Sudden cardiac arrest can happen without warning, even when someone is active, like playing basketball or walking with friends.
The person may suddenly collapse, pass out, and stop breathing. This happens because their heart stops beating properly and cannot pump blood. When the heart stops, blood cannot reach the brain, and the person quickly loses consciousness.
This dangerous situation is often caused by a serious heart rhythm problem, known as a lethal arrhythmia. It makes the heart beat in an abnormal way so it can’t pump blood efficiently. That’s why sudden cardiac arrest is so dangerous.
Some people confuse a heart attack with sudden cardiac arrest, but they are not the same. A heart attack happens when a blood vessel in the heart gets blocked.
This stops blood from reaching parts of the heart muscle, and people may feel chest pain or have trouble breathing. However, a heart attack can sometimes lead to sudden cardiac arrest if it causes the heart to go into a deadly rhythm due to lack of oxygen.
Two dangerous rhythms that can cause sudden cardiac arrest are ventricular fibrillation and ventricular tachycardia. These conditions make the heart beat too fast and lose the ability to pump blood properly. That cuts off blood to the brain and other vital organs.
Dr. Brian Shapiro from Mayo Clinic says that if someone collapses from cardiac arrest, you should call 911 right away. If possible, ask for an automated external defibrillator, or AED. These machines are often found in public places like gyms, malls, or airports. If the area is safe, start chest compressions or CPR immediately.
The AED is easy to use—it gives clear instructions and tells you what to do even if you’ve never used one before. It checks the person’s heart rhythm and gives a shock if needed to help restore a normal heartbeat.
Although sudden cardiac arrest is rare, the risk depends on age and health. In people under 35, it is often linked to a hidden heart condition called hypertrophic cardiomyopathy.
This means part of the heart muscle is thicker than normal, which can lead to irregular heartbeats. This condition is most common in young athletes and affects about one in every 500 people.
In people over 35, sudden cardiac arrest is more likely to be caused by coronary artery disease. This condition happens when cholesterol builds up in the arteries and blocks blood flow to the heart.
Things like high blood pressure, diabetes, smoking, and family history increase the risk. If a cholesterol plaque in the artery breaks, it can cause a heart attack that leads to dangerous heart rhythms.
Both inactive people and high-level athletes can be at risk. People who don’t exercise much may have weak hearts. On the other hand, athletes like marathon runners put a lot of stress on their hearts. That’s why it’s important for doctors to check anyone with symptoms or a family history of heart problems.
Doctors can look for signs of risk during a physical exam by listening for heart murmurs or using tests like an electrocardiogram (EKG), chest X-ray, or even a stress test with a special breathing mask. These tests can find hidden heart or lung issues.
With this information, doctors can help design safe exercise plans based on your health. Staying active is important for both your body and your mind, but it’s also important to do it safely—especially if you have any heart risk factors.
If you care about heart health, please read studies that yogurt may help lower the death risks in heart disease, and coconut sugar could help reduce artery stiffness.
For more information about health, please see recent studies that Vitamin D deficiency can increase heart disease risk, and results showing vitamin B6 linked to lower death risk in heart disease.
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