Key Difference: Cardiac Arrest is a heart condition where the heart does not contract properly, thereby failing to effectively circulate blood to the other organs. Cardiac arrest is brought on by irregular beating of the heart that causes it to stop supplying blood flow to the other organs, including the brain. Asystole is a medical term in which the electrocardiography monitor shows a flatline or no cardiac electrical activity. Asystole is when there is no cardiac electrical activity present and the heart is no longer contracting or pumping blood throughout the body.

Cardiac arrest and asystole are two conditions that are often confusing for many people that have not been active in the medical field. These terms are often used to describe the condition that the patient might be in. Cardiac arrest and asystole are both related to the heart and the heartbeat. In both conditions, the heart does not function properly or stops the function completely, resulting in many people to become confused as to what these two conditions exactly are. Cardiac arrest is a condition where the heart does not contract properly and there is no proper circulation of blood to the rest of the body. Asystole is the condition where the heart completely stops beating and there is no cardiac activity.

Cardiac Arrest is a heart condition where the heart does not contract properly, thereby failing to effectively circulate blood to the other organs. Cardiac arrest is brought on by irregular beating of the heart that causes it to stop supplying blood flow to the other organs, including the brain. Cardiac arrest is also known as cardiopulmonary arrest or circulatory arrest. The heart has an internal electrical system that allows it to control the rhythm of the heart; any changes to the rhythm can cause the heart to either beat too fast, too slow or stop beating completely. These changes are known as arrhythmias. The lack of blood flow leaves the other organs starved for oxygenated blood. The lack of oxygen to the brain causes the person to faint. If the person does not receive help during the first five minutes of fainting, it can result in permanent damage to the brain.

Cardiac arrest can be a cause of Coronary heart disease, cardiac abnormalities such as cardiomyopathy, cardiac rhythm disturbances, hypertensive heart disease, congestive heart failure, etc., trauma, overdose, drowning, smoking, obesity, lack of physical exercise, etc. Cardiac arrest brought on suddenly is known as Sudden Cardiac Arrest (SCA) and causes the heart to stop beating completely. Cardiac arrest differs from heart attack as in a heart attack, the heart does not receive the oxygenated blood and all the while it continues to beat and pump until the cells die completely. In cardiac arrest, the heart itself stops beating, though it still receives constant supply of oxygenated blood.

Symptoms of cardiac arrest include fainting and loss of pulse or heartbeat. The person stops breathing as the heart no longer pumps. The person that suffers a cardiac arrest must receive quick cardiopulmonary resuscitation (CPR) to keep the heart pumping the brain from losing cells. The longer it takes the person to receive help, the more chances that they may have loss of memory, brain damages or less chances of survival. Defibrillation (or shocking the heart) is another way to revive the heart. Implantable cardioverter-defibrillators (ICDs) and pacemakers are used to ensure that the person does not suffer from another cardiac arrest episode in the event of arrhythmia.

Asystole is a medical term in which the electrocardiography monitor shows a flatline or no cardiac electrical activity. An electrocardiography (ECG) machine is a monitor the heart rate or electrical activity of the heart over a long period of time. The ECG machine is attached to the patient using electrodes and monitors the pulses and the heartbeats translating them into a rhythm graph on the screen. The screen measures the rate and regularity of the heartbeat, the size and position of the chambers, any damage to the heart, effects of drugs or devices used to regulate the heart. Asystole is when there is no cardiac electrical activity present and the heart is no longer contracting or pumping blood throughout the body.

Asystole is one of the methods used by a medical professional to declare a person clinically dead. A person can become asystolic due to a number of reasons including damage to the heart, disease, loss of blood, drug overdose, spike in potassium levels, oxygen deprivation, uncommon heartbeat, cardiac arrest, etc. Asystolic shows up as a flat line on the electrocardiograph. When a person goes into asystole, the person must be quickly revived using CPR. Many other methods or medications can also be used including atropine, epinephrine, vasopressin, internal cardiac massage (the person is opened up and pressure is applied directly to the heart) and defibrillation.

The danger with falling asystolic is that the longer the person is in this condition, the more the brain cells die because of lack of oxygen. Many people who become asystolic end up dying. If a person has been in this condition for more than 15 minutes, the medical professionals automatically stop trying to revive the person and declare them dead as the brain has already died.

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