Sudden Cardiac Arrest – Symptoms and Causes
Understanding Sudden Cardiac Arrest
Sudden cardiac arrest (SCA) happens when the heart suddenly stops beating effectively due to irregular heart rhythms. During SCA, a person stops breathing and loses consciousness. Without quick treatment, SCA can be fatal.
Immediate emergency care is crucial for survival. This includes:
- Cardiopulmonary resuscitation (CPR)
- Use of an automated external defibrillator (AED) to deliver electric shocks to the heart
It’s important to understand that SCA differs from a heart attack. A heart attack occurs when blood flow to part of the heart muscle is blocked.
On the other hand, SCA isn’t caused by blockage but involves an electrical problem with the heart’s rhythm. However, a heart attack can sometimes trigger changes in the heart’s electrical system that lead to SCA.
With fast, appropriate medical intervention, people can survive sudden cardiac arrest.
Signs of Sudden Cardiac Arrest
Sudden cardiac arrest happens without warning. The person collapses, has no pulse, stops breathing, and loses consciousness immediately.
Some people may have warning signs before cardiac arrest occurs:
- Chest Pain or Discomfort
- Trouble Breathing
- Feeling Weak
- Heart Palpitations (fast, fluttering, or pounding heartbeat)
Many times, however, there are no warning signs at all.
When to Get Medical Help
When someone’s heart stops beating, their brain doesn’t get oxygen. This can cause death or permanent brain damage very quickly.
Call 911 right away if you notice:
- Chest pain
- Pounding heartbeat
- Irregular or fast heartbeats
- Unexplained wheezing
- Difficulty breathing
- Fainting or almost fainting
- Feeling dizzy or lightheaded
If you find someone unconscious and not breathing, call 911 immediately. Then start CPR. Push hard and fast on their chest. Use an AED if one is nearby.
How to Perform CPR
If someone isn’t breathing, follow these steps:
- Place your hands in the center of their chest.
- Push hard and fast—about 100-120 compressions per minute.
- Allow the chest to rise completely between pushes.
If you’ve learned CPR, check the airway and give two rescue breaths after every 30 chest compressions.
If you haven’t been trained, just keep pushing on the chest until help arrives or an AED becomes available.
About AEDs:
- Found in many public places like malls and airports
- Available for home purchase through Healthnile.com
- Include voice instructions for proper use
- Only deliver a shock when the person needs it
Keep performing CPR until emergency workers arrive or the person begins breathing again.
What Leads to Sudden Cardiac Arrest
The heart beats using electrical signals. These signals control how fast and steady your heart pumps. When these signals work properly, your heart beats in a normal pattern.
But sometimes, faulty signals can make your heart beat too fast, too slow, or in an uneven way.
These unusual heart rhythms are called arrhythmias. While some arrhythmias are brief and harmless, others can lead to sudden cardiac arrest when the heart stops pumping blood.
Heart Problems That May Cause Sudden Cardiac Arrest
The most common cause of sudden cardiac arrest is ventricular fibrillation, a dangerous irregular heart rhythm. In this condition, the lower chambers of the heart quiver instead of pumping blood effectively.
Many heart conditions increase the risk of this happening, though sudden cardiac arrest can also occur in people with no known heart problems.
Heart conditions that raise the risk include:
Clogged Arteries: When cholesterol and other substances build up in the heart’s blood vessels, blood flow decreases, potentially triggering cardiac arrest.
Heart Attack: A heart attack can cause ventricular fibrillation and sudden cardiac arrest. The scarring that follows a heart attack can also create irregular heart rhythms.
Enlarged Heart: Also called cardiomyopathy, this happens when heart walls stretch and the heart muscle grows bigger or thicker than normal.
Valve Problems: When heart valves leak or narrow, the heart muscle may stretch or thicken. This extra stress increases the risk of developing dangerous heart rhythms.
Birth Defects: Heart problems present since birth often cause sudden cardiac arrest in young people. Adults who’ve had surgery for these defects still face higher risks.
Electrical Signal Disorders: Conditions like long QT syndrome (LQTS) and Brugada syndrome cause disorganized heart rhythms. These can quickly become life-threatening, especially in young people with LQTS.
Risk Factors
| Risk Factors | How It Affects the Heart |
|---|---|
| High blood pressure | Strains heart muscle over time |
| High cholesterol | Contributes to artery blockages |
| Smoking | Damages blood vessels |
| Family history | Increases genetic risk |
| Age | Risk grows as people get older |
Heart disease risk factors play a major role, including:
- Elevated cholesterol levels
- Obesity
- Diabetes
- Lack of physical activity
Additional risk factors include:
- Previous cardiac arrest episodes
- Prior heart attacks
- Personal or family history of heart conditions (rhythm disorders, heart failure, congenital heart problems)
- Advanced age
- Male gender
- Illegal drug use (especially cocaine or amphetamines)
- Low potassium or magnesium in the body
- Obstructive sleep apnea
- Chronic kidney disease
Complications
Cardiac arrest reduces blood flow to the brain. If normal heart rhythm isn’t quickly restored, serious problems can follow. Brain damage may occur within minutes as brain cells die without oxygen.
Without fast treatment, cardiac arrest often leads to death.
Ways to Prevent Cardiac Arrest
Heart health is key to preventing sudden cardiac arrest. You can take several steps to protect your heart:
Healthy Lifestyle Habits:
- Maintain a nutritious diet
- Exercise regularly
- Avoid tobacco products
- Schedule regular medical checkups
- Get heart disease screenings
Managing Health Conditions:
- Control blood pressure levels
- Keep cholesterol within healthy ranges
Genetic testing can identify long QT syndrome, a common cause of sudden cardiac death. Before getting tested, check with your insurance company about coverage.
If you test positive for the long QT gene, your doctor may suggest that your family members get tested too.
People with known cardiac arrest risks might benefit from an implantable cardioverter-defibrillator (ICD). This device is surgically placed under the collarbone and helps regulate heart rhythm.
Some people consider buying an automated external defibrillator (AED) for home use. These devices can reset heart rhythm during sudden cardiac arrest.
Talk with your healthcare team about whether this option makes sense for you. Be aware that AEDs can be costly and may not be covered by insurance.
