Sudden cardiac arrest (SCA) occurs when the heart abruptly stops functioning, leading to haemodynamic collapse and sudden death. It can manifest within an hour of symptom onset in witnessed cases or within 24 hours in unwitnessed cases. In autopsy findings, it is described as a natural, unexpected death due to cardiac or unknown causes.

SCA is responsible for nearly 50% of all cardiovascular deaths, with up to half of these being the first sign of an underlying cardiac issue. The causes of SCA vary with age. In younger individuals, primary electrical diseases, cardiomyopathies, myocarditis, and coronary anomalies are more prevalent. In contrast, older populations typically experience SCA due to chronic structural heart diseases, often associated with coronary artery disease, acute coronary events, or valvular heart conditions.

Genetic cardiac conditions are linked to 25–49% of SCA cases in the young, potentially affecting family members as well. Reversible factors, such as electrolyte imbalances (e.g., hypokalaemia and hypomagnesaemia), ischaemia, coronary spasms, drug-induced arrhythmias, or even lifestyle factors like dehydration and unsupervised use of supplements, contribute to some cases. While reversible causes may account for up to half of SCA instances, identifying them remains challenging.

Athletes, despite appearing fit, may develop cardiac issues from dehydration, inadequate diets, or misuse of supplements or hormones aimed at muscle growth. Additionally, inherited conditions affecting the heart's structure or electrical function can lead to fatal arrhythmias. When SCA strikes, the heart ceases to pump blood, halting oxygen delivery to vital organs. Without immediate intervention—ideally within three minutes—death or irreversible brain damage may occur.

Some warning signs, such as dizziness, fainting during exercise, chest pain, palpitations, and unexplained seizures, may precede SCA. Recognising and addressing these signs can save lives.

Preventing sudden cardiac arrest: key measures

• Regular cardiovascular health check-ups

• Screening for diabetes, hypertension, and obesity, alongside regular moderate exercise

• Avoiding unsupervised use of supplements, chemicals, or hormones

• Adopting a balanced diet and avoiding smoking or tobacco use

• Managing blood pressure, cholesterol, and blood sugar levels

• Genetic testing for families with a history of early cardiac arrest

• Proactive steps like these, combined with awareness of the risks, can help mitigate the threat of SCA among young, seemingly healthy individuals.

The writer is a Consultant at the Cardicare Heart and General Hospital.
Email: cardiac_hospital@yahoo.com