The Difference between Sudden Cardiac Arrest vs Heart Attack
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Sudden Cardiac Arrest vs Heart Attack Facts

Although the terms cardiac arrest and heart attack are used interchangeably by non-medical professionals, the reality is that these two conditions are entirely different.

Sudden Cardiac Arrest kills roughly 90% of its victims and survival is almost wholly dependent on how fast aid can be rendered. For each passing minute after an SCA event begins, the victim’s chances of survival diminish by 10%. There are an estimated 356,000 Sudden Cardiac Arrest cases annually in the United States alone.

Make no mistake, yes, a heart attack can kill you. Annually in the United States, there are an estimated one million heart attacks.  However, roughly 86% of heart attack victims survive the episode.

Knowing the difference between the two is key in identifying how and when to use a portable AED device. An AED will help especially with sudden cardiac arrest as it corrects electrical arrhythmia. Although the two conditions are different, sudden cardiac arrest may occur during a heart attack or during the recovery of a heart attack.

What is Sudden Cardiac Arrest?

Sudden Cardiac Arrest is an electrical malfunction of the heart that causes the heart to stop functioning and pump blood to other parts of the body. The electrical malfunction causes an arrhythmia or irregular heartbeat which can literally stop the heart leading to the heart no longer functioning. Shockingly, SCA is the number one cause of natural death in the United States, resulting in around 356,000 adult deaths in the United States each year and every year.

What Causes Sudden Cardiac Arrest?

The usual main cause of Sudden Cardiac Arrest is an abnormal heart rhythm called arrhythmia.

Electrical signals in the cardiovascular system control how the heart operates. If the electrical signals are disrupted, the heart may beat too fast, too slow or irregularly.

The Mayo Clinic describes the technical aspect of the cause of SCA as a rapid, erratic electrical impulses cause your ventricles to quiver uselessly instead of pumping blood (ventricle fibrillation).

A tendency to have arrhythmias runs in some families. This tendency is inherited, which means it’s passed from parents to children through genes. Members of these families may be at higher risk for SCA. Examples of inherited disorders that makes you more likely to have arrhythmias are:

  • Long QT syndrome (LQTS) –  LQTS is a disorder of the heart’s electrical activity. Problems with tiny pores on the surface of heart muscle cells cause the disorder. LQTS can cause sudden, uncontrollable, dangerous heart rhythms.
  • Cardiomyopathy (enlarged heart) – Cardiomyopathy is a condition that affects the ability of the heart muscle to pump effectively. There are different types of cardiomyopathies:
    • Dilated Cardiomyopathy – This is the most common type of cardiomyopathy. One or more chambers of the heart become enlarged, and the muscles that make up the walls of the heart become stretched and thinner than normal. This stretching further weakens the muscles, and the heart is not able to pump blood as strongly.
    • Hypertrophic Cardiomyopathy – Muscles in the heart become abnormally thickened, and the heart has to work harder to push the same amount of blood through the body. In obstructive hypertrophic cardiomyopathy, the thickened muscles push into a chamber of the heart, blocking blood flow and sometimes causing the mitral valve of the heart to leak.
    • Restrictive Cardiomyopathy – In this rare type, the heart muscles become stiff, and the ventricles of the heart are not able to relax and completely fill with blood between heartbeats.
    • Arrhythmogenic Right Ventricular Cardiomyopathy – Heart muscle cells are replaced by scar tissue or fat, leading to disturbances in the electrical signaling of the heart. These disturbances can cause sudden cardiac death.
  • Coronary Heart Disease (CHD) – CHD is a disease in which a waxy substance called plaque builds up in the coronary arteries. These arteries supply oxygen-rich blood to your heart muscle. When plaque builds up in the arteries, the condition is called atherosclerosis. Arteries are blood vessels that carry oxygen-rich blood to your heart and other parts of your body. Eventually, an area of plaque can rupture and may cause a blood clot to form on the plaque’s surface. A blood clot can partly or fully block the flow of oxygen-rich blood to the portion of heart muscle fed by the artery. This causes a heart attack, during which some heart muscle cells die and are replaced with scar tissue. The scar tissue damages the heart’s electrical system. As a result, electrical signals may spread abnormally throughout the heart. These changes to the heart increase the risk of dangerous arrhythmias and SCA.

Who is at most risk for Sudden Cardiac Arrest

While Sudden Cardiac Arrest can occur to anyone at any given time, studies show that people with pre-existing conditions such as coronary artery disease, enlarged hearts, myocarditis, valvular heart disease, congenital heart conditions or electrical problems in the heart are at higher risk.

Obesity, smoking, blood pressure concerns and a family history of heart-related issues can raise the risk of SCA.

Studies show that those over the age of 45 are at an increased risk of SCA overall, however roughly 7,000 minors each year suffer SCA each year.

What are Symptoms of Sudden Cardiac Arrest?

Sudden Cardiac Arrest symptoms usually onset rapidly with little to no warning. Usually before a victim collapses, there are a few moments that indicate shortness or breath or chest pains. 

Unfortunately, the time period between the beginning indicators and the victim becoming unconscious is very narrow, if at all. 

The lack of a heartbeat or breathing are two indicators for responders to look for as it could be the green light to deploy an Automated External Defibrillator. 

Other symptoms may include:

  • Chest Pain
  • Dizziness
  • Rapid onset fatigue
  • Difficulty breathing

Can Athletes die of Sudden Cardiac Arrest?

Sadly, yes. And it is not as rare of an occurrence as one may think. Sudden cardiac arrest is the number one most common medical cause of death in athletes, with a global incidence of around 1 in 40,000 to 1 in 80,000 athletes each year.

Approximately one-third of athletes who have suffered and survived a SCA reported having chest pain, shortness of breath, performance decline, palpitations, pre-syncope, or syncope prior to the event.

Congenital/Genetic or acquired heart abnormalities may play a role in athletes with sudden cardiac arrest, such as; myocarditis, Kawasaki’s, valvular heart disease and more.

What is a Heart Attack?

A heart attack is an entirely different cardiac event. A heart attack occurs when blood flow is stopped by a blockage in one of the arteries. The symptoms of a heart attack also start much earlier, sometimes as earlier is a few weeks, days, or hours before and the heart may not fully stop during a heart attack. Heart attacks are also risk related to people with known heart disease, obesity, or other medical conditi

What Causes Heart Attacks?

Heart attacks are primarily caused by blockages in the coronary arteries. Buildups of fatty deposits, commonly referred to as plaque, prevent the flow of oxygen-rich blood to the rest of the body.

Contrary to SCA, heart attacks are linked more to the lack of blood flow rather than an electrical issue.

Who is at most risk for a Heart Attack?

There are many factors that are taken into consideration when evaluating someone’s risk of suffering a heart attack. High blood pressure or cholesterol, obesity, diabetes, tobacco and alcohol use, age and diabetes are just some of the main risk factors for heart attacks.

Other attributing factors for heart attacks are poor diet and exercise, emotional stress and genes. 

What are symptoms of a Heart Attack?

Generally, symptoms of a heart attack include several pain areas across the body. Most notably in the chest region but also may include the jaw area or left arm.

Women are more likely than men to have atypical symptoms which may resemble other conditions or last longer than men. 

The types of pain range in several different ways. The most common is a “clenched fist” type of pain in the chest region.

Contrary to Sudden Cardiac Arrest which has little to no immediate symptoms, heart attacks typically give off explicit warning signs. 

Why use an AED for Sudden Cardiac Arrest?

It only takes 10 minutes to die from SCA, and people assume that if EMS is needed they will make it in time to save a victim from SCA. However, the American Heart Association (AHA) has confirmed that in order for an SCA victim to survive, defibrillation must take place within 3-4 minutes of cardiac arrest. AHA has also confirmed that an EMS call–to-shock time interval of <5 minutes cannot be reliably achieved with conventional EMS services. What this means is, if there is not an AED readily available near the scene, the victim will most likely die from SCA.

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