Causes

​A sudden cardiac arrest occurs when there is a dangerous form of electrical malfunction in the heart, known as life-threatening arrhythmia. This causes the patient’s heart to pump ineffectively, resulting in the inability of vital organs to receive blood and oxygen.

If the patient does not receive emergency treatment, death usually ensues within minutes. However, with immediate cardiopulmonary resuscitation (CPR) and treatment with automated external defibrillator (AED), the patient may recover with restoration of normal heart rhythm.

Risk Factors

Cardiac arrest usually develops in a person with pre-existing, possibly undiagnosed heart condition. These conditions include:

• Coronary artery disease, including a heart attack
• Heart failure, especially when the left ventricular ejection fraction is less than 30 to 35%
• Significant valvular heart disease
• Complex congenital heart disease
• Inherited arrhythmias or abnormal heart rhythms