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Cardiac arrest: causes, signs and symptoms

Cardiac Arrest: Causes, Signs and Symptoms


Cardiac arrest is a medical emergency where a person's heart suddenly stops beating. That's why it is also known as sudden cardiac arrest. If the loss of blood supply to the brain and other organs is not treated right away, a person may lose consciousness, become handicapped, or perhaps pass away. When the heart abruptly and unexpectedly stops pumping, cardiac arrest happens. If this occurs, the blood supply to the brain and other important organs is interrupted. Certain arrhythmias that stop the heart from pumping blood result in cardiac arrests.


Causes of Cardiac Arrest


It is possible for a cardiac arrest to be caused by a heart condition, or to happen without warning. However, some of the leading causes of cardiac arrest are:

  • Arrhythmia and ventricular fibrillation: Arrhythmia is the term for when the electrical signals in the heart malfunction and lead to an irregular heartbeat. A kind of arrhythmia called ventricular fibrillation is the most common reason for cardiac arrest. Instead of the heart normally pumping blood, ventricular fibrillation, a rapid heartbeat, causes the heart to tremble.
  • Enlarged heart or cardiomyopathy: The heart muscle dilates or thickens, leading to abnormal contractions of the heart.
  • Coronary artery disease: This form of heart disease develops when plaque buildup in the coronary arteries causes them to thicken and narrow, which reduces blood flow to the heart. Coronary artery disease can cause heart failure or arrhythmias, both of which can result in cardiac arrest if left untreated.


Other causes of cardiac arrest may include:

  • Blood loss
  • Valvular heart disease
  • Lack of oxygen
  • Increased levels of magnesium and potassium


Cardiac Arrest: How to identify?


If a person shows the following things he might be going through cardiac arrest. However, there may be situations where a cardiac arrest is not accompanied with any signs or symptoms. Some of the common cardiac arrest symptoms include:

  • If suddenly there is a loss of consciousness
  • If someone suddenly falls or passes out 
  • If someone is not breathing, breathing ineffectively, or gasping for air.
  • Doesn’t respond to you even after shaking or shouting at him
  • If there is no pulse
  • Fatigue
  • Dizziness
  • Shortness of breath
  • Nausea
  • Chest pain
  • Heart palpitations (fast or pounding heartbeat)
  • Loss of consciousness

Cardiac Arrest and Heart Attack: What's the difference?


Heart attacks and cardiac arrest are two distinct heart disorders, even though the phrases are frequently used synonymously. A blockage in the arteries that prevents blood flow to the heart causes a heart attack. The cardiac muscle tissue will deteriorate as a result of the lack of oxygen and blood flow. Because heart attacks can change the electrical signals in the heart, they can raise the risk for cardiac arrest. It's more probable that a heart attack caused cardiac arrest when it happened abruptly and there were no other heart diseases present.


Cardiac Arrest: What to Do?


In an event of a cardiac arrest, the most important thing is to call emergency services and start cardiopulmonary resuscitation (CPR). Cardiac arrest is a life-threatening medical emergency that when not treated quickly can be fatal. CPR or cardiopulmonary resuscitation is a technique in which the chest is compressed along with giving rescue breathing. It delivers oxygen to the lungs and circulates oxygenated blood until a normal breathing and functional heartbeat can be recovered. Knowing how to perform CPR could help you save others' lives. A medical emergency team may use individually or a combination of cardiopulmonary resuscitation (CPR) and defibrillation. Defibrillation is the use of an electric shock through the chest wall to correct Ventricular Fibrillation. A defibrillator is a device used for this purpose. 


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Dr. Avinash Kumar Singh
Cardiac Care
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