Difference Between a Heart Attack and a Cardiac Arrest

By Dr. Salil Shirodkar in Heart Institute

Jul 01 , 2023 | 8 min read

What is a heart attack?

A heart attack, also known as myocardial infarction, occurs when the blood flow to a section of the heart muscle is blocked, usually by a blood clot. This blockage can cause damage to the heart muscle and can be life-threatening. Common symptoms of a heart attack include chest pain or discomfort, shortness of breath, nausea, lightheadedness, and cold sweats.

It's important to seek medical attention immediately if an individual experiences any of these symptoms, as prompt treatment can reduce the damage to the heart muscle and improve the chances of survival. Risk factors for a heart attack include high blood pressure, high cholesterol, smoking, obesity, and a family history of heart disease.

What is cardiac arrest?

Cardiac arrest is different from a heart attack. While a heart attack is caused by a blockage in the blood vessels that supply the heart muscle with oxygen, cardiac arrest occurs when the heart suddenly stops beating. This can be caused by a variety of factors, such as an abnormal heart rhythm, a heart attack, or a severe electrolyte imbalance.

Unlike a heart attack, cardiac arrest is a medical emergency that requires immediate intervention, such as CPR (cardiopulmonary resuscitation) and defibrillation, to restore the heart's normal rhythm. Without prompt treatment, cardiac arrest can be fatal within minutes.

How do symptoms of a heart attack and cardiac arrest compare?

Symptoms of a heart attack

A heart attack can cause a range of symptoms that vary from person to person. The most common symptom of a heart attack is chest pain or discomfort, which may be described as a tightness, pressure, or squeezing sensation in the chest. This pain may also radiate to the arms, neck, jaw, or back.

Other symptoms of a heart attack may include shortness of breath, nausea or vomiting, lightheadedness, and cold sweats. Women, elderly individuals, and people with diabetes may experience atypical symptoms, such as fatigue, weakness, or indigestion.

Symptoms of cardiac arrest

Cardiac arrest often occurs suddenly and without warning, and can cause a range of symptoms. The most common symptom of cardiac arrest is a sudden loss of consciousness, followed by an absence of pulse and cessation of breathing. Other signs may include gasping or seizure-like activity, as the body tries to restore normal breathing and blood flow.

Cardiac arrest can also cause other symptoms, such as chest pain or discomfort, nausea or vomiting, and lightheadedness. However, these symptoms are less common and may not be present in all cases. It's important to recognize the signs of cardiac arrest and seek emergency medical attention immediately, as it can be a life-threatening condition.

Symptom comparison table of heart attack vs cardiac arrest

The table below shows common symptoms of heart attack vs cardiac arrest.

Symptoms of heart attack

Symptoms of cardiac arrest

The severity of symptoms may change over time, though not always. Chest pain is the most frequently reported symptom.

As time passes, symptoms may become more prominent (though not always).

Chest ache, tightness, or uneasiness experienced in the middle or left side of the torso.

Repeated dizziness or fainting

Agonising aches or uneasiness in both upper and lower extremities, the back, shoulders, neck, jaw, or even above the naval area.

Weakness or fatigue

Difficulty with breathing when attempting even simple tasks, or simply when at rest (mostly common in older adults)

Shortness of breath

Excessive sweating for no reason

Nausea or vomiting

Unusual tiredness, lasting for days (mostly common in women)

No breath or difficulty in taking a breath

Nausea or vomiting

Heart palpitations or chest pain

Sudden dizziness or lightheadedness

No pulse

Irregular or rapid heart rate

Loss of consciousness

Causes & risk factors of a heart attack vs cardiac arrest

While heart attack vs cardiac arrest has diverse causes and risks, those suffering from a heart attack usually know that they are at risk. Those experiencing cardiac arrest, however, are often caught off-guard and are not aware of any cardiac issues that they might have.

Causes of heart attack

Most heart attacks stem from coronary heart disease, a condition that obstructs the flow of oxygen to the heart. Often, those at risk of experiencing a heart attack are those that are receiving treatment for coronary heart disease. Other causes and risk factors include:

  • High blood pressure: High blood pressure can damage the arteries and make them more likely to develop plaque buildup.
  • High cholesterol: High levels of cholesterol can contribute to plaque buildup in the arteries.
  • Smoking: Smoking damages the blood vessels and increases the risk of blood clots.
  • Diabetes: People with diabetes are at higher risk of a heart attack because high blood sugar can damage the blood vessels.
  • Family history of heart disease: People with a family history of heart disease are at higher risk of a heart attack.
  • Obesity or overweight: Being overweight or obese increases the risk of a heart attack.
  • Sedentary lifestyle: Lack of physical activity can contribute to the development of risk factors for heart attack.
  • Stress: Chronic stress can increase the risk of a heart attack.

Causes of cardiac arrests

Those suffering from coronary heart disease and other cardiac-related issues are more prone to the possibility of cardiac arrest. Furthermore, other hidden and potentially dangerous conditions, unknown to the patient, can lead to an increased risk of such a life-threatening medical emergency. These include

  • Arrhythmias: These are abnormal heart rhythms that can cause the heart to stop beating properly.
  • Heart muscle disease (cardiomyopathy): This can weaken the heart muscle and cause it to stop beating.
  • Heart failure: This occurs when the heart cannot pump blood effectively, which can lead to cardiac arrest.
  • Electrolyte imbalances: An imbalance of electrolytes such as potassium or magnesium can affect the heart's electrical signals and cause cardiac arrest.
  • Drug overdose: Certain drugs, such as opioids, can slow down or stop the heart.
  • Trauma or injury to the chest: A severe blow to the chest can cause cardiac arrest.
  • Electric shock: An electric shock can disrupt the heart's rhythm and cause cardiac arrest.
  • Suffocation or choking: A lack of oxygen to the body can cause the heart to stop.

Heart attack vs cardiac arrest: What is the diagnosis difference?

A doctor can determine the difference between a heart attack vs cardiac arrest by conducting certain tests. This highlights the importance of seeking immediate medical attention if it is suspected that someone is having a heart attack or a cardiac arrest.

Diagnosing a heart attack

  • Medical history: A doctor will ask about symptoms, risk factors, and medical history.
  • Physical exam: The doctor will perform a physical exam to check for signs of a heart attack.
  • Electrocardiogram (ECG): This test records the electrical activity of the heart to look for signs of a heart attack.
  • Blood tests: Blood tests can detect enzymes and proteins released by attacked heart muscles.
  • Cardiac catheterization: A catheter is inserted into the heart to check for blockages in the arteries.
  • Echocardiogram: This test uses sound waves to create images of the heart and can detect damage or abnormalities.

Diagnosing a cardiac arrest

  • Emergency assessment: A medical professional will assess the person's breathing and pulse and begin emergency treatment if necessary.
  • Electrocardiogram (ECG): This test is used to diagnose cardiac arrest and determine the cause.
  • Blood tests: Blood tests can check for imbalances or abnormalities that may have caused cardiac arrest.
  • Imaging tests: Tests such as a chest X-ray or CT scan can identify any underlying conditions that may have caused cardiac arrest.
  • Cardiac catheterization: This test may be performed after resuscitation to check for blockages or other issues.
  • Coronary angiography: This test uses contrast dye and X-rays to visualize blood flow through the coronary arteries.

Comparing treatment options for a heart attack and cardiac arrest

Treatment options for a heart attack vs cardiac arrest are highly based upon factors such as a patient's existing medical conditions and any prescribed medications they may be taking, the severity of the heart attack or cardiac arrest, and the patient's general health and ability to endure surgeries or other medical treatments.

Treating a heart attack

  • Medications: Aspirin, clot-busting drugs, and other medications may be given to help dissolve clots or prevent further clotting.
  • Angioplasty and stenting: A catheter is inserted into the blocked artery and a balloon is inflated to widen the artery. A stent may also be inserted to keep the artery open.
  • Coronary artery bypass surgery: In some cases, surgery may be needed to bypass the blocked artery.
  • Lifestyle changes: Adopting a healthy diet, regular exercise, and quitting smoking can help prevent future heart attacks.
  • Cardiac rehabilitation: This involves supervised exercise and education to help patients recover from a heart attack and prevent future events.

Treating cardiac arrest

  • CPR: Cardiopulmonary resuscitation (CPR) is typically performed to help maintain blood flow and oxygen to the body.
  • Defibrillation: An electric shock is delivered to the heart to help restore a normal rhythm.
  • Medications: Drugs may be given to help restore heart function and maintain blood pressure.
  • Coronary angioplasty or bypass surgery: These procedures may be performed after resuscitation to address any underlying blockages in the arteries.
  • Therapeutic hypothermia: Cooling the body to a lower temperature can help prevent brain damage and improve outcomes.

What should someone with a heart attack do vs. what should someone with cardiac arrest do?

If someone is experiencing symptoms of a heart attack, it's important to seek medical attention immediately by calling emergency services or going to the nearest hospital. In the meantime, the following steps can be taken:

  • Sit down and rest, avoiding any strenuous activity.
  • Take aspirin, if it has been recommended by a doctor or if it is available and there are no contraindications.
  • Try to stay calm and reduce stress levels.

If someone is experiencing cardiac arrest, it's crucial to act quickly to improve their chances of survival. The following steps should be taken:

  • Call emergency services immediately and start CPR.
  • If an automated external defibrillator (AED) is available, use it as soon as possible.
  • Stay with the person until help arrives and continue performing CPR as instructed by emergency services.

It is important to note that prompt medical attention is critical in both cases, but the actions taken for a heart attack vs cardiac arrest differ significantly.