While often confused, heart attacks and cardiac arrest are distinct medical emergencies. Understanding their differences in causes, symptoms, and immediate responses is crucial.
What is a Heart Attack
A heart attack, known medically as a myocardial infarction, occurs when blood flow to a section of the heart muscle becomes blocked. This blockage is typically due to a blood clot forming in one of the coronary arteries, which supply oxygen-rich blood to the heart. When the heart muscle is deprived of blood and oxygen, the affected tissue begins to die, leading to damage.
Symptoms of a heart attack can vary, but common signs include chest pain that may feel like pressure, squeezing, or fullness. This discomfort can spread to other areas such as the arm, neck, jaw, back, or stomach. Other symptoms may include shortness of breath, nausea, lightheadedness, or a cold sweat.
What is Cardiac Arrest
Cardiac arrest is an electrical problem where the heart’s electrical activity becomes chaotic, causing it to suddenly stop beating effectively or altogether. This abrupt cessation of the heart’s pumping action leads to an immediate loss of blood flow to the brain and other organs. When the heart stops, the individual loses consciousness, collapses, and stops breathing.
This condition is often caused by an underlying heart issue, such as a severe arrhythmia like ventricular fibrillation, where the heart’s lower chambers quiver uselessly instead of pumping blood. Without immediate intervention, the lack of oxygen-rich blood reaching the brain can result in brain damage or death within minutes. Cardiac arrest is a sudden event that can occur without any prior warning signs.
Comparing the Conditions
Heart attacks and cardiac arrest are both life-threatening cardiac emergencies, but they stem from different underlying issues. A heart attack is a circulation problem, involving a blockage that restricts blood flow to the heart muscle. Cardiac arrest is an electrical problem, where the heart’s electrical system malfunctions, causing it to stop beating.
A heart attack can sometimes lead to cardiac arrest, particularly if the damage to the heart muscle is extensive or affects the heart’s electrical system. However, many heart attacks do not immediately result in cardiac arrest. The key distinction lies in the heart’s function: in a heart attack, the heart is still beating with impaired blood flow, while in cardiac arrest, the heart’s pumping action ceases entirely.
Emergency Response
For a suspected heart attack, immediate action involves calling emergency services (such as 911 in the U.S.) without delay. While waiting for medical help, the person should be kept calm, and any tight clothing should be loosened. If medically advised and not allergic, chewing a 300mg aspirin can help thin the blood and improve blood flow.
For cardiac arrest, the response must be even more immediate due to the complete cessation of blood flow. After calling emergency services, starting chest compressions (CPR) without delay is crucial. If an automated external defibrillator (AED) is available, it should be used following its voice prompts, as defibrillation can restore a normal heart rhythm. Continuous chest compressions are vital until professional medical help arrives.