What is Cardiac Arrest?
Cardiac arrest is the abrupt loss of heart function in a person who may or may not have diagnosed heart disease. Sudden cardiac arrest occurs suddenly and often without warning. It is triggered by an electrical malfunction in the heart that causes an irregular heartbeat (arrhythmia). The time and mode of death are unexpected. It occurs instantly or shortly after symptoms appear. With its pumping action disrupted, the heart cannot pump blood to the brain, lungs and other organs. Seconds later, a person loses consciousness and has no pulse. Death occurs within minutes if the victim does not receive treatment.
Doctors are nowadays seeing sudden cardiac arrest not only more often, but more alarmingly it is being seen increasingly in younger people too.
Urbanization with increasing lifestyle diseases like hypertension and diabetes, coupled with increased stress levels and high risk behaviors like smoking, tobacco use and alcohol intake have increased the risks alarmingly.
Risk is the least in healthy individuals and is the highest in patients with heart diseases. The first presentation of an underlying heart disease can be a sudden cardiac arrest.
Only 5-10% of the lucky people survive an out of hospital sudden cardiac arrest and that is because they received immediate medical attention.
Each year, more than 350,000 emergency medical services-assessed out-of-hospital cardiac arrests occur in the United States.
Is Heart Attack Same As Cardiac Arrest?
No. The term “heart attack” is often mistakenly used to describe cardiac arrest. While a heart attack may cause cardiac arrest and sudden death, the terms don’t mean the same thing. Heart attacks are caused by a blockage that stops blood flow to the heart. A heart attack (or myocardial infarction) refers to death of heart muscle tissue due to the loss of blood supply, not necessarily resulting in the death of the heart attack victim.
Cardiac arrest is caused when the heart’s electrical system malfunctions. In cardiac arrest death results when the heart suddenly stops working properly. This may be caused by abnormal, or irregular, heart rhythms (called arrhythmias).
A common arrhythmia in cardiac arrest is ventricular fibrillation. This is when the heart’s lower chambers suddenly start beating chaotically and don’t pump blood. Death occurs within minutes after the heart stops. Cardiac arrest may be reversed if CPR (cardiopulmonary resuscitation) is performed and a defibrillator is used to shock the heart and restore a normal heart rhythm within a few minutes.
What are the signs of a Cardiac Arrest?
There are usually no symptoms before a cardiac arrest and, without immediate treatment, it will be fatal. If someone is in cardiac arrest:
- they won’t be conscious
- they won’t be responsive
- they won’t be breathing, or breathing normally.
A cardiac arrest is a medical emergency. If you witness a cardiac arrest, you can increase the person’s chances of survival by phoning 999 immediately and giving CPR.
What causes a Cardiac Arrest?
The most common cause of a cardiac arrest is a life-threatening abnormal heart rhythm called ventricular fibrillation (VF).
Ventricular fibrillation happens when the electrical activity of your heart becomes so chaotic that the heart stops pumping and quivers or ‘fibrillates’ instead.
Heart-related causes of Cardiac Arrest:
- Coronary heart disease
- Heart attack
- Cardiomyopathy and some inherited heart conditions
- Congenital heart disease
- Heart valve disease
- Acute myocarditis (inflammation of the heart muscle)
- Heart conduction disorders that make you more likely to experience abnormal heart rhythms, such as Long QT syndrome.
Other causes of Cardiac Arrest:
- Drug overdose
- Severe haemorrhage – losing a large amount of blood
There’s no sure way to know your risk of sudden cardiac arrest, so reducing your risk is the best strategy. Steps to take include regular checkups, screening for heart disease and living a heart-healthy lifestyle with the following approaches:
- Don’t smoke, and use alcohol in moderation (no more than one to two drinks a day).
- Eat a nutritious, balanced diet.
- Stay physically active.