Sudden Cardiac Arrest in Healthy Individuals: Causes and Risk Factors

While sudden cardiac arrest (SCA) is often associated with pre-existing heart conditions, it can also occur in seemingly healthy individuals. Understanding the potential triggers and physiological responses can help raise awareness and promote preventive measures.

Triggers of Cardiac Arrest in Healthy People

Even individuals with no known heart disease can experience cardiac arrest due to sudden and intense physical or emotional stressors. Events such as severe trauma, extreme fright, sudden emotional shock, excessive physical strain, serious systemic illnesses, or severe infections can all act as powerful stressors on the body.

The Role of Stress Hormones

These stressors activate the body's fight-or-flight response, leading to a surge in adrenaline and other catecholamines. While these hormones are essential for survival in dangerous situations, excessive levels can have toxic effects on the heart. Elevated catecholamine levels can impair myocardial function, potentially leading to arrhythmias, ventricular fibrillation, or even cardiac arrest.

Coronary Spasms and Heart Attacks

In some cases, intense stress or stimulation can cause the coronary arteries to spasm. This can lead to acute myocardial infarction (heart attack), especially in individuals without prior heart disease. A severe blockage or spasm can deprive the heart muscle of oxygen, triggering sudden cardiac arrest.

Electrolyte Imbalances and Acidosis

Another important factor is the disruption of the body's electrolyte balance. Conditions such as hypokalemia (low potassium) or hyperkalemia (high potassium), along with metabolic acidosis, can interfere with the heart's electrical system. These disturbances can lead to life-threatening arrhythmias and ultimately cardiac arrest, even in otherwise healthy individuals.

Prevention and Awareness

Although sudden cardiac arrest in healthy individuals is relatively rare, understanding the potential triggers is crucial. Managing stress, avoiding excessive physical strain, and maintaining proper electrolyte balance are important preventive strategies. Public awareness and access to emergency response tools like automated external defibrillators (AEDs) can also significantly improve survival rates when such events occur.