Cardiac arrest is a sudden loss of proper heartbeat caused by sudden disturbance in the heart's electrical impulses. This electrical disturbance results to abnormal or total cessation of the delivery of oxygenated blood to the vital organs of the body such as the brain. A person experiencing cardiac arrest could die within 5 minutes if there's no attempt to normalize the heart's rhythm.
Pathophysiology of a cardiac arrest
The heart has sinus node located at the right atrium responsible for generating paced electrical impulses that signals the heart muscle to contract and relax rhythmically. During cardiac arrest, there is a sudden disturbance of the electrical impulses causing arrhythmia or abnormal heartbeat. The heart could beat too slowly, too fast, or it could stop beating entirely, which is the onset of cardiac arrest. When the heart stops beating, there's a small window of opportunity to revive it to avoid partial or permanent damage to the brain. The damage could be debilitating or fatal.
Causes of cardiac arrest
There are rare causes of cardiac arrest some of which can trigger arrhythmias in a perfectly healthy person. Among these causes are misuse of drugs (illegal, OTC, or prescribed), electrical shock, or a chest trauma that interrupts the sinus node's release of electrical impulse.
But most cardiac arrests developed from preexisting heart condition that triggers heart failure. These causes are the following:
1. Congenital heart disease - This is the most common cause of cardiac arrest among young individuals. Hypertrophic cardiomyopathy for instance causes sudden deaths among young athletes who do not show signs of heart problems ever before. This is a genetic disorder and is present since birth. People who have undergone corrective congenital heart defect procedure are also at risk of cardiac arrest.
2. Electrophysiological abnormalities - The heart's natural ability to produce paced electrical impulse could fail on its own triggering cardiac arrest. This is often corrected by attaching an artificial pacemaker to the patient's heart.
3. Valvular heart disease - This is when the heart's valves narrowed causing the heart muscle to thicken. This could also weaken the heart muscle to the point where it can't properly pump blood to the different organs of the body.
4. Heart enlargement - When the heart is damaged due to blockage or a congenital heart defect, it could enlarge. When this happens, the heart muscles weaken and the patient becomes prone to developing arrhythmias.
5. Atherosclerosis - This is caused by build-up of cholesterol and other deposits in a person's major artery. The buildup causes blockage that diminishes the heart's ability to properly conduct electrical impulses for proper heartbeat.
Symptoms of cardiac arrest
Cardiac arrest remains the number one killer disease throughout the world because it often attacks without clearly noticeable symptoms. However, hours or minutes before cardiac arrest, the patient may experience lightheadedness, fatigue, shortness of breath, chest discomfort, palpitations, and sometimes vomiting. When a person is currently having cardiac arrest, he or she shows no pulse, no breathing, and a total loss of consciousness.