EIGHTY per cent of sudden cardiac arrest happens at home. Based on data from countries with effective emergency response systems, currently, only eight per cent of people who suffer a cardiac arrest survive. There is no available data for Jamaica, but, given the absence of an effective emergency response system, the survival rate would no doubt be significantly less.

While sudden cardiac arrest (SCA) is a significant public health crisis, it is often misunderstood. SCA is not a heart attack. A heart attack occurs when a vessel supplying blood to the heart becomes blocked and interrupts blood flow to the heart. This causes heart muscle to die.

Sudden cardiac arrest occurs when the heart’s electrical system malfunctions and the heart stops beating. Most of these deaths occur with little or no warning, as many victims appear healthy with no known heart disease or other risk factors. The most common cause of sudden cardiac arrest is a disturbance in the heart rhythm called ventricular fibrillation.

Note, however, that a massive heart attack may be followed by cardiac arrest.

RESUSCITATION AND SUDDEN CARDIAC ARREST

Once a cardiac arrest occurs, cardiopulmonary resuscitation (CPR) and defibrillation are required within the first few minutes to restore electrical activity to the heart and revive the heart’s pumping function. Availability of Automated External Defibrillators (AEDs) is critical for rapid response to cardiac arrest, especially in the out-of-hospital scenario.

The AED is a portable machine which analyses the heart’s rhythm. If necessary, a computerised command will instruct the user to press a button to deliver an appropriate shock to restore the normal operation of the heart. These devices are fail-safe and will not cause injury to the user, nor will they deliver a shock if none is needed. For patients in ventricular fibrillation, studies show that if early defibrillation is provided within the first minute, the odds are 90 per cent that the victim’s life can be saved. After that, the rate of survival drops 10 per cent with every minute. As many as 30-50 per cent of SCA victims would likely survive, if CPR and AEDs were used within five minutes of collapse.

For CPR Week, June 15-21, 2014, The Heart Foundation of Jamaica is calling on Jamaicans to learn how to give CPR.

Don’t be afraid; your actions can only help. If you see an unresponsive adult who is not breathing or not breathing normally, call for help and push hard and fast on the centre of the chest. If you are uncomfortable giving breaths, just continue doing hands-only CPR.

Anyone can learn CPR, and everyone should. The life you save is most likely to be someone you love.

Dr Hugh Wong , consultant emergency physician at the KPH, is also director of Emergency Cardiac Care at the Heart Foundation of Jamaica.