Cardiac arrest happens suddenly and without warning. One moment someone seems fine, the next they collapse. Unlike what you see in movies, cardiac arrest is a medical emergency that stops the heart completely. Understanding cardiac arrest causes can help you recognize risk factors and potentially save a life.
Every year, hundreds of thousands of people experience cardiac arrest. Many don’t survive because help doesn’t arrive fast enough. Knowing what causes cardiac arrest and how to respond makes a critical difference in outcomes.
What is Cardiac Arrest?
Cardiac arrest occurs when your heart suddenly stops beating. This is different from a heart attack, though people often confuse the two. During cardiac arrest, the heart’s electrical system malfunctions. It stops pumping blood to your brain, lungs, and other organs.
Without immediate treatment, cardiac arrest leads to death within minutes. The brain can only survive about 4-6 minutes without oxygen before permanent damage occurs. Every second counts when someone experiences cardiac arrest.
The condition can happen to anyone, anywhere. It strikes people at home, at work, during exercise, or even while sleeping.
How the Heart’s Electrical System Works
Your heart beats because of electrical signals. These signals travel through your heart in a coordinated pattern, telling different parts when to contract. A normal heart beats 60-100 times per minute in a steady rhythm.
The heart’s natural pacemaker, called the sinoatrial node, generates these electrical impulses. They spread through the upper chambers, then down to the lower chambers. This coordination ensures blood pumps efficiently throughout your body.
When something disrupts this electrical system, dangerous heart rhythms develop. The most common rhythm during cardiac arrest is ventricular fibrillation. During this, the heart’s lower chambers quiver uselessly instead of pumping blood.
Understanding how the heart’s electrical system works helps explain the various cardiac arrest causes and why they’re so dangerous.
What Causes Cardiac Arrest
The reasons for cardiac arrest typically involve problems with the heart’s structure or electrical system. Some causes develop over years, while others happen suddenly.
Coronary Artery Disease:
This is the leading cardiac arrest cause in adults. Coronary artery disease happens when plaque builds up in the arteries that supply blood to your heart muscle. According to the American Heart Association, this accounts for most sudden cardiac arrest causes in people over 35.
When these arteries narrow or become blocked, parts of the heart muscle don’t get enough oxygen. This can trigger dangerous heart rhythms. Sometimes the first symptom of coronary artery disease is cardiac arrest itself.
Heart Attack:
A heart attack can lead to cardiac arrest. During a heart attack, blood flow to part of the heart gets blocked. This damages heart muscle and can disrupt the electrical signals. The damaged tissue creates irregular electrical pathways that cause life-threatening rhythms.
Cardiomyopathy:
This refers to diseases that affect the heart muscle itself. The heart becomes enlarged, thick, or rigid. These structural changes interfere with the heart’s ability to pump blood and maintain normal electrical activity. Cardiomyopathy can be inherited or develop from infections, alcohol abuse, or certain medications.
Heart Valve Problems:
Faulty heart valves force the heart to work harder. Over time, this stress can lead to heart failure and electrical disturbances. Severe valve problems significantly increase the risk of cardiac arrest.
Congenital Heart Defects:
Some people are born with heart abnormalities. These structural problems can affect the heart’s electrical system. Young people who experience cardiac arrest often have undiagnosed congenital heart conditions.
Electrical Disorders:
Conditions like long QT syndrome, Brugada syndrome, or Wolff-Parkinson-White syndrome affect the heart’s electrical system directly. These inherited disorders can become sudden cardiac arrest causes even in people with structurally normal hearts. These conditions often run in families.
Ventricular Fibrillation and Ventricular Tachycardia:
These abnormal heart rhythms are immediate triggers for cardiac arrest causes. They can result from any of the conditions mentioned above or occur spontaneously in some cases.
Other Contributing Factors
Beyond primary heart conditions, several factors increase what causes cardiac arrest risk:
- Drug Abuse: Cocaine, methamphetamines, and other stimulants can trigger cardiac arrest. They cause the heart to beat irregularly or put extreme stress on the cardiovascular system.
- Severe Blood Loss: Massive bleeding reduces the volume of blood the heart has to pump, potentially leading to cardiac arrest.
- Lack of Oxygen: Drowning, choking, or respiratory failure deprives the heart of oxygen. Without oxygen, the heart’s electrical system fails.
- Electrolyte Imbalances: Potassium, magnesium, and calcium help regulate heart rhythm. Severe imbalances from kidney disease, dehydration, or eating disorders can trigger dangerous rhythms.
- Trauma: Severe chest injuries from accidents can damage the heart or disrupt its electrical signals. A blow to the chest at the wrong moment can cause cardiac arrest in young athletes.
High-Risk Groups
Certain people face higher risk of cardiac arrest causes. Age matters, with risk increasing after 45 for men and after 55 for women. Family history of heart disease or sudden cardiac death significantly raises your risk.
People with existing heart conditions, diabetes, high blood pressure, high cholesterol, or obesity face elevated risk. Smokers have double the risk of non-smokers. Those who’ve already had a cardiac arrest or heart attack are at much higher risk of another event.
Athletes with undiagnosed heart conditions, people taking certain medications that affect heart rhythm, and those with sleep apnea also belong to high-risk groups.
Warning Signs Before Cardiac Arrest
Cardiac arrest often strikes without warning, but some people experience symptoms in the hours, days, or weeks before. These warning signs include:
- Chest pain or discomfort
- Shortness of breath
- Heart palpitations or racing heartbeat
- Dizziness or lightheadedness
- Unexplained fatigue
Some people faint repeatedly before cardiac arrest. If you experience any of these symptoms, especially if you have risk factors, see a doctor immediately. The Cardiac Sciences department at Kokilaben Hospital Mumbai specializes in diagnosing and treating conditions that lead to cardiac arrest causes.
How to Reduce the Risk
You can’t prevent all reasons for cardiac arrest, but you can reduce your risk. Get regular health checkups to monitor blood pressure, cholesterol, and blood sugar. Manage existing heart conditions according to your doctor’s instructions.
Quit smoking and limit alcohol consumption. Maintain a healthy weight through balanced diet and regular exercise. At least 150 minutes of moderate exercise weekly is recommended.
If you have a family history of sudden cardiac death or known heart conditions, talk to your doctor about screening tests. Some high-risk people benefit from implantable cardioverter-defibrillators that can shock the heart back into normal rhythm.
What To Do During a Cardiac Arrest Emergency
If someone collapses and isn’t breathing normally, assume cardiac arrest and act immediately:
- Call emergency services right away
- Start CPR by pushing hard and fast in the center of the chest at least 100-120 times per minute
- If an AED is available, use it. These devices give voice instructions and will only deliver a shock if needed
- Continue CPR until emergency responders arrive or the person starts breathing
Quick action makes survival possible. The Critical Care team at Kokilaben Hospital Mumbai provides advanced life support for cardiac arrest patients.
When to See a Doctor
See a doctor if you have chest pain, shortness of breath, heart palpitations, unexplained fainting, or a family history of sudden cardiac death under age 50. Don’t ignore these warning signs. Early detection and treatment of heart conditions prevent many cardiac arrest causes.
If you’ve survived cardiac arrest, work closely with a cardiologist to identify what causes cardiac arrest and prevent future episodes.
FAQs
1. Can stress cause cardiac arrest?
Extreme stress can trigger cardiac arrest causes in people with underlying heart conditions. Stress hormones increase heart rate and blood pressure, which can provoke dangerous rhythms in vulnerable hearts.
2. Is cardiac arrest the same as a heart attack?
No. A heart attack blocks blood flow to the heart. Cardiac arrest causes the heart to stop beating entirely due to electrical malfunction. A heart attack can lead to cardiac arrest, but they’re different conditions.
3. Can young and healthy people have cardiac arrest?
Yes. Young people who experience sudden cardiac arrest causes often have undiagnosed genetic heart conditions or structural heart abnormalities. Athletes sometimes have cardiac arrest during intense activity due to undetected problems.
4. Can dehydration or exhaustion cause cardiac arrest?
Severe dehydration can cause electrolyte imbalances that become reasons for cardiac arrest. Extreme exhaustion, especially combined with dehydration and heat, stresses the cardiovascular system and increases risk.
5. Does caffeine increase the risk of cardiac arrest?
Moderate caffeine doesn’t increase cardiac arrest causes risk in most people. However, excessive caffeine can trigger dangerous heart rhythms in people with underlying conditions. Discuss caffeine intake with your doctor if you have heart disease.
