Cardiac means heart, and arrest means stop. So, quite literally, cardiac arrest means someone's heart has stopped. And when we say stopped, we mean it has stopped meaningful output of blood flow, which our bodies need to keep us alive. We will all eventually pass away because our hearts stop, it's just what causes them to stop that differs. In the case of SUDDEN CARDIAC ARREST, we are talking about someone who for no apparent or obvious reason, their heart suddenly and without warning, stops.

Sudden Cardiac Arrest (SCA) is an ELECTRICAL problem, and manifests in the heart rhythm becoming chaotic - it usually happens when there has been a disturbance in your heart's pumping action and it prevents blood flowing to your brain and other vital organs. SCA will result in death if it is not treated within minutes of it occurring. A heart attack is not a cardiac arrest - a heart attack is a PLUMBING problem in the heart - one or more arteries within the heart that are suffering from narrowing or blockages that cause the heart muscle to become deprived of sufficient blood flow and oxygen to keep it nourished. This heart that is under "attack" from lack of oxygen is at risk of becoming damaged the longer the attack goes on. However, for the most part, the person's heart is still pumping, so the brain and lungs and other muscles of the body are perfused, so the person will be able to talk, breath, move, and is conscious. They may experience chest pain, shortness of breath, fatigue, dizziness and other symptoms such as pain in the arm, shoulder or jaw area. A person who is having a heart attack needs medical assistance straight away. Call for emergency services, and keep the patient calm. When someone is in cardiac arrest however, it means that the person's heart is no longer pumping blood around their body - so their brain, lungs and other vital organs are no longer being perfused, and do not work. This person will be unconscious, unable to respond, unable to breath and unable to voluntarily move. This person needs emergency services called immediately, CPR commenced straight away, and an AED retrieved immediately, to defibrillate their heart as quickly as possible.

No - heart attack and sudden cardiac arrest are NOT the same thing. A heart attack can LEAD TO or CAUSE a sudden cardiac arrest, but they are different physiological events. A heart attack is usually due to the narrowing of one of the coronary arteries. This narrowing leads to reduced blood flow to the heart muscle - like all muscles in our body, our heart requires blood supply for it work properly - and when the oxygen in our blood is not reaching every part of the heart, it can cause numerous symptoms including chest pain, discomfort, shortness of breath, irregular heart beat, pain in jaw or throat, as well as exhaustion and anxiety. If a coronary artery becomes blocked and occludes the blood flow to the heart, then it could cause the heart to go into cardiac arrest - meaning that the heart will not be able to pump blood around the body, and stop beating in a functional way. Cardiac Arrest may be caused by a number of contributing factors - some of which are beyond a person's control. There are a range of "electrical" conditions that can cause a sudden cardiac arrest, as well as heart disease leading to an SCA in the event of a 100% blockage of the artery. Some SCA's are "unexplained" and have no underlying, or predisposing cause.

The symptoms of a sudden cardiac arrest are IMMEDIATE - hence the use of the word "SUDDEN" in the name of the event. Someone who is in cardiac arrest will be: 1) Unable to respond (you won't be able to wake them up) 2) Not breathing normally If you see someone collapse, or find someone who has collapsed, after checking for danger, and making sure that you will be ok if you render assistance, check the patient for a response - can you wake them up? If you cannot wake them up, call for emergency services and send for an AED immediately. Next, check to see if they are breathing normally. Normal breathing is quiet and effortless. If they are gasping, choking, gurgling, or if it sounds like they are snoring - combined with the fact that you cannot wake them up - start CPR and use an AED as soon as one is available.

Because the SCA patient's heart has stopped, it needs to be restarted. This can be done by a layperson in a lot of cases of cardiac arrest, if they have the right skills (CPR) and tools (an AED) nearby. Calling emergency services and getting paramedics dispatched early, combined with good CPR and early use of an AED within the first 3-5 minutes of the patient's collapse, can result in survival rates as high 65-72%. The three steps outlined above are known as the Chain of Survival - CALL, PUSH, SHOCK. Three simple things that anyone can do to help save a life when a person's heart has stopped. Emergency response times (currently around 15-21 minutes in Australia) greatly affect the survival rate of SCA patients. Our paramedics do an incredible job, but they simply cannot be everywhere they are needed at one time. In the case of cardiac arrest, there are simple things that bystanders can do that will drastically help increase the patient's chance of survival. Other contributing factors to the patient's chance of survival will include how effective the Chain of Survival is - that is, how quickly the event is recognised, how rapidly EMS teams are called, how well CPR is performed, and whether or not there is a defibrillator (AED) to revert the patient's heart rhythm if it can be shocked.

CPR alone is unlikely to revive a patient who is in cardiac arrest. Cardiac arrest is usually the result of an electrical dysfunction within the heart, and some types of those dysfunctions (or arrhythmias) are what we call "shockable rhythms". When a patient has a "shockable rhythm" it is vital that an AED is used quickly, because that "shockable rhythm" will deteriorate rapidly over time. For every minute that passes, the patient's chance of surviving decreases by around 10% - because the heart rhythm deteriorates over time to a rhythm called "asystole" which is a flat line - and this cannot be shocked by an AED. The problem is that humans are unable to tell if a patient is in a shockable rhythm or not - they need electronic equipment to determine the patient's rhythm. That's where an AED comes into play, because it can read the patient's rhythm and make that determination. An AED can be used by anyone, without any training required, because it does all of the analysis and makes all the decisions for the user. The user just needs to listen to the audible instructions, or some models have video instructions, and follow them! It is very simple. If the heart is in a shockable rhythm, the AED will advise a shock be delivered to the patient. Having an AED within 3 minutes of someone who experiences an SCA vastly increases that person's chances of survival. In Australia we have seen data that reports if an AED is used within the first 3-5 minutes, the survival rate can be as high as 65-72%! This is so much greater than the 5% that currently survive. An AED will not work in all cases of cardiac arrest, and has less chance of working the longer the time period from collapse to first use of the AED. That is why it is imperative that there are more AEDs available in the community to be used, and more people who know that they are there to be used by THEM, and not by doctors, nurses, paramedics, or "trained" people. Anyone can use an AED, and when they do, there is much more chance of the patient surviving.

Anyone can suffer a Sudden Cardiac Arrest, anywhere at any time. There are risk factors that may predispose someone to being more at risk, but sometimes, there is no way of knowing. A person may look fit, healthy, and athletic, but they may still suffer a SCA. Some of the risk factors include: 1) Family history of coronary artery disease or another form of heart disease/heart problems. 2) Smoking 3) High blood pressure and cholesterol 4) Obesity and diabetes 5) Having a predominantly sedentary lifestyle 6) Drinking too much alcohol 7) Age - likelihood of SCA increases with age 8) Being male - men are two to three times more likely than women to suffer an SCA. 9) Having had a heart attack before 10) Using illegal drugs 11) Nutritional imbalances such as low potassium or magnesium levels.

Sudden Cardiac Arrest affects more than 25,000 people in Australia every year. That means, for around 70 people per day, their heart suddenly and unexpectedly stops beating.

The survival rate for out-of-hospital cardiac arrest is only 5%. That means, that for every 1 person that survives an out-of-hospital cardiac arrest, 19 do not survive!