Ignore

Heart Palpitations: When Are They Serious?

How a Viral Infection Can Affect the Heart

How Plaque Buildup Can Lead to a Heart Attack